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Title: Vertically aligned crystalline silicon nanowires with controlled diameters for energy conversion applications: Experimental and theoretical insights

Abstract

Vertically orientated single crystalline silicon nanowire (SiNW) arrays with controlled diameters are fabricated via a metal-assisted chemical etching method. The diameter of the fabricated nanowires is controlled by simply varying the etching time in HF/H{sub 2}O{sub 2} electrolytes. The fabricated SiNWs have diameters ranging from 117 to 650 nm and lengths from 8 to 18 μm. The optical measurements showed a significant difference in the reflectance/absorption of the SiNWs with different diameters, where the reflectance increases with increasing the diameter of the SiNWs. The SiNWs showed significant photoluminescence (PL) emission spectra with peaks lying between 380 and 670 nm. The PL intensity increases as the diameter increases and shows red shift for peaks at ∼670 nm. The increase or decrease of reflectivity is coincident with PL intensity at wavelength ∼660 nm. The x-ray diffraction patterns confirm the high crystallinity of the fabricated SiNWs. In addition, the Raman spectra showed a shift in the first order transverse band toward lower frequencies compared to that usually seen for c-Si. Finite difference time domain simulations have been performed to confirm the effect of change of diameter on the optical properties of the nanowires. The simulation results showed good agreement with the experimental results for the SiNWs of differentmore » diameters.« less

Authors:
;
Publication Date:
OSTI Identifier:
22275522
Resource Type:
Journal Article
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 115; Journal Issue: 19; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; ABSORPTION; COMPARATIVE EVALUATIONS; EMISSION SPECTRA; ENERGY CONVERSION; ETCHING; HYDROFLUORIC ACID; HYDROGEN PEROXIDE; MONOCRYSTALS; PHOTOLUMINESCENCE; QUANTUM WIRES; RAMAN SPECTRA; REFLECTIVITY; SILICON; X-RAY DIFFRACTION

Citation Formats

Razek, Sara Abdel, Swillam, Mohamed A., and Allam, Nageh K., E-mail: nageh.allam@aucegypt.edu. Vertically aligned crystalline silicon nanowires with controlled diameters for energy conversion applications: Experimental and theoretical insights. United States: N. p., 2014. Web. doi:10.1063/1.4876477.
Razek, Sara Abdel, Swillam, Mohamed A., & Allam, Nageh K., E-mail: nageh.allam@aucegypt.edu. Vertically aligned crystalline silicon nanowires with controlled diameters for energy conversion applications: Experimental and theoretical insights. United States. https://doi.org/10.1063/1.4876477
Razek, Sara Abdel, Swillam, Mohamed A., and Allam, Nageh K., E-mail: nageh.allam@aucegypt.edu. 2014. "Vertically aligned crystalline silicon nanowires with controlled diameters for energy conversion applications: Experimental and theoretical insights". United States. https://doi.org/10.1063/1.4876477.
@article{osti_22275522,
title = {Vertically aligned crystalline silicon nanowires with controlled diameters for energy conversion applications: Experimental and theoretical insights},
author = {Razek, Sara Abdel and Swillam, Mohamed A. and Allam, Nageh K., E-mail: nageh.allam@aucegypt.edu},
abstractNote = {Vertically orientated single crystalline silicon nanowire (SiNW) arrays with controlled diameters are fabricated via a metal-assisted chemical etching method. The diameter of the fabricated nanowires is controlled by simply varying the etching time in HF/H{sub 2}O{sub 2} electrolytes. The fabricated SiNWs have diameters ranging from 117 to 650 nm and lengths from 8 to 18 μm. The optical measurements showed a significant difference in the reflectance/absorption of the SiNWs with different diameters, where the reflectance increases with increasing the diameter of the SiNWs. The SiNWs showed significant photoluminescence (PL) emission spectra with peaks lying between 380 and 670 nm. The PL intensity increases as the diameter increases and shows red shift for peaks at ∼670 nm. The increase or decrease of reflectivity is coincident with PL intensity at wavelength ∼660 nm. The x-ray diffraction patterns confirm the high crystallinity of the fabricated SiNWs. In addition, the Raman spectra showed a shift in the first order transverse band toward lower frequencies compared to that usually seen for c-Si. Finite difference time domain simulations have been performed to confirm the effect of change of diameter on the optical properties of the nanowires. The simulation results showed good agreement with the experimental results for the SiNWs of different diameters.},
doi = {10.1063/1.4876477},
url = {https://www.osti.gov/biblio/22275522}, journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 19,
volume = 115,
place = {United States},
year = {Wed May 21 00:00:00 EDT 2014},
month = {Wed May 21 00:00:00 EDT 2014}
}