학술논문
Enhanced-Depletion-Width GaInNAs Solar Cells Grown by Molecular-Beam Epitaxy
Document Type
Conference
Author
Source
Other Information: Presented at the 2004 DOE Solar Energy Technologies Program Review Meeting, 25-28 October 2004, Denver, Colorado. Also included in the proceedings available on CD-ROM (DOE/GO-102005-2067; NREL/CD-520-37140)
Subject
Language
English
Abstract
The 3-junction, GaInP2/GaAs/Ge solar cell is a non-optimized structure due to excess light falling on the Ge junction. Because of this, a fourth junction inserted between the GaAs and Ge subcells could use the excess light and provide an increase in device efficiency. Unfortunately, the leading candidate material, GaInNAs, suffers from very low minority-carrier diffusion lengths compared to its parent compound, GaAs. These low diffusion lengths do not allow for the collection of adequate current to keep the overall 4-junction structure current matched. If the currents generated from the GaInNAs subcell are increased, the possibility exists for practical efficiencies of greater than 40% from this structure.