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Title: Crystallized Silicon Nanostructures - Experimental Characterization and Atomistic Simulations

Abstract

We have synthesized silicon nanocrystalline structures from thermal annealing of thin film amorphous silicon-based multilayers. The annealing procedure that was carried out in vacuum at temperatures up to 1100 °C is integrated in a X-ray diffraction (XRD) setup for real-time monitoring of the formation phases of the nanostructures. The microstructure of the crystallized films is investigated through experimental measurements combined with atomistic simulations of realistic nanocrystalline silicon (nc-Si) models. The multilayers consisting of uniformly alternating thicknesses of hydrogenated amorphous silicon and silicon oxide (SiO2) were deposited by plasma enhanced chemical vapor deposition on crystalline silicon and Corning glass substrates. The crystallized structure consisting of nc-Si structures embedded in an amorphous matrix were further characterized through XRD, Raman spectroscopy, and Fourier transform infrared measurements. We are able to show the different stages of nanostructure formation and how the sizes and the crystallized mass fraction can be controlled in our experimental synthesis. The crystallized silicon structures with large crystalline filling fractions exceeding 50% have been simulated with a robust classical molecular dynamics technique. The crystalline filling fractions and structural order of nc-Si obtained from this simulation are compared with our Raman and XRD measurements.

Authors:
 [1];  [1];  [1];  [2];  [3]
  1. University of West Bohemia
  2. Ames Laboratory
  3. University of Science and Technology of China
Publication Date:
Research Org.:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1163899
Report Number(s):
IS-J 8409
Journal ID: ISSN 0008-4204
DOE Contract Number:
DE-AC02-07CH11358
Resource Type:
Journal Article
Resource Relation:
Journal Name: Canadian Journal of Physics; Journal Volume: 92; Journal Issue: 7/8
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Agbo, Solomon, Sutta, Pavol, Calta, Pavel, Biswas, Rana, and Pan, Bicai. Crystallized Silicon Nanostructures - Experimental Characterization and Atomistic Simulations. United States: N. p., 2014. Web. doi:10.1139/cjp-2013-0442.
Agbo, Solomon, Sutta, Pavol, Calta, Pavel, Biswas, Rana, & Pan, Bicai. Crystallized Silicon Nanostructures - Experimental Characterization and Atomistic Simulations. United States. doi:10.1139/cjp-2013-0442.
Agbo, Solomon, Sutta, Pavol, Calta, Pavel, Biswas, Rana, and Pan, Bicai. Tue . "Crystallized Silicon Nanostructures - Experimental Characterization and Atomistic Simulations". United States. doi:10.1139/cjp-2013-0442.
@article{osti_1163899,
title = {Crystallized Silicon Nanostructures - Experimental Characterization and Atomistic Simulations},
author = {Agbo, Solomon and Sutta, Pavol and Calta, Pavel and Biswas, Rana and Pan, Bicai},
abstractNote = {We have synthesized silicon nanocrystalline structures from thermal annealing of thin film amorphous silicon-based multilayers. The annealing procedure that was carried out in vacuum at temperatures up to 1100 °C is integrated in a X-ray diffraction (XRD) setup for real-time monitoring of the formation phases of the nanostructures. The microstructure of the crystallized films is investigated through experimental measurements combined with atomistic simulations of realistic nanocrystalline silicon (nc-Si) models. The multilayers consisting of uniformly alternating thicknesses of hydrogenated amorphous silicon and silicon oxide (SiO2) were deposited by plasma enhanced chemical vapor deposition on crystalline silicon and Corning glass substrates. The crystallized structure consisting of nc-Si structures embedded in an amorphous matrix were further characterized through XRD, Raman spectroscopy, and Fourier transform infrared measurements. We are able to show the different stages of nanostructure formation and how the sizes and the crystallized mass fraction can be controlled in our experimental synthesis. The crystallized silicon structures with large crystalline filling fractions exceeding 50% have been simulated with a robust classical molecular dynamics technique. The crystalline filling fractions and structural order of nc-Si obtained from this simulation are compared with our Raman and XRD measurements.},
doi = {10.1139/cjp-2013-0442},
journal = {Canadian Journal of Physics},
number = 7/8,
volume = 92,
place = {United States},
year = {Tue Jul 01 00:00:00 EDT 2014},
month = {Tue Jul 01 00:00:00 EDT 2014}
}
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