GaInN-Based Solar Cells Using Strained-Layer GaInN/GaInN Superlattice Active Layer on a Freestanding GaN Substrate

Abstract

High-performance GaInN-based solar cells with high open-circuit voltage, high short-circuit current density, and good fill factor have been obtained using a combination of two different GaInN superlattice structures. The GaInN barrier thicknesses (3 and 0.6 nm) in both superlattice structures were optimized, resulting in a thick GaInN-based active layer with a low pit density in the device. The conversion efficiency is approximately 2.5% under a solar simulator of air mass 1.5G and an irradiation intensity of 155 mW/cm2.