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Kolasinski KW. Metal-Assisted Catalytic Etching (MACE) for Nanofabrication of Semiconductor Powders. MICROMACHINES 2021; 12:776. [PMID: 34209231 PMCID: PMC8304928 DOI: 10.3390/mi12070776] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 06/28/2021] [Accepted: 06/29/2021] [Indexed: 12/31/2022]
Abstract
Electroless etching of semiconductors has been elevated to an advanced micromachining process by the addition of a structured metal catalyst. Patterning of the catalyst by lithographic techniques facilitated the patterning of crystalline and polycrystalline wafer substrates. Galvanic deposition of metals on semiconductors has a natural tendency to produce nanoparticles rather than flat uniform films. This characteristic makes possible the etching of wafers and particles with arbitrary shape and size. While it has been widely recognized that spontaneous deposition of metal nanoparticles can be used in connection with etching to porosify wafers, it is also possible to produced nanostructured powders. Metal-assisted catalytic etching (MACE) can be controlled to produce (1) etch track pores with shapes and sizes closely related to the shape and size of the metal nanoparticle, (2) hierarchically porosified substrates exhibiting combinations of large etch track pores and mesopores, and (3) nanowires with either solid or mesoporous cores. This review discussed the mechanisms of porosification, processing advances, and the properties of the etch product with special emphasis on the etching of silicon powders.
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Affiliation(s)
- Kurt W Kolasinski
- Department of Chemistry, West Chester University, West Chester, PA 19383, USA
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2
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Zhang B, Zhang L, Wang H, Wang X. Lessons Learned from the Explosion that Occurred during the Synthesis of Diaminomethanesulfonic Acid: Discussion and Preventative Strategies. ACS CHEMICAL HEALTH & SAFETY 2021. [DOI: 10.1021/acs.chas.1c00021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bo Zhang
- Laboratory of Chemical Biology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China
- Department of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Lei Zhang
- Laboratory of Chemical Biology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China
| | - Hongshuang Wang
- Laboratory of Chemical Biology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China
| | - Xiaohui Wang
- Laboratory of Chemical Biology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, China
- Department of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, China
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Schönekerl S, Acker J. The Role of the Molecular Hydrogen Formation in the Process of Metal-Ion Reduction on Multicrystalline Silicon in a Hydrofluoric Acid Matrix. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:982. [PMID: 33920331 PMCID: PMC8069279 DOI: 10.3390/nano11040982] [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: 03/10/2021] [Revised: 04/08/2021] [Accepted: 04/09/2021] [Indexed: 01/20/2023]
Abstract
Metal deposition on silicon in hydrofluoric acid (HF) solutions is a well-established process for the surface patterning of silicon. The reactions behind this process, especially the formation or the absence of molecular hydrogen (H2), are controversially discussed in the literature. In this study, several batch experiments with Ag+, Cu2+, AuCl4- and PtCl62- in HF matrix and multicrystalline silicon were performed. The stoichiometric amounts of the metal depositions, the silicon dissolution and the molecular hydrogen formation were determined analytically. Based on these data and theoretical considerations of the valence transfer, four reasons for the formation of H2 could be identified. First, H2 is generated in a consecutive reaction after a monovalent hole transfer (h+) to a Si-Si bond. Second, H2 is produced due to a monovalent hole transfer to the Si-H bonds. Third, H2 occurs if Si-Si back bonds of the hydrogen-terminated silicon are attacked by Cu2+ reduction resulting in the intermediate species HSiF3, which is further degraded to H2 and SiF62-. The fourth H2-forming reaction reduces oxonium ions (H3O+) on the silver/, copper/ and gold/silicon contacts via monovalent hole transfer to silicon. In the case of (cumulative) even-numbered valence transfers to silicon, no H2 is produced. The formation of H2 also fails to appear if the equilibrium potential of the 2H3O+/H2 half-cell does not reach the energetic level of the valence bands of the bulk or hydrogen-terminated silicon. Non-hydrogen-forming reactions in silver, copper and gold deposition always occur with at least one H2-forming process. The PtCl62- reduction to Pt proceeds exclusively via even-numbered valence transfers to silicon. This also applies to the reaction of H3O+ at the platinum/silicon contact. Consequently, no H2 is formed during platinum deposition.
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Affiliation(s)
- Stefan Schönekerl
- Department of Physical Chemistry, Faculty of Environment and Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, Universitätsplatz 1, 01968 Senftenberg, Germany;
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Schönekerl S, Acker J. The Kinetics and Stoichiometry of Metal Cation Reduction on Multi-Crystalline Silicon in a Dilute Hydrofluoric Acid Matrix. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E2545. [PMID: 33348864 PMCID: PMC7766330 DOI: 10.3390/nano10122545] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/11/2020] [Accepted: 12/13/2020] [Indexed: 11/16/2022]
Abstract
In this study, the process of metal cation reduction on multi-crystalline silicon in a dilute hydrofluoric acid (HF) matrix is described using Ag(I), Cu(II), Au(III) and Pt(IV). The experimental basis utilized batch tests with various solutions of different metal cation and HF concentrations and multi-crystalline silicon wafers. The metal deposition kinetics and the stoichiometry of metal deposition and silicon dissolution were calculated by means of consecutive sampling and analysis of the solutions. Several reaction mechanisms and reaction steps of the process were discussed by overlaying the results with theoretical considerations. It was deduced that the metal deposition was fastest if the holes formed during metal ion reduction could be transferred to the valence bands of the bulk and surface silicon with hydrogen termination. By contrast, the kinetics were lowest when the redox levels of the metal ion/metal half-cells were weak and the equilibrium potential of the H3O+/H2 half-cells was high. Further minima were identified at the thresholds where H3O+ reduction was inhibited, the valence transfer via valence band mechanism was limited by a Schottky barrier and the dissolution of oxidized silicon was restricted by the activity of the HF species F-, HF2- and H2F3-. The findings of the stoichiometric conditions provided further indications of the involvement of H3O+ and H2O as oxidizing agents in addition to metal ions, and the hydrogen of the surface silicon termination as a reducing agent in addition to the silicon. The H3O+ reduction is the predominant process in dilute metal ion solutions unless it is disabled due to the metal-dependent equilibrium potential of the H3O+/H2 half-cell and the energetic level of the valence bands of the silicon. As silicon is not oxidized up to the oxidation state +IV by the reduction of the metal ions and H3O+, water is suspected of acting as a secondary oxidant. The stoichiometric ratios increased up to a maximum with higher molalities of the metal ions, in the manner of a sigmoidal function. If, owing to the redox level of the metal half-cells and the energetic level of the valence band at the metal-silicon contact, the surface silicon can be oxidized, the hydrogen of the termination is the further reducing agent.
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Affiliation(s)
- Stefan Schönekerl
- Department of Physical Chemistry, Faculty of Environment and Natural Sciences, Brandenburg University of Technology Cottbus-Senftenberg, Universitätsplatz 1, 01968 Senftenberg, Germany;
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Wang Z, Bi Y. Boosting the Dynamic Range for Electrochemical Sensing of Hydrogen Peroxide by Enhanced Integration of Pd Nanoparticles in 3D Porous Si Framework. ELECTROANAL 2020. [DOI: 10.1002/elan.202060233] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Zi Wang
- National Key Laboratory of Science and Technology on Micro/Nano Fabrication Shanghai Jiao Tong University Shanghai 200240 China
| | - Yunke Bi
- Department of Neurosurgery Shanghai First People's Hospital School of Medicine Shanghai Jiao Tong University Shanghai 201620 China
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Tamarov K, Kiviluoto R, Swanson JD, Unger BA, Ernst AT, Aindow M, Riikonen J, Lehto VP, Kolasinski KW. Low-Load Metal-Assisted Catalytic Etching Produces Scalable Porosity in Si Powders. ACS APPLIED MATERIALS & INTERFACES 2020; 12:48969-48981. [PMID: 33052667 DOI: 10.1021/acsami.0c13980] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The recently discovered low-load metal-assisted catalytic etching (LL-MACE) creates nanostructured Si with controllable and variable characteristics that distinguish this technique from the conventional high-load variant. LL-MACE employs 150 times less metal catalyst and produces porous Si instead of Si nanowires. In this work, we demonstrate that some of the features of LL-MACE cannot be explained by the present understanding of MACE. With mechanistic insight derived from extensive experimentation, it is demonstrated that (1) the method allows the use of not only Ag, Pd, Pt, and Au as metal catalysts but also Cu and (2) judicious combinations of process parameters such as the type of metal, Si doping levels, and etching temperatures facilitate control over yield (0.065-88%), pore size (3-100 nm), specific surface area (20-310 m2·g-1), and specific pore volume (0.05-1.05 cm3·g-1). The porous structure of the product depends on the space-charge layer, which is controlled by the Si doping and the chemical identity of the deposited metal. The porous structure was also dependent on the dynamic structure of the deposited metal. A distinctive comet-like structure of metal nanoparticles was observed after etching with Cu, Ag, Pd, and, in some cases, Pt; this structure consisted of 10-50 nm main particles surrounded by smaller (<5 nm) nanoparticles. With good scalability and precise control of structural properties, LL-MACE facilitates Si applications in photovoltaics, energy storage, biomedicine, and water purification.
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Affiliation(s)
- Konstantin Tamarov
- Department of Applied Physics, University of Eastern Finland, 70210 Kuopio, Finland
| | - Riku Kiviluoto
- Department of Applied Physics, University of Eastern Finland, 70210 Kuopio, Finland
| | - Joseph D Swanson
- Department of Chemistry, West Chester University, West Chester, Pennsylvania 19383-2115, United States
| | - Bret A Unger
- Department of Chemistry, West Chester University, West Chester, Pennsylvania 19383-2115, United States
| | - Alexis T Ernst
- Department of Materials Science and Engineering, Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269-3136, United States
| | - Mark Aindow
- Department of Materials Science and Engineering, Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269-3136, United States
| | - Joakim Riikonen
- Department of Applied Physics, University of Eastern Finland, 70210 Kuopio, Finland
| | - Vesa-Pekka Lehto
- Department of Applied Physics, University of Eastern Finland, 70210 Kuopio, Finland
| | - Kurt W Kolasinski
- Department of Chemistry, West Chester University, West Chester, Pennsylvania 19383-2115, United States
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Tamarov K, Swanson JD, Unger BA, Kolasinski KW, Ernst AT, Aindow M, Lehto VP, Riikonen J. Controlling the Nature of Etched Si Nanostructures: High- versus Low-Load Metal-Assisted Catalytic Etching (MACE) of Si Powders. ACS APPLIED MATERIALS & INTERFACES 2020; 12:4787-4796. [PMID: 31888334 DOI: 10.1021/acsami.9b20514] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Metal-assisted catalytic etching (MACE) involving Ag deposited on Si particles has been reported as a facile method for the production of Si nanowires (Si NWs). We show that the structure of Si particles subjected to MACE changes dramatically in response to changing the loading of the Ag catalyst. The use of acetic acid as a surfactant and controlled injection of AgNO3(aq) enhanced Ag deposition. The use of acetic acid and controlled injection of H2O2 not only facilitated optimization of the etching step but also allowed us to identify a previously unobserved etching regime that we denote as low-load MACE (LL-MACE). Material produced by LL-MACE exhibits dramatically different yield and structural characteristics as compared to conventionally produced material. We demonstrate the production of Si NWs as well as mesoporous Si nanoparticles from an inexpensive metallurgical-grade Si powder. High loading of Ag (HL-MACE) generates parallel etch track pores created by the correlated motion of Ag nanoparticles. The uniform size distribution (predominantly 70-100 nm) of the Ag nanoparticles is generated dynamically during etching. The walls of these etch track pores are cleaved readily by ultrasonic agitation to form Si NWs. Low loading of Ag (LL-MACE) creates 10-50 nm Ag nanoparticles that etch in an uncorrelated (randomly directed) fashion to generate a bimodal distribution of mesoporosity peaking at ∼4 and 13-21 nm. The use of a syringe pump to deliver the oxidant (H2O2) and Ag+ is essential for increased product uniformity and yield. Different process temperatures and grades of Si produced significantly different pore size distributions. These results facilitate the production of Si NWs and mesoporous nanoparticles with high yield, low cost, and controlled properties that are suitable for applications in, e.g., lithium-ion batteries, drug delivery, as well as biomedical imaging and contrast enhancement.
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Affiliation(s)
- Konstantin Tamarov
- Department of Applied Physics , University of Eastern Finland , Kuopio FI-70211 , Finland
| | - Joseph D Swanson
- Department of Chemistry , West Chester University , West Chester , Pennsylvania 19383 , United States
| | - Bret A Unger
- Department of Chemistry , West Chester University , West Chester , Pennsylvania 19383 , United States
| | - Kurt W Kolasinski
- Department of Chemistry , West Chester University , West Chester , Pennsylvania 19383 , United States
| | - Alexis T Ernst
- Department of Materials Science and Engineering, Institute of Materials Science , University of Connecticut , Storrs , Connecticut 06269 , United States
| | - Mark Aindow
- Department of Materials Science and Engineering, Institute of Materials Science , University of Connecticut , Storrs , Connecticut 06269 , United States
| | - Vesa-Pekka Lehto
- Department of Applied Physics , University of Eastern Finland , Kuopio FI-70211 , Finland
| | - Joakim Riikonen
- Department of Applied Physics , University of Eastern Finland , Kuopio FI-70211 , Finland
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Venkatasubramanian A, Sauer VTK, Westwood-Bachman JN, Cui K, Xia M, Wishart DS, Hiebert WK. Porous Nanophotonic Optomechanical Beams for Enhanced Mass Adsorption. ACS Sens 2019; 4:1197-1202. [PMID: 30942578 DOI: 10.1021/acssensors.8b01366] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We have developed a porous silicon nanocantilever for a nano-optomechanical system (NOMS) with a universal sensing surface for enhanced sensitivity. Using electron beam lithography, we selectively applied a V2O5/HF stain etch to the mechanical elements while protecting the silicon-on-insulator photonic ring resonators. This simple, rapid, and electrodeless approach generates tunable device porosity simultaneously with the mechanical release step. By controlling the porous etchant concentration and etch time, the porous etch depth, resonant frequency, and the adsorption surface area could be precisely manipulated. Using this control, cantilever sensors ranging from nonporous to fully porous were fabricated and tested as gas-phase mass sensors of volatile organic compounds coming from a gas chromatography stream. The fully porous cantilever produced a dramatic 10-fold increase in sensing signal and a 6-fold improvement in limit of detection (LOD) compared to an otherwise identical nonporous cantilever. This signal improvement could be separated into mass responsivity increase and adsorption increase components. Allan deviation measurements indicate that a further 4-fold improvement in LOD could be expected upon speeding up characteristic peak response time from 1 s to 50 ms. These results show promise for performance enhancement in nanomechanical sensors for applications in gas sensing, gas chromatography, and mass spectrometry.
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Affiliation(s)
- Anandram Venkatasubramanian
- Nanotechnology Research Centre, National Research Council of Canada, Edmonton, Alberta T6G 2M9, Canada
- Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2R3, Canada
| | - Vincent T. K. Sauer
- Nanotechnology Research Centre, National Research Council of Canada, Edmonton, Alberta T6G 2M9, Canada
- Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2R3, Canada
| | - Jocelyn N. Westwood-Bachman
- Nanotechnology Research Centre, National Research Council of Canada, Edmonton, Alberta T6G 2M9, Canada
- Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Kai Cui
- Nanotechnology Research Centre, National Research Council of Canada, Edmonton, Alberta T6G 2M9, Canada
| | - Mike Xia
- Nanotechnology Research Centre, National Research Council of Canada, Edmonton, Alberta T6G 2M9, Canada
| | - David S. Wishart
- Nanotechnology Research Centre, National Research Council of Canada, Edmonton, Alberta T6G 2M9, Canada
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2R3, Canada
- Department of Computing Science, University of Alberta, Edmonton, Alberta T6G 2E8, Canada
| | - Wayne K. Hiebert
- Nanotechnology Research Centre, National Research Council of Canada, Edmonton, Alberta T6G 2M9, Canada
- Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
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Kolasinski KW, Gimbar NJ, Yu H, Aindow M, Mäkilä E, Salonen J. Regenerative Electroless Etching of Silicon. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201610162] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Kurt W. Kolasinski
- Department of Chemistry; West Chester University; West Chester PA 19383-2115 USA
| | - Nathan J. Gimbar
- Department of Chemistry; West Chester University; West Chester PA 19383-2115 USA
| | - Haibo Yu
- Department of Materials Science & Engineering, Institute of Materials Science; University of Connecticut, Storrs; CT 06269-3136 USA
| | - Mark Aindow
- Department of Materials Science & Engineering, Institute of Materials Science; University of Connecticut, Storrs; CT 06269-3136 USA
| | - Ermei Mäkilä
- Department of Physics and Astronomy; University of Turku; 20014 Turku Finland
| | - Jarno Salonen
- Department of Physics and Astronomy; University of Turku; 20014 Turku Finland
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Kolasinski KW, Gimbar NJ, Yu H, Aindow M, Mäkilä E, Salonen J. Regenerative Electroless Etching of Silicon. Angew Chem Int Ed Engl 2016; 56:624-627. [PMID: 27925365 DOI: 10.1002/anie.201610162] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 11/07/2016] [Indexed: 11/06/2022]
Abstract
Regenerative electroless etching (ReEtching), described herein for the first time, is a method of producing nanostructured semiconductors in which an oxidant (Ox1 ) is used as a catalytic agent to facilitate the reaction between a semiconductor and a second oxidant (Ox2 ) that would be unreactive in the primary reaction. Ox2 is used to regenerate Ox1 , which is capable of initiating etching by injecting holes into the semiconductor valence band. Therefore, the extent of reaction is controlled by the amount of Ox2 added, and the rate of reaction is controlled by the injection rate of Ox2 . This general strategy is demonstrated specifically for the production of highly luminescent, nanocrystalline porous Si from the reaction of V2 O5 in HF(aq) as Ox1 and H2 O2 (aq) as Ox2 with Si powder and wafers.
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Affiliation(s)
- Kurt W Kolasinski
- Department of Chemistry, West Chester University, West Chester, PA, 19383-2115, USA
| | - Nathan J Gimbar
- Department of Chemistry, West Chester University, West Chester, PA, 19383-2115, USA
| | - Haibo Yu
- Department of Materials Science & Engineering, Institute of Materials Science, University of Connecticut, Storrs, CT, 06269-3136, USA
| | - Mark Aindow
- Department of Materials Science & Engineering, Institute of Materials Science, University of Connecticut, Storrs, CT, 06269-3136, USA
| | - Ermei Mäkilä
- Department of Physics and Astronomy, University of Turku, 20014, Turku, Finland
| | - Jarno Salonen
- Department of Physics and Astronomy, University of Turku, 20014, Turku, Finland
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Kolasinski KW, Barclay WB, Sun Y, Aindow M. The stoichiometry of metal assisted etching (MAE) of Si in V2O5+HF and HOOH+HF solutions. Electrochim Acta 2015. [DOI: 10.1016/j.electacta.2015.01.162] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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12
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Ayat M, Belhousse S, Boarino L, Gabouze N, Boukherroub R, Kechouane M. Formation of nanostructured silicon surfaces by stain etching. NANOSCALE RESEARCH LETTERS 2014; 9:482. [PMID: 25435830 PMCID: PMC4242786 DOI: 10.1186/1556-276x-9-482] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 08/26/2014] [Indexed: 06/04/2023]
Abstract
In this work, we report the fabrication of ordered silicon structures by chemical etching of silicon in vanadium oxide (V2O5)/hydrofluoric acid (HF) solution. The effects of the different etching parameters including the solution concentration, temperature, and the presence of metal catalyst film deposition (Pd) on the morphologies and reflective properties of the etched Si surfaces were studied. Scanning electron microscopy (SEM) was carried out to explore the morphologies of the etched surfaces with and without the presence of catalyst. In this case, the attack on the surfaces with a palladium deposit begins by creating uniform circular pores on silicon in which we distinguish the formation of pyramidal structures of silicon. Fourier transform infrared spectroscopy (FTIR) demonstrates that the surfaces are H-terminated. A UV-Vis-NIR spectrophotometer was used to study the reflectance of the structures obtained. A reflectance of 2.21% from the etched Si surfaces in the wavelength range of 400 to 1,000 nm was obtained after 120 min of etching while it is of 4.33% from the Pd/Si surfaces etched for 15 min.
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Affiliation(s)
- Maha Ayat
- Centre de Recherche en Technologie des Semi-conducteurs pour l'Energétique (CRTSE), Thin Films, Surface and Interface Division, 02, Bd. Dr. Frantz Fanon, B.P. 140, Alger-7 Merveilles, 16038 Algiers, Algeria
- Université des Sciences et Technologies Houari Boumediene (USTHB), B.P. 32, El Alia, Bab Ezzouar, 16111 Algiers, Algeria
| | - Samia Belhousse
- Centre de Recherche en Technologie des Semi-conducteurs pour l'Energétique (CRTSE), Thin Films, Surface and Interface Division, 02, Bd. Dr. Frantz Fanon, B.P. 140, Alger-7 Merveilles, 16038 Algiers, Algeria
| | - Luca Boarino
- NanoFacility, Instituto Nazionale di Ricerca Metrologica, Strada delle Cacce 91, Torino 10135, Italy
| | - Noureddine Gabouze
- Centre de Recherche en Technologie des Semi-conducteurs pour l'Energétique (CRTSE), Thin Films, Surface and Interface Division, 02, Bd. Dr. Frantz Fanon, B.P. 140, Alger-7 Merveilles, 16038 Algiers, Algeria
| | - Rabah Boukherroub
- Interdisciplinary Research Institute (IRI), IRI-IEMN, Avenue Poincaré, B.P. 69, 59652 Villeneuve-d'Ascq, France
| | - Mohamed Kechouane
- Université des Sciences et Technologies Houari Boumediene (USTHB), B.P. 32, El Alia, Bab Ezzouar, 16111 Algiers, Algeria
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Li X, Xiao Y, Yan C, Zhou K, Miclea PT, Meyer S, Schweizer SL, Sprafke A, Lee JH, Wehrspohn RB. Self-purification model for metal-assisted chemical etching of metallurgical silicon. Electrochim Acta 2014. [DOI: 10.1016/j.electacta.2014.05.048] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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14
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Kolasinski KW. The mechanism of galvanic/metal-assisted etching of silicon. NANOSCALE RESEARCH LETTERS 2014; 9:432. [PMID: 25221459 PMCID: PMC4149979 DOI: 10.1186/1556-276x-9-432] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 07/29/2014] [Indexed: 05/04/2023]
Abstract
Metal-assisted etching is initiated by hole injection from an oxidant catalyzed by a metal nanoparticle or film on a Si surface. It is shown that the electronic structure of the metal/Si interface, i.e., band bending, is not conducive to diffusion of the injected hole away from the metal in the case of Ag or away from the metal/Si interface in the cases of Au, Pd, and Pt. Since holes do not diffuse away from the metals, the electric field resulting from charging of the metal after hole injection must instead be the cause of metal-assisted etching.
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Affiliation(s)
- Kurt W Kolasinski
- Department of Chemistry, West Chester University, West Chester, PA 19383-2115, USA
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Kolasinski KW. The Mechanism of Photohydrosilylation on Silicon and Porous Silicon Surfaces. J Am Chem Soc 2013; 135:11408-12. [PMID: 23837552 DOI: 10.1021/ja406063n] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Kurt W. Kolasinski
- Department of Chemistry, West Chester University, West Chester, Pennsylvania 19383, United
States
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