skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Recombination and Metastability in Amorphous Silicon and Silicon Germanium Alloys: Annual Subcontract Report, 1 February 1992 - 31 January 1993

Abstract

This report describes work during the second year of a continuing research study. The work is designed to help us understand how recombination, trapping, and band-mobility modification affecting the electronic properties of amorphous semiconductors can be measured, characterized, and described by an appropriate spectrum of defect states. We also worked to determine how light-induced defects in a Si:H and native defects in a-Si:H and native defects in a-Si:H and native defects in a SiGe:H affect transport properties in these materials. During this second year, we continued our experiments on electroluminescence (EL) and transient forward bias current, as well as photocurrent before and after light soaking. We started a program to study thin (0.4{mu}m) p-i-n solar cells, and we studied the effect of optical bias on charge transport in a Si:H films. We performed analytical calculations on a model that predicts an exponential energy region for band tails from dilute random charges. We developed a model for the carrier-recombination-lifetime distribution. We solved the equations for H-diffusion including deep trap levels. Lastly, we analyzed simulation data under forward bias in p-i-n devices. The most interesting and important results were obtained on the EL spectra in thin solar cell devices. We found that,more » at elevated temperatures, thin p-i-n devices displayed primarily defect luminescence (0.8-0.9 eV), while in thick (> 2 {mu}m) devices the luminescence observed was the main band (l.l-1.2 eV). We also found that, in thin cells with buffered layers, p-b-i-n`s the main band luminescence was more pronounced than that in simple p-i-n`s. For the first time we have distinguished between bulk and junction- controlled recombination.« less

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)
OSTI Identifier:
10106395
Report Number(s):
NREL/TP-451-5834
ON: DE94000237; BR: WM1020000
DOE Contract Number:  
AC36-08GO28308
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: Nov 1993
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; SILICON ALLOYS; ELECTRICAL PROPERTIES; GERMANIUM ALLOYS; SILICON SOLAR CELLS; MATERIALS; PROGRESS REPORT; AMORPHOUS STATE; INTERMETALLIC COMPOUNDS; ELECTROLUMINESCENCE; CHARGE CARRIERS; photovoltaics; solar cells; amorphous silicon; silicon germanium; alloys; 140501; 360606; 360602; PHOTOVOLTAIC CONVERSION; PHYSICAL PROPERTIES; STRUCTURE AND PHASE STUDIES

Citation Formats

Silver, M. Recombination and Metastability in Amorphous Silicon and Silicon Germanium Alloys: Annual Subcontract Report, 1 February 1992 - 31 January 1993. United States: N. p., 1993. Web. doi:https://dx.doi.org/10.2172/10106395.
Silver, M. Recombination and Metastability in Amorphous Silicon and Silicon Germanium Alloys: Annual Subcontract Report, 1 February 1992 - 31 January 1993. United States. https://dx.doi.org/10.2172/10106395
Silver, M. Mon . "Recombination and Metastability in Amorphous Silicon and Silicon Germanium Alloys: Annual Subcontract Report, 1 February 1992 - 31 January 1993". United States. https://dx.doi.org/10.2172/10106395. https://www.osti.gov/servlets/purl/10106395.
@article{osti_10106395,
title = {Recombination and Metastability in Amorphous Silicon and Silicon Germanium Alloys: Annual Subcontract Report, 1 February 1992 - 31 January 1993},
author = {Silver, M.},
abstractNote = {This report describes work during the second year of a continuing research study. The work is designed to help us understand how recombination, trapping, and band-mobility modification affecting the electronic properties of amorphous semiconductors can be measured, characterized, and described by an appropriate spectrum of defect states. We also worked to determine how light-induced defects in a Si:H and native defects in a-Si:H and native defects in a-Si:H and native defects in a SiGe:H affect transport properties in these materials. During this second year, we continued our experiments on electroluminescence (EL) and transient forward bias current, as well as photocurrent before and after light soaking. We started a program to study thin (0.4{mu}m) p-i-n solar cells, and we studied the effect of optical bias on charge transport in a Si:H films. We performed analytical calculations on a model that predicts an exponential energy region for band tails from dilute random charges. We developed a model for the carrier-recombination-lifetime distribution. We solved the equations for H-diffusion including deep trap levels. Lastly, we analyzed simulation data under forward bias in p-i-n devices. The most interesting and important results were obtained on the EL spectra in thin solar cell devices. We found that, at elevated temperatures, thin p-i-n devices displayed primarily defect luminescence (0.8-0.9 eV), while in thick (> 2 {mu}m) devices the luminescence observed was the main band (l.l-1.2 eV). We also found that, in thin cells with buffered layers, p-b-i-n`s the main band luminescence was more pronounced than that in simple p-i-n`s. For the first time we have distinguished between bulk and junction- controlled recombination.},
doi = {https://dx.doi.org/10.2172/10106395},
url = {https://www.osti.gov/biblio/10106395}, journal = {},
number = ,
volume = ,
place = {United States},
year = {1993},
month = {11}
}