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DOE OSTI · 1440218

FinalTechRep_DE_EE0007363_15

Ahrenkiel, Phil
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Abstract

The primary objective of the project was to develop Ga 0.82 In 0.18 As (GaInAs) solar cells grown on epilayers of elemental Al. At this composition, GaInAs has a nearly optimal bandgap (1.16 eV) for a single-junction photovoltaic device. However, GaInAs lacks a convenient, lattice-matched substrate, restricting most investigations to metamorphic structures. The metal Al is, in fact, precisely lattice-matched to GaInAs in the orientation GaInAs (001)[100]||Al(001)[110]. At present, however, epi-ready Al substrates are not readily available commercially and are subject to oxidation. However, epitaxial Al buffer layers could enable control of defect generation, thermal and light management, and rapid epitaxial lift-off for ultrathin devices.

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Ahrenkiel, Phil. 2018-05-25. FinalTechRep_DE_EE0007363_15. https://doi.org/10.2172/1440218

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