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Title: Photovoltaic mechanisms in polycrystalline thin film solar cells. Quarterly technical progress report No. 4, July 1-September 30, 1979

Abstract

A more detailed model of the vertical junction effect was generated which investigates both the increase in light generated current due to enhanced collection at the grain boundary and the increase in dark current due to the increased junction area. Results show that there is an overall increase in the cell's maximum power; however, the increase in power is negligible for grain widths exceeding a few tenths of a millimeter. Solar cells were fabricated on a longitudinal section of cast polysilicon which was analyzed crystallographically by means of x-ray diffraction patterns. Special crystallographic orientation relationships are identified for the relative orientations of adjacent grains and for the alignment of their boundary interfaces along certain planar segments. The dark I-V characteristics of the polysilicon cells were dominated by recombination within the space-charge region. Scanning photoresponse patterns are matched with the microstructural information to show, in the absence of any detectable impurity effects, that an insignificant or reduced photoresponse measurement is associated with certain boundaries depending on their structural character. The special orientations of grains are indicated on the basis of a model example to be derived from single or multiple twinning relationships on (111) systems.

Authors:
; ; ;
Publication Date:
Research Org.:
Solarex Corp., Rockville, MD (USA)
OSTI Identifier:
5600780
Report Number(s):
DSE-3413-T3
DOE Contract Number:
ET-78-C-01-3413
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; SILICON SOLAR CELLS; MATHEMATICAL MODELS; PERFORMANCE; EFFICIENCY; ELECTRICAL PROPERTIES; FILMS; GRAIN BOUNDARIES; MICROSTRUCTURE; OPTICAL SCANNERS; ORIENTATION; PHOTOVOLTAIC EFFECT; POLYCRYSTALS; RECOMBINATION; SEMICONDUCTOR JUNCTIONS; SILICON; TWINNING; X-RAY DIFFRACTION; COHERENT SCATTERING; CRYSTAL STRUCTURE; CRYSTALS; DIFFRACTION; DIRECT ENERGY CONVERTERS; ELECTRONIC EQUIPMENT; ELEMENTS; EQUIPMENT; JUNCTIONS; OPTICAL EQUIPMENT; PHOTOELECTRIC CELLS; PHOTOVOLTAIC CELLS; PHYSICAL PROPERTIES; SCATTERING; SEMIMETALS; SOLAR CELLS; SOLAR EQUIPMENT; 140501* - Solar Energy Conversion- Photovoltaic Conversion

Citation Formats

Storti, G., Johnson, S., Lin, H.C., and Armstrong, R.W. Photovoltaic mechanisms in polycrystalline thin film solar cells. Quarterly technical progress report No. 4, July 1-September 30, 1979. United States: N. p., 1979. Web. doi:10.2172/5600780.
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Storti, G., Johnson, S., Lin, H.C., & Armstrong, R.W. Photovoltaic mechanisms in polycrystalline thin film solar cells. Quarterly technical progress report No. 4, July 1-September 30, 1979. United States. doi:10.2172/5600780.
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Storti, G., Johnson, S., Lin, H.C., and Armstrong, R.W. Mon . "Photovoltaic mechanisms in polycrystalline thin film solar cells. Quarterly technical progress report No. 4, July 1-September 30, 1979". United States. doi:10.2172/5600780. https://www.osti.gov/servlets/purl/5600780.
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@article{osti_5600780,
title = {Photovoltaic mechanisms in polycrystalline thin film solar cells. Quarterly technical progress report No. 4, July 1-September 30, 1979},
author = {Storti, G. and Johnson, S. and Lin, H.C. and Armstrong, R.W.},
abstractNote = {A more detailed model of the vertical junction effect was generated which investigates both the increase in light generated current due to enhanced collection at the grain boundary and the increase in dark current due to the increased junction area. Results show that there is an overall increase in the cell's maximum power; however, the increase in power is negligible for grain widths exceeding a few tenths of a millimeter. Solar cells were fabricated on a longitudinal section of cast polysilicon which was analyzed crystallographically by means of x-ray diffraction patterns. Special crystallographic orientation relationships are identified for the relative orientations of adjacent grains and for the alignment of their boundary interfaces along certain planar segments. The dark I-V characteristics of the polysilicon cells were dominated by recombination within the space-charge region. Scanning photoresponse patterns are matched with the microstructural information to show, in the absence of any detectable impurity effects, that an insignificant or reduced photoresponse measurement is associated with certain boundaries depending on their structural character. The special orientations of grains are indicated on the basis of a model example to be derived from single or multiple twinning relationships on (111) systems.},
doi = {10.2172/5600780},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 1979},
month = {Mon Jan 01 00:00:00 EST 1979}
}
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Technical Report:
View Technical Report (6.85 MB)
DOI:  10.2172/5600780
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