An inverted AlGaAs/GaAs patterned-Ge tunnel junction cascade concentrator solar cell. Final subcontract report, 1 January 1991--31 August 1992
- Research Triangle Inst., Research Triangle Park, NC (United States)
This report describes work to develop inverted-grown Al{sub 0.34}Ga{sub 0.66}As/GaAs cascades. Several significant developments are reported on as follows: (1) The AM1.5 1-sun total-area efficiency of the top Al{sub 0.34}Ga{sub 0.66}As cell for the cascade was improved from 11.3% to 13.2% (NREL measurement [total-area]). (2) The ``cycled`` organometallic vapor phase epitaxy growth (OMVPE) was studied in detail utilizing a combination of characterization techniques including Hall-data, photoluminescence, and secondary ion mass spectroscopy. (3) A technique called eutectic-metal-bonding (EMB) was developed by strain-free mounting of thin GaAs-AlGaAs films (based on lattice-matched growth on Ge substrates and selective plasma etching of Ge substrates) onto Si carrier substrates. Minority-carrier lifetime in an EMB GaAs double-heterostructure was measured as high as 103 nsec, the highest lifetime report for a freestanding GaAs thin film. (4) A thin-film, inverted-grown GaAs cell with a 1-sun AM1.5 active-area efficiency of 20.3% was obtained. This cell was eutectic-metal-bonded onto Si. (5) A thin-film inverted-grown, Al{sub 0.34}Ga{sub 0.66}As/GaAs cascade with AM1.5 efficiency of 19.9% and 21% at 1-sun and 7-suns, respectively, was obtained. This represents an important milestone in the development of an AlGaAs/GaAs cascade by OMVPE utilizing a tunnel interconnect and demonstrates a proof-of-concept for the inverted-growth approach.
- Research Organization:
- National Renewable Energy Lab. (NREL), Golden, CO (United States); Research Triangle Inst., Research Triangle Park, NC (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC02-83CH10093
- OSTI ID:
- 10129182
- Report Number(s):
- NREL/TP-411-5289; ON: DE93000073
- Resource Relation:
- Other Information: PBD: Jan 1993
- Country of Publication:
- United States
- Language:
- English
Similar Records
Development of an IR-transparent, inverted-grown, thin-film, Al[sub 0. 34]Ga[sub 0. 66]As/GaAs cascade solar cell
High Efficiency, Inexpensive Thin Film III-V Photovoltaics using Single-Crystalline-Like, Flexible Substrates
Related Subjects
36 MATERIALS SCIENCE
GALLIUM ARSENIDE SOLAR CELLS
FABRICATION
PROGRESS REPORT
GALLIUM ARSENIDES
SOLAR CONCENTRATORS
SEMICONDUCTOR JUNCTIONS
PHOTOVOLTAIC CONVERSION
EPITAXY
THIN FILMS
BONDING
CHARGE CARRIERS
CARRIER LIFETIME
SILICON
SUBSTRATES
140501
360601
PREPARATION AND MANUFACTURE