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AlGaAs top solar cell for mechanical attachment in a multi-junction tandem concentrator solar cell stackFree-standing, transparent, tunable bandgap AlxGa1-xAs top solar cells have been fabricated for mechanical attachment in a four terminal tandem stack solar cell. Evaluation of the device results has demonstrated 1.80 eV top solar cells with efficiencies of 18 percent (100 X, and AM0) which would yield stack efficiencies of 31 percent (100 X, AM0) with a silicon bottom cell. When fully developed, the AlxGa1-xAs/Si mechanically-stacked two-junction solar cell concentrator system can provide efficiencies of 36 percent (AM0, 100 X). AlxGa1-xAs top solar cells with bandgaps from 1.66 eV to 2.08 eV have been fabricated. Liquid phase epitaxy (LPE) growth techniques have been used and LPE has been found to yield superior AlxGa1-xAs material when compared to molecular beam epitaxy and metal-organic chemical vapor deposition. It is projected that stack assembly technology will be readily applicable to any mechanically stacked multijunction (MSMJ) system. Development of a wide bandgap top solar cell is the only feasible method for obtaining stack efficiencies greater than 40 percent at AM0. System efficiencies of greater than 40 percent can be realized when the AlGaAs top solar cell is used in a three solar cell mechanical stack.
Document ID
Document Type
Conference Paper
Dinetta, L. C. (Astropower, Inc. Newark, DE, United States)
Hannon, M. H. (Astropower, Inc. Newark, DE, United States)
Cummings, J. R. (Astropower, Inc. Newark, DE, United States)
Mcneeley, J. B. (AstroPower, Inc. Newark, DE, United States)
Barnett, Allen M. (Delaware, University Newark, United States)
Date Acquired
August 15, 2013
Publication Date
January 1, 1990
Subject Category
Meeting Information
Intersociety Energy Conversion Engineering Conference(Reno, NV)
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