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Title: Amorphous silicon solar cells. Quarterly report No. 2, 1 October 1976 to 31 December 1976

Abstract

Infrared absorption measurements have shown that discharge-produced a-Si contains approx. 16 at. % of bonded hydrogen when deposited near room temperature and that the hydrogen content decreases to approx. 2 at. % for a substrate temperature of approx. 500/sup 0/C. This variation in the concentration of bonded hydrogen appears to be responsible for a reduction in the optical gap as the substrate temperature increases. Improvements in the photoluminescence, the photoconductivity, and the collection efficiency of films after annealing at approx. 200 to 300/sup 0/C indicate that many defects within the gap are being annealed out of the films at these temperatures. The conduction behavior in the field regime of approx. 10/sup 4/ to 10/sup 5/ V/cm appears to be due to the Poole-Frenkel effect. At lower fields the conduction is ohmic and thermally activated, but the pre-exponential term sigma/sub o/ obeys the Meyer-Neldel rule (sigma/sub o/ = sigma/sub oo/exp(E/sub a//kT/sub o/)). Recent experiments with lightly doped, p-type a-Si indicate that this amorphous silicon is a good-quality solar cell material. Pd Schottky-barrier cells without antireflection coatings have shown no degradation after 4400 hours of continuous illumination (approx. 50 to 75 MW/cm/sup 2/).

Authors:
Publication Date:
Research Org.:
RCA Labs., Princeton, NJ (USA)
OSTI Identifier:
6169008
Report Number(s):
DOE/ET/20404-T1; SAN-1286-2; PPPL-77-CR-3
ON: DE81025465
DOE Contract Number:
AC03-76ET20404
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; SILICON; ELECTRICAL PROPERTIES; OPTICAL PROPERTIES; SILICON SOLAR CELLS; AMORPHOUS STATE; ANNEALING; CRYSTAL DEFECTS; EFFICIENCY; ENERGY GAP; HYDROGEN ADDITIONS; INFRARED SPECTRA; P-TYPE CONDUCTORS; PALLADIUM; PHOTOCONDUCTIVITY; PHOTOLUMINESCENCE; QUANTITY RATIO; SCHOTTKY BARRIER SOLAR CELLS; STABILITY; CRYSTAL STRUCTURE; DIRECT ENERGY CONVERTERS; ELECTRIC CONDUCTIVITY; ELEMENTS; EQUIPMENT; HEAT TREATMENTS; LUMINESCENCE; MATERIALS; METALS; PHOTOELECTRIC CELLS; PHOTOVOLTAIC CELLS; PHYSICAL PROPERTIES; PLATINUM METALS; SEMICONDUCTOR MATERIALS; SEMIMETALS; SOLAR CELLS; SOLAR EQUIPMENT; SPECTRA; TRANSITION ELEMENTS; 140501* - Solar Energy Conversion- Photovoltaic Conversion

Citation Formats

Carlson, D.E. Amorphous silicon solar cells. Quarterly report No. 2, 1 October 1976 to 31 December 1976. United States: N. p., 1977. Web. doi:10.2172/6169008.
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Carlson, D.E. Amorphous silicon solar cells. Quarterly report No. 2, 1 October 1976 to 31 December 1976. United States. doi:10.2172/6169008.
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Carlson, D.E. Sat . "Amorphous silicon solar cells. Quarterly report No. 2, 1 October 1976 to 31 December 1976". United States. doi:10.2172/6169008. https://www.osti.gov/servlets/purl/6169008.
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@article{osti_6169008,
title = {Amorphous silicon solar cells. Quarterly report No. 2, 1 October 1976 to 31 December 1976},
author = {Carlson, D.E.},
abstractNote = {Infrared absorption measurements have shown that discharge-produced a-Si contains approx. 16 at. % of bonded hydrogen when deposited near room temperature and that the hydrogen content decreases to approx. 2 at. % for a substrate temperature of approx. 500/sup 0/C. This variation in the concentration of bonded hydrogen appears to be responsible for a reduction in the optical gap as the substrate temperature increases. Improvements in the photoluminescence, the photoconductivity, and the collection efficiency of films after annealing at approx. 200 to 300/sup 0/C indicate that many defects within the gap are being annealed out of the films at these temperatures. The conduction behavior in the field regime of approx. 10/sup 4/ to 10/sup 5/ V/cm appears to be due to the Poole-Frenkel effect. At lower fields the conduction is ohmic and thermally activated, but the pre-exponential term sigma/sub o/ obeys the Meyer-Neldel rule (sigma/sub o/ = sigma/sub oo/exp(E/sub a//kT/sub o/)). Recent experiments with lightly doped, p-type a-Si indicate that this amorphous silicon is a good-quality solar cell material. Pd Schottky-barrier cells without antireflection coatings have shown no degradation after 4400 hours of continuous illumination (approx. 50 to 75 MW/cm/sup 2/).},
doi = {10.2172/6169008},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Jan 01 00:00:00 EST 1977},
month = {Sat Jan 01 00:00:00 EST 1977}
}
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Technical Report:
View Technical Report (1.33 MB)
DOI:  10.2172/6169008
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