1
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Chen C, Chu Y, Zhang L, Lin H, Fang W, Zhang Z, Zha C, Wang K, Yang H, Yu X, Gott JA, Aagesen M, Cheng Z, Huo S, Liu H, Sanchez AM, Zhang Y. Initialization of Nanowire or Cluster Growth Critically Controlled by the Effective V/III Ratio at the Early Nucleation Stage. J Phys Chem Lett 2023; 14:4433-4439. [PMID: 37141511 DOI: 10.1021/acs.jpclett.3c00484] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
For self-catalyzed nanowires (NWs), reports on how the catalytic droplet initiates successful NW growth are still lacking, making it difficult to control the yield and often accompanying a high density of clusters. Here, we have performed a systematic study on this issue, which reveals that the effective V/III ratio at the initial growth stage is a critical factor that governs the NW growth yield. To initiate NW growth, the ratio should be high enough to allow the nucleation to extend to the entire contact area between the droplet and substrate, which can elevate the droplet off of the substrate, but it should not be too high in order to keep the droplet. This study also reveals that the cluster growth between NWs is also initiated from large droplets. This study provides a new angle from the growth condition to explain the cluster formation mechanism, which can guide high-yield NW growth.
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Affiliation(s)
- Chen Chen
- College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
| | - Yanmeng Chu
- School of Micro-Nano Electronics, Zhejiang University, Hangzhou, Zhejiang 311200, China
| | - Linjun Zhang
- School of Micro-Nano Electronics, Zhejiang University, Hangzhou, Zhejiang 311200, China
| | - Haojun Lin
- College of Photonic and Electronic Engineering, Fujian Normal University, Fuzhou 350117, Fujian, China
| | - Wenzhang Fang
- School of Micro-Nano Electronics, Zhejiang University, Hangzhou, Zhejiang 311200, China
| | - Zheyu Zhang
- School of Micro-Nano Electronics, Zhejiang University, Hangzhou, Zhejiang 311200, China
| | - Chaofei Zha
- School of Micro-Nano Electronics, Zhejiang University, Hangzhou, Zhejiang 311200, China
| | - Kejia Wang
- School of Micro-Nano Electronics, Zhejiang University, Hangzhou, Zhejiang 311200, China
| | - Hui Yang
- Institute for Materials Discovery, University College London, Roberts Building, Malet Place, London WC1E 7JE, United Kingdom
| | - Xuezhe Yu
- Department of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
| | - James A Gott
- Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Martin Aagesen
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Zhiyuan Cheng
- School of Micro-Nano Electronics, Zhejiang University, Hangzhou, Zhejiang 311200, China
| | - Suguo Huo
- London Centre for Nanotechnology, University College London, London WC1H 0AH, United Kingdom
| | - Huiyun Liu
- Department of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
| | - Ana M Sanchez
- Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Yunyan Zhang
- School of Micro-Nano Electronics, Zhejiang University, Hangzhou, Zhejiang 311200, China
- Department of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
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2
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Chen L, Adeyemo SO, Fonseka HA, Liu H, Kar S, Yang H, Velichko A, Mowbray DJ, Cheng Z, Sanchez AM, Joyce HJ, Zhang Y. Long-Term Stability and Optoelectronic Performance Enhancement of InAsP Nanowires with an Ultrathin InP Passivation Layer. NANO LETTERS 2022; 22:3433-3439. [PMID: 35420433 PMCID: PMC9097579 DOI: 10.1021/acs.nanolett.2c00805] [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: 03/01/2022] [Revised: 03/25/2022] [Indexed: 06/14/2023]
Abstract
The influence of nanowire (NW) surface states increases rapidly with the reduction of diameter and hence severely degrades the optoelectronic performance of narrow-diameter NWs. Surface passivation is therefore critical, but it is challenging to achieve long-term effective passivation without significantly affecting other qualities. Here, we demonstrate that an ultrathin InP passivation layer of 2-3 nm can effectively solve these challenges. For InAsP nanowires with small diameters of 30-40 nm, the ultrathin passivation layer reduces the surface recombination velocity by at least 70% and increases the charge carrier lifetime by a factor of 3. These improvements are maintained even after storing the samples in ambient atmosphere for over 3 years. This passivation also greatly improves the performance thermal tolerance of these thin NWs and extends their operating temperature from <150 K to room temperature. This study provides a new route toward high-performance room-temperature narrow-diameter NW devices with long-term stability.
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Affiliation(s)
- LuLu Chen
- School
of Micro-Nano Electronics, Zhejiang University, Hangzhou, Zhejiang 311200, China
| | - Stephanie O. Adeyemo
- Electrical
Engineering Division, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom
| | - H. Aruni Fonseka
- Department
of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Huiyun Liu
- Department
of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
| | - Srabani Kar
- Electrical
Engineering Division, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom
| | - Hui Yang
- Institute
for Materials Discovery, University College
London, Roberts Building, Malet Place, London, WC1E 7JE, United Kingdom
| | - Anton Velichko
- Department
of Physics and Astronomy and the Photon Science Institute, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - David J. Mowbray
- Department
of Physics and Astronomy and the Photon Science Institute, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - Zhiyuan Cheng
- School
of Micro-Nano Electronics, Zhejiang University, Hangzhou, Zhejiang 311200, China
| | - Ana M. Sanchez
- Department
of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Hannah J Joyce
- Electrical
Engineering Division, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom
| | - Yunyan Zhang
- School
of Micro-Nano Electronics, Zhejiang University, Hangzhou, Zhejiang 311200, China
- Department
of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
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3
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Zhang X, Yang H, Zhang Y, Liu H. Design of high-quality reflectors for vertical III-V nanowire lasers on Si. NANOTECHNOLOGY 2021; 33:035202. [PMID: 34638105 DOI: 10.1088/1361-6528/ac2f22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 10/12/2021] [Indexed: 06/13/2023]
Abstract
Nanowires (NWs) with a unique one-dimensional structure can monolithically integrate high-quality III-V semiconductors onto Si platform, which is highly promising to build lasers for Si photonics. However, the lasing from vertically-standing NWs on silicon is much more difficult to achieve compared with NWs broken off from substrates, causing significant challenges in the integration. Here, the challenge of achieving vertically-standing NW lasers is systematically analysed with III-V materials, e.g. GaAs(P) and InAs(P). The poor optical reflectivity at the NW/Si interface results severe optical field leakage to the substrate, and the commonly used SiO2or Si2N3dielectric mask at the interface can only improve it to ∼10%, which is the major obstacle for achieving low-threshold lasing. A NW super lattice distributed Bragg reflector is therefore proposed, which is able to greatly improve the reflectivity to >97%. This study provides a highly-feasible method to greatly improve the performance of vertically-standing NW lasers, which can boost the rapid development of Si photonics.
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Affiliation(s)
- Xin Zhang
- Department of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
- Faculty of Electrical Engineering and Computer Science, Ningbo University, Ningbo 315211, People's Republic of China
| | - Hui Yang
- Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ, United Kingdom
| | - Yunyan Zhang
- Department of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
- Department of Physics, Universität Paderborn, Warburger Straße 100, D-33098, Paderborn, Germany
| | - Huiyun Liu
- Department of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
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4
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Wilson DP, Dubrovskii VG, LaPierre RR. Improving the yield of GaAs nanowires on silicon by Ga pre-deposition. NANOTECHNOLOGY 2021; 32:265301. [PMID: 33730697 DOI: 10.1088/1361-6528/abef93] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
GaAs nanowire (NW) arrays were grown by molecular beam epitaxy using the self-assisted vapor-liquid-solid method with Ga droplets as seed particles. A Ga pre-deposition step is examined to control NW yield and diameter. The NW yield can be increased with suitable duration of a Ga pre-deposition step but is highly dependent on oxide hole diameter and surface conditions. The NW diameter was determined by vapor-solid growth on the NW sidewalls, rather than Ga pre-deposition. The maximum NW yield with a Ga pre-deposition step was very close to 100%, established at shorter Ga deposition durations and for larger holes. This trend was explained within a model where maximum yield is obtained when the Ga droplet volume approximately equals the hole volume.
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Affiliation(s)
- D P Wilson
- Department of Engineering Physics, McMaster University, Hamilton, ON L8S4L7, Canada
| | - V G Dubrovskii
- Faculty of Physics, St. Petersburg State University, Universitetskaya Embankment 13B, 199034, St. Petersburg, Russia
| | - R R LaPierre
- Department of Engineering Physics, McMaster University, Hamilton, ON L8S4L7, Canada
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5
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Yuan X, Wang N, Tian Z, Zhang F, Li L, Lockrey M, He J, Jagadish C, Tan HH. Facet-dependent growth of InAsP quantum wells in InP nanowire and nanomembrane arrays. NANOSCALE HORIZONS 2020; 5:1530-1537. [PMID: 32955074 DOI: 10.1039/d0nh00410c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Selective area epitaxy is a powerful growth technique that has been used to produce III-V semiconductor nanowire and nanomembrane arrays for photonic and electronic applications. The incorporation of a heterostructure such as quantum wells (QWs) brings new functionality and further broadens their applications. Using InP nanowires and nanomembranes as templates, we investigate the growth of InAsP QWs on these pure wurtzite nanostructures. InAsP QWs grow both axially and laterally on the nanowires and nanomembranes, forming a zinc blende phase axially and wurtzite phase on the sidewalls. On the non-polar {11[combining macron]00} sidewalls, the radial QW selectively grows on one sidewall which is located at the semi-polar 〈112[combining macron]〉 A side of the axial QW, causing the shape evolution of the nanowires from hexagonal to triangular cross section. For nanomembranes with {11[combining macron]00} sidewalls, the radial QW grows asymmetrically on the {11[combining macron]00} facet, destroying their symmetry. In comparison, nanomembranes with {112[combining macron]0} sidewalls are shown to be an ideal template for the growth of InAsP QWs, thanks to the uniform QW formation. These QWs emit strongly in the near IR region at room temperature and their emission can be tuned by changing their thickness or composition. These findings enrich our understanding of the QW growth, which provides new insights for heterostructure design in other III-V nanostructures.
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Affiliation(s)
- Xiaoming Yuan
- Hunan Key Laboratory of Super Microstructure and Ultrafast Process, School of Physics and Electronics, Central South University, Changsha, Hunan 410083, P. R. China.
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6
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Saket O, Himwas C, Piazza V, Bayle F, Cattoni A, Oehler F, Patriarche G, Travers L, Collin S, Julien FH, Harmand JC, Tchernycheva M. Nanoscale electrical analyses of axial-junction GaAsP nanowires for solar cell applications. NANOTECHNOLOGY 2020; 31:145708. [PMID: 31846937 DOI: 10.1088/1361-6528/ab62c9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Axial p-n and p-i-n junctions in GaAs0.7P0.3 nanowires are demonstrated and analyzed using electron beam induced current microscopy. Organized self-catalyzed nanowire arrays are grown by molecular beam epitaxy on nanopatterned Si substrates. The nanowires are doped using Be and Si impurities to obtain p- and n-type conductivity, respectively. A method to determine the doping type by analyzing the induced current in the vicinity of a Schottky contact is proposed. It is demonstrated that for the applied growth conditions using Ga as a catalyst, Si doping induces an n-type conductivity contrary to the GaAs self-catalyzed nanowire case, where Si was reported to yield a p-type doping. Active axial nanowire p-n junctions having a homogeneous composition along the axis are synthesized and the carrier concentration and minority carrier diffusion lengths are measured. To the best of our knowledge, this is the first report of axial p-n junctions in self-catalyzed GaAsP nanowires.
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Affiliation(s)
- Omar Saket
- Centre de Nanosciences et de Nanotechnologies, UMR 9001 CNRS, Univ. Paris Sud, Univ. Paris-Saclay, 10 Boulevard Thomas Gobert, F-91120 Palaiseau Cedex, France
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7
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Barrigón E, Heurlin M, Bi Z, Monemar B, Samuelson L. Synthesis and Applications of III-V Nanowires. Chem Rev 2019; 119:9170-9220. [PMID: 31385696 DOI: 10.1021/acs.chemrev.9b00075] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Low-dimensional semiconductor materials structures, where nanowires are needle-like one-dimensional examples, have developed into one of the most intensely studied fields of science and technology. The subarea described in this review is compound semiconductor nanowires, with the materials covered limited to III-V materials (like GaAs, InAs, GaP, InP,...) and III-nitride materials (GaN, InGaN, AlGaN,...). We review the way in which several innovative synthesis methods constitute the basis for the realization of highly controlled nanowires, and we combine this perspective with one of how the different families of nanowires can contribute to applications. One reason for the very intense research in this field is motivated by what they can offer to main-stream semiconductors, by which ultrahigh performing electronic (e.g., transistors) and photonic (e.g., photovoltaics, photodetectors or LEDs) technologies can be merged with silicon and CMOS. Other important aspects, also covered in the review, deals with synthesis methods that can lead to dramatic reduction of cost of fabrication and opportunities for up-scaling to mass production methods.
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Affiliation(s)
- Enrique Barrigón
- Division of Solid State Physics and NanoLund , Lund University , Box 118, 22100 Lund , Sweden
| | - Magnus Heurlin
- Division of Solid State Physics and NanoLund , Lund University , Box 118, 22100 Lund , Sweden.,Sol Voltaics AB , Scheelevägen 63 , 223 63 Lund , Sweden
| | - Zhaoxia Bi
- Division of Solid State Physics and NanoLund , Lund University , Box 118, 22100 Lund , Sweden
| | - Bo Monemar
- Division of Solid State Physics and NanoLund , Lund University , Box 118, 22100 Lund , Sweden
| | - Lars Samuelson
- Division of Solid State Physics and NanoLund , Lund University , Box 118, 22100 Lund , Sweden
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8
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Abstract
Semiconductor nanowires have attracted extensive interest as one of the best-defined classes of nanoscale building blocks for the bottom-up assembly of functional electronic and optoelectronic devices over the past two decades. The article provides a comprehensive review of the continuing efforts in exploring semiconductor nanowires for the assembly of functional nanoscale electronics and macroelectronics. Specifically, we start with a brief overview of the synthetic control of various semiconductor nanowires and nanowire heterostructures with precisely controlled physical dimension, chemical composition, heterostructure interface, and electronic properties to define the material foundation for nanowire electronics. We then summarize a series of assembly strategies developed for creating well-ordered nanowire arrays with controlled spatial position, orientation, and density, which are essential for constructing increasingly complex electronic devices and circuits from synthetic semiconductor nanowires. Next, we review the fundamental electronic properties and various single nanowire transistor concepts. Combining the designable electronic properties and controllable assembly approaches, we then discuss a series of nanoscale devices and integrated circuits assembled from nanowire building blocks, as well as a unique design of solution-processable nanowire thin-film transistors for high-performance large-area flexible electronics. Last, we conclude with a brief perspective on the standing challenges and future opportunities.
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Affiliation(s)
- Chuancheng Jia
- Department of Chemistry and Biochemistry , University of California, Los Angeles , Los Angeles , California 90095 , United States
| | - Zhaoyang Lin
- Department of Chemistry and Biochemistry , University of California, Los Angeles , Los Angeles , California 90095 , United States
| | - Yu Huang
- Department of Materials Science and Engineering , University of California, Los Angeles , Los Angeles , California 90095 , United States.,California NanoSystems Institute , University of California, Los Angeles , Los Angeles , California 90095 , United States
| | - Xiangfeng Duan
- Department of Chemistry and Biochemistry , University of California, Los Angeles , Los Angeles , California 90095 , United States.,California NanoSystems Institute , University of California, Los Angeles , Los Angeles , California 90095 , United States
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9
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Himwas C, Collin S, Chen HL, Patriarche G, Oehler F, Travers L, Saket O, Julien FH, Harmand JC, Tchernycheva M. Correlated optical and structural analyses of individual GaAsP/GaP core-shell nanowires. NANOTECHNOLOGY 2019; 30:304001. [PMID: 30965307 DOI: 10.1088/1361-6528/ab1760] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We report on the structural and optical properties of GaAs0.7P0.3/GaP core-shell nanowires (NWs) for future photovoltaic applications. The NWs are grown by self-catalyzed molecular beam epitaxy. Scanning transmission electron microscopy (STEM) analyses demonstrate that the GaAsP NW core develops an inverse-tapered shape with a formation of an unintentional GaAsP shell having a lower P content. Without surface passivation, this unintentional shell produces no luminescence because of strong surface recombination. However, passivation of the surface with a GaP shell leads to the appearance of a secondary peak in the luminescence spectrum arising from this unintentional shell. The attribution of the luminescence peaks is confirmed by correlated cathodoluminescence and STEM analyses of the same NW.
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Affiliation(s)
- C Himwas
- Centre de Nanosciences et de Nanotechnologies, UMR 9001 CNRS, Univ. Paris Sud, Univ. Paris-Saclay, 10 Boulevard Thomas Gobert, F-91120 Palaiseau Cedex, France. Semiconductor Device Research Laboratory, Department of Electrical Engineering, Faculty of Engineering, Chulalongkorn University, 254 Phayathai Road, Bangkok 10330, Thailand
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10
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de Lépinau R, Scaccabarozzi A, Patriarche G, Travers L, Collin S, Cattoni A, Oehler F. Evidence and control of unintentional As-rich shells in GaAs 1-x P x nanowires. NANOTECHNOLOGY 2019; 30:294003. [PMID: 31032812 DOI: 10.1088/1361-6528/ab14c1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We report on the detailed composition of ternary GaAsP nanowires (NWs) grown using self-catalyzed vapor-liquid-solid (VLS) growth by molecular beam epitaxy. We evidence the formation of an unintentional shell, which enlarges by vapor-solid growth concurrently to the main VLS-grown core. The NW core and unintentional shell have typically different chemical compositions if no effort is made to adjust the growth conditions. The compositions can be made equal by changing the substrate temperature and the P/As flux ratio in the vapor phase. In all cases, we still observe the existence of a P-rich interface between the GaAsP NW core and the unintentional shell, even if favorable growth conditions are used.
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Affiliation(s)
- Romaric de Lépinau
- IPVF, Institut Photovoltaïque d'Île-de-France, F-91120 Palaiseau, France. C2N, Centre de Nanosciences et de Nanotechnologies, UMR 9001 CNRS, Univ. Paris Sud, Univ. Paris-Saclay, F-91120 Palaiseau, France
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11
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Zhang Y, Davis G, Fonseka HA, Velichko A, Gustafsson A, Godde T, Saxena D, Aagesen M, Parkinson PW, Gott JA, Huo S, Sanchez AM, Mowbray DJ, Liu H. Highly Strained III-V-V Coaxial Nanowire Quantum Wells with Strong Carrier Confinement. ACS NANO 2019; 13:5931-5938. [PMID: 31067033 PMCID: PMC7007272 DOI: 10.1021/acsnano.9b01775] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 05/08/2019] [Indexed: 06/01/2023]
Abstract
Coaxial quantum wells (QWs) are ideal candidates for nanowire (NW) lasers, providing strong carrier confinement and allowing close matching of the cavity mode and gain medium. We report a detailed structural and optical study and the observation of lasing for a mixed group-V GaAsP NW with GaAs QWs. This system offers a number of potential advantages in comparison to previously studied common group-V structures ( e. g., AlGaAs/GaAs) including highly strained binary GaAs QWs, the absence of a lower band gap core region, and deep carrier potential wells. Despite the large lattice mismatch (∼1.7%), it is possible to grow defect-free GaAs coaxial QWs with high optical quality. The large band gap difference results in strong carrier confinement, and the ability to apply a high degree of compressive strain to the GaAs QWs is also expected to be beneficial for laser performance. For a non-fully optimized structure containing three QWs, we achieve low-temperature lasing with a low external (internal) threshold of 20 (0.9) μJ/cm2/pulse. In addition, a very narrow lasing line width of ∼0.15 nm is observed. These results extend the NW laser structure to coaxial III-V-V QWs, which are highly suitable as the platform for NW emitters.
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Affiliation(s)
- Yunyan Zhang
- Department
of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
| | - George Davis
- Department
of Physics and Astronomy and the Photon Science Institute, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - H. Aruni Fonseka
- Department
of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Anton Velichko
- Department
of Physics and Astronomy and the Photon Science Institute, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - Anders Gustafsson
- Solid
State Physics and NanoLund, Lund University, Box 118, SE-221 00 Lund, Sweden
| | - Tillmann Godde
- Department
of Physics and Astronomy and the Photon Science Institute, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - Dhruv Saxena
- The
Blackett Laboratory, Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom
| | - Martin Aagesen
- Danish
Defence Research Center, Lautrupbjerg 1-5, 2750 Ballerup, Denmark
| | - Patrick W. Parkinson
- School
of Physics and Astronomy and the Photon Science Institute, University of Manchester, Manchester M13 9PL, United Kingdom
| | - James A. Gott
- Department
of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Suguo Huo
- London
Centre for Nanotechnology, University College
London, London WC1H 0AH, United Kingdom
| | - Ana M. Sanchez
- Department
of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - David J. Mowbray
- Department
of Physics and Astronomy and the Photon Science Institute, University of Sheffield, Sheffield S3 7RH, United Kingdom
| | - Huiyun Liu
- Department
of Electronic and Electrical Engineering, University College London, London WC1E 7JE, United Kingdom
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12
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Zhang Y, Saxena D, Aagesen M, Liu H. Toward electrically driven semiconductor nanowire lasers. NANOTECHNOLOGY 2019; 30:192002. [PMID: 30658345 DOI: 10.1088/1361-6528/ab000d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Semiconductor nanowire (NW) lasers are highly promising for making new-generation coherent light sources with the advantages of ultra-small size, high efficiency, easy integration and low cost. Over the past 15 years, this area of research has been developing rapidly, with extensive reports of optically pumped lasing in various inorganic and organic semiconductor NWs. Motivated by these developments, substantial efforts are being made to make NW lasers electrically pumped, which is necessary for their practical implementation. In this review, we first categorize NW lasers according to their lasing wavelength and wavelength tunability. Then, we summarize the methods used for achieving single-mode lasing in NWs. After that, we review reports on lasing threshold reduction and the realization of electrically pumped NW lasers. Finally, we offer our perspective on future improvements and trends.
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Affiliation(s)
- Yunyan Zhang
- Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE, United Kingdom
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13
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Abstract
Solar energy is abundant, clean, and renewable, making it an ideal energy source. Solar cells are a good option to harvest this energy. However, it is difficult to balance the cost and efficiency of traditional thin-film solar cells, whereas nanowires (NW) are far superior in making high-efficiency low-cost solar cells. Therefore, the NW solar cell has attracted great attention in recent years and is developing rapidly. Here, we review the great advantages, recent breakthroughs, novel designs, and remaining challenges of NW solar cells. Special attention is given to (but not limited to) the popular semiconductor NWs for solar cells, in particular, Si, GaAs(P), and InP.
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14
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Valente J, Godde T, Zhang Y, Mowbray DJ, Liu H. Light-Emitting GaAs Nanowires on a Flexible Substrate. NANO LETTERS 2018; 18:4206-4213. [PMID: 29894627 DOI: 10.1021/acs.nanolett.8b01100] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Semiconductor nanowire-based devices are among the most promising structures used to meet the current challenges of electronics, optics and photonics. Due to their high surface-to-volume ratio and excellent optical and electrical properties, devices with low power, high efficiency and high density can be created. This is of major importance for environmental issues and economic impact. Semiconductor nanowires have been used to fabricate high performance devices, including detectors, solar cells and transistors. Here, we demonstrate a technique for transferring large-area nanowire arrays to flexible substrates while retaining their excellent quantum efficiency in emission. Starting with a defect-free self-catalyzed molecular beam epitaxy (MBE) sample grown on a Si substrate, GaAs core-shell nanowires are embedded in a dielectric, removed by reactive ion etching and transferred to a plastic substrate. The original structural and optical properties, including the vertical orientation, of the nanowires are retained in the final plastic substrate structure. Nanowire emission is observed for all stages of the fabrication process, with a higher emission intensity observed for the final transferred structure, consistent with a reduction in nonradiative recombination via the modification of surface states. This transfer process could form the first critical step in the development of flexible nanowire-based light-emitting devices.
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Affiliation(s)
- João Valente
- Department of Electronic and Electrical Engineering , University College London , London WC1E 7JE , United Kingdom
| | - Tillmann Godde
- Department of Physics and Astronomy , University of Sheffield , Sheffield S3 7RH , United Kingdom
| | - Yunyan Zhang
- Department of Electronic and Electrical Engineering , University College London , London WC1E 7JE , United Kingdom
| | - David J Mowbray
- Department of Physics and Astronomy , University of Sheffield , Sheffield S3 7RH , United Kingdom
| | - Huiyun Liu
- Department of Electronic and Electrical Engineering , University College London , London WC1E 7JE , United Kingdom
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15
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Ali H, Zhang Y, Tang J, Peng K, Sun S, Sun Y, Song F, Falak A, Wu S, Qian C, Wang M, Zuo Z, Jin KJ, Sanchez AM, Liu H, Xu X. High-Responsivity Photodetection by a Self-Catalyzed Phase-Pure p-GaAs Nanowire. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1704429. [PMID: 29611286 DOI: 10.1002/smll.201704429] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 02/02/2018] [Indexed: 05/25/2023]
Abstract
Defects are detrimental for optoelectronics devices, such as stacking faults can form carrier-transportation barriers, and foreign impurities (Au) with deep-energy levels can form carrier traps and nonradiative recombination centers. Here, self-catalyzed p-type GaAs nanowires (NWs) with a pure zinc blende (ZB) structure are first developed, and then a photodetector made from these NWs is fabricated. Due to the absence of stacking faults and suppression of large amount of defects with deep energy levels, the photodetector exhibits room-temperature high photoresponsivity of 1.45 × 105 A W-1 and excellent specific detectivity (D*) up to 1.48 × 1014 Jones for a low-intensity light signal of wavelength 632.8 nm, which outperforms previously reported NW-based photodetectors. These results demonstrate these self-catalyzed pure-ZB GaAs NWs to be promising candidates for optoelectronics applications.
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Affiliation(s)
- Hassan Ali
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Yunyan Zhang
- Department of Electronics and Electrical Engineering, University College London, London, WC1E 7JE, UK
| | - Jing Tang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Kai Peng
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Sibai Sun
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Yue Sun
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Feilong Song
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Attia Falak
- National Centre for Nanoscience and Technology, Chinese Academy of Sciences, Beijing, 100190, China
- Department of Physics, University of the Punjab, Quaid-e-Azam Campus, Lahore, 54000, Pakistan
| | - Shiyao Wu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Chenjiang Qian
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Meng Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Zhanchun Zuo
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Kui-Juan Jin
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Ana M Sanchez
- Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
| | - Huiyun Liu
- Department of Electronics and Electrical Engineering, University College London, London, WC1E 7JE, UK
| | - Xiulai Xu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
- CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing, 100190, China
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16
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Zhang Y, Sun Z, Sanchez AM, Ramsteiner M, Aagesen M, Wu J, Kim D, Jurczak P, Huo S, Lauhon LJ, Liu H. Doping of Self-Catalyzed Nanowires under the Influence of Droplets. NANO LETTERS 2018; 18:81-87. [PMID: 29206466 DOI: 10.1021/acs.nanolett.7b03366] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Controlled and reproducible doping is essential for nanowires (NWs) to realize their functions. However, for the widely used self-catalyzed vapor-liquid-solid (VLS) growth mode, the doping mechanism is far from clear, as the participation of the nanoscale liquid phase makes the doping environment highly complex and significantly different from that of the thin film growth. Here, the doping mechanism of self-catalyzed NWs and the influence of self-catalytic droplets on the doping process are systematically studied using beryllium (Be) doped GaAs NWs. Be atoms are found for the first time to be incorporated into NWs predominantly through the Ga droplet that is observed to be beneficial for setting up thermodynamic equilibrium at the growth front. Be dopants are thus substitutional on Ga sites and redundant Be atoms are accumulated inside the Ga droplets when NWs are saturated, leading to the change of the Ga droplet properties and causing the growth of phase-pure zincblende NWs. This study is an essential step toward the design and fabrication of nanowire devices.
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Affiliation(s)
- Yunyan Zhang
- Department of Electronic and Electrical Engineering, University College London , London WC1E 7JE, United Kingdom
| | - Zhiyuan Sun
- Department of Materials Science and Engineering, Northwestern University , 2220 Campus Drive, Evanston, Illinois 60208-3108, United States
| | - Ana M Sanchez
- Department of Physics, University of Warwick , Coventry CV4 7AL, United Kingdom
| | - Manfred Ramsteiner
- Paul-Drude-Institut für Festkörperelektronik , Hausvogteiplatz 5-7, 10117 Berlin, Germany
| | - Martin Aagesen
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Jiang Wu
- Department of Electronic and Electrical Engineering, University College London , London WC1E 7JE, United Kingdom
| | - Dongyoung Kim
- Department of Electronic and Electrical Engineering, University College London , London WC1E 7JE, United Kingdom
| | - Pamela Jurczak
- Department of Electronic and Electrical Engineering, University College London , London WC1E 7JE, United Kingdom
| | - Suguo Huo
- London Centre for Nanotechnology, University College London , London WC1H 0AH, United Kingdom
| | - Lincoln J Lauhon
- Department of Materials Science and Engineering, Northwestern University , 2220 Campus Drive, Evanston, Illinois 60208-3108, United States
| | - Huiyun Liu
- Department of Electronic and Electrical Engineering, University College London , London WC1E 7JE, United Kingdom
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17
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Zhang Y, Fonseka HA, Aagesen M, Gott JA, Sanchez AM, Wu J, Kim D, Jurczak P, Huo S, Liu H. Growth of Pure Zinc-Blende GaAs(P) Core-Shell Nanowires with Highly Regular Morphology. NANO LETTERS 2017; 17:4946-4950. [PMID: 28758401 DOI: 10.1021/acs.nanolett.7b02063] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The growth of self-catalyzed core-shell nanowires (NWs) is investigated systematically using GaAs(P) NWs. The defects in the core NW are found to be detrimental for the shell growth. These defects are effectively eliminated by introducing beryllium (Be) doping during the NW core growth and hence forming Be-Ga alloy droplets that can effectively suppress the WZ nucleation and facilitate the droplet consumption. Shells with pure zinc-blende crystal quality and highly regular morphology are successfully grown on the defect-free NW cores and demonstrated an enhancement of one order of magnitude for room-temperature emission compared to that of the defective shells. These results provide useful information on guiding the growth of high-quality shell, which can greatly enhance the NW device performance.
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Affiliation(s)
- Yunyan Zhang
- Department of Electronic and Electrical Engineering, University College , London WC1E 7JE, United Kingdom
| | - H Aruni Fonseka
- Department of Physics, University of Warwick , Coventry CV4 7AL, United Kingdom
| | - Martin Aagesen
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen, Denmark
| | - James A Gott
- Department of Physics, University of Warwick , Coventry CV4 7AL, United Kingdom
| | - Ana M Sanchez
- Department of Physics, University of Warwick , Coventry CV4 7AL, United Kingdom
| | - Jiang Wu
- Department of Electronic and Electrical Engineering, University College , London WC1E 7JE, United Kingdom
| | - Dongyoung Kim
- Department of Electronic and Electrical Engineering, University College , London WC1E 7JE, United Kingdom
| | - Pamela Jurczak
- Department of Electronic and Electrical Engineering, University College , London WC1E 7JE, United Kingdom
| | - Suguo Huo
- London Centre for Nanotechnology, University College , London WC1H 0AH, United Kingdom
| | - Huiyun Liu
- Department of Electronic and Electrical Engineering, University College , London WC1E 7JE, United Kingdom
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18
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Zhang Y, Sanchez AM, Sun Y, Wu J, Aagesen M, Huo S, Kim D, Jurczak P, Xu X, Liu H. Influence of Droplet Size on the Growth of Self-Catalyzed Ternary GaAsP Nanowires. NANO LETTERS 2016; 16:1237-1243. [PMID: 26708002 DOI: 10.1021/acs.nanolett.5b04554] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The influences of droplet size on the growth of self-catalyzed ternary nanowires (NWs) were studied using GaAsP NWs. The size-induced Gibbs-Thomson (GT) effect makes the smaller catalytic droplets have lower effective supersaturations and hence slower nucleation rates than the larger ones. Large variation in droplet size thus led to the growth of NWs with low uniformity, while a good size uniformity of droplets resulted in the production of highly uniform NWs. Moreover, thinner NWs were observed to be richer in P, indicating that P is more resistant to the GT effect than As because of a higher chemical potential inside Ga droplets. These results provide useful information for understanding the mechanisms of self-catalyzed III-V NW nucleation and growth with the important ternary III-V material systems.
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Affiliation(s)
- Yunyan Zhang
- Department of Electronic and Electrical Engineering, University College London , London WC1E 7JE, United Kingdom
| | - Ana M Sanchez
- Department of Physics, University of Warwick , Coventry CV4 7AL, United Kingdom
| | - Yue Sun
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences , Beijing 100190, People's Republic of China
| | - Jiang Wu
- Department of Electronic and Electrical Engineering, University College London , London WC1E 7JE, United Kingdom
| | - Martin Aagesen
- Gasp Solar ApS, Gregersensvej 7, Taastrup DK-2630, Denmark
| | - Suguo Huo
- London Centre for Nanotechnology, University College London , London WC1H 0AH, United Kingdom
| | - Dongyoung Kim
- Department of Electronic and Electrical Engineering, University College London , London WC1E 7JE, United Kingdom
| | - Pamela Jurczak
- Department of Electronic and Electrical Engineering, University College London , London WC1E 7JE, United Kingdom
| | - Xiulai Xu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences , Beijing 100190, People's Republic of China
| | - Huiyun Liu
- Department of Electronic and Electrical Engineering, University College London , London WC1E 7JE, United Kingdom
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19
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Ren D, Dheeraj DL, Jin C, Nilsen JS, Huh J, Reinertsen JF, Munshi AM, Gustafsson A, van Helvoort ATJ, Weman H, Fimland BO. New Insights into the Origins of Sb-Induced Effects on Self-Catalyzed GaAsSb Nanowire Arrays. NANO LETTERS 2016; 16:1201-1209. [PMID: 26726825 DOI: 10.1021/acs.nanolett.5b04503] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Ternary semiconductor nanowire arrays enable scalable fabrication of nano-optoelectronic devices with tunable bandgap. However, the lack of insight into the effects of the incorporation of Vy element results in lack of control on the growth of ternary III-V(1-y)Vy nanowires and hinders the development of high-performance nanowire devices based on such ternaries. Here, we report on the origins of Sb-induced effects affecting the morphology and crystal structure of self-catalyzed GaAsSb nanowire arrays. The nanowire growth by molecular beam epitaxy is changed both kinetically and thermodynamically by the introduction of Sb. An anomalous decrease of the axial growth rate with increased Sb2 flux is found to be due to both the indirect kinetic influence via the Ga adatom diffusion induced catalyst geometry evolution and the direct composition modulation. From the fundamental growth analyses and the crystal phase evolution mechanism proposed in this Letter, the phase transition/stability in catalyst-assisted ternary III-V-V nanowire growth can be well explained. Wavelength tunability with good homogeneity of the optical emission from the self-catalyzed GaAsSb nanowire arrays with high crystal phase purity is demonstrated by only adjusting the Sb2 flux.
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Affiliation(s)
| | - Dasa L Dheeraj
- CrayoNano AS, Otto Nielsens vei 12, NO-7052 Trondheim, Norway
| | - Chengjun Jin
- Center for Atomic-Scale Materials Design, Department of Physics, Technical University of Denmark , DK-2800 Kongens Lyngby, Denmark
| | | | | | | | - A Mazid Munshi
- CrayoNano AS, Otto Nielsens vei 12, NO-7052 Trondheim, Norway
| | - Anders Gustafsson
- Solid State Physics and NanoLund, Lund University , Box 118, SE-22100 Lund, Sweden
| | | | - Helge Weman
- CrayoNano AS, Otto Nielsens vei 12, NO-7052 Trondheim, Norway
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20
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Farrell AC, Lee WJ, Senanayake P, Haddad MA, Prikhodko SV, Huffaker DL. High-Quality InAsSb Nanowires Grown by Catalyst-Free Selective-Area Metal-Organic Chemical Vapor Deposition. NANO LETTERS 2015; 15:6614-6619. [PMID: 26422559 DOI: 10.1021/acs.nanolett.5b02389] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report on the first demonstration of InAs1-xSbx nanowires grown by catalyst-free selective-area metal-organic chemical vapor deposition (SA-MOCVD). Antimony composition as high as 15 % is achieved, with strong photoluminescence at all compositions. The quality of the material is assessed by comparing the photoluminescence (PL) peak full-width at half-max (fwhm) of the nanowires to that of epitaxially grown InAsSb thin films on InAs. We find that the fwhm of the nanowires is only a few meV broader than epitaxial films, and a similar trend of relatively constant fwhm for increasing antimony composition is observed. Furthermore, the PL peak energy shows a strong dependence on temperature, suggesting wave-vector conserving transitions are responsible for the observed PL in spite of lattice mismatched growth on InAs substrate. This study shows that high-quality InAsSb nanowires can be grown by SA-MOCVD on lattice mismatched substrate, resulting in material suitable for infrared detectors and high-performance nanoelectronic devices.
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Affiliation(s)
- Alan C Farrell
- Electrical Engineering Department, ‡Materials Science Department, and §California NanoSystems Institute, University of California at Los Angeles , Los Angeles, California 90095, United States
| | - Wook-Jae Lee
- Electrical Engineering Department, ‡Materials Science Department, and §California NanoSystems Institute, University of California at Los Angeles , Los Angeles, California 90095, United States
| | - Pradeep Senanayake
- Electrical Engineering Department, ‡Materials Science Department, and §California NanoSystems Institute, University of California at Los Angeles , Los Angeles, California 90095, United States
| | - Michael A Haddad
- Electrical Engineering Department, ‡Materials Science Department, and §California NanoSystems Institute, University of California at Los Angeles , Los Angeles, California 90095, United States
| | - Sergey V Prikhodko
- Electrical Engineering Department, ‡Materials Science Department, and §California NanoSystems Institute, University of California at Los Angeles , Los Angeles, California 90095, United States
| | - Diana L Huffaker
- Electrical Engineering Department, ‡Materials Science Department, and §California NanoSystems Institute, University of California at Los Angeles , Los Angeles, California 90095, United States
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21
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Zhu M, Aryal GH, Zhang N, Zhang H, Su X, Schmehl R, Liu X, Hu J, Wei J, Jayawickramarajah J. Host-guest interactions derived multilayer perylene diimide thin film constructed on a scaffolding porphyrin monolayer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:578-586. [PMID: 25495000 DOI: 10.1021/la504297w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The development of methods to grow well-ordered chromophore thin films on solid substrates is of importance because such surface-associated arrays have potential applications in the generation of functional electronic and optical materials and devices. In this article, we demonstrate a straightforward layer-by-layer (LBL) supramolecular deposition strategy to prepare numerous layers (up to 19) of functionalized perylene diimide (PDI) chromophores built upon a covalent scaffolding multivalent porphyrin monolayer. Our thin film formation strategy employs water as the immersion solvent and exploits the β-cyclodextrin-adamantane host-guest couple in addition to PDI based aromatic stacking. Within the resultant film the porphyrin scaffold is oriented close to parallel to the glass substrate while the PDI chromophores are aligned closer to the surface normal. Together, the porphyrin monolayer and the multi-PDI layers exhibit a large absorption bandwidth in the visible spectrum. Importantly, because a self-assembly strategy was utilized, when a single monolayer of PDI is deposited on the porphyrin scaffolding layer, this PDI monolayer can be readily disassembled by washing with DMF leading to the regeneration of the porphyrin monolayer. The PDI thin film can subsequently be regrown from the regenerated porphyrin surface. The reported LBL strategy will be of broad interest for researchers developing well-organized chromophoric films and materials due to its simplicity as well as the added advantage of being performed in sustainable and cost-effective aqueous media.
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Affiliation(s)
- Mengyuan Zhu
- Department of Chemistry and ‡Department of Physics & Engineering Physics, Tulane University , New Orleans, Louisiana 70118, United States
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