Radiation response of triplejunction solar cells designed for terrestrial application

Oshima, Takeshi; Imaizumi, Mitsuru*; Takamoto, Tatsuya*; Sumita, Taishi*; Oi, Akihiko; Kawakita, Shiro*; Ito, Hisayoshi; Matsuda, Sumio*

The effects on proton and electron irradiateions of the characteristics of InGaP/GaAs/Ge triple junction designed for terrestrial application were studied. The solar cells used in this study has a 1% In-contained GaAs middle sub-cell, and their efficiency is more than 30 % under AM1.5, which is the highest efficiency of all solar cells in the world.As the results of 1MeV-electron and 10 MeV-proton irradiation, terrestrial triple-junction sole cells were found to have the same radiation resistance as space single junction GaAs solar cells, although terrestrial triple-junction solar cells is not stronger than space triple-junction solar cells made in USA. As the result of proton energy dependence of the electrical characteristics and quantum efficiency, the strong degradation of the GaAs middle cell was observed.