1
|
Sano KH, Ono Y, Tobinaga R, Imamura Y, Hayashi Y, Yanagitani T. Atmospheric Gas-Phase Catalyst Etching of SiO 2 for Deep Microfabrication Using HF Gas and Patterned Photoresist. ACS APPLIED MATERIALS & INTERFACES 2024; 16:22657-22664. [PMID: 38651281 PMCID: PMC11071037 DOI: 10.1021/acsami.4c01291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/31/2024] [Accepted: 04/12/2024] [Indexed: 04/25/2024]
Abstract
Micro/nanoscale structure fabrication is an important process for designing miniaturized devices. Recently, three-dimensional (3D) integrated circuits using SiO2 via-holes interlayer filling by copper have attracted attention to extend the lifetime of Moore's law. However, the fabrication of vertical and smooth-sidewall via-hole structures on SiO2 has not been achieved using the conventional dry etching method due to the limitation of the selective etching ratio of SiO2 and hard mask materials. In this study, we developed a unique method for the deep anisotropic dry etching of SiO2 using atmospheric gas-phase HF and a patterned photoresist. The hydroxyl groups in the photoresist catalyzed the HF gas-phase dry etching of SiO2 at high-temperature conditions. Therefore, fabrication of vertical with smooth-sidewall deep microstructures was demonstrated in the photoresist-covered area on SiO2 at a processing rate of 1.3 μm/min, which is 2-3 times faster than the conventional dry etching method. Additionally, the chemical reaction pathway in the photoresist-covered area on SiO2 with HF gas was revealed via density functional theory (DFT) calculations. This simple and high-speed microfabrication process will expand the commercial application scope of next-generation microfabricated SiO2-based devices.
Collapse
Affiliation(s)
- Ko-hei Sano
- Graduate
School of Advanced Science and Engineering, Waseda University, Tokyo 169-8555, Japan
- Innovative
Technology Laboratories, AGC Incorporated, Kanagawa 230-0045, Japan
| | - Yoshitaka Ono
- Innovative
Technology Laboratories, AGC Incorporated, Kanagawa 230-0045, Japan
| | - Ryosuke Tobinaga
- Innovative
Technology Laboratories, AGC Incorporated, Kanagawa 230-0045, Japan
| | - Yutaka Imamura
- Innovative
Technology Laboratories, AGC Incorporated, Kanagawa 230-0045, Japan
| | - Yasuo Hayashi
- Innovative
Technology Laboratories, AGC Incorporated, Kanagawa 230-0045, Japan
| | - Takahiko Yanagitani
- Graduate
School of Advanced Science and Engineering, Waseda University, Tokyo 169-8555, Japan
- Kagami
Memorial Research Institute for Material Science and Technology, Waseda University, Tokyo 169-0051, Japan
- JST
CREST, Saitama 332-0012, Japan
- JST
FOREST, Saitama 332-0012, Japan
| |
Collapse
|
2
|
Surdo S, Barillaro G. Voltage- and Metal-assisted Chemical Etching of Micro and Nano Structures in Silicon: A Comprehensive Review. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2400499. [PMID: 38644330 DOI: 10.1002/smll.202400499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/12/2024] [Indexed: 04/23/2024]
Abstract
Sculpting silicon at the micro and nano scales has been game-changing to mold bulk silicon properties and expand, in turn, applications of silicon beyond electronics, namely, in photonics, sensing, medicine, and mechanics, to cite a few. Voltage- and metal-assisted chemical etching (ECE and MaCE, respectively) of silicon in acidic electrolytes have emerged over other micro and nanostructuring technologies thanks to their unique etching features. ECE and MaCE have enabled the fabrication of novel structures and devices not achievable otherwise, complementing those feasible with the deep reactive ion etching (DRIE) technology, the gold standard in silicon machining. Here, a comprehensive review of ECE and MaCE for silicon micro and nano machining is provided. The chemistry and physics ruling the dissolution of silicon are dissected and similarities and differences between ECE and MaCE are discussed showing that they are the two sides of the same coin. The processes governing the anisotropic etching of designed silicon micro and nanostructures are analyzed, and the modulation of etching profile over depth is discussed. The preparation of micro- and nanostructures with tailored optical, mechanical, and thermo(electrical) properties is then addressed, and their applications in photonics, (bio)sensing, (nano)medicine, and micromechanical systems are surveyed. Eventually, ECE and MaCE are benchmarked against DRIE, and future perspectives are highlighted.
Collapse
Affiliation(s)
- Salvatore Surdo
- Dipartimento di Ingegneria dell'Informazione, Università di Pisa, via G. Caruso 16, Pisa, 56122, Italy
| | - Giuseppe Barillaro
- Dipartimento di Ingegneria dell'Informazione, Università di Pisa, via G. Caruso 16, Pisa, 56122, Italy
| |
Collapse
|
3
|
Wang Q, Yang W, Gao S, Chen W, Tang X, Zhang H, Liu B, Han G, Huang Y. GaN nanowires prepared by Cu-assisted photoelectron-chemical etching. NANOSCALE ADVANCES 2023; 5:2238-2243. [PMID: 37056620 PMCID: PMC10089075 DOI: 10.1039/d2na00889k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Accepted: 03/07/2023] [Indexed: 06/19/2023]
Abstract
A novel Cu-assisted photoelectron-chemical etching is proposed to fabricate GaN nanowires. The functional mechanism of assisted metals, etchant concentrations, and the addition of H2O2 was investigated based on theoretical analysis and experiments. The low-cost metal-assisted etchant (CuSO4) proved more favorable than the conventional noble one (AgNO3) for the preparation of GaN nanowires in this work. The formed Ag dendrite blocked the etching when adopting the Ag-assisted etchant, while the Cu-assisted one did not. Moreover, the etchant consisting of 0.01 M CuSO4 and 5 M HF was demonstrated to realize a relatively good surface morphology and fast etching rate. In addition, the common oxidant H2O2 introduced a quasi-stable configuration between the Cu deposition and dissolution, slowing down the formation of the GaN nanowires. The proposed Cu-assisted photoelectron-chemical etching with the advantages of low cost, room temperature, and controllability could offer a new way to fabricate GaN nano-devices.
Collapse
Affiliation(s)
- Qi Wang
- School of Optoelectronic Engineering, Chongqing University of Posts and Telecommunications Chongqing 400065 China
| | - Wen Yang
- School of Optoelectronic Engineering, Chongqing University of Posts and Telecommunications Chongqing 400065 China
| | - Sheng Gao
- School of Optoelectronic Engineering, Chongqing University of Posts and Telecommunications Chongqing 400065 China
| | - Weizhong Chen
- School of Optoelectronic Engineering, Chongqing University of Posts and Telecommunications Chongqing 400065 China
| | - Xiaosheng Tang
- School of Optoelectronic Engineering, Chongqing University of Posts and Telecommunications Chongqing 400065 China
| | - Hongsheng Zhang
- School of Optoelectronic Engineering, Chongqing University of Posts and Telecommunications Chongqing 400065 China
| | - Bin Liu
- School of Electronic Science and Engineering, Nanjing University Nanjing China
| | - Genquan Han
- School of Microelectronics, Xidian University Xi'an China
| | - Yi Huang
- School of Optoelectronic Engineering, Chongqing University of Posts and Telecommunications Chongqing 400065 China
| |
Collapse
|
4
|
Hu L, Wang J, Wang H, Zhang Y, Han J. Gold-Promoted Electrodeposition of Metal Sulfides on Silicon Nanowire Photocathodes To Enhance Solar-Driven Hydrogen Evolution. ACS APPLIED MATERIALS & INTERFACES 2023; 15:15449-15457. [PMID: 36921238 DOI: 10.1021/acsami.2c22423] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Constructing composite structures is the key to breaking the dilemma of slow reaction kinetics and easy oxidation on the surface of lightly doped p-type silicon nanowire (SiNW) array photocathodes. Electrodeposition is a convenient and fast technique to prepare composite photocathodes. However, the low conductivity of SiNWs limits the application of the electrodeposition technique in constructing composite structures. Herein, SiNWs were loaded with Au nanoparticles by chemical deposition to decrease the interfacial charge transfer resistance and increase active sites for the electrodeposition. Subsequently, co-catalysts CoS, MoS2, and Ni3S2 with excellent hydrogen evolution activity were successfully composited by electrodeposition on the surface of SiNWs/Au. The obtained core-shell structures exhibited excellent photoelectrochemical hydrogen evolution activity, which was contributed by the plasma property of Au and the abundant hydrogen evolution active sites of the co-catalysts. This work provided a simple and efficient solution for the preparation of lightly doped SiNW-based composite structures by electrodeposition.
Collapse
Affiliation(s)
- Lang Hu
- School of Environmental Science and Engineering, Yangzhou University, Yangzhou 225009, China
| | - Jiamin Wang
- School of Food Science and Engineering, Yangzhou University, Yangzhou 225009, China
| | - Honggui Wang
- School of Environmental Science and Engineering, Yangzhou University, Yangzhou 225009, China
| | - Ya Zhang
- School of Environmental Science and Engineering, Yangzhou University, Yangzhou 225009, China
| | - Jie Han
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225009, China
| |
Collapse
|
5
|
Xu H, Han L, Su JJ, Tian ZQ, Zhan D. Spatially-separated and photo-enhanced semiconductor corrosion processes for high-efficient and contamination-free electrochemical nanoimprint lithography. Sci China Chem 2022. [DOI: 10.1007/s11426-021-1194-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
6
|
Akan R, Vogt U. Optimization of Metal-Assisted Chemical Etching for Deep Silicon Nanostructures. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:2806. [PMID: 34835572 PMCID: PMC8619014 DOI: 10.3390/nano11112806] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/13/2021] [Accepted: 10/19/2021] [Indexed: 11/21/2022]
Abstract
High-aspect ratio silicon (Si) nanostructures are important for many applications. Metal-assisted chemical etching (MACE) is a wet-chemical method used for the fabrication of nanostructured Si. Two main challenges exist with etching Si structures in the nanometer range with MACE: keeping mechanical stability at high aspect ratios and maintaining a vertical etching profile. In this work, we investigated the etching behavior of two zone plate catalyst designs in a systematic manner at four different MACE conditions as a function of mechanical stability and etching verticality. The zone plate catalyst designs served as models for Si nanostructures over a wide range of feature sizes ranging from 850 nm to 30 nm at 1:1 line-to-space ratio. The first design was a grid-like, interconnected catalyst (brick wall) and the second design was a hybrid catalyst that was partly isolated, partly interconnected (fishbone). Results showed that the brick wall design was mechanically stable up to an aspect ratio of 30:1 with vertical Si structures at most investigated conditions. The fishbone design showed higher mechanical stability thanks to the Si backbone in the design, but on the other hand required careful control of the reaction kinetics for etching verticality. The influence of MACE reaction kinetics was identified by lowering the oxidant concentration, lowering the processing temperature and by isopropanol addition. We report an optimized MACE condition to achieve an aspect ratio of at least 100:1 at room temperature processing by incorporating isopropanol in the etching solution.
Collapse
Affiliation(s)
- Rabia Akan
- KTH Royal Institute of Technology, Department of Applied Physics, Albanova University Center, 106 91 Stockholm, Sweden
| | - Ulrich Vogt
- KTH Royal Institute of Technology, Department of Applied Physics, Albanova University Center, 106 91 Stockholm, Sweden
| |
Collapse
|
7
|
Li P, Lu J, Wang WY, Sui X, Zou C, Zhang Y, Wang J, Lin D, Lu Z, Song H, Fan X, Hao J, Li J, Liu W. Lattice distortion-enhanced superlubricity of (Mo, X)S 2 (X = Al, Ti, Cr and V) with moiré superlattice. NANOSCALE 2021; 13:16234-16243. [PMID: 34546276 DOI: 10.1039/d1nr02382a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Two-dimensional (2D) materials with the advantage of low interlayer shear strain are ultilized as lubricants in aerospace and precision manufacturing. Moiré superlattices (MSL), with attractive physical properties of electronic structures, interlayer hybridization and atomic forces, have been widely investigated in superlubricity, which is caused by elimination of interlayer lock-in by incommensurate atomic reconstruction. Although the foundations of superlubricity and the development of 2D lubricants via vanishing friction have been investigated, it is still important to comprehensively reveal the influence of MSL on the interlayer van der Waals (vdW) interactions of 2D lubricants. Here, the contributions of lattice distortions of solute-doped twisted bilayers (Mo, X)S2 (X = Al, Ti, V and Cr) to superlubricity are comprehensively investigated by high-throughput modelling and DFT-D2 calculations. It is revealed that the lattice distortion not only breaks the interlayer balance of repulsion and van der Waals interactions but also yields layer corrugation. These layer-corrugation-induced changes of the interlayer interactions and spacing distances are utilized to optimize lubricity, which matches with the experimental friction coefficients in the order of (Mo, Al)S2 > (Mo, Cr)S2 > MoS2 >(Mo, V)S2 >(Mo, Ti)S2. The evolutions of the band structures show an exponential relationship of the band edge width and layer deformations, paving a path to accelerate the development of advanced superlubricity materials via lattice distortions.
Collapse
Affiliation(s)
- Peixuan Li
- State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China
| | - Jiaqi Lu
- State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China
- School of Science, Shenyang Ligong University, Liaoning, 110159, China
| | - William Yi Wang
- State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China
- Chongqing Innovation Center of Northwestern Polytechnical Univerisity, 401135, Chongqing, China
| | - Xudong Sui
- State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Science, 730000, Lanzhou, China
| | - Chengxiong Zou
- State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China
- Chongqing Innovation Center of Northwestern Polytechnical Univerisity, 401135, Chongqing, China
| | - Ying Zhang
- State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China
| | - Jun Wang
- State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China
- Chongqing Innovation Center of Northwestern Polytechnical Univerisity, 401135, Chongqing, China
| | - Deye Lin
- CAEP Code Center for High Performance Numerical Simulation, Beijing, 100088, China
| | - Zhibin Lu
- State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Science, 730000, Lanzhou, China
| | - Haifeng Song
- Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing, 100088, China
| | - Xiaoli Fan
- State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China
| | - Junying Hao
- State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Science, 730000, Lanzhou, China
| | - Jinshan Li
- State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China
- Chongqing Innovation Center of Northwestern Polytechnical Univerisity, 401135, Chongqing, China
| | - Weimin Liu
- State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China
| |
Collapse
|
8
|
Xie R, Ning P, Qu G, Deng J, Li Z, Li Z, Li J. Preparation of proton block and highly conductive
AEM
by creating
PANI
dominated and hydrophobicity ion channels for sulfuric acid enrichment. POLYM ADVAN TECHNOL 2021. [DOI: 10.1002/pat.5243] [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)
- Ruosong Xie
- Faculty of Environmental Science and Engineering Kunming University of Science & Technology Kunming China
| | - Ping Ning
- Faculty of Environmental Science and Engineering Kunming University of Science & Technology Kunming China
- National‐Regional Engineering Center for Recovery of Waste Gases from Metallurgical and Chemical Industries Kunming Yunnan China
| | - Guangfei Qu
- Faculty of Environmental Science and Engineering Kunming University of Science & Technology Kunming China
- National‐Regional Engineering Center for Recovery of Waste Gases from Metallurgical and Chemical Industries Kunming Yunnan China
| | - Jijia Deng
- Faculty of Environmental Science and Engineering Kunming University of Science & Technology Kunming China
| | - Ziying Li
- Faculty of Environmental Science and Engineering Kunming University of Science & Technology Kunming China
| | - Zhishuncheng Li
- Faculty of Environmental Science and Engineering Kunming University of Science & Technology Kunming China
| | - Junyan Li
- Faculty of Environmental Science and Engineering Kunming University of Science & Technology Kunming China
- National‐Regional Engineering Center for Recovery of Waste Gases from Metallurgical and Chemical Industries Kunming Yunnan China
| |
Collapse
|
9
|
MATSUMOTO A, IWAMOTO K, SHIMADA Y, FURUKAWA K, MAJIMA S, YAE S. Formation and Dissolution of Mesoporous Layer during Metal-Particle-Assisted Etching of n-Type Silicon. ELECTROCHEMISTRY 2021. [DOI: 10.5796/electrochemistry.20-65159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Ayumu MATSUMOTO
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo
| | - Keishi IWAMOTO
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo
| | - Yuki SHIMADA
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo
| | - Kyohei FURUKAWA
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo
| | - Shun MAJIMA
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo
| | - Shinji YAE
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo
| |
Collapse
|
10
|
Jo JS, Choi J, Lee SH, Song C, Noh H, Jang JW. Mass Fabrication of 3D Silicon Nano-/Microstructures by Fab-Free Process Using Tip-Based Lithography. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2005036. [PMID: 33369134 DOI: 10.1002/smll.202005036] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 11/26/2020] [Indexed: 06/12/2023]
Abstract
Methods for the mass fabrication of 3D silicon (Si) microstructures with a 100 nm resolution are developed using scanning probe lithography (SPL) combined with metal-assisted chemical etching (MACE). Protruding Si structures, including Si nanowires of over 10 µm in length and atypical shaped Si nano- and micropillars, are obtained via the MACE of a patterned gold film (negative tone) on Si substrates by dip-pen nanolithography (DPN) with polymer or by nanoshaving alkanethiol self-assembled monolayers (SAMs). Furthermore, recessed Si structures with arbitrary patterning and channels less than 160 nm wide and hundreds of nanometers in depth are obtained via the MACE of a patterned gold film (positive tone) on Si substrates by alkanethiol DPN. As an example of applications using protruded Si structures, nanoimprinting in an area of up to a centimeter is demonstrated through 1D and 2D SPL combined with MACE. Similarly, submicrometer polydimethylsiloxane (PDMS) stamps are employed over millimeter-scale areas for applications using recessed Si structures. In particular, the mass production of arbitrarily shaped Si microparticles at submicrometer resolution is developed using silicon-on-insulator substrates, as demonstrated using optical microresonators, surface-enhanced Raman scattering templates, and smart microparticles for fluorescence signal coding.
Collapse
Affiliation(s)
- Jeong-Sik Jo
- Division of Physics and Semiconductor Science, Dongguk University, Seoul, 04620, Republic of Korea
| | - Jihoon Choi
- Department of Nano and Electronic Physics, Kookmin University, Seoul, 02707, Republic of Korea
| | - Seung-Hoon Lee
- Department of Chemistry, Duke University, Durham, NC, 27708, USA
| | - Changhoon Song
- Department of Physics, Pukyong National University, Busan, 48513, Republic of Korea
| | - Heeso Noh
- Department of Nano and Electronic Physics, Kookmin University, Seoul, 02707, Republic of Korea
| | - Jae-Won Jang
- Division of Physics and Semiconductor Science, Dongguk University, Seoul, 04620, Republic of Korea
| |
Collapse
|
11
|
Wendisch F, Rey M, Vogel N, Bourret GR. Large-Scale Synthesis of Highly Uniform Silicon Nanowire Arrays Using Metal-Assisted Chemical Etching. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2020; 32:9425-9434. [PMID: 33191979 PMCID: PMC7659364 DOI: 10.1021/acs.chemmater.0c03593] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 10/14/2020] [Indexed: 05/11/2023]
Abstract
The combination of metal-assisted chemical etching (MACE) with colloidal lithography has emerged as a simple and cost-effective approach to nanostructure silicon. It is especially efficient at synthesizing Si micro- and nanowire arrays using a catalytic metal mesh, which sinks into the silicon substrate during the etching process. The approach provides a precise control over the array geometry, without requiring expensive nanopatterning techniques. Although MACE is a high-throughput solution-based approach, achieving large-scale homogeneity can be challenging because of the instability of the metal catalyst when the experimental parameters are not set appropriately. Such instabilities can lead to metal film fracture, significantly damaging the substrate and thus compromising the nanowire array quality. Here, we report on the critical parameters that influence the stability of the metal catalyst layer for achieving large-scale homogeneous MACE: etchant composition, metal film thickness, adhesion layer thickness, nanowire diameter and pitch, metal film coverage, Si/Au/etchant interface length, and crystalline quality of the colloidal template (grain size and defects). Our results investigate the origin of the catalyst film fracture and reveal that MACE experiments should be optimized for each Si wire array geometry by keeping the etch rate below a certain threshold. We show that the Si/Au/etchant interface length also affects the etch rate and should thus be considered when optimizing the MACE experimental parameters. Finally, our results demonstrate that colloidal templates with small grain sizes (i.e., <100 μm2) can yield significant problems during the pattern transfer because of a high density of defects at the grain boundaries that negatively affects the metal film stability. As such, this work provides guidelines for the large-scale synthesis of Si micro- and nanowire arrays via MACE, relevant for both new and experienced researchers working with MACE.
Collapse
Affiliation(s)
- Fedja
J. Wendisch
- Department
of Chemistry and Physics of Materials, University
of Salzburg, Jakob Haringer Strasse 2A, A-5020 Salzburg, Austria
| | - Marcel Rey
- Institute
of Particle Technology, Friedrich-Alexander
University Erlangen-Nürnberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Nicolas Vogel
- Institute
of Particle Technology, Friedrich-Alexander
University Erlangen-Nürnberg, Cauerstrasse 4, 91058 Erlangen, Germany
| | - Gilles R. Bourret
- Department
of Chemistry and Physics of Materials, University
of Salzburg, Jakob Haringer Strasse 2A, A-5020 Salzburg, Austria
| |
Collapse
|
12
|
Adhila TK, Elangovan H, John S, Chattopadhyay K, Barshilia HC. Engineering the Microstructure of Silicon Nanowires by Controlling the Shape of the Metal Catalyst and Composition of the Etchant in a Two-Step MACE Process: An In-Depth Analysis of the Growth Mechanism. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:9388-9398. [PMID: 32687375 DOI: 10.1021/acs.langmuir.0c01164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In this work, slanted, kinked, and straight silicon nanowires (SiNWs) are fabricated on Si(111) and (100) substrates using a facile two-step metal-assisted chemical etching nanofabrication technique. We systematically investigated the effect of crystallography, morphology of Ag catalyst, and composition of etchant on the etch profile of Ag catalyst on Si(111) and (100) substrates. We found that the movement of AgNPs inside the Si is determined by physiochemical events such as Ag/Ag interaction, Ag/Si contact, and diffusion kinetics. Further, from detailed TEM and micro-Raman spectroscopy analyses, we demonstrate that the metal catalyst moves in the crystallographically preferred etching direction (viz., <100>) only when the interface effect is not predominant. Further, the metal-assisted chemical etching (MACE) system is highly stable at low-concentration plating and etching solutions, but at high concentrations, the system loses its stability and becomes highly random, leading to the movement of Ag catalyst in directions other than ⟨100⟩. In addition, our studies reveal that Ag nanostructures growth on Si(111) and (100) substrates through galvanic displacement is controlled by substrate symmetry and surface bond density. Finally, we demonstrate that by using an optimized balance between the Ag morphology and concentration of the etchant, the angle in slanted SiNWs, kink position in kinked SiNWs, and aspect ratio of straight SiNWs can be controlled judiciously, leading to enhanced optical absorption in the broadband solar spectrum.
Collapse
Affiliation(s)
- T K Adhila
- Nanomaterials Research Laboratory, Surface Engineering Division, CSIR-National Aerospace Laboratories, Kodihalli, Bangalore 560 017, India
- Academy of Scientific and Innovative Research, CSIR-NAL Campus, Kodihalli, Bangalore 560 017, India
| | - Hemaprabha Elangovan
- Department of Materials Engineering, Indian Institute of Science, CV Raman Road, Bangalore 560 012, India
| | - Siju John
- Nanomaterials Research Laboratory, Surface Engineering Division, CSIR-National Aerospace Laboratories, Kodihalli, Bangalore 560 017, India
| | - Kamanio Chattopadhyay
- Department of Materials Engineering, Indian Institute of Science, CV Raman Road, Bangalore 560 012, India
| | - Harish C Barshilia
- Nanomaterials Research Laboratory, Surface Engineering Division, CSIR-National Aerospace Laboratories, Kodihalli, Bangalore 560 017, India
| |
Collapse
|
13
|
Kim TK, Bae JH, Kim J, Cho MK, Kim YC, Jin S, Chun D. Curved Structure of Si by Improving Etching Direction Controllability in Magnetically Guided Metal-Assisted Chemical Etching. MICROMACHINES 2020; 11:mi11080744. [PMID: 32751667 PMCID: PMC7463845 DOI: 10.3390/mi11080744] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 07/23/2020] [Accepted: 07/27/2020] [Indexed: 11/16/2022]
Abstract
Metal-assisted chemical etching (MACE) is widely used to fabricate micro-/nano-structured Si owing to its simplicity and cost-effectiveness. The technique of magnetically guided MACE, involving MACE with a tri-layer metal catalyst, was developed to improve etching speed as well as to adjust the etching direction using an external magnetic field. However, the controllability of the etching direction diminishes with an increase in the etching dimension, owing to the corrosion of Fe due to the etching solution; this impedes the wider application of this approach for the fabrication of complex micro Si structures. In this study, we modified a tri-layer metal catalyst (Au/Fe/Au), wherein the Fe layer was encapsulated to improve direction controllability; this improved controllability was achieved by protecting Fe against the corrosion caused by the etching solution. We demonstrated curved Si microgroove arrays via magnetically guided MACE with Fe encapsulated in the tri-layer catalyst. Furthermore, the curvature in the curved Si microarrays could be modulated via an external magnetic field, indicating that direction controllability could be maintained even for the magnetically guided MACE of bulk Si. The proposed fabrication method developed for producing curved Si microgroove arrays can be applied to electronic devices and micro-electromechanical systems.
Collapse
Affiliation(s)
- Tae Kyoung Kim
- Materials Science and Engineering, University of California at San Diego, 9500 Gilman Dr, La Jolla, CA 92093, USA; (T.K.K.); (S.J.)
| | - Jee-Hwan Bae
- Advanced Analysis Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; (J.-H.B.); (J.K.); (M.K.C.)
| | - Juyoung Kim
- Advanced Analysis Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; (J.-H.B.); (J.K.); (M.K.C.)
| | - Min Kyung Cho
- Advanced Analysis Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; (J.-H.B.); (J.K.); (M.K.C.)
| | - Yu-Chan Kim
- Center for Biomaterials, Biomedical Research Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea;
| | - Sungho Jin
- Materials Science and Engineering, University of California at San Diego, 9500 Gilman Dr, La Jolla, CA 92093, USA; (T.K.K.); (S.J.)
| | - Dongwon Chun
- Advanced Analysis Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea; (J.-H.B.); (J.K.); (M.K.C.)
- Correspondence:
| |
Collapse
|
14
|
Romano L, Stampanoni M. Microfabrication of X-ray Optics by Metal Assisted Chemical Etching: A Review. MICROMACHINES 2020; 11:E589. [PMID: 32545633 PMCID: PMC7344591 DOI: 10.3390/mi11060589] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/08/2020] [Accepted: 06/10/2020] [Indexed: 11/19/2022]
Abstract
High-aspect-ratio silicon micro- and nanostructures are technologically relevant in several applications, such as microelectronics, microelectromechanical systems, sensors, thermoelectric materials, battery anodes, solar cells, photonic devices, and X-ray optics. Microfabrication is usually achieved by dry-etch with reactive ions and KOH based wet-etch, metal assisted chemical etching (MacEtch) is emerging as a new etching technique that allows huge aspect ratio for feature size in the nanoscale. To date, a specialized review of MacEtch that considers both the fundamentals and X-ray optics applications is missing in the literature. This review aims to provide a comprehensive summary including: (i) fundamental mechanism; (ii) basics and roles to perform uniform etching in direction perpendicular to the <100> Si substrate; (iii) several examples of X-ray optics fabricated by MacEtch such as line gratings, circular gratings array, Fresnel zone plates, and other X-ray lenses; (iv) materials and methods for a full fabrication of absorbing gratings and the application in X-ray grating based interferometry; and (v) future perspectives of X-ray optics fabrication. The review provides researchers and engineers with an extensive and updated understanding of the principles and applications of MacEtch as a new technology for X-ray optics fabrication.
Collapse
Affiliation(s)
- Lucia Romano
- Institute for Biomedical Engineering, ETH Zürich, 8092 Zürich, Switzerland;
- Paul Scherrer Institut, Forschungsstrasse 111, CH-5232 Villigen, Switzerland
- CNR-IMM, Department of Physics, University of Catania, 64 via S. Sofia, 95123 Catania, Italy
| | - Marco Stampanoni
- Institute for Biomedical Engineering, ETH Zürich, 8092 Zürich, Switzerland;
- Paul Scherrer Institut, Forschungsstrasse 111, CH-5232 Villigen, Switzerland
| |
Collapse
|
15
|
Yasuda T, Maeda Y, Matsuzaki K, Okazaki Y, Oda R, Kitada A, Murase K, Fukami K. Spontaneous Symmetry Breaking of Nanoscale Spatiotemporal Pattern as the Origin of Helical Nanopore Etching in Silicon. ACS APPLIED MATERIALS & INTERFACES 2019; 11:48604-48611. [PMID: 31794191 DOI: 10.1021/acsami.9b18025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Nanometric chiral objects such as twisted or helical nanoribbons represent a new class of objects having important potential in a large panel of applications, taking advantage, for example, of electromechanical or optical chirality, local chiral environment for catalysis, and chiral recognition. Supramolecular chemistry has played a central role in the production of such structures through either chiral macromolecules/foldamers or the self-assembly of chiral molecules; the latter can also be used as templates for the sol-gel transcription to silica materials, offering them polymorphisms with further structural stability. Here, we report a totally different and dynamic approach to produce helical mesostructures. This study focuses on helical nanopores that are spontaneously formed in the platinum-assisted chemical etching of silicon by dynamic self-organization under a nonequilibrium state. The symmetry breaking of a helical nanopore formation is achieved by the spatial symmetry breaking of a spatiotemporal pattern at the nanoscale and without incorporation of chiral molecules. Rotational motion of the platinum nanocatalyst, which is regarded as a spatiotemporal pattern at the etching frontier (the platinum/silicon interface), induces precession movement of the nanocatalyst, and movement of the catalyst during etching forms helical nanopores in the silicon. We consider that this study is an important milestone to understand the close relation between spatiotemporal pattern formation and the dynamic emergence of symmetry breaking in chemical reactions.
Collapse
Affiliation(s)
| | | | | | - Yutaka Okazaki
- Institute de Chimie et Biologie des Membranes & des Nanoobjets (UMR5248 CBMN) , CNRS, Université de Bordeaux, Bordeaux INP , 33607 Pessac , France
| | - Reiko Oda
- Institute de Chimie et Biologie des Membranes & des Nanoobjets (UMR5248 CBMN) , CNRS, Université de Bordeaux, Bordeaux INP , 33607 Pessac , France
| | | | | | | |
Collapse
|
16
|
Matsumoto A, Son H, Eguchi M, Iwamoto K, Shimada Y, Furukawa K, Yae S. General corrosion during metal-assisted etching of n-type silicon using different metal catalysts of silver, gold, and platinum. RSC Adv 2019; 10:253-259. [PMID: 35492542 PMCID: PMC9048163 DOI: 10.1039/c9ra08728a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 11/29/2019] [Indexed: 12/04/2022] Open
Abstract
Metal-assisted etching is a promising technique for microfabrication of semiconductors. In this method, porous silicon (Si) can be produced with a very simple procedure, and various nanostructures can be designed by changing the catalyst patterns. The kind of metal catalysts is one of the key factors to control the porous structure. In this work, we performed the etching of n-type Si (100) in a hydrofluoric acid solution containing hydrogen peroxide in the dark using silver, gold, and platinum particles electrolessly deposited at a constant coverage, and demonstrated the difference in the porous structures obtained for the different kind of metal catalysts. By comparing the mass loss of substrates with the depth of pores formed under the metal particles, we found that general corrosion occurred on the top-surface of the Si substrate around the metal particles even under the dark condition. The general corrosion depended on the metal species and it was explained by the formation and dissolution of a mesoporous layer. The kind of metal catalysts influences the dissolution of the Si surface not only under the metal catalysts but also between them. The first report on general corrosion during metal-assisted etching of silicon.![]()
Collapse
Affiliation(s)
- Ayumu Matsumoto
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo 2167 Shosha Himeji Hyogo 671-2280 Japan
| | - Hikoyoshi Son
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo 2167 Shosha Himeji Hyogo 671-2280 Japan
| | - Makiho Eguchi
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo 2167 Shosha Himeji Hyogo 671-2280 Japan
| | - Keishi Iwamoto
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo 2167 Shosha Himeji Hyogo 671-2280 Japan
| | - Yuki Shimada
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo 2167 Shosha Himeji Hyogo 671-2280 Japan
| | - Kyohei Furukawa
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo 2167 Shosha Himeji Hyogo 671-2280 Japan
| | - Shinji Yae
- Department of Chemical Engineering and Materials Science, Graduate School of Engineering, University of Hyogo 2167 Shosha Himeji Hyogo 671-2280 Japan
| |
Collapse
|
17
|
Kim K, Ki B, Choi K, Oh J. Anodic Imprint Lithography: Direct Imprinting of Single Crystalline GaAs with Anodic Stamp. ACS NANO 2019; 13:13465-13473. [PMID: 31593424 DOI: 10.1021/acsnano.9b07072] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Anodic imprint lithography patterns the GaAs substrate electrochemically by applying a voltage through a predefined anodic stamp. This newly devised technique performs anodic etching in a stamping manner. Stamps that serve as anodic electrodes are fabricated precisely, and the patterns can be imprinted continuously on GaAs substrates. The anodic current locally oxidizes the GaAs through the metal attached to the stamp, and the GaAs oxides are subsequently removed by an acid in the solution. The process is simplified because the metal catalyst is not left on the substrate and the use of an oxidizing agent is not required. Anodic imprint lithography integrates the lithography and etching steps without the use of a polymer resist. Predefined anodic stamps with fin, pillar, and mesh arrays clearly imprinted trenches, holes, and embossed disk arrays on the GaAs substrates, respectively. Anodic imprints replace photons and electrons in conventional lithography with electrochemical stamping, which can simplify existing techniques that are highly complex for extreme nanopatterning.
Collapse
Affiliation(s)
- Kyunghwan Kim
- School of Integrated Technology , Yonsei University , 85 Songdogwahak-ro , Yeonsu-gu, Incheon 21983 , Republic of Korea
- Yonsei Institute of Convergence Technology , Yonsei University , 85 Songdogwahak-ro , Yeonsu-gu, Incheon 21983 , Republic of Korea
| | - Bugeun Ki
- School of Integrated Technology , Yonsei University , 85 Songdogwahak-ro , Yeonsu-gu, Incheon 21983 , Republic of Korea
- Yonsei Institute of Convergence Technology , Yonsei University , 85 Songdogwahak-ro , Yeonsu-gu, Incheon 21983 , Republic of Korea
| | - Keorock Choi
- School of Integrated Technology , Yonsei University , 85 Songdogwahak-ro , Yeonsu-gu, Incheon 21983 , Republic of Korea
- Yonsei Institute of Convergence Technology , Yonsei University , 85 Songdogwahak-ro , Yeonsu-gu, Incheon 21983 , Republic of Korea
| | - Jungwoo Oh
- School of Integrated Technology , Yonsei University , 85 Songdogwahak-ro , Yeonsu-gu, Incheon 21983 , Republic of Korea
- Yonsei Institute of Convergence Technology , Yonsei University , 85 Songdogwahak-ro , Yeonsu-gu, Incheon 21983 , Republic of Korea
| |
Collapse
|
18
|
Wang Q, Yuan G, Zhao S, Liu W, Liu Z, Wang J, Li J. Metal-assisted photochemical etching of GaN nanowires: The role of metal distribution. Electrochem commun 2019. [DOI: 10.1016/j.elecom.2019.05.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
|
19
|
Kim JD, Kim M, Kong L, Mohseni PK, Ranganathan S, Pachamuthu J, Chim WK, Chiam SY, Coleman JJ, Li X. Self-Anchored Catalyst Interface Enables Ordered Via Array Formation from Submicrometer to Millimeter Scale for Polycrystalline and Single-Crystalline Silicon. ACS APPLIED MATERIALS & INTERFACES 2018; 10:9116-9122. [PMID: 29406759 DOI: 10.1021/acsami.7b17708] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Defying text definitions of wet etching, metal-assisted chemical etching (MacEtch), a solution-based, damage-free semiconductor etching method, is directional, where the metal catalyst film sinks with the semiconductor etching front, producing 3D semiconductor structures that are complementary to the metal catalyst film pattern. The same recipe that works perfectly to produce ordered array of nanostructures for single-crystalline Si (c-Si) fails completely when applied to polycrystalline Si (poly-Si) with the same doping type and level. Another long-standing challenge for MacEtch is the difficulty of uniformly etching across feature sizes larger than a few micrometers because of the nature of lateral etching. The issue of interface control between the catalyst and the semiconductor in both lateral and vertical directions over time and over distance needs to be systematically addressed. Here, we present a self-anchored catalyst (SAC) MacEtch method, where a nanoporous catalyst film is used to produce nanowires through the pinholes, which in turn physically anchor the catalyst film from detouring as it descends. The systematic vertical etch rate study as a function of porous catalyst diameter from 200 to 900 nm shows that the SAC-MacEtch not only confines the etching direction but also enhances the etch rate due to the increased liquid access path, significantly delaying the onset of the mass-transport-limited critical diameter compared to nonporous catalyst c-Si counterpart. With this enhanced mass transport approach, vias on multistacks of poly-Si/SiO2 are also formed with excellent vertical registry through the polystack, even though they are separated by SiO2 which is readily removed by HF alone with no anisotropy. In addition, 320 μm square through-Si-via (TSV) arrays in 550 μm thick c-Si are realized. The ability of SAC-MacEtch to etch through poly/oxide/poly stack as well as more than half millimeter thick silicon with excellent site specificity for a wide range of feature sizes has significant implications for 2.5D/3D photonic and electronic device applications.
Collapse
Affiliation(s)
- Jeong Dong Kim
- Micro and Nanotechnology Laboratory, Materials Research Laboratory, Department of Electrical and Computer Engineering , University of Illinois at Urbana-Champaign , Urbana , Illinois 61801 , United States
| | - Munho Kim
- Micro and Nanotechnology Laboratory, Materials Research Laboratory, Department of Electrical and Computer Engineering , University of Illinois at Urbana-Champaign , Urbana , Illinois 61801 , United States
| | - Lingyu Kong
- Micro and Nanotechnology Laboratory, Materials Research Laboratory, Department of Electrical and Computer Engineering , University of Illinois at Urbana-Champaign , Urbana , Illinois 61801 , United States
- NUS Graduate School for Integrative Sciences and Engineering , National University of Singapore , 28 Medical Drive , 117456 , Singapore
- Department of Electrical and Computer Engineering , National University of Singapore , 4 Engineering Drive 3 , 117583 , Singapore
- Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, Innovis , 138634 , Singapore
| | - Parsian K Mohseni
- Micro and Nanotechnology Laboratory, Materials Research Laboratory, Department of Electrical and Computer Engineering , University of Illinois at Urbana-Champaign , Urbana , Illinois 61801 , United States
| | | | | | - Wai Kin Chim
- Department of Electrical and Computer Engineering , National University of Singapore , 4 Engineering Drive 3 , 117583 , Singapore
| | - Sing Yang Chiam
- Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, Innovis , 138634 , Singapore
| | - James J Coleman
- Department of Electrical Engineering and Department of Materials Science , University of Texas at Dallas , Richardson , Texas 75080 , United States
| | - Xiuling Li
- Micro and Nanotechnology Laboratory, Materials Research Laboratory, Department of Electrical and Computer Engineering , University of Illinois at Urbana-Champaign , Urbana , Illinois 61801 , United States
- International Institute for Carbon-Neutral Energy Research (I2CNER) , Kyushu University , Fukuoka 819-0395 , Japan
| |
Collapse
|
20
|
Kong L, Song Y, Kim JD, Yu L, Wasserman D, Chim WK, Chiam SY, Li X. Damage-Free Smooth-Sidewall InGaAs Nanopillar Array by Metal-Assisted Chemical Etching. ACS NANO 2017; 11:10193-10205. [PMID: 28880533 DOI: 10.1021/acsnano.7b04752] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Producing densely packed high aspect ratio In0.53Ga0.47As nanostructures without surface damage is critical for beyond Si-CMOS nanoelectronic and optoelectronic devices. However, conventional dry etching methods are known to produce irreversible damage to III-V compound semiconductors because of the inherent high-energy ion-driven process. In this work, we demonstrate the realization of ordered, uniform, array-based In0.53Ga0.47As pillars with diameters as small as 200 nm using the damage-free metal-assisted chemical etching (MacEtch) technology combined with the post-MacEtch digital etching smoothing. The etching mechanism of InxGa1-xAs is explored through the characterization of pillar morphology and porosity as a function of etching condition and indium composition. The etching behavior of In0.53Ga0.47As, in contrast to higher bandgap semiconductors (e.g., Si or GaAs), can be interpreted by a Schottky barrier height model that dictates the etching mechanism constantly in the mass transport limited regime because of the low barrier height. A broader impact of this work relates to the complete elimination of surface roughness or porosity related defects, which can be prevalent byproducts of MacEtch, by post-MacEtch digital etching. Side-by-side comparison of the midgap interface state density and flat-band capacitance hysteresis of both the unprocessed planar and MacEtched pillar In0.53Ga0.47As metal-oxide-semiconductor capacitors further confirms that the surface of the resultant pillars is as smooth and defect-free as before etching. MacEtch combined with digital etching offers a simple, room-temperature, and low-cost method for the formation of high-quality In0.53Ga0.47As nanostructures that will potentially enable large-volume production of In0.53Ga0.47As-based devices including three-dimensional transistors and high-efficiency infrared photodetectors.
Collapse
Affiliation(s)
- Lingyu Kong
- Department of Electrical and Computer Engineering, Micro and Nanotechnology Laboratory, Materials Research Laboratory, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore , 28 Medical Drive, Singapore 117456
- Department of Electrical and Computer Engineering, National University of Singapore , 4 Engineering Drive 3, Singapore 117583
- Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, Innovis, Singapore 138634
| | - Yi Song
- Department of Electrical and Computer Engineering, Micro and Nanotechnology Laboratory, Materials Research Laboratory, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States
| | - Jeong Dong Kim
- Department of Electrical and Computer Engineering, Micro and Nanotechnology Laboratory, Materials Research Laboratory, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States
| | - Lan Yu
- Department of Electrical and Computer Engineering, Micro and Nanotechnology Laboratory, Materials Research Laboratory, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States
| | - Daniel Wasserman
- Department of Electrical and Computer Engineering, Micro and Nanotechnology Laboratory, Materials Research Laboratory, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States
| | - Wai Kin Chim
- Department of Electrical and Computer Engineering, National University of Singapore , 4 Engineering Drive 3, Singapore 117583
| | - Sing Yang Chiam
- Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research) , 2 Fusionopolis Way, Innovis, Singapore 138634
| | - Xiuling Li
- Department of Electrical and Computer Engineering, Micro and Nanotechnology Laboratory, Materials Research Laboratory, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States
- International Institute for Carbon-Neutral Energy Research (I2CNER), Kyushu University , Fukuoka 819-0395, Japan
| |
Collapse
|