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Liang D, Jiang B, Liu Z, Chen Z, Gao Y, Yang S, He R, Wang L, Ran J, Wang J, Gao P, Li J, Liu Z, Sun J, Wei T. Quasi van der Waals Epitaxy of Single Crystalline GaN on Amorphous SiO 2/ Si(100) for Monolithic Optoelectronic Integration. Adv Sci (Weinh) 2024:e2305576. [PMID: 38520076 DOI: 10.1002/advs.202305576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 01/09/2024] [Indexed: 03/25/2024]
Abstract
The realization of high quality (0001) GaN on Si(100) is paramount importance for the monolithic integration of Si-based integrated circuits and GaN-enabled optoelectronic devices. Nevertheless, thorny issues including large thermal mismatch and distinct crystal symmetries typically bring about uncontrollable polycrystalline GaN formation with considerable surface roughness on standard Si(100). Here a breakthrough of high-quality single-crystalline GaN film on polycrystalline SiO2/Si(100) is presented by quasi van der Waals epitaxy and fabricate the monolithically integrated photonic chips. The in-plane orientation of epilayer is aligned throughout a slip and rotation of high density AlN nuclei due to weak interfacial forces, while the out-of-plane orientation of GaN can be guided by multi-step growth on transfer-free graphene. For the first time, the monolithic integration of light-emitting diode (LED) and photodetector (PD) devices are accomplished on CMOS-compatible SiO2/Si(100). Remarkably, the self-powered PD affords a rapid response below 250 µs under adjacent LED radiation, demonstrating the responsivity and detectivity of 2.01 × 105 A/W and 4.64 × 1013 Jones, respectively. This work breaks a bottleneck of synthesizing large area single-crystal GaN on Si(100), which is anticipated to motivate the disruptive developments in Si-integrated optoelectronic devices.
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Affiliation(s)
- Dongdong Liang
- Research and Development Center for Semiconductor Lighting Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Bei Jiang
- Center for Nanochemistry (CNC), Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
- Beijing Graphene Institute (BGI), Beijing, 100095, P. R. China
| | - Zhetong Liu
- Center for Nanochemistry (CNC), Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
- Beijing Graphene Institute (BGI), Beijing, 100095, P. R. China
- Electron Microscopy Laboratory, and International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, P. R. China
| | - Zhaolong Chen
- Center for Nanochemistry (CNC), Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
- Beijing Graphene Institute (BGI), Beijing, 100095, P. R. China
| | - Yaqi Gao
- Research and Development Center for Semiconductor Lighting Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Shenyuan Yang
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, P. R. China
| | - Rui He
- Research and Development Center for Semiconductor Lighting Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Lulu Wang
- Research and Development Center for Semiconductor Lighting Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Junxue Ran
- Research and Development Center for Semiconductor Lighting Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Junxi Wang
- Research and Development Center for Semiconductor Lighting Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Peng Gao
- Center for Nanochemistry (CNC), Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
- Beijing Graphene Institute (BGI), Beijing, 100095, P. R. China
- Electron Microscopy Laboratory, and International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, P. R. China
| | - Jinmin Li
- Research and Development Center for Semiconductor Lighting Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Zhongfan Liu
- Center for Nanochemistry (CNC), Beijing Science and Engineering Center for Nanocarbons, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China
- Beijing Graphene Institute (BGI), Beijing, 100095, P. R. China
- College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies, Soochow University, Suzhou, 215006, P. R. China
| | - Jingyu Sun
- Beijing Graphene Institute (BGI), Beijing, 100095, P. R. China
- College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), Jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies, Soochow University, Suzhou, 215006, P. R. China
| | - Tongbo Wei
- Research and Development Center for Semiconductor Lighting Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, P. R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
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Sun M, Blasco R, Nwodo J, de la Mata M, Molina SI, Ajay A, Monroy E, Valdueza-Felip S, Naranjo FB. Comparison of the Material Quality of Al xIn 1-xN (x-0-0.50) Films Deposited on Si(100) and Si(111) at Low Temperature by Reactive RF Sputtering. Materials (Basel) 2022; 15:7373. [PMID: 36295439 PMCID: PMC9612173 DOI: 10.3390/ma15207373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 10/09/2022] [Accepted: 10/17/2022] [Indexed: 06/16/2023]
Abstract
AlxIn1-xN ternary semiconductors have attracted much interest for application in photovoltaic devices. Here, we compare the material quality of AlxIn1-xN layers deposited on Si with different crystallographic orientations, (100) and (111), via radio-frequency (RF) sputtering. To modulate their Al content, the Al RF power was varied from 0 to 225 W, whereas the In RF power and deposition temperature were fixed at 30 W and 300 °C, respectively. X-ray diffraction measurements reveal a c-axis-oriented wurtzite structure with no phase separation regardless of the Al content (x = 0-0.50), which increases with the Al power supply. The surface morphology of the AlxIn1-xN layers improves with increasing Al content (the root-mean-square roughness decreases from ≈12 to 2.5 nm), and it is similar for samples grown on both Si substrates. The amorphous layer (~2.5 nm thick) found at the interface with the substrates explains the weak influence of their orientation on the properties of the AlxIn1-xN films. Simultaneously grown AlxIn1-xN-on-sapphire samples point to a residual n-type carrier concentration in the 1020-1021 cm-3 range. The optical band gap energy of these layers evolves from 1.75 to 2.56 eV with the increase in the Al. PL measurements of AlxIn1-xN show a blue shift in the peak emission when adding the Al, as expected. We also observe an increase in the FWHM of the main peak and a decrease in the integrated emission with the Al content in room-temperature PL measurements. In general, the material quality of the AlxIn1-xN films on Si is similar for both crystallographic orientations.
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Affiliation(s)
- Michael Sun
- Photonics Engineering Group, Electronics Department, University of Alcalá, Madrid-Barcelona Road km 33.6, 28871 Alcalá de Henares, Spain
| | - Rodrigo Blasco
- Photonics Engineering Group, Electronics Department, University of Alcalá, Madrid-Barcelona Road km 33.6, 28871 Alcalá de Henares, Spain
- Science, Computations and Technology Department, European University of Madrid, Tajo Street s/n, 28670 Villaviciosa de Odón, Spain
| | - Julian Nwodo
- Fort Hare Institute of Technology, University of Fort Hare, Alice 5700, South Africa
| | - María de la Mata
- Departamento Ciencia de los Materiales, I.M. y Q.I., IMEYMAT, Universidad de Cádiz, Campus Río San Pedro s/n, Puerto Real, 11510 Cádiz, Spain
| | - Sergio I. Molina
- Departamento Ciencia de los Materiales, I.M. y Q.I., IMEYMAT, Universidad de Cádiz, Campus Río San Pedro s/n, Puerto Real, 11510 Cádiz, Spain
| | - Akhil Ajay
- CEA-Grenoble, INAC/PHELIQS, 17 av. des Martyrs, 38054 Grenoble, France
| | - Eva Monroy
- CEA-Grenoble, INAC/PHELIQS, 17 av. des Martyrs, 38054 Grenoble, France
| | - Sirona Valdueza-Felip
- Photonics Engineering Group, Electronics Department, University of Alcalá, Madrid-Barcelona Road km 33.6, 28871 Alcalá de Henares, Spain
| | - Fernando B. Naranjo
- Photonics Engineering Group, Electronics Department, University of Alcalá, Madrid-Barcelona Road km 33.6, 28871 Alcalá de Henares, Spain
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Frederick E, Dwyer KJ, Wang GT, Misra S, Butera RE. The stability of Cl-, Br-, and I-passivated Si(100)-(2 × 1) in ambient environments for atomically-precise pattern preservation. J Phys Condens Matter 2021; 33:444001. [PMID: 34348242 DOI: 10.1088/1361-648x/ac1aa4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Abstract
Atomic precision advanced manufacturing (APAM) leverages the highly reactive nature of Si dangling bonds relative to H- or Cl-passivated Si to selectively adsorb precursor molecules into lithographically defined areas with sub-nanometer resolution. Due to the high reactivity of dangling bonds, this process is confined to ultra-high vacuum (UHV) environments, which currently limits its commercialization and broad-based appeal. In this work, we explore the use of halogen adatoms to preserve APAM-derived lithographic patterns outside of UHV to enable facile transfer into real-world commercial processes. Specifically, we examine the stability of H-, Cl-, Br-, and I-passivated Si(100) in inert N2and ambient environments. Characterization with scanning tunneling microscopy and x-ray photoelectron spectroscopy (XPS) confirmed that each of the fully passivated surfaces were resistant to oxidation in 1 atm of N2for up to 44 h. Varying levels of surface degradation and contamination were observed upon exposure to the laboratory ambient environment. Characterization byex situXPS after ambient exposures ranging from 15 min to 8 h indicated the Br- and I-passivated Si surfaces were highly resistant to degradation, while Cl-passivated Si showed signs of oxidation within minutes of ambient exposure. As a proof-of-principle demonstration of pattern preservation, a H-passivated Si sample patterned and passivated with independent Cl, Br, I, and bare Si regions was shown to maintain its integrity in all but the bare Si region post-exposure to an N2environment. The successful demonstration of the preservation of APAM patterns outside of UHV environments opens new possibilities for transporting atomically-precise devices outside of UHV for integrating with non-UHV processes, such as other chemistries and commercial semiconductor device processes.
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Affiliation(s)
- E Frederick
- Sandia National Laboratories, Albuquerque, NM 87185, United States of America
| | - K J Dwyer
- Department of Physics, University of Maryland, College Park, MD 20742, United States of America
| | - G T Wang
- Sandia National Laboratories, Albuquerque, NM 87185, United States of America
| | - S Misra
- Sandia National Laboratories, Albuquerque, NM 87185, United States of America
| | - R E Butera
- Laboratory for Physical Sciences, 8050 Greenmead Drive, College Park, MD 20740, United States of America
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Chang CY, Lin CY, Lin DS. How dissociated fragments of multiatomic molecules saturate all active surface sites-H 2O adsorption on the Si(100) surface. J Phys Condens Matter 2021; 33:404004. [PMID: 34265758 DOI: 10.1088/1361-648x/ac14f7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 07/15/2021] [Indexed: 06/13/2023]
Abstract
A fundamental question for the adsorption of any gas molecule on surfaces is its saturation coverage, whose value can provide a comprehensive examination for the adsorption mechanisms, dynamic and kinetic processes involved in the adsorption processes. This investigation utilizes scanning tunneling microscopy to visualize the H2O adsorption processes on the Si(100) surface with a sub-monolayers (<0.05 ML) of chemically-reactive dangling bonds remaining after exposure to (1) a hydrogen atomic beam, (2) H2O, and (3) Cl2gases at room temperature. In all three cases, each of the remaining isolated single dangling bonds (sDB) adsorb and is passivated by either of the two dissociation fragments, the H or OH radical, to form a surface Si-H and Si-OH species. A new adsorption mechanism, termed 'dissociative and asynchronous chemisorption', is proposed for the observation presented herein. Upon approaching a sDB site, the H2O molecule breaks apart into two fragments. One is chemisorbed to the sDB. The other attaches to the same or the neighboring passivated dimer to form a transition state of surface diffusion, which then diffuses on the mostly passivated surface and is eventually chemisorbed to another reactive site. In other words, the chemisorption reactions of the two fragments after dissociation occur at different and uncorrelated time and places. This adsorption mechanism suggests that a diffusion transition state can be an adsorption product in the first step of the dissociative adsorption processes.
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Affiliation(s)
- Chan-Yuen Chang
- Department of Physics, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan
| | - Cheng-Yu Lin
- Department of Physics, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan
| | - Deng-Sung Lin
- Department of Physics, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan
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5
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Aprojanz J, Rosenzweig P, Nguyen TTN, Karakachian H, Küster K, Starke U, Lukosius M, Lippert G, Sinterhauf A, Wenderoth M, Zakharov AA, Tegenkamp C. High-Mobility Epitaxial Graphene on Ge/ Si(100) Substrates. ACS Appl Mater Interfaces 2020; 12:43065-43072. [PMID: 32865383 DOI: 10.1021/acsami.0c10725] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Graphene was shown to reveal intriguing properties of its relativistic two-dimensional electron gas; however, its implementation to microelectronic applications is missing to date. In this work, we present a comprehensive study of epitaxial graphene on technologically relevant and in a standard CMOS process achievable Ge(100) epilayers grown on Si(100) substrates. Crystalline graphene monolayer structures were grown by means of chemical vapor deposition (CVD). Using angle-resolved photoemission spectroscopy and in situ surface transport measurements, we demonstrate their metallic character both in momentum and real space. Despite numerous crystalline imperfections, e.g., grain boundaries and strong corrugation, as compared to epitaxial graphene on SiC(0001), charge carrier mobilities of 1 × 104 cm2/Vs were obtained at room temperature, which is a result of the quasi-charge neutrality within the graphene monolayers on germanium and not dependent on the presence of an interface oxide. The interface roughness due to the facet structure of the Ge(100) epilayer, formed during the CVD growth of graphene, can be reduced via subsequent in situ annealing up to 850 °C coming along with an increase in the mobility by 30%. The formation of a Ge(100)-(2 × 1) structure demonstrates the weak interaction and effective delamination of graphene from the Ge/Si(100) substrate.
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Affiliation(s)
- J Aprojanz
- Institut für Physik, Technische Universität Chemnitz, Chemnitz 09126, Germany
| | - Ph Rosenzweig
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, Stuttgart 70569, Germany
| | - T T Nhung Nguyen
- Institut für Physik, Technische Universität Chemnitz, Chemnitz 09126, Germany
| | - H Karakachian
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, Stuttgart 70569, Germany
| | - K Küster
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, Stuttgart 70569, Germany
| | - U Starke
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, Stuttgart 70569, Germany
| | - M Lukosius
- Leibniz-Institut für innovative Mikroelektronik, Im Technologiepark 25, Frankfurt (Oder) 15236, Germany
| | - G Lippert
- Leibniz-Institut für innovative Mikroelektronik, Im Technologiepark 25, Frankfurt (Oder) 15236, Germany
| | - A Sinterhauf
- IV. Physikalisches Institut, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
| | - M Wenderoth
- IV. Physikalisches Institut, Georg-August-Universität Göttingen, 37077 Göttingen, Germany
| | - A A Zakharov
- MAX IV Laboratory and Lund University, Lund 22100, Sweden
| | - C Tegenkamp
- Institut für Physik, Technische Universität Chemnitz, Chemnitz 09126, Germany
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Güniat L, Martí-Sánchez S, Garcia O, Boscardin M, Vindice D, Tappy N, Friedl M, Kim W, Zamani M, Francaviglia L, Balgarkashi A, Leran JB, Arbiol J, Fontcuberta I Morral A. III-V Integration on Si(100): Vertical Nanospades. ACS Nano 2019; 13:5833-5840. [PMID: 31038924 DOI: 10.1021/acsnano.9b01546] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
III-V integration on Si(100) is a challenge: controlled vertical vapor liquid solid nanowire growth on this platform has not been reported so far. Here we demonstrate an atypical GaAs vertical nanostructure on Si(100), coined nanospade, obtained by a nonconventional droplet catalyst pinning. The Ga droplet is positioned at the tip of an ultrathin Si pillar with a radial oxide envelope. The pinning at the Si/oxide interface allows the engineering of the contact angle beyond the Young-Dupré equation and the growth of vertical nanospades. Nanospades exhibit a virtually defect-free bicrystalline nature. Our growth model explains how a pentagonal twinning event at the initial stages of growth provokes the formation of the nanospade. The optical properties of the nanospades are consistent with the high crystal purity, making these structures viable for use in integration of optoelectronics on the Si(100) platform.
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Affiliation(s)
- Lucas Güniat
- Laboratoire des Matériaux Semiconducteurs , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
| | - Sara Martí-Sánchez
- Catalan Institute of Nanoscience and Nanotechnology (ICN2) , CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona , Catalonia , Spain
| | - Oscar Garcia
- UPC - Universitat Politècnica de Catalunya , Calle Jordi Girona, 1-3 , 08034 Barcelona , Spain
| | - Mégane Boscardin
- Laboratoire des Matériaux Semiconducteurs , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
| | - David Vindice
- Laboratoire des Matériaux Semiconducteurs , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
| | - Nicolas Tappy
- Laboratoire des Matériaux Semiconducteurs , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
| | - Martin Friedl
- Laboratoire des Matériaux Semiconducteurs , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
| | - Wonjong Kim
- Laboratoire des Matériaux Semiconducteurs , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
| | - Mahdi Zamani
- Laboratoire des Matériaux Semiconducteurs , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
| | - Luca Francaviglia
- Laboratoire des Matériaux Semiconducteurs , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
| | - Akshay Balgarkashi
- Laboratoire des Matériaux Semiconducteurs , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
| | - Jean-Baptiste Leran
- Laboratoire des Matériaux Semiconducteurs , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
| | - Jordi Arbiol
- Catalan Institute of Nanoscience and Nanotechnology (ICN2) , CSIC and BIST, Campus UAB, Bellaterra, 08193 Barcelona , Catalonia , Spain
- ICREA , Pg. Lluís Companys 23 , 08010 Barcelona , Catalonia , Spain
| | - Anna Fontcuberta I Morral
- Laboratory of Semiconductor Materials, Institute of Materials , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
- Institute of Physics , École Polytechnique Fédérale de Lausanne , 1015 Lausanne , Switzerland
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Abstract
We describe the fabrication, operation principles, and simulation of a coherent single-atom quantum interference device (QID) structure on Si(100) controlled by the properties of single atoms. The energy and spatial distribution of the wave functions associated with the device are visualized by scanning tunneling spectroscopy and the amplitude and phase of the evanescent wave functions that couple into the quantum well states are directly measured, including the action of an electrostatic gate. Density functional theory simulations were employed to simulate the electronic structure of the device structure, which is in excellent agreement with the measurements. Simulations of device transmission demonstrate that our coherent single-atom QID can have ON-OFF ratios in excess of 10(3) with potentially minimal power dissipation.
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Affiliation(s)
- Borislav Naydenov
- †School of Chemistry, ‡School of Physics, and §Center for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College, Dublin 2, Ireland
| | - Ivan Rungger
- †School of Chemistry, ‡School of Physics, and §Center for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College, Dublin 2, Ireland
| | - Mauro Mantega
- †School of Chemistry, ‡School of Physics, and §Center for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College, Dublin 2, Ireland
| | - Stefano Sanvito
- †School of Chemistry, ‡School of Physics, and §Center for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College, Dublin 2, Ireland
| | - John J Boland
- †School of Chemistry, ‡School of Physics, and §Center for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College, Dublin 2, Ireland
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Gupta T, Hannon JB, Tersoff J, Tromp RM, Ott JA, Bruley J, Steingart DA. Strain-driven mound formation of substrate under epitaxial nanoparticles. Nano Lett 2015; 15:34-38. [PMID: 25506710 DOI: 10.1021/nl502516y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We observe the growth of crystalline SiC nanoparticles on Si(001) at 900 °C using in situ electron microscopy. Following nucleation and growth of the SiC, there is a massive migration of Si, forming a crystalline Si mound underneath each nanoparticle that lifts it 4-5 nm above the initial growth surface. The volume of the Si mounds is roughly five to seven times the volume of the SiC nanoparticles. We propose that relaxation of strain drives the mound formation. This new mechanism for relieving interfacial strain, which involves a dramatic restructuring of the substrate, is in striking contrast to the familiar scenario in which only the deposited material restructures to relieve strain.
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Affiliation(s)
- Tanya Gupta
- Department of Mechanical and Aerospace Engineering and the Andlinger Center for Energy and The Environment and ‡IBM Research Division, T. J. Watson Research Center , Yorktown Heights, New York 10598, United States
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Sweetman A, Jarvis S, Danza R, Moriarty P. Effect of the tip state during qPlus noncontact atomic force microscopy of Si(100) at 5 K: Probing the probe. Beilstein J Nanotechnol 2012; 3:25-32. [PMID: 22428093 PMCID: PMC3304327 DOI: 10.3762/bjnano.3.3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Accepted: 12/03/2011] [Indexed: 05/05/2023]
Abstract
BACKGROUND Noncontact atomic force microscopy (NC-AFM) now regularly produces atomic-resolution images on a wide range of surfaces, and has demonstrated the capability for atomic manipulation solely using chemical forces. Nonetheless, the role of the tip apex in both imaging and manipulation remains poorly understood and is an active area of research both experimentally and theoretically. Recent work employing specially functionalised tips has provided additional impetus to elucidating the role of the tip apex in the observed contrast. RESULTS We present an analysis of the influence of the tip apex during imaging of the Si(100) substrate in ultra-high vacuum (UHV) at 5 K using a qPlus sensor for noncontact atomic force microscopy (NC-AFM). Data demonstrating stable imaging with a range of tip apexes, each with a characteristic imaging signature, have been acquired. By imaging at close to zero applied bias we eliminate the influence of tunnel current on the force between tip and surface, and also the tunnel-current-induced excitation of silicon dimers, which is a key issue in scanning probe studies of Si(100). CONCLUSION A wide range of novel imaging mechanisms are demonstrated on the Si(100) surface, which can only be explained by variations in the precise structural configuration at the apex of the tip. Such images provide a valuable resource for theoreticians working on the development of realistic tip structures for NC-AFM simulations. Force spectroscopy measurements show that the tip termination critically affects both the short-range force and dissipated energy.
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Affiliation(s)
- Adam Sweetman
- School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, U.K
| | - Sam Jarvis
- School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, U.K
| | - Rosanna Danza
- School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, U.K
| | - Philip Moriarty
- School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, U.K
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