Research on Stable, High-Efficiency Amorphous Silicon Multijunction Modules, Semiannual Subcontract Report, 1 January 1990 - 30 June 1991

Technical Report · Sun Dec 01 04:00:00 EST 1991

DOI:https://doi.org/10.2172/5988064· OSTI ID:5988064

Guha, S.

This report describes research to improve the understanding of amorphous silicon alloys and other relevant non-semiconductor materials for use in high-efficiency, large-area multijunction modules. The research produced an average subcell initial efficiency of 8.8% over a 1-ft{sup 2} area using same-band-gap, dual-junction cells deposited over a ZnO/AlSi back reflector. An initial efficiency of 9.6% was achieved using a ZnO/Ag back reflector over smaller substrates. A sputtering machine will be built to deposit a ZnO/Ag back reflector over a 1-ft{sup 2} area so that a higher efficiency can also be obtained on larger substrates. Calculations have been performed to optimize the grid pattern, bus bars, and cell interconnects on modules. With our present state of technology, we expect a difference of about 6% between the aperture-area and active-area efficiencies of modules. Preliminary experiments show a difference of about 8%. We can now predict the performance of single-junction cells after long-term light exposure at 50{degree}C by exposing cells to short-term intense light at different temperatures. We find that single-junction cells deposited on a ZnO/Ag back reflector show the highest stabilized efficiency when the thickness of the intrinsic layers is about 2000 {angstrom}. 8 refs.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• DOE Contract Number: AC36-08GO28308
• OSTI ID: 5988064
• Report Number(s): NREL/TP-214-4453; ON: DE92001197
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
360601 -- Other Materials-- Preparation & Manufacture
360606 -- Other Materials-- Physical Properties-- (1992-)
ALLOYS
ALUMINIUM COMPOUNDS
ALUMINIUM SILICIDES
AMORPHOUS STATE
CHALCOGENIDES
DEPOSITION
DIRECT ENERGY CONVERTERS
DOCUMENT TYPES
EFFICIENCY
ELECTRICAL PROPERTIES
ELEMENTS
EQUIPMENT
METALS
OXIDES
OXYGEN COMPOUNDS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
PROGRESS REPORT
SILICIDES
SILICON ALLOYS
SILICON COMPOUNDS
SILICON SOLAR CELLS
SILVER
SOLAR CELLS
SOLAR EQUIPMENT
TRANSITION ELEMENTS
ZINC COMPOUNDS
ZINC OXIDES
amorphous silicon
high efficiency
multijunction modules
photovoltaics
solar cells