Enhancing ordering in strained GaInP and open-circuit voltage uniformity in strained GaInP/metamorphic GaInAs/Ge triple junction solar cells by a small amount of surfactant.
Shih-Chang Tong1*, Shu-Wei Wu2, Pai-Chun Wei3, Da-Wei Yeh1, Chih-Hung Wu2, Jyh-Shyang Wang1
1Department of Physics, Chung Yuan Christian University, Chung-Li, Taiwan
2Institute of Nuclear Energy Research, Longtan, Taiwan
3Institute of Physics, Academia Sinica, Taipei, Taiwan
* presenting author:童世昌, email:shihchang0623@gmail.com
Strained GaInP/metamorphic GaInAs/Ge triple junction solar cells grown by metalorganic chemical vapor deposition with introducing a small amount of surfactant during the strained GaInP top cell growth were investigated. The cross-sectional transmission electron diffraction (TED) patterns of the strained GaInP epilayers which was grown under our normal growth conditions without surfactant only showed the regular zincblende spots, while small superspots between regular zincblende spots due to the CuPt ordering was clearly observed in the TED pattern of the strained GaInP epilayer which was grown under our normal growth conditions but with introducing a small amount of surfactant. The photoluminescence spectra revealed that the optical quality of these strained GaInP epilayers were essentially the same. Moreover, we demonstrated a significant improvement in the uniformity of device open-circuit voltage over a quarter of wafer in 4 inch size by using a small amount of surfactant.


Keywords: Strained GaInP, metamorphic, metalorganic chemical vapor deposition, surfactant