1
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Bonnet N, Baaboura J, Castioni F, Woo SY, Ho CH, Watanabe K, Taniguchi T, Tizei LHG, Coenen T. Cathodoluminescence emission and electron energy loss absorption from a 2D transition metal dichalcogenide in van der Waals heterostructures. NANOTECHNOLOGY 2024; 35:405702. [PMID: 38604153 DOI: 10.1088/1361-6528/ad3d62] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 04/11/2024] [Indexed: 04/13/2024]
Abstract
Nanoscale variations of optical properties in transition metal dichalcogenide (TMD) monolayers can be explored with cathodoluminescence (CL) and electron energy loss spectroscopy (EELS) using electron microscopes. To increase the CL emission intensity from TMD monolayers, the MoSe2flakes are encapsulated in hexagonal boron nitride (hBN), creating van der Waals (VdW) heterostructures. Until now, the studies have been exclusively focused on scanning transmission electron microscopy (STEM-CL) or scanning electron microscopy (SEM-CL), separately. Here, we present results, using both techniques on the same sample, thereby exploring a large acceleration voltage range. We correlate the CL measurements with STEM-EELS measurements acquired with different energy dispersions, to access both the low-loss region at ultra-high spectral resolution, and the core-loss region. This provides information about the weight of the various absorption phenomena including the direct TMD absorption, the hBN interband transitions, the hBN bulk plasmon, and the core losses of the atoms present in the heterostructure. The S(T)EM-CL measurements from the TMD monolayer only show emission from the A exciton. Combining the STEM-EELS and S(T)EM-CL measurements, we can reconstruct different decay pathways leading to the A exciton CL emission. The comparison with SEM-CL shows that this is also a good technique for TMD heterostructure characterization, where the reduced demands on sample preparation are appealing. To demonstrate the capabilities of SEM-CL imaging, we also measured on a SiO2/Si substrate, quintessential in the sample preparation of two-dimensional materials, which is electron-opaque and can only be measured in SEM-CL. The CL-emitting defects of SiO2make this substrate challenging to use, but we demonstrate that this background can be suppressed by using lower electron energy.
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Affiliation(s)
- Noémie Bonnet
- Delmic B.V., Kanaalweg 4, 2628 EB Delft, The Netherlands
| | - Jassem Baaboura
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, F-91405, Orsay, France
| | - Florian Castioni
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, F-91405, Orsay, France
| | - Steffi Y Woo
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, F-91405, Orsay, France
| | - Ching-Hwa Ho
- Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| | - Kenji Watanabe
- Research Center for Electronic and Optical Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Luiz H G Tizei
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, F-91405, Orsay, France
| | - Toon Coenen
- Delmic B.V., Kanaalweg 4, 2628 EB Delft, The Netherlands
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2
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Chen S, Zhang Y, King WP, Bashir R, van der Zande AM. Edge-Passivated Monolayer WSe 2 Nanoribbon Transistors. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2313694. [PMID: 39023387 DOI: 10.1002/adma.202313694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 07/06/2024] [Indexed: 07/20/2024]
Abstract
The ongoing reduction in transistor sizes drives advancements in information technology. However, as transistors shrink to the nanometer scale, surface and edge states begin to constrain their performance. 2D semiconductors like transition metal dichalcogenides (TMDs) have dangling-bond-free surfaces, hence achieving minimal surface states. Nonetheless, edge state disorder still limits the performance of width-scaled 2D transistors. This work demonstrates a facile edge passivation method to enhance the electrical properties of monolayer WSe2 nanoribbons, by combining scanning transmission electron microscopy, optical spectroscopy, and field-effect transistor (FET) transport measurements. Monolayer WSe2 nanoribbons are passivated with amorphous WOxSey at the edges, which is achieved using nanolithography and a controlled remote O2 plasma process. The same nanoribbons, with and without edge passivation are sequentially fabricated and measured. The passivated-edge nanoribbon FETs exhibit 10 ± 6 times higher field-effect mobility than the open-edge nanoribbon FETs, which are characterized with dangling bonds at the edges. WOxSey edge passivation minimizes edge disorder and enhances the material quality of WSe2 nanoribbons. Owing to its simplicity and effectiveness, oxidation-based edge passivation could become a turnkey manufacturing solution for TMD nanoribbons in beyond-silicon electronics and optoelectronics.
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Affiliation(s)
- Sihan Chen
- Holonyak Micro and Nanotechnology Laboratory, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Yue Zhang
- Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - William P King
- Holonyak Micro and Nanotechnology Laboratory, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Materials Research Laboratory, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Rashid Bashir
- Holonyak Micro and Nanotechnology Laboratory, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Arend M van der Zande
- Holonyak Micro and Nanotechnology Laboratory, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Department of Mechanical Science and Engineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
- Materials Research Laboratory, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
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3
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Maurtua C, Zide J, Chakraborty C. Molecular beam epitaxy and other large-scale methods for producing monolayer transition metal dichalcogenides. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:383003. [PMID: 38901422 DOI: 10.1088/1361-648x/ad5a5d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Accepted: 06/20/2024] [Indexed: 06/22/2024]
Abstract
Transition metal dichalcogenide (TMD/TMDC) monolayers have gained considerable attention in recent years for their unique properties. Some of these properties include direct bandgap emission and strong mechanical and electronic properties. For these reasons, monolayer TMDs have been considered a promising material for next-generation quantum technologies and optoelectronic devices. However, for the field to make more gainful advancements and be implemented in devices, high-quality TMD monolayers need to be produced at a larger scale with high quality. In this article, some of the current means to produce larger-scale semiconducting monolayer TMDs will be reviewed. An emphasis will be given to the technique of molecular beam epitaxy (MBE) for two main reasons: (1) there is a growing body of research using this technique to grow TMD monolayers and (2) there is yet to be a body of work that has summarized the current research for MBE monolayer growth of TMDs.
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Affiliation(s)
- Collin Maurtua
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, United States of America
| | - Joshua Zide
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, United States of America
| | - Chitraleema Chakraborty
- Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, United States of America
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4
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Rodríguez Á, Çakıroğlu O, Li H, Carrascoso F, Mompean F, Garcia-Hernandez M, Munuera C, Castellanos-Gomez A. Improved Strain Transfer Efficiency in Large-Area Two-Dimensional MoS 2 Obtained by Gold-Assisted Exfoliation. J Phys Chem Lett 2024; 15:6355-6362. [PMID: 38857301 PMCID: PMC11194808 DOI: 10.1021/acs.jpclett.4c00855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/31/2024] [Accepted: 06/05/2024] [Indexed: 06/12/2024]
Abstract
Strain engineering represents a pivotal approach to tailoring the optoelectronic properties of two-dimensional (2D) materials. However, typical bending experiments often encounter challenges, such as layer slippage and inefficient transfer of strain from the substrate to the 2D material, hindering the realization of their full potential. In our study, using molybdenum disulfide (MoS2) as a model 2D material, we have demonstrated that layers obtained through gold-assisted exfoliation on flexible polycarbonate substrates can achieve high-efficient strain transfer while also mitigating slippage effects, owing to the strong interfacial interaction established between MoS2 and gold. We employ differential reflectance and Raman spectroscopy for monitoring strain changes. We successfully applied uniaxial strains of up to 3% to trilayer MoS2, resulting in a notable energy shift of 168 meV. These values are comparable only to those obtained in encapsulated samples with organic polymers.
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Affiliation(s)
- Álvaro Rodríguez
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid (ICMM)−Consejo
Superior de Investigaciones Científicas (CSIC), C. Sor Juana Inés de la Cruz,
3, 28049 Madrid, Spain
| | - Onur Çakıroğlu
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid (ICMM)−Consejo
Superior de Investigaciones Científicas (CSIC), C. Sor Juana Inés de la Cruz,
3, 28049 Madrid, Spain
| | - Hao Li
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid (ICMM)−Consejo
Superior de Investigaciones Científicas (CSIC), C. Sor Juana Inés de la Cruz,
3, 28049 Madrid, Spain
| | - Felix Carrascoso
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid (ICMM)−Consejo
Superior de Investigaciones Científicas (CSIC), C. Sor Juana Inés de la Cruz,
3, 28049 Madrid, Spain
| | - Federico Mompean
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid (ICMM)−Consejo
Superior de Investigaciones Científicas (CSIC), C. Sor Juana Inés de la Cruz,
3, 28049 Madrid, Spain
| | - Mar Garcia-Hernandez
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid (ICMM)−Consejo
Superior de Investigaciones Científicas (CSIC), C. Sor Juana Inés de la Cruz,
3, 28049 Madrid, Spain
| | - Carmen Munuera
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid (ICMM)−Consejo
Superior de Investigaciones Científicas (CSIC), C. Sor Juana Inés de la Cruz,
3, 28049 Madrid, Spain
| | - Andres Castellanos-Gomez
- Materials Science Factory, Instituto de Ciencia de Materiales de Madrid (ICMM)−Consejo
Superior de Investigaciones Científicas (CSIC), C. Sor Juana Inés de la Cruz,
3, 28049 Madrid, Spain
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5
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Zhu S, Duan R, Xu X, Sun F, Chen W, Wang F, Li S, Ye M, Zhou X, Cheng J, Wu Y, Liang H, Kono J, Li X, Liu Z, Wang QJ. Strong nonlinear optical processes with extraordinary polarization anisotropy in inversion-symmetry broken two-dimensional PdPSe. LIGHT, SCIENCE & APPLICATIONS 2024; 13:119. [PMID: 38802363 PMCID: PMC11130276 DOI: 10.1038/s41377-024-01474-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 05/03/2024] [Accepted: 05/09/2024] [Indexed: 05/29/2024]
Abstract
Nonlinear optical activities, especially second harmonic generation (SHG), are key phenomena in inversion-symmetry-broken two-dimensional (2D) transition metal dichalcogenides (TMDCs). On the other hand, anisotropic nonlinear optical processes are important for unique applications in nano-nonlinear photonic devices with polarization functions, having become one of focused research topics in the field of nonlinear photonics. However, the strong nonlinearity and strong optical anisotropy do not exist simultaneously in common 2D materials. Here, we demonstrate strong second-order and third-order susceptibilities of 64 pm/V and 6.2×10-19 m2/V2, respectively, in the even-layer PdPSe, which has not been discovered in other common TMDCs (e.g., MoS2). Strikingly, it also simultaneously exhibited strong SHG anisotropy with an anisotropic ratio of ~45, which is the largest reported among all 2D materials to date, to the best of our knowledge. In addition, the SHG anisotropy ratio can be harnessed from 0.12 to 45 (375 times) by varying the excitation wavelength due to the dispersion ofχ ( 2 ) values. As an illustrative example, we further demonstrate polarized SHG imaging for potential applications in crystal orientation identification and polarization-dependent spatial encoding. These findings in 2D PdPSe are promising for nonlinear nanophotonic and optoelectronic applications.
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Affiliation(s)
- Song Zhu
- School of Electrical and Electronic Engineering, Nanyang Technological University, 639798, Singapore, Singapore
| | - Ruihuan Duan
- School of Material Science and Engineering, Nanyang Technological University, 639798, Singapore, Singapore
- CINTRA CNRS/NTU/THALES, UMI 3288, Research Techno Plaza, Nanyang Technological University, 637371, Singapore, Singapore
| | - Xiaodong Xu
- School of Materials Science and Engineering, Harbin Institute of Technology, 150001, Harbin, China
| | - Fangyuan Sun
- School of Electrical and Electronic Engineering, Nanyang Technological University, 639798, Singapore, Singapore
| | - Wenduo Chen
- School of Electrical and Electronic Engineering, Nanyang Technological University, 639798, Singapore, Singapore
| | - Fakun Wang
- School of Electrical and Electronic Engineering, Nanyang Technological University, 639798, Singapore, Singapore
| | - Siyuan Li
- School of Electrical and Electronic Engineering, Nanyang Technological University, 639798, Singapore, Singapore
| | - Ming Ye
- School of Electrical and Electronic Engineering, Nanyang Technological University, 639798, Singapore, Singapore
| | - Xin Zhou
- Department of Chemistry, National University of Singapore, 117543, Singapore, Singapore
| | - Jinluo Cheng
- GPL Photonics Lab, State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, 130033, Changchun, China
| | - Yao Wu
- School of Material Science and Engineering, Nanyang Technological University, 639798, Singapore, Singapore
| | - Houkun Liang
- School of Electronics and Information Engineering, Sichuan University, 610064, Chengdu, Sichuan, China
| | - Junichiro Kono
- School of Physical and Mathematical Sciences, Nanyang Technological University, 637371, Singapore, Singapore
- Departments of Electrical and Computer Engineering, Physics and Astronomy, and Materials Science and NanoEngineering, Rice University, Houston, TX, USA
| | - Xingji Li
- School of Materials Science and Engineering, Harbin Institute of Technology, 150001, Harbin, China.
| | - Zheng Liu
- School of Material Science and Engineering, Nanyang Technological University, 639798, Singapore, Singapore.
- CINTRA CNRS/NTU/THALES, UMI 3288, Research Techno Plaza, Nanyang Technological University, 637371, Singapore, Singapore.
| | - Qi Jie Wang
- School of Electrical and Electronic Engineering, Nanyang Technological University, 639798, Singapore, Singapore.
- CINTRA CNRS/NTU/THALES, UMI 3288, Research Techno Plaza, Nanyang Technological University, 637371, Singapore, Singapore.
- School of Physical and Mathematical Sciences, Nanyang Technological University, 637371, Singapore, Singapore.
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6
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Liu H, Zhao J, Ly TH. Clean Transfer of Two-Dimensional Materials: A Comprehensive Review. ACS NANO 2024; 18:11573-11597. [PMID: 38655635 DOI: 10.1021/acsnano.4c01000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
The growth of two-dimensional (2D) materials through chemical vapor deposition (CVD) has sparked a growing interest among both the industrial and academic communities. The interest stems from several key advantages associated with CVD, including high yield, high quality, and high tunability. In order to harness the application potentials of 2D materials, it is often necessary to transfer them from their growth substrates to their desired target substrates. However, conventional transfer methods introduce contamination that can adversely affect the quality and properties of the transferred 2D materials, thus limiting their overall application performance. This review presents a comprehensive summary of the current clean transfer methods for 2D materials with a specific focus on the understanding of interaction between supporting layers and 2D materials. The review encompasses various aspects, including clean transfer methods, post-transfer cleaning techniques, and cleanliness assessment. Furthermore, it analyzes and compares the advances and limitations of these clean transfer techniques. Finally, the review highlights the primary challenges associated with current clean transfer methods and provides an outlook on future prospects.
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Affiliation(s)
- Haijun Liu
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong 999077, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China
| | - Jiong Zhao
- Department of Applied Physics, The Hong Kong Polytechnic University, Kowloon, Hong Kong 999077, China
- The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, China
| | - Thuc Hue Ly
- Department of Chemistry and Center of Super-Diamond & Advanced Films (COSDAF), City University of Hong Kong, Kowloon, Hong Kong 999077, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong 999077, China
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7
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Dong W, Dai Z, Liu L, Zhang Z. Toward Clean 2D Materials and Devices: Recent Progress in Transfer and Cleaning Methods. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2303014. [PMID: 38049925 DOI: 10.1002/adma.202303014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 08/30/2023] [Indexed: 12/06/2023]
Abstract
Two-dimensional (2D) materials have tremendous potential to revolutionize the field of electronics and photonics. Unlocking such potential, however, is hampered by the presence of contaminants that usually impede the performance of 2D materials in devices. This perspective provides an overview of recent efforts to develop clean 2D materials and devices. It begins by discussing conventional and recently developed wet and dry transfer techniques and their effectiveness in maintaining material "cleanliness". Multi-scale methodologies for assessing the cleanliness of 2D material surfaces and interfaces are then reviewed. Finally, recent advances in passive and active cleaning strategies are presented, including the unique self-cleaning mechanism, thermal annealing, and mechanical treatment that rely on self-cleaning in essence. The crucial role of interface wetting in these methods is emphasized, and it is hoped that this understanding can inspire further extension and innovation of efficient transfer and cleaning of 2D materials for practical applications.
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Affiliation(s)
- Wenlong Dong
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication and CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhaohe Dai
- Department of Mechanics and Engineering Science, State Key Laboratory for Turbulence and Complex Systems, College of Engineering, Peking University, Beijing, 100871, China
| | - Luqi Liu
- CAS Key Laboratory of Nanosystem and Hierarchical Fabrication and CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China
| | - Zhong Zhang
- CAS Key Laboratory of Mechanical Behavior and Design of Materials, Department of Modern Mechanics, University of Science and Technology of China, Hefei, 230027, China
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8
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Ramezani F, Strasbourg M, Parvez S, Saxena R, Jariwala D, Borys NJ, Whitaker BM. Predicting quantum emitter fluctuations with time-series forecasting models. Sci Rep 2024; 14:6920. [PMID: 38519600 PMCID: PMC10959974 DOI: 10.1038/s41598-024-56517-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 03/07/2024] [Indexed: 03/25/2024] Open
Abstract
2D materials have important fundamental properties allowing for their use in many potential applications, including quantum computing. Various Van der Waals materials, including Tungsten disulfide (WS2), have been employed to showcase attractive device applications such as light emitting diodes, lasers and optical modulators. To maximize the utility and value of integrated quantum photonics, the wavelength, polarization and intensity of the photons from a quantum emission (QE) must be stable. However, random variation of emission energy, caused by the inhomogeneity in the local environment, is a major challenge for all solid-state single photon emitters. In this work, we assess the random nature of the quantum fluctuations, and we present time series forecasting deep learning models to analyse and predict QE fluctuations for the first time. Our trained models can roughly follow the actual trend of the data and, under certain data processing conditions, can predict peaks and dips of the fluctuations. The ability to anticipate these fluctuations will allow physicists to harness quantum fluctuation characteristics to develop novel scientific advances in quantum computing that will greatly benefit quantum technologies.
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Affiliation(s)
- Fereshteh Ramezani
- Electrical and Computer Engineering Department, Montana State University, Bozeman, USA.
| | | | - Sheikh Parvez
- Department of Physics, Montana State University, Bozeman, USA
- Materials Science Program, Montana State University, Bozeman, USA
| | - Ravindra Saxena
- Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, USA
| | - Deep Jariwala
- Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, USA
| | - Nicholas J Borys
- Department of Physics, Montana State University, Bozeman, USA
- Materials Science Program, Montana State University, Bozeman, USA
- Optical Technology Center, Montana State University, Bozeman, USA
| | - Bradley M Whitaker
- Electrical and Computer Engineering Department, Montana State University, Bozeman, USA
- Optical Technology Center, Montana State University, Bozeman, USA
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9
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Syong WR, Fu JH, Kuo YH, Chu YC, Hakami M, Peng TY, Lynch J, Jariwala D, Tung V, Lu YJ. Enhanced Photogating Gain in Scalable MoS 2 Plasmonic Photodetectors via Resonant Plasmonic Metasurfaces. ACS NANO 2024. [PMID: 38315422 DOI: 10.1021/acsnano.3c10390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
Absorption of photons in atomically thin materials has become a challenge in the realization of ultrathin, high-performance optoelectronics. While numerous schemes have been used to enhance absorption in 2D semiconductors, such enhanced device performance in scalable monolayer photodetectors remains unattained. Here, we demonstrate wafer-scale integration of monolayer single-crystal MoS2 photodetectors with a nitride-based resonant plasmonic metasurface to achieve a high detectivity of 2.58 × 1012 Jones with a record-low dark current of 8 pA and long-term stability over 40 days. Upon comparison with control devices, we observe an overall enhancement factor of >100; this can be attributed to the local strong EM field enhanced photogating effect by the resonant plasmonic metasurface. Considering the compatibility of 2D semiconductors and hafnium nitride with the Si CMOS process and their scalability across wafer sizes, our results facilitate the smooth incorporation of 2D semiconductor-based photodetectors into the fields of imaging, sensing, and optical communication applications.
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Affiliation(s)
- Wei-Ren Syong
- Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan
| | - Jui-Han Fu
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan
| | - Yu-Hsin Kuo
- Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan
| | - Yu-Cheng Chu
- Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Mariam Hakami
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan
| | - Tzu-Yu Peng
- Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Jason Lynch
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Deep Jariwala
- Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Vincent Tung
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan
| | - Yu-Jung Lu
- Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan
- Department of Physics, National Taiwan University, Taipei 10617, Taiwan
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10
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Katiyar AK, Hoang AT, Xu D, Hong J, Kim BJ, Ji S, Ahn JH. 2D Materials in Flexible Electronics: Recent Advances and Future Prospectives. Chem Rev 2024; 124:318-419. [PMID: 38055207 DOI: 10.1021/acs.chemrev.3c00302] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
Flexible electronics have recently gained considerable attention due to their potential to provide new and innovative solutions to a wide range of challenges in various electronic fields. These electronics require specific material properties and performance because they need to be integrated into a variety of surfaces or folded and rolled for newly formatted electronics. Two-dimensional (2D) materials have emerged as promising candidates for flexible electronics due to their unique mechanical, electrical, and optical properties, as well as their compatibility with other materials, enabling the creation of various flexible electronic devices. This article provides a comprehensive review of the progress made in developing flexible electronic devices using 2D materials. In addition, it highlights the key aspects of materials, scalable material production, and device fabrication processes for flexible applications, along with important examples of demonstrations that achieved breakthroughs in various flexible and wearable electronic applications. Finally, we discuss the opportunities, current challenges, potential solutions, and future investigative directions about this field.
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Affiliation(s)
- Ajit Kumar Katiyar
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Anh Tuan Hoang
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Duo Xu
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Juyeong Hong
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Beom Jin Kim
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Seunghyeon Ji
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Jong-Hyun Ahn
- School of Electrical and Electronic Engineering, Yonsei University, Seoul 03722, Republic of Korea
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11
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Ding S, Liu C, Li Z, Lu Z, Tao Q, Lu D, Chen Y, Tong W, Liu L, Li W, Ma L, Yang X, Xiao Z, Wang Y, Liao L, Liu Y. Ag-Assisted Dry Exfoliation of Large-Scale and Continuous 2D Monolayers. ACS NANO 2024; 18:1195-1203. [PMID: 38153837 DOI: 10.1021/acsnano.3c11573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2023]
Abstract
Two-dimensional (2D) semiconductors have generated considerable attention for high-performance electronics and optoelectronics. However, to date, it is still challenging to mechanically exfoliate large-area and continuous monolayers while retaining their intrinsic properties. Here, we report a simple dry exfoliation approach to produce large-scale and continuous 2D monolayers by using a Ag film as the peeling tape. Importantly, the conducting Ag layer could be converted into AgOx nanoparticles at low annealing temperature, directly decoupling the conducting Ag with the underlayer 2D monolayers without involving any solution or etching process. Electrical characterization of the monolayer MoS2 transistor shows a decent carrier mobility of 42 cm2 V-1 s-1 and on-state current of 142 μA/μm. Finally, a plasmonic enhancement photodetector could be simultaneously realized due to the direct formation of Ag nanoparticles arrays on MoS2 monolayers, without complex approaches for nanoparticle synthesis and integration processes, demonstrating photoresponsivity and detectivity of 6.3 × 105 A/W and 2.3 × 1013 Jones, respectively.
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Affiliation(s)
- Shuimei Ding
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Chang Liu
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Zhiwei Li
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Zheyi Lu
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Quanyang Tao
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Donglin Lu
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Yang Chen
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Wei Tong
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Liting Liu
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Wanying Li
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Likuan Ma
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Xiaokun Yang
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Zhaojing Xiao
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Yiliu Wang
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Lei Liao
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Yuan Liu
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
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12
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Liao L, Kovalska E, Regner J, Song Q, Sofer Z. Two-Dimensional Van Der Waals Thin Film and Device. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2303638. [PMID: 37731156 DOI: 10.1002/smll.202303638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 08/07/2023] [Indexed: 09/22/2023]
Abstract
In the rapidly evolving field of thin-film electronics, the emergence of large-area flexible and wearable devices has been a significant milestone. Although organic semiconductor thin films, which can be manufactured through solution processing, have been identified, their utility is often undermined by their poor stability and low carrier mobility under ambient conditions. However, inorganic nanomaterials can be solution-processed and demonstrate outstanding intrinsic properties and structural stability. In particular, a series of two-dimensional (2D) nanosheet/nanoparticle materials have been shown to form stable colloids in their respective solvents. However, the integration of these 2D nanomaterials into continuous large-area thin with precise control of layer thickness and lattice orientation still remains a significant challenge. This review paper undertakes a detailed analysis of van der Waals thin films, derived from 2D materials, in the advancement of thin-film electronics and optoelectronic devices. The superior intrinsic properties and structural stability of inorganic nanomaterials are highlighted, which can be solution-processed and underscor the importance of solution-based processing, establishing it as a cornerstone strategy for scalable electronic and optoelectronic applications. A comprehensive exploration of the challenges and opportunities associated with the utilization of 2D materials for the next generation of thin-film electronics and optoelectronic devices is presented.
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Affiliation(s)
- Liping Liao
- Department of Inorganic Chemistry, University of Chemistry and Technology, Technicka 5, Prague, 166 28, Czech Republic
| | - Evgeniya Kovalska
- Faculty of Environment, Science and Economy, Department of Engineering, Exeter, EX4 4QF, UK
| | - Jakub Regner
- Department of Inorganic Chemistry, University of Chemistry and Technology, Technicka 5, Prague, 166 28, Czech Republic
| | - Qunliang Song
- School of Materials and Energy, Southwest University, Chongqing, 400715, P. R. China
| | - Zdeněk Sofer
- Department of Inorganic Chemistry, University of Chemistry and Technology, Technicka 5, Prague, 166 28, Czech Republic
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13
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Xu K, Holbrook M, Holtzman LN, Pasupathy AN, Barmak K, Hone JC, Rosenberger MR. Validating the Use of Conductive Atomic Force Microscopy for Defect Quantification in 2D Materials. ACS NANO 2023; 17:24743-24752. [PMID: 38095969 DOI: 10.1021/acsnano.3c05056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
Defects significantly affect the electronic, chemical, mechanical, and optical properties of two-dimensional (2D) materials. Thus, it is critical to develop a method for convenient and reliable defect quantification. Scanning transmission electron microscopy (STEM) and scanning tunneling microscopy (STM) possess the required atomic resolution but have practical disadvantages. Here, we benchmark conductive atomic force microscopy (CAFM) by a direct comparison with STM in the characterization of transition metal dichalcogenides (TMDs). The results conclusively demonstrate that CAFM and STM image identical defects, giving results that are equivalent both qualitatively (defect appearance) and quantitatively (defect density). Further, we confirm that CAFM can achieve single-atom resolution, similar to that of STM, on both bulk and monolayer samples. The validation of CAFM as a facile and accurate tool for defect quantification provides a routine and reliable measurement that can complement other standard characterization techniques.
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Affiliation(s)
- Kaikui Xu
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Madisen Holbrook
- Department of Physics, Columbia University, New York, New York 10027, United States
| | - Luke N Holtzman
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
| | - Abhay N Pasupathy
- Department of Physics, Columbia University, New York, New York 10027, United States
| | - Katayun Barmak
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
| | - James C Hone
- Department of Mechanical Engineering, Columbia University, New York, New York 10027, United States
| | - Matthew R Rosenberger
- Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
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14
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Cheon CY, Sun Z, Cao J, Gonzalez Marin JF, Tripathi M, Watanabe K, Taniguchi T, Luisier M, Kis A. Disorder-induced bulk photovoltaic effect in a centrosymmetric van der Waals material. NPJ 2D MATERIALS AND APPLICATIONS 2023; 7:74. [PMID: 38665484 PMCID: PMC11041738 DOI: 10.1038/s41699-023-00435-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 10/17/2023] [Indexed: 04/28/2024]
Abstract
Sunlight is widely seen as one of the most abundant forms of renewable energy, with photovoltaic cells based on pn junctions being the most commonly used platform attempting to harness it. Unlike in conventional photovoltaic cells, the bulk photovoltaic effect (BPVE) allows for the generation of photocurrent and photovoltage in a single material without the need to engineer a pn junction and create a built-in electric field, thus offering a solution that can potentially exceed the Shockley-Queisser efficiency limit. However, it requires a material with no inversion symmetry and is therefore absent in centrosymmetric materials. Here, we demonstrate that breaking the inversion symmetry by structural disorder can induce BPVE in ultrathin PtSe2, a centrosymmetric semiconducting van der Waals material. Homogenous illumination of defective PtSe2 by linearly and circularly polarized light results in a photoresponse termed as linear photogalvanic effect (LPGE) and circular photogalvanic effect (CPGE), which is mostly absent in the pristine crystal. First-principles calculations reveal that LPGE originates from Se vacancies that act as asymmetric scattering centers for the photo-generated electron-hole pairs. Our work emphasizes the importance of defects to induce photovoltaic functionality in centrosymmetric materials and shows how the range of materials suitable for light sensing and energy-harvesting applications can be extended.
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Affiliation(s)
- Cheol-Yeon Cheon
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Zhe Sun
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Jiang Cao
- Integrated Systems Laboratory, ETH Zürich, 8092 Zurich, Switzerland
| | - Juan Francisco Gonzalez Marin
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Mukesh Tripathi
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044 Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044 Japan
| | - Mathieu Luisier
- Integrated Systems Laboratory, ETH Zürich, 8092 Zurich, Switzerland
| | - Andras Kis
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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15
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Huang X, Han X, Dai Y, Xu X, Zhang Y, Tian X, Yuan Z, Xing J, Wang Y, Huang Y. Recent Progress in Two-Dimensional Material Exfoliation Technology and Enlightenment for Geological Sciences. J Phys Chem Lett 2023; 14:10181-10193. [PMID: 37930076 DOI: 10.1021/acs.jpclett.3c01683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2023]
Abstract
Mechanical exfoliation technology is vital for the development of two-dimensional (2D) materials. This technology has also facilitated the verification of the performance of electronic and optical devices made from 2D materials. In this Perspective, we provide an overview of exfoliation techniques and highlight key physical properties. Additionally, we explored the chemical instability of certain 2D materials and proposed practical solutions to enhance their stability. Furthermore, we discuss the advantages of suspended 2D materials, which demonstrate improved compatibility and properties compared to nonsuspended materials. A particularly intriguing aspect of this Perspective is the exploration of the similarities between the Earth's crust and 2D materials, offering insights into the formation mechanisms of geological phenomena. In this context, 2D materials may serve as simulators for studying geological processes. We hope that this Perspective stimulates further research into exfoliation technology and the physical/chemical properties of 2D materials while providing new inspiration for earth science investigations.
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Affiliation(s)
- Xinyu Huang
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing 100081, China
| | - Xu Han
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing 100081, China
| | - Yunyun Dai
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing 100081, China
| | - Xiaolong Xu
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing 100081, China
| | - Yan Zhang
- Key Laboratory of Shale Gas and Geoengineering, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Xiaobo Tian
- Key Laboratory of Shale Gas and Geoengineering, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
| | - Zhengyi Yuan
- China Earthquake Networks Center, Beijing 100045, China
| | - Jie Xing
- School of Science, China University of Geosciences, Beijing 100083, China
| | - Yeliang Wang
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing 100081, China
- BIT Chongqing Institute of Microelectronics and Microsystems, Chongqing 100190, China
| | - Yuan Huang
- Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China
- School of Integrated Circuits and Electronics, MIIT Key Laboratory for Low-Dimensional Quantum Structure and Devices, Beijing Institute of Technology, Beijing 100081, China
- BIT Chongqing Institute of Microelectronics and Microsystems, Chongqing 100190, China
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16
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Lee H, Kim H, Kim K, Jeong K, Leem M, Park S, Kang J, Yeom G, Kim H. Three-Dimensional Surface Treatment of MoS 2 Using BCl 3 Plasma-Derived Radicals. ACS APPLIED MATERIALS & INTERFACES 2023; 15:46513-46519. [PMID: 37729007 DOI: 10.1021/acsami.3c09311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
The realization of next-generation gate-all-around field-effect transistors (FETs) using two-dimensional transition metal dichalcogenide (TMDC) semiconductors necessitates the exploration of a three-dimensional (3D) and damage-free surface treatment method to achieve uniform atomic layer-deposition (ALD) of a high-k dielectric film on the inert surface of a TMDC channel. This study developed a BCl3 plasma-derived radical treatment for MoS2 to functionalize MoS2 surfaces for the subsequent ALD of an ultrathin Al2O3 film. Microstructural verification demonstrated a complete coverage of an approximately 2 nm-thick Al2O3 film on a planar MoS2 surface, and the applicability of the technique to 3D structures was confirmed using a suspended MoS2 channel floating from the substrate. Density functional theory calculations supported by optical emission spectroscopy and X-ray photoelectron spectroscopy measurements revealed that BCl radicals, predominantly generated by the BCl3 plasma, adsorbed on MoS2 and facilitated the uniform nucleation of ultrathin ALD-Al2O3 films. Raman and photoluminescence measurements of monolayer MoS2 and electrical measurements of a bottom-gated FET confirmed negligible damage caused by the BCl3 plasma-derived radical treatment. Finally, the successful operation of a top-gated FET with an ultrathin ALD-Al2O3 (∼5 nm) gate dielectric film was demonstrated, indicating the effectiveness of the pretreatment.
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Affiliation(s)
- Heesoo Lee
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Hoijoon Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Kihyun Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Kwangsik Jeong
- Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Republic of Korea
| | - Mirine Leem
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Seunghyun Park
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Jieun Kang
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Geunyoung Yeom
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Hyoungsub Kim
- School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea
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17
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Adam J, Singh M, Abduvakhidov A, Del Sorbo MR, Feoli C, Hussain F, Kaur J, Mirabella A, Rossi M, Sasso A, Valadan M, Varra M, Rusciano G, Altucci C. The Effectiveness of Cyrene as a Solvent in Exfoliating 2D TMDs Nanosheets. Int J Mol Sci 2023; 24:10450. [PMID: 37445624 DOI: 10.3390/ijms241310450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 06/09/2023] [Accepted: 06/16/2023] [Indexed: 07/15/2023] Open
Abstract
The pursuit of environmentally friendly solvents has become an essential research topic in sustainable chemistry and nanomaterial science. With the need to substitute toxic solvents in nanofabrication processes becoming more pressing, the search for alternative solvents has taken on a crucial role in this field. Additionally, the use of toxic, non-economical organic solvents, such as N-methyl-2 pyrrolidone and dimethylformamide, is not suitable for all biomedical applications, even though these solvents are often considered as the best exfoliating agents for nanomaterial fabrication. In this context, the success of producing two-dimensional transition metal dichalcogenides (2D TMDs), such as MoS2 and WS2, with excellent captivating properties is due to the ease of synthesis based on environment-friendly, benign methods with fewer toxic chemicals involved. Herein, we report for the first time on the use of cyrene as an exfoliating agent to fabricate monolayer and few-layered 2D TMDs with a versatile, less time-consuming liquid-phase exfoliation technique. This bio-derived, aprotic, green and eco-friendly solvent produced a stable, surfactant-free, concentrated 2D TMD dispersion with very interesting features, as characterized by UV-visible and Raman spectroscopies. The surface charge and morphology of the fabricated nanoflakes were analyzed using ς-potential and scanning electron microscopy. The study demonstrates that cyrene is a promising green solvent for the exfoliation of 2D TMD nanosheets with potential advantages over traditional organic solvents. The ability to produce smaller-sized-especially in the case of WS2 as compared to MoS2-and mono/few-layered nanostructures with higher negative surface charge values makes cyrene a promising candidate for various biomedical and electronic applications. Overall, the study contributes to the development of sustainable and environmentally friendly methods for the production of 2D nanomaterials for various applications.
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Affiliation(s)
- Jaber Adam
- Department of Physics "Ettore Pancini", University of Naples "Federico II", 80131 Naples, Italy
| | - Manjot Singh
- Department of Advanced Biomedical Sciences, University of Naples "Federico II", 80131 Naples, Italy
- Italy National Institute of Nuclear Physics, Naples Section, 80126 Naples, Italy
| | | | - Maria Rosaria Del Sorbo
- Department of Precision Medicine, Università degli Studi della Campania "L. Vanvitelli", 80138 Naples, Italy
| | - Chiara Feoli
- Department of Advanced Biomedical Sciences, University of Naples "Federico II", 80131 Naples, Italy
| | - Fida Hussain
- Department of Physics "Ettore Pancini", University of Naples "Federico II", 80131 Naples, Italy
| | - Jasneet Kaur
- Department of Physics "Ettore Pancini", University of Naples "Federico II", 80131 Naples, Italy
| | - Antonia Mirabella
- Department of Advanced Biomedical Sciences, University of Naples "Federico II", 80131 Naples, Italy
- Department of Agricultural Sciences, University of Naples "Federico II", 80131 Naples, Italy
| | - Manuela Rossi
- Department of Earth Science, Environment and Resources, University of Naples "Federico II", 80131 Naples, Italy
- Istituto di Cristallografia-CNR, Via G. Amendola 122/O, 70126 Bari, Italy
| | - Antonio Sasso
- Department of Physics "Ettore Pancini", University of Naples "Federico II", 80131 Naples, Italy
| | - Mohammadhassan Valadan
- Department of Advanced Biomedical Sciences, University of Naples "Federico II", 80131 Naples, Italy
- Italy National Institute of Nuclear Physics, Naples Section, 80126 Naples, Italy
| | - Michela Varra
- Department of Pharmacy, University of Naples "Federico II", 80131 Naples, Italy
| | - Giulia Rusciano
- Department of Physics "Ettore Pancini", University of Naples "Federico II", 80131 Naples, Italy
| | - Carlo Altucci
- Department of Advanced Biomedical Sciences, University of Naples "Federico II", 80131 Naples, Italy
- Italy National Institute of Nuclear Physics, Naples Section, 80126 Naples, Italy
- ISASI-CNR, Institute of Applied Sciences and Intelligent Systems "Eduardo Caianiello", 80078 Naples, Italy
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18
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Grubišić-Čabo A, Michiardi M, Sanders CE, Bianchi M, Curcio D, Phuyal D, Berntsen MH, Guo Q, Dendzik M. In Situ Exfoliation Method of Large-Area 2D Materials. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023:e2301243. [PMID: 37236159 PMCID: PMC10401183 DOI: 10.1002/advs.202301243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Indexed: 05/28/2023]
Abstract
2D materials provide a rich platform to study novel physical phenomena arising from quantum confinement of charge carriers. Many of these phenomena are discovered by surface sensitive techniques, such as photoemission spectroscopy, that work in ultra-high vacuum (UHV). Success in experimental studies of 2D materials, however, inherently relies on producing adsorbate-free, large-area, high-quality samples. The method that yields 2D materials of highest quality is mechanical exfoliation from bulk-grown samples. However, as this technique is traditionally performed in a dedicated environment, the transfer of samples into vacuum requires surface cleaning that might diminish the quality of the samples. In this article, a simple method for in situ exfoliation directly in UHV is reported, which yields large-area, single-layered films. Multiple metallic and semiconducting transition metal dichalcogenides are exfoliated in situ onto Au, Ag, and Ge. The exfoliated flakes are found to be of sub-millimeter size with excellent crystallinity and purity, as supported by angle-resolved photoemission spectroscopy, atomic force microscopy, and low-energy electron diffraction. The approach is well-suited for air-sensitive 2D materials, enabling the study of a new suite of electronic properties. In addition, the exfoliation of surface alloys and the possibility of controlling the substrate-2D material twist angle is demonstrated.
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Affiliation(s)
- Antonija Grubišić-Čabo
- Zernike Institute for Advanced Materials, University of Groningen, Groningen, 9747 AG, The Netherlands
- Department of Applied Physics, KTH Royal Institute of Technology, Hannes Alfvéns väg 12, Stockholm, 114 19, Sweden
| | - Matteo Michiardi
- Quantum Matter Institute, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, V6T 1Z1, Canada
| | - Charlotte E Sanders
- Central Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Campus, Didcot, 0X11 0QX, UK
| | - Marco Bianchi
- School of Physics and Astronomy, Aarhus University, Aarhus, 8000 C, Denmark
| | - Davide Curcio
- School of Physics and Astronomy, Aarhus University, Aarhus, 8000 C, Denmark
| | - Dibya Phuyal
- Department of Applied Physics, KTH Royal Institute of Technology, Hannes Alfvéns väg 12, Stockholm, 114 19, Sweden
| | - Magnus H Berntsen
- Department of Applied Physics, KTH Royal Institute of Technology, Hannes Alfvéns väg 12, Stockholm, 114 19, Sweden
| | - Qinda Guo
- Department of Applied Physics, KTH Royal Institute of Technology, Hannes Alfvéns väg 12, Stockholm, 114 19, Sweden
| | - Maciej Dendzik
- Department of Applied Physics, KTH Royal Institute of Technology, Hannes Alfvéns väg 12, Stockholm, 114 19, Sweden
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19
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Moon JY, Kim SI, Josline MJ, Kim CY, Kim JS, Kim I, Jung E, Lee JH. Protocol for preparing layer-engineered van der Waals materials through atomic spalling. STAR Protoc 2023; 4:102228. [PMID: 37071528 DOI: 10.1016/j.xpro.2023.102228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Revised: 02/28/2023] [Accepted: 03/16/2023] [Indexed: 04/19/2023] Open
Abstract
Here, we present a protocol for preparing layer-engineered van der Waals (vdW) materials via an atomic spalling process. We describe steps for fixing bulk crystals and introduce the appropriate stressor materials. We then detail a deposition technique for internal stress regulation of stressor film, followed by layer-engineered atomic-scale spalling to exfoliate vdW materials with a controlled number of layers from bulk crystals. Lastly, we outline a procedure for polymer/stressor film removal. For complete details on the use and execution of this protocol, please refer to Moon et al.1.
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Affiliation(s)
- Ji-Yun Moon
- Department of Energy Systems Research, Ajou University, Suwon 16499, Korea; Department of Materials Science and Engineering, Ajou University, Suwon 16499, Korea
| | - Seung-Il Kim
- Department of Energy Systems Research, Ajou University, Suwon 16499, Korea; Department of Materials Science and Engineering, Ajou University, Suwon 16499, Korea
| | | | - Chan Young Kim
- Department of Materials Science and Engineering, Ajou University, Suwon 16499, Korea
| | - Jin Su Kim
- Department of Materials Science and Engineering, Ajou University, Suwon 16499, Korea
| | - Ina Kim
- Department of Advanced Materials Engineering, Kyonggi University, Suwon 16227, Korea
| | - Euna Jung
- Department of Materials Science and Engineering, Ajou University, Suwon 16499, Korea
| | - Jae-Hyun Lee
- Department of Energy Systems Research, Ajou University, Suwon 16499, Korea; Department of Materials Science and Engineering, Ajou University, Suwon 16499, Korea.
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20
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Li Q, Alfrey A, Hu J, Lydick N, Paik E, Liu B, Sun H, Lu Y, Wang R, Forrest S, Deng H. Macroscopic transition metal dichalcogenides monolayers with uniformly high optical quality. Nat Commun 2023; 14:1837. [PMID: 37005420 PMCID: PMC10067954 DOI: 10.1038/s41467-023-37500-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 03/19/2023] [Indexed: 04/04/2023] Open
Abstract
The unique optical properties of transition metal dichalcogenide (TMD) monolayers have attracted significant attention for both photonics applications and fundamental studies of low-dimensional systems. TMD monolayers of high optical quality, however, have been limited to micron-sized flakes produced by low-throughput and labour-intensive processes, whereas large-area films are often affected by surface defects and large inhomogeneity. Here we report a rapid and reliable method to synthesize macroscopic-scale TMD monolayers of uniform, high optical quality. Using 1-dodecanol encapsulation combined with gold-tape-assisted exfoliation, we obtain monolayers with lateral size > 1 mm, exhibiting exciton energy, linewidth, and quantum yield uniform over the whole area and close to those of high-quality micron-sized flakes. We tentatively associate the role of the two molecular encapsulating layers as isolating the TMD from the substrate and passivating the chalcogen vacancies, respectively. We demonstrate the utility of our encapsulated monolayers by scalable integration with an array of photonic crystal cavities, creating polariton arrays with enhanced light-matter coupling strength. This work provides a pathway to achieving high-quality two-dimensional materials over large areas, enabling research and technology development beyond individual micron-sized devices.
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Affiliation(s)
- Qiuyang Li
- Department of Physics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Adam Alfrey
- Department of Physics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Jiaqi Hu
- Applied Physics Program, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Nathanial Lydick
- Department of Physics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Eunice Paik
- Department of Physics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Bin Liu
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Haiping Sun
- Michigan Center for Materials Characterization, College of Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Yang Lu
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Ruoyu Wang
- Department of Physics, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Stephen Forrest
- Department of Physics, University of Michigan, Ann Arbor, MI, 48109, USA
- Applied Physics Program, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Hui Deng
- Department of Physics, University of Michigan, Ann Arbor, MI, 48109, USA.
- Applied Physics Program, University of Michigan, Ann Arbor, MI, 48109, USA.
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21
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Xing F, Ji G, Li Z, Zhong W, Wang F, Liu Z, Xin W, Tian J. Preparation, properties and applications of two-dimensional superlattices. MATERIALS HORIZONS 2023; 10:722-744. [PMID: 36562255 DOI: 10.1039/d2mh01206e] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
As a combination concept of a 2D material and a superlattice, two-dimensional superlattices (2DSs) have attracted increasing attention recently. The natural advantages of 2D materials in their properties, dimension, diversity and compatibility, and their gradually improved technologies for preparation and device fabrication serve as solid foundations for the development of 2DSs. Compared with the existing 2D materials and even their heterostructures, 2DSs relate to more materials and elaborate architectures, leading to novel systems with more degrees of freedom to modulate material properties at the nanoscale. Here, three typical types of 2DSs, including the component, strain-induced and moiré superlattices, are reviewed. The preparation methods, properties and state-of-the-art applications of each type are summarized. An outlook of the challenges and future developments is also presented. We hope that this work can provide a reference for the development of 2DS-related research.
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Affiliation(s)
- Fei Xing
- School of Physics and Optoelectronic Engineering, Shandong University of Technology, Zibo, 255049, China
| | - Guangmin Ji
- School of Physics and Optoelectronic Engineering, Shandong University of Technology, Zibo, 255049, China
| | - Zongwen Li
- School of Physics and Optoelectronic Engineering, Shandong University of Technology, Zibo, 255049, China
| | - Weiheng Zhong
- Key Laboratory of UV-Emitting Materials and Technology, Ministry of Education, Northeast Normal University, Changchun, 130024, China.
| | - Feiyue Wang
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Electronics and Information Technology, Sun Yat-sen University, Guangzhou, 510275, China
| | - Zhibo Liu
- Key Laboratory of Weak Light Nonlinear Photonics, Ministry of Education, Teda Applied Physics Institute and School of Physics, Nankai University, Tianjin, 300071, China.
| | - Wei Xin
- Key Laboratory of UV-Emitting Materials and Technology, Ministry of Education, Northeast Normal University, Changchun, 130024, China.
| | - Jianguo Tian
- Key Laboratory of Weak Light Nonlinear Photonics, Ministry of Education, Teda Applied Physics Institute and School of Physics, Nankai University, Tianjin, 300071, China.
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22
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Kim JY, Ju X, Ang KW, Chi D. Van der Waals Layer Transfer of 2D Materials for Monolithic 3D Electronic System Integration: Review and Outlook. ACS NANO 2023; 17:1831-1844. [PMID: 36655854 DOI: 10.1021/acsnano.2c10737] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Two-dimensional materials (2DMs) have attracted a great deal of interest due to their immense potential for scientific breakthroughs and technological innovations. While some 2D transition metal dichalcogenides (TMDC) such as MoS2 and WS2 are considered as the ultimate channel materials in unltrascaled transistors as replacements for Si, there has also been increasing interest in the monolithic 3D integration of 2DMs on the Si CMOS platform or in flexible electronics as back-end-of-line transistors, memory devices/selectors, and sensors, taking advantage of 2DM properties such as a high current driving capability with low leakage current, nonvolatile switching characteristics, a large surface-to-volume ratio, and a tunable bandgap. However, the realization of both of these scenarios critically depends on the development of manufacturing-viable high-yield 2DM layers transfer from the growth substrate to the Si, since the growth of high-quality 2DM layers often requires a high-temperature growth process on template substrates. Motivated by this, extensive efforts have been made by the 2DM research community to develop various 2DM layer transfer methods, leveraging the van der Waals transfer capability of the layer-structured 2DMs. These efforts have led to a number of successful demonstrations of wafer-scale 2D TMDC layer transfer, while 2DM-enabled template growth/transfer of some functional bulk materials such as III-V, Ge, and AlN has also been demonstrated. This review surveys and compares different 2DM transfer methods developed recently, with a focus on large-area 2D TMDC film transfer along with an introduction of 2DM template-assisted van der Waals growth/transfer of non-2D thin films. We will also briefly present an outlook of our envisioned multifunctionalities in 3D integrated electronic systems enabled by monolithic 3D integration of 2DMs and III-V via van der Waals transfer and discuss possible technology options for overcoming remaining challenges.
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Affiliation(s)
- Jun-Young Kim
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 2 Fusionopolis Way, Singapore 138634, Singapore
| | - Xin Ju
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 2 Fusionopolis Way, Singapore 138634, Singapore
| | - Kah-Wee Ang
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 2 Fusionopolis Way, Singapore 138634, Singapore
- Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, Singapore
| | - Dongzhi Chi
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 2 Fusionopolis Way, Singapore 138634, Singapore
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23
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Li M, Yin B, Gao C, Guo J, Zhao C, Jia C, Guo X. Graphene: Preparation, tailoring, and modification. EXPLORATION (BEIJING, CHINA) 2023; 3:20210233. [PMID: 37323621 PMCID: PMC10190957 DOI: 10.1002/exp.20210233] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 07/05/2022] [Indexed: 06/17/2023]
Abstract
Graphene is a 2D material with fruitful electrical properties, which can be efficiently prepared, tailored, and modified for a variety of applications, particularly in the field of optoelectronic devices thanks to its planar hexagonal lattice structure. To date, graphene has been prepared using a variety of bottom-up growth and top-down exfoliation techniques. To prepare high-quality graphene with high yield, a variety of physical exfoliation methods, such as mechanical exfoliation, anode bonding exfoliation, and metal-assisted exfoliation, have been developed. To adjust the properties of graphene, different tailoring processes have been emerged to precisely pattern graphene, such as gas etching and electron beam lithography. Due to the differences in reactivity and thermal stability of different regions, anisotropic tailoring of graphene can be achieved by using gases as the etchant. To meet practical requirements, further chemical functionalization at the edge and basal plane of graphene has been extensively utilized to modify its properties. The integration and application of graphene devices is facilitated by the combination of graphene preparation, tailoring, and modification. This review focuses on several important strategies for graphene preparation, tailoring, and modification that have recently been developed, providing a foundation for its potential applications.
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Affiliation(s)
- Mingyao Li
- Beijing National Laboratory for Molecular Sciences, National Biomedical Imaging Center, College of Chemistry and Molecular EngineeringPeking UniversityBeijingChina
| | - Bing Yin
- Beijing National Laboratory for Molecular Sciences, National Biomedical Imaging Center, College of Chemistry and Molecular EngineeringPeking UniversityBeijingChina
| | - Chunyan Gao
- Center of Single‐Molecule Sciences, Institute of Modern Optics, Tianjin Key Laboratory of Micro‐scale Optical Information Science and Technology, Frontiers Science Center for New Organic Matter, College of Electronic Information and Optical EngineeringNankai UniversityTianjinChina
| | - Jie Guo
- Center of Single‐Molecule Sciences, Institute of Modern Optics, Tianjin Key Laboratory of Micro‐scale Optical Information Science and Technology, Frontiers Science Center for New Organic Matter, College of Electronic Information and Optical EngineeringNankai UniversityTianjinChina
| | - Cong Zhao
- Center of Single‐Molecule Sciences, Institute of Modern Optics, Tianjin Key Laboratory of Micro‐scale Optical Information Science and Technology, Frontiers Science Center for New Organic Matter, College of Electronic Information and Optical EngineeringNankai UniversityTianjinChina
| | - Chuancheng Jia
- Beijing National Laboratory for Molecular Sciences, National Biomedical Imaging Center, College of Chemistry and Molecular EngineeringPeking UniversityBeijingChina
- Center of Single‐Molecule Sciences, Institute of Modern Optics, Tianjin Key Laboratory of Micro‐scale Optical Information Science and Technology, Frontiers Science Center for New Organic Matter, College of Electronic Information and Optical EngineeringNankai UniversityTianjinChina
| | - Xuefeng Guo
- Beijing National Laboratory for Molecular Sciences, National Biomedical Imaging Center, College of Chemistry and Molecular EngineeringPeking UniversityBeijingChina
- Center of Single‐Molecule Sciences, Institute of Modern Optics, Tianjin Key Laboratory of Micro‐scale Optical Information Science and Technology, Frontiers Science Center for New Organic Matter, College of Electronic Information and Optical EngineeringNankai UniversityTianjinChina
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24
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Liu F. Time- and angle-resolved photoemission spectroscopy (TR-ARPES) of TMDC monolayers and bilayers. Chem Sci 2023; 14:736-750. [PMID: 36755720 PMCID: PMC9890651 DOI: 10.1039/d2sc04124c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 12/04/2022] [Indexed: 12/12/2022] Open
Abstract
Many unique properties in two-dimensional (2D) materials and their heterostructures rely on charge excitation, scattering, transfer, and relaxation dynamics across different points in the momentum space. Understanding these dynamics is crucial in both the fundamental study of 2D physics and their incorporation in optoelectronic and quantum devices. A direct method to probe charge carrier dynamics with momentum resolution is time- and angle-resolved photoemission spectroscopy (TR-ARPES). Such measurements have been challenging, since photoexcited carriers in many 2D monolayers reside at high crystal momenta, requiring probe photon energies in the extreme UV (EUV) regime. These challenges have been recently addressed by development of table-top pulsed EUV sources based on high harmonic generation, and the successful integration into a TR-ARPES and/or time-resolved momentum microscope. Such experiments will allow direct imaging of photoelectrons with superior time, energy, and crystal momentum resolution, with unique advantage over traditional optical measurements. Recently, TR-ARPES experiments of 2D transition metal dichalcogenide (TMDC) monolayers and bilayers have created unprecedented opportunities to reveal many intrinsic dynamics of 2D materials, such as bandgap renormalization, charge carrier scattering, relaxation, and wavefunction localization in moiré patterns. This perspective aims to give a short review of recent discoveries and discuss the challenges and opportunities of such techniques in the future.
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Affiliation(s)
- Fang Liu
- Department of Chemistry and the PULSE Institute, Stanford University Stanford California 94305 USA
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25
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Nguyen V, Li W, Ager J, Xu K, Taylor H. Optical reflectance imaging reveals interlayer coupling in mechanically stacked MoS 2 and WS 2 bilayers. OPTICS EXPRESS 2023; 31:3291-3303. [PMID: 36785325 DOI: 10.1364/oe.473397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 12/13/2022] [Indexed: 06/18/2023]
Abstract
Optical reflectance imaging is a popular technique for characterizing 2D materials, thanks to its simplicity and speed of data acquisition. The use of this method for studying interlayer phenomena in stacked 2D layers has, however, remained limited. Here we demonstrate that optical imaging can reveal the nature of interlayer coupling in stacked MoS2 and WS2 bilayers through their observed reflectance contrast versus the substrate. Successful determination of interlayer coupling requires co-optimization of the illumination wavelength and the thickness of an underlying SiO2 film. Our observations are supported by multilayer optical calculations together with an analysis of the effect of any interlayer gap. This approach promises quick characterization of constructed 2D material systems.
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26
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Guo S, Luo M, Shi G, Tian N, Huang Z, Yang F, Ma L, Wang NZ, Shi Q, Xu K, Xu Z, Watanabe K, Taniguchi T, Chen XH, Shen D, Zhang L, Ruan W, Zhang Y. An ultra-high vacuum system for fabricating clean two-dimensional material devices. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:013903. [PMID: 36725600 DOI: 10.1063/5.0110875] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 12/21/2022] [Indexed: 06/18/2023]
Abstract
High mobility electron gases confined at material interfaces have been a venue for major discoveries in condensed matter physics. Ultra-high vacuum (UHV) technologies played a key role in creating such high-quality interfaces. The advent of two-dimensional (2D) materials brought new opportunities to explore exotic physics in flat lands. UHV technologies may once again revolutionize research in low dimensions by facilitating the construction of ultra-clean interfaces with a wide variety of 2D materials. Here, we describe the design and operation of a UHV 2D material device fabrication system, in which the entire fabrication process is performed under pressure lower than 5 × 10-10 mbar. Specifically, the UHV system enables the exfoliation of atomically clean 2D materials. Subsequent in situ assembly of van der Waals heterostructures produces high-quality interfaces that are free of contamination. We demonstrate functionalities of this system through exemplary fabrication of various 2D materials and their heterostructures.
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Affiliation(s)
- Shuaifei Guo
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200438, China
| | - Mingyan Luo
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200438, China
| | - Gang Shi
- Department of Physics, Southern University of Science and Technology, 518055 Shenzhen, China
| | - Ning Tian
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200438, China
| | - Zhe Huang
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences, Shanghai 200050, China
| | - Fangyuan Yang
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200438, China
| | - Liguo Ma
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200438, China
| | - Nai Zhou Wang
- Hefei National Laboratory for Physical Science at Microscale and Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Qinzhen Shi
- Center for Biomedical Engineering, Fudan University, Shanghai 200438, China
| | - Kailiang Xu
- Center for Biomedical Engineering, Fudan University, Shanghai 200438, China
| | - Zihan Xu
- SixCarbon Technology, Youmagang Industry Park, Shenzhen 518106, China
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Xian Hui Chen
- Hefei National Laboratory for Physical Science at Microscale and Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Dawei Shen
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences, Shanghai 200050, China
| | - Liyuan Zhang
- Department of Physics, Southern University of Science and Technology, 518055 Shenzhen, China
| | - Wei Ruan
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200438, China
| | - Yuanbo Zhang
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200438, China
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27
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Li Z, Rashvand F, Bretscher H, Szydłowska BM, Xiao J, Backes C, Rao A. Understanding the Photoluminescence Quenching of Liquid Exfoliated WS 2 Monolayers. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2022; 126:21681-21688. [PMID: 36605783 PMCID: PMC9806825 DOI: 10.1021/acs.jpcc.2c05284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 11/24/2022] [Indexed: 06/17/2023]
Abstract
Monolayer transition metal dichalcogenides (TMDs) are being investigated as active materials in optoelectronic devices due to their strong excitonic effects. While mechanical exfoliation (ME) of monolayer TMDs is limited to small areas, these materials can also be exfoliated from their parent layered materials via high-volume liquid phase exfoliation (LPE). However, it is currently considered that LPE-synthesized materials show poor optoelectronic performance compared to ME materials, such as poor photoluminescence quantum efficiencies (PLQEs). Here we evaluate the photophysical properties of monolayer-enriched LPE WS2 dispersions via steady-state and time-resolved optical spectroscopy and benchmark these materials against untreated and chemically treated ME WS2 monolayers. We show that the LPE materials show features of high-quality semiconducting materials such as very small Stokes shift, smaller photoluminescence line widths, and longer exciton lifetimes than ME WS2. We reveal that the energy transfer between the direct-gap monolayers and in-direct gap few-layers in LPE WS2 dispersions is a major reason for their quenched PL. Our results suggest that LPE TMDs are not inherently highly defective and could have a high potential for optoelectronic device applications if improved strategies to purify the LPE materials and reduce aggregation could be implemented.
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Affiliation(s)
- Zhaojun Li
- Cavendish
Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE Cambridge, United Kingdom
- Molecular
and Condensed Matter Physics, Department of Physics and Astronomy, Uppsala University, 75120 Uppsala, Sweden
| | - Farnia Rashvand
- Institute
for Physical Chemistry, Ruprecht-Karls-Universität
Heidelberg, Im Neuenheimer
Feld 253, 69120 Heidelberg, Germany
| | - Hope Bretscher
- Cavendish
Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE Cambridge, United Kingdom
| | - Beata M. Szydłowska
- Institute
for Physical Chemistry, Ruprecht-Karls-Universität
Heidelberg, Im Neuenheimer
Feld 253, 69120 Heidelberg, Germany
| | - James Xiao
- Cavendish
Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE Cambridge, United Kingdom
| | - Claudia Backes
- Institute
for Physical Chemistry, Ruprecht-Karls-Universität
Heidelberg, Im Neuenheimer
Feld 253, 69120 Heidelberg, Germany
| | - Akshay Rao
- Cavendish
Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE Cambridge, United Kingdom
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28
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Li Y, Weng S, Niu R, Zhen W, Xu F, Zhu W, Zhang C. Poly(vinyl alcohol)-Assisted Exfoliation of van der Waals Materials. ACS OMEGA 2022; 7:38774-38781. [PMID: 36340140 PMCID: PMC9631881 DOI: 10.1021/acsomega.2c04409] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 10/07/2022] [Indexed: 06/16/2023]
Abstract
We report a highly efficient and easily transferable poly(vinyl alcohol) (PVA)-assisted exfoliation method, which allows one to obtain van der Waals materials on large scales, e.g., centimeter-scale graphite flakes and hundred-micrometer-scale several layers of ZnIn2S4 and BN. The present exfoliation scheme is nondestructive, and the materials prepared by PVA-assisted exfoliation can be directly fabricated into devices. This exfoliation approach could be helpful in overcoming the preparation bottleneck for large-scale applications of two-dimensional (2D) materials.
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Affiliation(s)
- Yaodong Li
- High
Magnetic Field Laboratory of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei230031, China
- University
of Science and Technology of China, Hefei230026, China
| | - Shirui Weng
- High
Magnetic Field Laboratory of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei230031, China
| | - Rui Niu
- High
Magnetic Field Laboratory of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei230031, China
| | - Weili Zhen
- High
Magnetic Field Laboratory of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei230031, China
| | - Feng Xu
- High
Magnetic Field Laboratory of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei230031, China
| | - Wenka Zhu
- High
Magnetic Field Laboratory of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei230031, China
| | - Changjin Zhang
- High
Magnetic Field Laboratory of Anhui Province, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei230031, China
- Institutes
of Physical Science and Information Technology, Anhui University, Hefei230601, China
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29
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Fu Q, Dai J, Huang X, Dai Y, Pan Y, Yang L, Sun Z, Miao T, Zhou M, Zhao L, Zhao W, Han X, Lu J, Gao H, Zhou X, Wang Y, Ni Z, Ji W, Huang Y. One-Step Exfoliation Method for Plasmonic Activation of Large-Area 2D Crystals. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2204247. [PMID: 36104244 PMCID: PMC9661865 DOI: 10.1002/advs.202204247] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Indexed: 06/01/2023]
Abstract
Advanced exfoliation techniques are crucial for exploring the intrinsic properties and applications of 2D materials. Though the recently discovered Au-enhanced exfoliation technique provides an effective strategy for the preparation of large-scale 2D crystals, the high cost of gold hinders this method from being widely adopted in industrial applications. In addition, direct Au contact could significantly quench photoluminescence (PL) emission in 2D semiconductors. It is therefore crucial to find alternative metals that can replace gold to achieve efficient exfoliation of 2D materials. Here, the authors present a one-step Ag-assisted method that can efficiently exfoliate many large-area 2D monolayers, where the yield ratio is comparable to Au-enhanced exfoliation method. Differing from Au film, however, the surface roughness of as-prepared Ag films on SiO2 /Si substrate is much higher, which facilitates the generation of surface plasmons resulting from the nanostructures formed on the rough Ag surface. More interestingly, the strong coupling between 2D semiconductor crystals (e.g., MoS2 , MoSe2 ) and Ag film leads to a unique PL enhancement that has not been observed in other mechanical exfoliation techniques, which can be mainly attributed to enhanced light-matter interaction as a result of extended propagation of surface plasmonic polariton (SPP). This work provides a lower-cost and universal Ag-assisted exfoliation method, while at the same time offering enhanced SPP-matter interactions.
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Affiliation(s)
- Qiang Fu
- Advanced Research Institute of Multidisciplinary ScienceBeijing Institute of TechnologyBeijing100081P. R. China
- School of Physics and Key Laboratory of MEMS of the Ministry of EducationSoutheast UniversityNanjing211189P. R. China
- Institute of PhysicsChinese Academy of ScienceBeijing100190P. R. China
| | - Jia‐Qi Dai
- Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro‐Nano DevicesRenmin University of ChinaBeijing100872P. R. China
| | - Xin‐Yu Huang
- Advanced Research Institute of Multidisciplinary ScienceBeijing Institute of TechnologyBeijing100081P. R. China
| | - Yun‐Yun Dai
- Advanced Research Institute of Multidisciplinary ScienceBeijing Institute of TechnologyBeijing100081P. R. China
| | - Yu‐Hao Pan
- China North Vehicle Research InstituteBeijing100072P. R. China
| | - Long‐Long Yang
- Institute of PhysicsChinese Academy of ScienceBeijing100190P. R. China
| | - Zhen‐Yu Sun
- Institute of PhysicsChinese Academy of ScienceBeijing100190P. R. China
| | - Tai‐Min Miao
- Institute of PhysicsChinese Academy of ScienceBeijing100190P. R. China
| | - Meng‐Fan Zhou
- School of Physics and Key Laboratory of MEMS of the Ministry of EducationSoutheast UniversityNanjing211189P. R. China
| | - Lin Zhao
- Institute of PhysicsChinese Academy of ScienceBeijing100190P. R. China
- Songshan Lake Materials LaboratoryDongguan523808P. R. China
| | - Wei‐Jie Zhao
- School of Physics and Key Laboratory of MEMS of the Ministry of EducationSoutheast UniversityNanjing211189P. R. China
| | - Xu Han
- Advanced Research Institute of Multidisciplinary ScienceBeijing Institute of TechnologyBeijing100081P. R. China
- Institute of PhysicsChinese Academy of ScienceBeijing100190P. R. China
| | - Jun‐Peng Lu
- School of Physics and Key Laboratory of MEMS of the Ministry of EducationSoutheast UniversityNanjing211189P. R. China
| | - Hong‐Jun Gao
- Institute of PhysicsChinese Academy of ScienceBeijing100190P. R. China
- University of Chinese Academy of SciencesBeijing100049P. R. China
| | - Xing‐Jiang Zhou
- Institute of PhysicsChinese Academy of ScienceBeijing100190P. R. China
- Songshan Lake Materials LaboratoryDongguan523808P. R. China
- University of Chinese Academy of SciencesBeijing100049P. R. China
| | - Ye‐Liang Wang
- Advanced Research Institute of Multidisciplinary ScienceBeijing Institute of TechnologyBeijing100081P. R. China
| | - Zhen‐Hua Ni
- School of Physics and Key Laboratory of MEMS of the Ministry of EducationSoutheast UniversityNanjing211189P. R. China
| | - Wei Ji
- Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro‐Nano DevicesRenmin University of ChinaBeijing100872P. R. China
| | - Yuan Huang
- Advanced Research Institute of Multidisciplinary ScienceBeijing Institute of TechnologyBeijing100081P. R. China
- Institute of PhysicsChinese Academy of ScienceBeijing100190P. R. China
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30
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Ma EY, Hu J, Waldecker L, Watanabe K, Taniguchi T, Liu F, Heinz TF. The Reststrahlen Effect in the Optically Thin Limit: A Framework for Resonant Response in Thin Media. NANO LETTERS 2022; 22:8389-8393. [PMID: 36112673 DOI: 10.1021/acs.nanolett.2c02819] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Sharp resonances can strongly modify the electromagnetic response of matter. A classic example is the Reststrahlen effect - high reflectivity in the mid-infrared in many polar crystals near their optical phonon resonances. Although this effect in bulk materials has been studied extensively, a systematic treatment for finite thickness remains challenging. Here we describe, experimentally and theoretically, the Reststrahlen response in hexagonal boron nitride across more than 5 orders of magnitude in thickness, down to a monolayer. We find that the high reflectivity plateau of the Reststrahlen band evolves into a single peak as the material enters the optically thin limit, within which two distinct regimes emerge: a strong-response regime dominated by coherent radiative decay and a weak-response regime dominated by damping. We show that this evolution can be explained by a simple two-dimensional sheet model that can be applied to a wide range of thin media.
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Affiliation(s)
- Eric Y Ma
- Department of Applied Physics, Stanford University, Stanford, California 94305, United States
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Department of Physics, University of California, Berkeley, Berkeley, California 94720, United States
| | - Jenny Hu
- Department of Applied Physics, Stanford University, Stanford, California 94305, United States
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Lutz Waldecker
- Department of Applied Physics, Stanford University, Stanford, California 94305, United States
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- 2nd Institute of Physics, RWTH Aachen University, 52074 Aachen, Germany
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Fang Liu
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Tony F Heinz
- Department of Applied Physics, Stanford University, Stanford, California 94305, United States
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
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31
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Kim JS, Maity N, Kim M, Fu S, Juneja R, Singh A, Akinwande D, Lin JF. Strain-Modulated Interlayer Charge and Energy Transfers in MoS 2/WS 2 Heterobilayer. ACS APPLIED MATERIALS & INTERFACES 2022; 14:46841-46849. [PMID: 36195978 DOI: 10.1021/acsami.2c10982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Excitonic properties in 2D heterobilayers are closely governed by charge transfer (CT) and excitonic energy transfer (ET) at van der Waals interfaces. Various means have been employed to modulate the interlayer CT and ET, including electrical gating and modifying interlayer spacing, but with limited extent in their controllability. Here, we report a novel method to modulate these transfers in the MoS2/WS2 heterobilayer by applying compressive strain under hydrostatic pressure. Raman and photoluminescence measurements, combined with density functional theory calculations, show pressure-enhanced interlayer interaction of the heterobilayer. Heterobilayer-to-monolayer photoluminescence intensity ratio (η) of WS2 decreases by five times up to ≈4 GPa, suggesting enhanced ET, whereas it increases by an order of magnitude at higher pressures and reaches almost unity. Theoretical calculations show that orbital switching and charge transfers in the heterobilayer's hybridized conduction band are responsible for the non-monotonic modulation of the transfers. Our findings provide a compelling approach toward effective mechanical control of CT and ET in 2D excitonic devices.
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Affiliation(s)
- Joon-Seok Kim
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois60208, United States
- Microelectronics Research Center, The University of Texas at Austin, Austin, Texas78758, United States
| | - Nikhilesh Maity
- Materials Research Centre, Indian Institute of Science, Bangalore560012, India
| | - Myungsoo Kim
- Microelectronics Research Center, The University of Texas at Austin, Austin, Texas78758, United States
| | - Suyu Fu
- Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, AustinTexas78712, United States
| | - Rinkle Juneja
- Materials Research Centre, Indian Institute of Science, Bangalore560012, India
| | - Abhishek Singh
- Materials Research Centre, Indian Institute of Science, Bangalore560012, India
| | - Deji Akinwande
- Microelectronics Research Center, The University of Texas at Austin, Austin, Texas78758, United States
| | - Jung-Fu Lin
- Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, AustinTexas78712, United States
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Na J, Park C, Lee CH, Choi WR, Choi S, Lee JU, Yang W, Cheong H, Campbell EEB, Jhang SH. Indirect Band Gap in Scrolled MoS 2 Monolayers. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3353. [PMID: 36234481 PMCID: PMC9565867 DOI: 10.3390/nano12193353] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/14/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
MoS2 nanoscrolls that have inner core radii of ∼250 nm are generated from MoS2 monolayers, and the optical and transport band gaps of the nanoscrolls are investigated. Photoluminescence spectroscopy reveals that a MoS2 monolayer, originally a direct gap semiconductor (∼1.85 eV (optical)), changes into an indirect gap semiconductor (∼1.6 eV) upon scrolling. The size of the indirect gap for the MoS2 nanoscroll is larger than that of a MoS2 bilayer (∼1.54 eV), implying a weaker interlayer interaction between concentric layers of the MoS2 nanoscroll compared to Bernal-stacked MoS2 few-layers. Transport measurements on MoS2 nanoscrolls incorporated into ambipolar ionic-liquid-gated transistors yielded a band gap of ∼1.9 eV. The difference between the transport and optical gaps indicates an exciton binding energy of 0.3 eV for the MoS2 nanoscrolls. The rolling up of 2D atomic layers into nanoscrolls introduces a new type of quasi-1D nanostructure and provides another way to modify the band gap of 2D materials.
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Affiliation(s)
- Jeonghyeon Na
- School of Physics, Konkuk University, Seoul 05029, Korea
| | - Changyeon Park
- School of Physics, Konkuk University, Seoul 05029, Korea
| | - Chang Hoi Lee
- School of Physics, Konkuk University, Seoul 05029, Korea
| | - Won Ryeol Choi
- School of Physics, Konkuk University, Seoul 05029, Korea
| | - Sooho Choi
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Suwon 16419, Korea
| | - Jae-Ung Lee
- Department of Physics, Ajou University, Suwon 16499, Korea
| | - Woochul Yang
- Department of Physics, Dongguk University, Seoul 04620, Korea
| | - Hyeonsik Cheong
- Department of Physics, Sogang University, Seoul 04107, Korea
| | - Eleanor E. B. Campbell
- EaStCHEM, School of Chemistry, Edinburgh University, David Brewster Road, Edinburgh EH9 3FJ, UK
- Department of Physics, Ehwa Womans University, Seoul 03760, Korea
| | - Sung Ho Jhang
- School of Physics, Konkuk University, Seoul 05029, Korea
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Li H, Xiong X, Hui F, Yang D, Jiang J, Feng W, Han J, Duan J, Wang Z, Sun L. Constructing van der Waals heterostructures by dry-transfer assembly for novel optoelectronic device. NANOTECHNOLOGY 2022; 33:465601. [PMID: 35313295 DOI: 10.1088/1361-6528/ac5f96] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 03/21/2022] [Indexed: 06/14/2023]
Abstract
Since the first successful exfoliation of graphene, the superior physical and chemical properties of two-dimensional (2D) materials, such as atomic thickness, strong in-plane bonding energy and weak inter-layer van der Waals (vdW) force have attracted wide attention. Meanwhile, there is a surge of interest in novel physics which is absent in bulk materials. Thus, vertical stacking of 2D materials could be critical to discover such physics and develop novel optoelectronic applications. Although vdW heterostructures have been grown by chemical vapor deposition, the available choices of materials for stacking is limited and the device yield is yet to be improved. Another approach to build vdW heterostructure relies on wet/dry transfer techniques like stacking Lego bricks. Although previous reviews have surveyed various wet transfer techniques, novel dry transfer techniques have been recently been demonstrated, featuring clean and sharp interfaces, which also gets rid of contamination, wrinkles, bubbles formed during wet transfer. This review summarizes the optimized dry transfer methods, which paves the way towards high-quality 2D material heterostructures with optimized interfaces. Such transfer techniques also lead to new physical phenomena while enable novel optoelectronic applications on artificial vdW heterostructures, which are discussed in the last part of this review.
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Affiliation(s)
- Huihan Li
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
- Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
| | - Xiaolu Xiong
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
- Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
| | - Fei Hui
- School of Materials Science and Engineering, The Key Laboratory of Material Processing and Mold of Ministry of Education, Henan Key Laboratory of Advanced Nylon Materials and Application, Zhengzhou University, Zhengzhou, 450001, People's Republic of China
| | - Dongliang Yang
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
- Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
| | - Jinbao Jiang
- School of Microelectronic Science and Technology, Sun Yat-Sen University, Zhuhai, 519082, People's Republic of China
| | - Wanxiang Feng
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
- Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
| | - Junfeng Han
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
- Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
| | - Junxi Duan
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
- Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
| | - Zhongrui Wang
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
| | - Linfeng Sun
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
- Beijing Key Lab of Nanophotonics & Ultrafine Optoelectronic Systems, School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
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34
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Maruvada A, Shubhakar K, Raghavan N, Pey KL, O'Shea SJ. Dielectric breakdown of 2D muscovite mica. Sci Rep 2022; 12:14076. [PMID: 35982110 PMCID: PMC9388672 DOI: 10.1038/s41598-022-18320-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/09/2022] [Indexed: 11/09/2022] Open
Abstract
Localized electrical breakdown (BD) measurements are performed on 2D muscovite mica flakes of ~ 2 to 15 nm thickness using Conduction Atomic Force Microscopy (CAFM). To obtain robust BD data by CAFM, the probed locations are spaced sufficiently far apart (> 1 µm) to avoid mutual interference and the maximum current is set to a low value (< 1 nA) to ensure severe damage does not occur to the sample. The analyses reveals that 2D muscovite mica has high electrical breakdown strength (12 MV/cm or more) and low leakage current, comparable to 2D hexagonal boron nitride (h-BN) of similar thickness. However, a significant difference compared to h-BN is the very low current necessary to avoid catastrophic damage during the BD event, even for very thin (2-3 nm) flakes. Further, for mica the BD transient always appear to be very abrupt, and no progressive BD process was definitively observed. These marked differences between mica and h-BN are attributed to the poor thermal conductivity of mica.
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Affiliation(s)
- Anirudh Maruvada
- Engineering Product Development, Singapore University of Technology and Design, 8 Somapah Road, Singapore, 487372, Singapore
| | - Kalya Shubhakar
- Engineering Product Development, Singapore University of Technology and Design, 8 Somapah Road, Singapore, 487372, Singapore
| | - Nagarajan Raghavan
- Engineering Product Development, Singapore University of Technology and Design, 8 Somapah Road, Singapore, 487372, Singapore
| | - Kin Leong Pey
- Engineering Product Development, Singapore University of Technology and Design, 8 Somapah Road, Singapore, 487372, Singapore
| | - Sean J O'Shea
- Institute of Materials Research and Engineering, Agency for Science Technology and Research, 2 Fusionopolis Way, Singapore, 138634, Singapore.
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35
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Ping X, Liu W, Wu Y, Xu G, Chen F, Li G, Jiao L. Electrochemical Construction of Edge-Contacted Metal-Semiconductor Junctions with Low Contact Barrier. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2202484. [PMID: 35642101 DOI: 10.1002/adma.202202484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 05/04/2022] [Indexed: 06/15/2023]
Abstract
2D semiconductors, such as MoS2 have emerged as promising ultrathin channel materials for the further scaling of field-effect transistors (FETs). However, the contact barrier at the metal-2D semiconductor junctions still significantly limits the device's performance. By extending the application of electrochemical deposition in 2D electronics, a distinct approach is developed for constructing metal-2D semiconductor junctions in an edge-contacted configuration through the edge-guided electrodeposition of varied metals. Both high-resolution microscopic imaging and electrical transport measurements confirm the successful creation of high-quality Pd-2D MoS2 junctions in desired geometry by combining electrodeposition with lithographic patterning. FETs are fabricated on the obtained Pd-2D MoS2 junctions and it is confirmed that these junctions exhibit a reduced contact barrier of ≈20 meV and extremely low contact resistance of 290 Ω µm and thus increase the averaged mobility of MoS2 FETs to ≈108 cm2 V -1 s-1 . This approach paves a new way for the construction of metal-semiconductor junctions and also demonstrates the great potential of the electrochemical deposition technique in 2D electronics.
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Affiliation(s)
- Xiaofan Ping
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Weigang Liu
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yueyang Wu
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Guanchen Xu
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Fengen Chen
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Guangtao Li
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Liying Jiao
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
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36
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Umakoshi T, Kawashima K, Moriyama T, Kato R, Verma P. Tip-enhanced Raman spectroscopy with amplitude-controlled tapping-mode AFM. Sci Rep 2022; 12:12776. [PMID: 35896604 PMCID: PMC9329313 DOI: 10.1038/s41598-022-17170-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 07/21/2022] [Indexed: 11/24/2022] Open
Abstract
Tip-enhanced Raman spectroscopy (TERS) is a powerful tool for analyzing chemical compositions at the nanoscale owing to near-field light localized at a metallic tip. In TERS, atomic force microscopy (AFM) is commonly used for tip position control. AFM is often controlled under the contact mode for TERS, whereas the tapping mode, which is another major operation mode, has not often been employed despite several advantages, such as low sample damage. One of the reasons is the low TERS signal intensity because the tip is mostly away from the sample during the tapping motion. In this study, we quantitatively investigated the effect of the tapping amplitude on the TERS signal. We numerically evaluated the dependence of the TERS signal on tapping amplitude. We found that the tapping amplitude had a significant effect on the TERS signal, and an acceptable level of TERS signal was obtained by reducing the amplitude to a few nanometers. We further demonstrated amplitude-controlled tapping-mode TERS measurement. We observed a strong dependence of the TERS intensity on the tapping amplitude, which is in agreement with our numerical calculations. This practical but essential study encourages the use of the tapping mode for further advancing TERS and related optical techniques.
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Affiliation(s)
- Takayuki Umakoshi
- Department of Applied Physics, Osaka University, Suita, Osaka, 565-0871, Japan. .,Institute for Advanced Co-creation Studies, Osaka University, Suita, Osaka, 565-0871, Japan. .,PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan.
| | - Koji Kawashima
- Department of Applied Physics, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Toki Moriyama
- Department of Applied Physics, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Ryo Kato
- Institute of Post-LED Photonics, Tokushima University, Tokushima, Tokushima, 770-8506, Japan
| | - Prabhat Verma
- Department of Applied Physics, Osaka University, Suita, Osaka, 565-0871, Japan
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37
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Reidy K, Thomsen JD, Lee HY, Zarubin V, Yu Y, Wang B, Pham T, Periwal P, Ross FM. Mechanisms of Quasi van der Waals Epitaxy of Three-Dimensional Metallic Nanoislands on Suspended Two-Dimensional Materials. NANO LETTERS 2022; 22:5849-5858. [PMID: 35852159 DOI: 10.1021/acs.nanolett.2c01682] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Understanding structure at the interface between two-dimensional (2D) materials and 3D metals is crucial for designing novel 2D/3D heterostructures and improving the performance of many 2D material devices. Here, we quantify and discuss the 2D/3D interface structure and the 3D morphology in several materials systems. We first deposit faceted Au nanoislands on graphene and transition metal dichalcogenides, using measurements of the equilibrium island shape to determine values for the 2D/Au interface energy and examining the role of surface reconstructions, chemical identity, and defects on the grown structures. We then deposit the technologically relevant metals Ti and Nb under conditions where kinetic rather than thermodynamic factors govern growth. We describe a transition from dendritic to faceted islands as a function of growth temperature and discuss the factors determining island shape in these materials systems. Finally, we show that suspended 2D materials enable the fabrication of a novel type of 3D/2D/3D heterostructure and discuss the growth mechanism. We suggest that emerging nanodevices will utilize versatile fabrication of 2D/3D heterostructures with well-characterized interfaces and morphologies.
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Affiliation(s)
- Kate Reidy
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Joachim Dahl Thomsen
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Hae Yeon Lee
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Vera Zarubin
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Yang Yu
- Raith America Inc., International Applications Center, 300 Jordan Road, Troy, New York 12180, United States
| | - Baoming Wang
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Thang Pham
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Priyanka Periwal
- IBM T. J. Watson Research Center, Yorktown Heights, New York 10598, United States
| | - Frances M Ross
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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38
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Kim HU, Seok H, Kang WS, Kim T. The first progress of plasma-based transition metal dichalcogenide synthesis: a stable 1T phase and promising applications. NANOSCALE ADVANCES 2022; 4:2962-2972. [PMID: 36133517 PMCID: PMC9417878 DOI: 10.1039/d1na00882j] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 04/24/2022] [Indexed: 06/16/2023]
Abstract
Two-dimensional (2D) transition metal dichalcogenides (TMDs) have attracted attention as polymorphs depending on their phases (1T and 2H) when applying typical synthesis methods. The 2H phase is generally synthesised through chemical vapour deposition (CVD) on a wafer-scale at high temperatures, and many synthesis methods have been reported owing to their thermodynamic stability and semiconductor properties. By contrast, although the 1T phase is meta-stable with an octahedral coordination, thereby limiting the use of synthesis methods, the recent structural advantage in terms of the hydrogen evolution reaction (HER) has been emphasised. Despite this demand, no large-area thin-film synthesis method for 1T-TMDs has been developed. Among several strategies of synthesizing metallic-phase (1T) TMDs, chemical exfoliation (alkali metal intercalation) is a major strategy and others have been used for electron-beam irradiation, laser irradiation, defects, plasma hot electron transfer, and mechanical strain. Therefore, we suggest an innovative synthesis method using plasma-enhanced CVD (PECVD) for both the 1T and 2H phases of TMDs (MoS2 and WS2). Because ions and radicals are accelerated to the substrate within the sheath region, a high-temperature source is not needed for vapour ionisation, and thus the process temperature can be significantly lowered (150 °C). Moreover, a 4-inch wafer-scale of a thin film is an advantage and can be synthesised on arbitrary substrates (SiO2/Si wafer, glassy carbon electrode, Teflon, and polyimide). Furthermore, the PECVD method was applied to TMD-graphene heterostructure films with a graphene-transferred substrate, and for the first time, sequential metal seed layer depositions of W (1 nm) and Mo (1 nm) were sulfurized to MoS2-WS2 vertical heterostructures with Ar + H2S plasma. We considered the prospects and challenges of the new PECVD method in the development of practical applications in next-generation integrated electronics, HER catalysts, and flexible biosensors.
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Affiliation(s)
- Hyeong-U Kim
- Department of Plasma Engineering, Korea Institute of Machinery & Materials (KIMM) Daejeon 34103 Korea
| | - Hyunho Seok
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University Suwon 16419 Korea
| | - Woo Seok Kang
- Department of Plasma Engineering, Korea Institute of Machinery & Materials (KIMM) Daejeon 34103 Korea
| | - Taesung Kim
- SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University Suwon 16419 Korea
- School of Mechanical Engineering, Sungkyunkwan University Suwon 16419 Korea
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39
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MoS2 as a Co-Catalyst for Photocatalytic Hydrogen Production: A Mini Review. Molecules 2022; 27:molecules27103289. [PMID: 35630769 PMCID: PMC9145188 DOI: 10.3390/molecules27103289] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/09/2022] [Accepted: 05/17/2022] [Indexed: 02/04/2023] Open
Abstract
Molybdenum disulfide (MoS2), with a two-dimensional (2D) structure, has attracted huge research interest due to its unique electrical, optical, and physicochemical properties. MoS2 has been used as a co-catalyst for the synthesis of novel heterojunction composites with enhanced photocatalytic hydrogen production under solar light irradiation. In this review, we briefly highlight the atomic-scale structure of MoS2 nanosheets. The top-down and bottom-up synthetic methods of MoS2 nanosheets are described. Additionally, we discuss the formation of MoS2 heterostructures with titanium dioxide (TiO2), graphitic carbon nitride (g-C3N4), and other semiconductors and co-catalysts for enhanced photocatalytic hydrogen generation. This review addresses the challenges and future perspectives for enhancing solar hydrogen production performance in heterojunction materials using MoS2 as a co-catalyst.
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40
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Sun Z, Han X, Cai Z, Yue S, Geng D, Rong D, Zhao L, Zhang YQ, Cheng P, Chen L, Zhou X, Huang Y, Wu K, Feng B. Exfoliation of 2D van der Waals crystals in ultrahigh vacuum for interface engineering. Sci Bull (Beijing) 2022; 67:1345-1351. [DOI: 10.1016/j.scib.2022.05.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 04/26/2022] [Accepted: 05/24/2022] [Indexed: 12/01/2022]
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41
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Huang Z, Cuniberto E, Park S, Kisslinger K, Wu Q, Taniguchi T, Watanabe K, Yager KG, Shahrjerdi D. Mechanisms of Interface Cleaning in Heterostructures Made from Polymer-Contaminated Graphene. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2201248. [PMID: 35388971 DOI: 10.1002/smll.202201248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Indexed: 06/14/2023]
Abstract
Heterostructures obtained from layered assembly of 2D materials such as graphene and hexagonal boron nitride have potential in the development of new electronic devices. Whereas various materials techniques can now produce macroscopic scale graphene, the construction of similar size heterostructures with atomically clean interfaces is still unrealized. A primary barrier has been the inability to remove polymeric residues from the interfaces that arise between layers when fabricating heterostructures. Here, the interface cleaning problem of polymer-contaminated heterostructures is experimentally studied from an energy viewpoint. With this approach, it is established that the interface cleaning mechanism involves a combination of thermally activated polymer residue mobilization and their mechanical actuation. This framework allows a systematic approach for fabricating record large-area clean heterostructures from polymer-contaminated graphene. These heterostructures provide state-of-the-art electronic performance. This study opens new strategies for the scalable production of layered materials heterostructures.
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Affiliation(s)
- Zhujun Huang
- Electrical and Computer Engineering, New York University, Brooklyn, NY, 11201, USA
| | - Edoardo Cuniberto
- Electrical and Computer Engineering, New York University, Brooklyn, NY, 11201, USA
| | - Suji Park
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Kim Kisslinger
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Qin Wu
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute of Materials Science, 1-1 Namiki Tsukuba, Ibaraki, 305-0044, Japan
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute of Materials Science, 1-1 Namiki Tsukuba, Ibaraki, 305-0044, Japan
| | - Kevin G Yager
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - Davood Shahrjerdi
- Electrical and Computer Engineering, New York University, Brooklyn, NY, 11201, USA
- Center for Quantum Phenomena, Physics Department, New York University, New York, NY, 10003, USA
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42
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Dai C, Liu Y, Wei D. Two-Dimensional Field-Effect Transistor Sensors: The Road toward Commercialization. Chem Rev 2022; 122:10319-10392. [PMID: 35412802 DOI: 10.1021/acs.chemrev.1c00924] [Citation(s) in RCA: 57] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The evolutionary success in information technology has been sustained by the rapid growth of sensor technology. Recently, advances in sensor technology have promoted the ambitious requirement to build intelligent systems that can be controlled by external stimuli along with independent operation, adaptivity, and low energy expenditure. Among various sensing techniques, field-effect transistors (FETs) with channels made of two-dimensional (2D) materials attract increasing attention for advantages such as label-free detection, fast response, easy operation, and capability of integration. With atomic thickness, 2D materials restrict the carrier flow within the material surface and expose it directly to the external environment, leading to efficient signal acquisition and conversion. This review summarizes the latest advances of 2D-materials-based FET (2D FET) sensors in a comprehensive manner that contains the material, operating principles, fabrication technologies, proof-of-concept applications, and prototypes. First, a brief description of the background and fundamentals is provided. The subsequent contents summarize physical, chemical, and biological 2D FET sensors and their applications. Then, we highlight the challenges of their commercialization and discuss corresponding solution techniques. The following section presents a systematic survey of recent progress in developing commercial prototypes. Lastly, we summarize the long-standing efforts and prospective future development of 2D FET-based sensing systems toward commercialization.
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Affiliation(s)
- Changhao Dai
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China.,Laboratory of Molecular Materials and Devices, Fudan University, Shanghai 200433, China
| | - Yunqi Liu
- Laboratory of Molecular Materials and Devices, Fudan University, Shanghai 200433, China
| | - Dacheng Wei
- State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai 200433, China.,Laboratory of Molecular Materials and Devices, Fudan University, Shanghai 200433, China
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43
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Lei Z, Zhang X, Zhao Y, Wei A, Tao L, Yang Y, Zheng Z, Tao L, Yu P, Li J. Enhanced Raman scattering on two-dimensional palladium diselenide. NANOSCALE 2022; 14:4181-4187. [PMID: 35234226 DOI: 10.1039/d1nr07126b] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Two-dimensional (2D) semiconductors with atomic layers, and a flat and active surface provide an attractive platform for the study of surface-enhanced Raman scattering (SERS). Many 2D layered materials, including graphene and transition metal dichalcogenide (TMD), have been exploited as potential Raman enhancers for SERS-based molecule sensing. Herein, atomically-thin palladium diselenide (PdSe2) used as a SERS substrate for molecule detection was systematically studied. Stable Raman enhancement for molecules such as rhodamine 6G (R6G), crystal violet (CV), and rhodamine B (RhB) on few-layer PdSe2 has been verified. A detection limit as low as 10-9 M and an enhancement factor of 105 for the R6G molecule on monolayer PdSe2 are achieved. With the insertion of a thin Al2O3 layer, the Raman spectra confirm the predominant charge transfer mechanism for the large Raman enhancement. Furthermore, the strong thickness-dependent properties, good in-plane anisotropy and excellent air-stability of Raman enhancement are also explored for 2D PdSe2. Our findings provide not only a promising Raman enhancement platform for sensing applications but also new insights into the chemical mechanism (CM) process of SERS.
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Affiliation(s)
- Zehong Lei
- Guangdong Provincial Key Laboratory of Information Photonics Technology, Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, School of Material and Energy, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Xinkuo Zhang
- Guangdong Provincial Key Laboratory of Information Photonics Technology, Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, School of Material and Energy, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Yu Zhao
- Guangdong Provincial Key Laboratory of Information Photonics Technology, Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, School of Material and Energy, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Aixiang Wei
- Guangdong Provincial Key Laboratory of Information Photonics Technology, Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, School of Material and Energy, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Lili Tao
- Guangdong Provincial Key Laboratory of Information Photonics Technology, Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, School of Material and Energy, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Yibin Yang
- Guangdong Provincial Key Laboratory of Information Photonics Technology, Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, School of Material and Energy, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Zhaoqiang Zheng
- Guangdong Provincial Key Laboratory of Information Photonics Technology, Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, School of Material and Energy, Guangdong University of Technology, Guangzhou 510006, People's Republic of China.
| | - Li Tao
- Key Lab of Advanced Optoelectronic Quantum Architecture and Measurement (Ministry of Education), School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Peng Yu
- State Key Laboratory of Optoelectronic Materials and Technologies, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, P.R. China
| | - Jingbo Li
- Guangdong Key Lab of Chip and Integration Technology, Institute of Semiconductors, South China Normal University, Guangzhou 510631, P.R. China
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Jia L, Wu J, Zhang Y, Qu Y, Jia B, Chen Z, Moss DJ. Fabrication Technologies for the On-Chip Integration of 2D Materials. SMALL METHODS 2022; 6:e2101435. [PMID: 34994111 DOI: 10.1002/smtd.202101435] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/12/2021] [Indexed: 06/14/2023]
Abstract
With compact footprint, low energy consumption, high scalability, and mass producibility, chip-scale integrated devices are an indispensable part of modern technological change and development. Recent advances in 2D layered materials with their unique structures and distinctive properties have motivated their on-chip integration, yielding a variety of functional devices with superior performance and new features. To realize integrated devices incorporating 2D materials, it requires a diverse range of device fabrication techniques, which are of fundamental importance to achieve good performance and high reproducibility. This paper reviews the state-of-art fabrication techniques for the on-chip integration of 2D materials. First, an overview of the material properties and on-chip applications of 2D materials is provided. Second, different approaches used for integrating 2D materials on chips are comprehensively reviewed, which are categorized into material synthesis, on-chip transfer, film patterning, and property tuning/modification. Third, the methods for integrating 2D van der Waals heterostructures are also discussed and summarized. Finally, the current challenges and future perspectives are highlighted.
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Affiliation(s)
- Linnan Jia
- Optical Sciences Centre, Swinburne University of Technology, Hawthorn, VIC, 3122, Australia
| | - Jiayang Wu
- Optical Sciences Centre, Swinburne University of Technology, Hawthorn, VIC, 3122, Australia
| | - Yuning Zhang
- Optical Sciences Centre, Swinburne University of Technology, Hawthorn, VIC, 3122, Australia
| | - Yang Qu
- Optical Sciences Centre, Swinburne University of Technology, Hawthorn, VIC, 3122, Australia
| | - Baohua Jia
- Centre for Translational Atomaterials, Swinburne University of Technology, Hawthorn, VIC, 3122, Australia
| | - Zhigang Chen
- MOE Key Laboratory of Weak-Light Nonlinear Photonics, TEDA Applied Physics Institute and School of Physics, Nankai University, Tianjin, 300457, China
- Department of Physics and Astronomy, San Francisco State University, San Francisco, CA, 94132, USA
| | - David J Moss
- Optical Sciences Centre, Swinburne University of Technology, Hawthorn, VIC, 3122, Australia
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45
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Di Bernardo I, Blyth J, Watson L, Xing K, Chen YH, Chen SY, Edmonds MT, Fuhrer MS. Defects, band bending and ionization rings in MoS 2. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:174002. [PMID: 35081526 DOI: 10.1088/1361-648x/ac4f1d] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 01/26/2022] [Indexed: 06/14/2023]
Abstract
Chalcogen vacancies in transition metal dichalcogenides are widely acknowledged as both donor dopants and as a source of disorder. The electronic structure of sulphur vacancies in MoS2however is still controversial, with discrepancies in the literature pertaining to the origin of the in-gap features observed via scanning tunneling spectroscopy (STS) on single sulphur vacancies. Here we use a combination of scanning tunnelling microscopy and STS to study embedded sulphur vacancies in bulk MoS2crystals. We observe spectroscopic features dispersing in real space and in energy, which we interpret as tip position- and bias-dependent ionization of the sulphur vacancy donor due to tip induced band bending. The observations indicate that care must be taken in interpreting defect spectra as reflecting in-gap density of states, and may explain discrepancies in the literature.
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Affiliation(s)
- Iolanda Di Bernardo
- Australian Research Council Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Clayton, 3800, VIC, Australia
- School of Physics and Astronomy, Monash University, Clayton, 3800, VIC, Australia
| | - James Blyth
- Australian Research Council Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Clayton, 3800, VIC, Australia
- School of Physics and Astronomy, Monash University, Clayton, 3800, VIC, Australia
| | - Liam Watson
- Australian Research Council Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Clayton, 3800, VIC, Australia
- School of Physics and Astronomy, Monash University, Clayton, 3800, VIC, Australia
| | - Kaijian Xing
- School of Physics and Astronomy, Monash University, Clayton, 3800, VIC, Australia
| | - Yi-Hsun Chen
- Australian Research Council Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Clayton, 3800, VIC, Australia
- School of Physics and Astronomy, Monash University, Clayton, 3800, VIC, Australia
| | - Shao-Yu Chen
- Australian Research Council Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Clayton, 3800, VIC, Australia
- School of Physics and Astronomy, Monash University, Clayton, 3800, VIC, Australia
| | - Mark T Edmonds
- Australian Research Council Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Clayton, 3800, VIC, Australia
- School of Physics and Astronomy, Monash University, Clayton, 3800, VIC, Australia
- Monash Centre for Atomically Thin Materials, Monash University, Clayton, 3800, VIC, Australia
| | - Michael S Fuhrer
- Australian Research Council Centre of Excellence in Future Low-Energy Electronics Technologies, Monash University, Clayton, 3800, VIC, Australia
- School of Physics and Astronomy, Monash University, Clayton, 3800, VIC, Australia
- Monash Centre for Atomically Thin Materials, Monash University, Clayton, 3800, VIC, Australia
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46
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Atomically Thin 2D van der Waals Magnetic Materials: Fabrications, Structure, Magnetic Properties and Applications. COATINGS 2022. [DOI: 10.3390/coatings12020122] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Two-dimensional (2D) van der Waals (vdW) magnetic materials are considered to be ideal candidates for the fabrication of spintronic devices because of their low dimensionality, allowing the quantization of electronic states and more degrees of freedom for device modulation. With the discovery of few-layer Cr2Ge2Te6 and monolayer CrI3 ferromagnets, the magnetism of 2D vdW materials is becoming a research focus in the fields of material science and physics. In theory, taking the Heisenberg model with finite-range exchange interactions as an example, low dimensionality and ferromagnetism are in competition. In other words, it is difficult for 2D materials to maintain their magnetism. However, the introduction of anisotropy in 2D magnetic materials enables the realization of long-range ferromagnetic order in atomically layered materials, which may offer new effective means for the design of 2D ferromagnets with high Curie temperature. Herein, current advances in the field of 2D vdW magnetic crystals, as well as intrinsic and induced ferromagnetism or antiferromagnetism, physical properties, device fabrication, and potential applications, are briefly summarized and discussed.
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47
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Zhou R, Wu J, Chen Y, Xie L. Polymorph Structures, Rich Physical Properties and Potential Applications of
Two‐Dimensional MoTe
2
,
WTe
2
and Its Alloys. CHINESE J CHEM 2022. [DOI: 10.1002/cjoc.202100777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Rui Zhou
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, National Center for Nanoscience and Technology Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Juanxia Wu
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, National Center for Nanoscience and Technology Beijing 100190 China
| | - Yuansha Chen
- Beijing National Laboratory for Condensed Matter Physics & Institute of Physics, Chinese Academy of Sciences Beijing 100190 China
| | - Liming Xie
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, National Center for Nanoscience and Technology Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
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48
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Panasci SE, Koos A, Schilirò E, Di Franco S, Greco G, Fiorenza P, Roccaforte F, Agnello S, Cannas M, Gelardi FM, Sulyok A, Nemeth M, Pécz B, Giannazzo F. Multiscale Investigation of the Structural, Electrical and Photoluminescence Properties of MoS 2 Obtained by MoO 3 Sulfurization. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:182. [PMID: 35055201 PMCID: PMC8778062 DOI: 10.3390/nano12020182] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 01/01/2022] [Accepted: 01/03/2022] [Indexed: 01/27/2023]
Abstract
In this paper, we report a multiscale investigation of the compositional, morphological, structural, electrical, and optical emission properties of 2H-MoS2 obtained by sulfurization at 800 °C of very thin MoO3 films (with thickness ranging from ~2.8 nm to ~4.2 nm) on a SiO2/Si substrate. XPS analyses confirmed that the sulfurization was very effective in the reduction of the oxide to MoS2, with only a small percentage of residual MoO3 present in the final film. High-resolution TEM/STEM analyses revealed the formation of few (i.e., 2-3 layers) of MoS2 nearly aligned with the SiO2 surface in the case of the thinnest (~2.8 nm) MoO3 film, whereas multilayers of MoS2 partially standing up with respect to the substrate were observed for the ~4.2 nm one. Such different configurations indicate the prevalence of different mechanisms (i.e., vapour-solid surface reaction or S diffusion within the film) as a function of the thickness. The uniform thickness distribution of the few-layer and multilayer MoS2 was confirmed by Raman mapping. Furthermore, the correlative plot of the characteristic A1g-E2g Raman modes revealed a compressive strain (ε ≈ -0.78 ± 0.18%) and the coexistence of n- and p-type doped areas in the few-layer MoS2 on SiO2, where the p-type doping is probably due to the presence of residual MoO3. Nanoscale resolution current mapping by C-AFM showed local inhomogeneities in the conductivity of the few-layer MoS2, which are well correlated to the lateral changes in the strain detected by Raman. Finally, characteristic spectroscopic signatures of the defects/disorder in MoS2 films produced by sulfurization were identified by a comparative analysis of Raman and photoluminescence (PL) spectra with CVD grown MoS2 flakes.
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Affiliation(s)
- Salvatore E. Panasci
- Consiglio Nazionale delle Ricerche—Istituto per la Microelettronica e Microsistemi (CNR-IMM), Strada VIII 5, 95121 Catania, Italy; (S.E.P.); (E.S.); (S.D.F.); (G.G.); (P.F.); (F.R.); (S.A.)
- Department of Physics and Astronomy, University of Catania, 95123 Catania, Italy
| | - Antal Koos
- Centre for Energy Research, Institute of Technical Physics and Materials Science, Konkoly-Thege ut 29-33, 1121 Budapest, Hungary; (A.K.); (A.S.); (M.N.)
| | - Emanuela Schilirò
- Consiglio Nazionale delle Ricerche—Istituto per la Microelettronica e Microsistemi (CNR-IMM), Strada VIII 5, 95121 Catania, Italy; (S.E.P.); (E.S.); (S.D.F.); (G.G.); (P.F.); (F.R.); (S.A.)
| | - Salvatore Di Franco
- Consiglio Nazionale delle Ricerche—Istituto per la Microelettronica e Microsistemi (CNR-IMM), Strada VIII 5, 95121 Catania, Italy; (S.E.P.); (E.S.); (S.D.F.); (G.G.); (P.F.); (F.R.); (S.A.)
| | - Giuseppe Greco
- Consiglio Nazionale delle Ricerche—Istituto per la Microelettronica e Microsistemi (CNR-IMM), Strada VIII 5, 95121 Catania, Italy; (S.E.P.); (E.S.); (S.D.F.); (G.G.); (P.F.); (F.R.); (S.A.)
| | - Patrick Fiorenza
- Consiglio Nazionale delle Ricerche—Istituto per la Microelettronica e Microsistemi (CNR-IMM), Strada VIII 5, 95121 Catania, Italy; (S.E.P.); (E.S.); (S.D.F.); (G.G.); (P.F.); (F.R.); (S.A.)
| | - Fabrizio Roccaforte
- Consiglio Nazionale delle Ricerche—Istituto per la Microelettronica e Microsistemi (CNR-IMM), Strada VIII 5, 95121 Catania, Italy; (S.E.P.); (E.S.); (S.D.F.); (G.G.); (P.F.); (F.R.); (S.A.)
| | - Simonpietro Agnello
- Consiglio Nazionale delle Ricerche—Istituto per la Microelettronica e Microsistemi (CNR-IMM), Strada VIII 5, 95121 Catania, Italy; (S.E.P.); (E.S.); (S.D.F.); (G.G.); (P.F.); (F.R.); (S.A.)
- Department of Physics and Chemistry Emilio Segrè, University of Palermo, 90123 Palermo, Italy; (M.C.); (F.M.G.)
- ATEN Center, University of Palermo, 90123 Palermo, Italy
| | - Marco Cannas
- Department of Physics and Chemistry Emilio Segrè, University of Palermo, 90123 Palermo, Italy; (M.C.); (F.M.G.)
| | - Franco M. Gelardi
- Department of Physics and Chemistry Emilio Segrè, University of Palermo, 90123 Palermo, Italy; (M.C.); (F.M.G.)
| | - Attila Sulyok
- Centre for Energy Research, Institute of Technical Physics and Materials Science, Konkoly-Thege ut 29-33, 1121 Budapest, Hungary; (A.K.); (A.S.); (M.N.)
| | - Miklos Nemeth
- Centre for Energy Research, Institute of Technical Physics and Materials Science, Konkoly-Thege ut 29-33, 1121 Budapest, Hungary; (A.K.); (A.S.); (M.N.)
| | - Béla Pécz
- Centre for Energy Research, Institute of Technical Physics and Materials Science, Konkoly-Thege ut 29-33, 1121 Budapest, Hungary; (A.K.); (A.S.); (M.N.)
| | - Filippo Giannazzo
- Consiglio Nazionale delle Ricerche—Istituto per la Microelettronica e Microsistemi (CNR-IMM), Strada VIII 5, 95121 Catania, Italy; (S.E.P.); (E.S.); (S.D.F.); (G.G.); (P.F.); (F.R.); (S.A.)
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Thomas CJ, Fonseca JJ, Spataru CD, Robinson JT, Ohta T. Electronic Structure and Stacking Arrangement of Tungsten Disulfide at the Gold Contact. ACS NANO 2021; 15:18060-18070. [PMID: 34623816 DOI: 10.1021/acsnano.1c06676] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
There is an intensive effort to control the nature of attractive interactions between ultrathin semiconductors and metals and to understand its impact on the electronic properties at the junction. Here, we present a photoelectron spectroscopy study on the interface between WS2 films and gold, with a focus on the occupied electronic states near the Brillouin zone center (i.e., the Γ point). To delineate the spectra of WS2 supported on crystalline Au from the suspended WS2, we employ a microscopy approach and a tailored sample structure, in which the WS2/Au junction forms a semi-epitaxial relationship and is adjacent to suspended WS2 regions. The photoelectron spectra, as a function of WS2 thickness, display the expected splitting of the highest occupied states at the Γ point. In multilayer WS2, we discovered variations in the electronic states that spatially align with the crystalline grains of underlying Au. Corroborated by density functional theory calculations, we attribute the electronic structure variations to stacking variations within the WS2 films. We propose that strong interactions exerted by Au grains cause slippage of the interfacing WS2 layer with respect to the rest of the WS2 film. Our findings illustrate that the electronic properties of transition metal dichalcogenides, and more generally 2D layered materials, are physically altered by the interactions with the interfacing materials, in addition to the electron screening and defects that have been widely considered.
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Affiliation(s)
- Cherrelle J Thomas
- Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - Jose J Fonseca
- National Research Council Postdoctoral Fellow at the Naval Research Laboratory, Washington, District of Columbia 20375 United States
| | - Catalin D Spataru
- Sandia National Laboratories, Livermore, California 94551, United States
| | - Jeremy T Robinson
- U.S. Naval Research Laboratory, Washington, District of Columbia 20375 United States
| | - Taisuke Ohta
- Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
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50
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Substrate-Driven Atomic Layer Deposition of High-κ Dielectrics on 2D Materials. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app112211052] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Atomic layer deposition (ALD) of high-κ dielectrics on two-dimensional (2D) materials (including graphene and transition metal dichalcogenides) still represents a challenge due to the lack of out-of-plane bonds on the pristine surfaces of 2D materials, thus making the nucleation process highly disadvantaged. The typical methods to promote the nucleation (i.e., the predeposition of seed layers or the surface activation via chemical treatments) certainly improve the ALD growth but can affect, to some extent, the electronic properties of 2D materials and the interface with high-κ dielectrics. Hence, direct ALD on 2D materials without seed and functionalization layers remains highly desirable. In this context, a crucial role can be played by the interaction with the substrate supporting the 2D membrane. In particular, metallic substrates such as copper or gold have been found to enhance the ALD nucleation of Al2O3 and HfO2 both on monolayer (1 L) graphene and MoS2. Similarly, uniform ALD growth of Al2O3 on the surface of 1 L epitaxial graphene (EG) on SiC (0001) has been ascribed to the peculiar EG/SiC interface properties. This review provides a detailed discussion of the substrate-driven ALD growth of high-κ dielectrics on 2D materials, mainly on graphene and MoS2. The nucleation mechanism and the influence of the ALD parameters (namely the ALD temperature and cycle number) on the coverage as well as the structural and electrical properties of the deposited high-κ thin films are described. Finally, the open challenges for applications are discussed.
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