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Title: Use of Optical Microscopy to Examine Crystallite Nucleation and Growth in Thermally Annealed Plasma Enhanced Chemical Vapor Deposition and Hot Wire Chemical Vapor Deposition a-Si:H Films

Abstract

We report a simple method to investigate crystallite nucleation and growth in stepwise, thermally annealed plasma enhanced chemical vapor deposition and hot wire chemical vapor deposition a-Si:H films. By confining film thicknesses to the range 500-4000 {angstrom}, optical microscopy in the reflection mode can be used to readily detect crystallites in the thermally annealed a-Si:H lattice. Measurements of the crystallite density versus annealing time for identically prepared films of different thickness show that the crystallite nucleation rate is smaller for thinner films, suggesting that crystallite nucleation is homogeneous, in agreement with previous results. A comparison of film nucleation rates with those obtained by other methods on identically prepared films shows excellent agreement, thus establishing the validity of the current technique. The potential effect of impurity (oxygen) incorporation during the stepwise annealing in air is shown not to affect crystallite nucleation and growth, in that SIMS oxygen profiles for stepwise versus continuous annealing show not only similar impurity profiles but also similar bulk impurity densities.

Authors:
; ; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
OSTI Identifier:
1048996
Report Number(s):
NREL/JA-5200-55677
Journal ID: ISSN 0021-8979; JAPIAU; TRN: US201217%%267
DOE Contract Number:  
AC36-08GO28308
Resource Type:
Journal Article
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 111; Journal Issue: 10; Related Information: Article No. 103501; Journal ID: ISSN 0021-8979
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; 42 ENGINEERING; AIR; ANNEALING; CHEMICAL VAPOR DEPOSITION; NUCLEATION; OPTICAL MICROSCOPY; OXYGEN; PLASMA; REFLECTION; THICKNESS; nucleation; grain growth; transmission electron microscopy

Citation Formats

Mahan, A. H., Dabney, Matthew S., Reedy, Jr., Robert C., Molina, Daniela, and Ginley, David S. Use of Optical Microscopy to Examine Crystallite Nucleation and Growth in Thermally Annealed Plasma Enhanced Chemical Vapor Deposition and Hot Wire Chemical Vapor Deposition a-Si:H Films. United States: N. p., 2012. Web. doi:10.1063/1.4712045.
Mahan, A. H., Dabney, Matthew S., Reedy, Jr., Robert C., Molina, Daniela, & Ginley, David S. Use of Optical Microscopy to Examine Crystallite Nucleation and Growth in Thermally Annealed Plasma Enhanced Chemical Vapor Deposition and Hot Wire Chemical Vapor Deposition a-Si:H Films. United States. https://doi.org/10.1063/1.4712045
Mahan, A. H., Dabney, Matthew S., Reedy, Jr., Robert C., Molina, Daniela, and Ginley, David S. Tue . "Use of Optical Microscopy to Examine Crystallite Nucleation and Growth in Thermally Annealed Plasma Enhanced Chemical Vapor Deposition and Hot Wire Chemical Vapor Deposition a-Si:H Films". United States. https://doi.org/10.1063/1.4712045.
@article{osti_1048996,
title = {Use of Optical Microscopy to Examine Crystallite Nucleation and Growth in Thermally Annealed Plasma Enhanced Chemical Vapor Deposition and Hot Wire Chemical Vapor Deposition a-Si:H Films},
author = {Mahan, A. H. and Dabney, Matthew S. and Reedy, Jr., Robert C. and Molina, Daniela and Ginley, David S.},
abstractNote = {We report a simple method to investigate crystallite nucleation and growth in stepwise, thermally annealed plasma enhanced chemical vapor deposition and hot wire chemical vapor deposition a-Si:H films. By confining film thicknesses to the range 500-4000 {angstrom}, optical microscopy in the reflection mode can be used to readily detect crystallites in the thermally annealed a-Si:H lattice. Measurements of the crystallite density versus annealing time for identically prepared films of different thickness show that the crystallite nucleation rate is smaller for thinner films, suggesting that crystallite nucleation is homogeneous, in agreement with previous results. A comparison of film nucleation rates with those obtained by other methods on identically prepared films shows excellent agreement, thus establishing the validity of the current technique. The potential effect of impurity (oxygen) incorporation during the stepwise annealing in air is shown not to affect crystallite nucleation and growth, in that SIMS oxygen profiles for stepwise versus continuous annealing show not only similar impurity profiles but also similar bulk impurity densities.},
doi = {10.1063/1.4712045},
url = {https://www.osti.gov/biblio/1048996}, journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 10,
volume = 111,
place = {United States},
year = {2012},
month = {5}
}

Works referenced in this record:

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Effect of Deposition Temperature on the Crystallization Mechanism of Amorphous Silicon Films on Glass
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P -layer Optimization in High Performance a-Si:H Solar Cells
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