Abstract
The effect of a modified PH3-to-AsH3 gas switching sequence with an AsH3 surge treatment on GaInP/GaAs dual-junction solar cells was studied. With AsH3 surge treatment, both the material quality with an absence of defects and device performance was preserved, but without it, deterioration in both of these characteristics was observed, which originated in the As/P interface. It was found that defects with an inhomogeneous III-metal composition were formed at the interface and developed into a V-shaped dislocation which penetrated the GaInP top cell. The results suggest that sufficient arsenic supply is necessary prior to As-based material growth on GaInP. (C) 2018 The Japan Society of Applied Physics