Degradation behavior of flexible a-Si/a-SiGe/a-SiGe triple junction solar cells irradiated with 20-350 keV protons

Sato, Shinichiro; Beernink, K.*; Oshima, Takeshi

The electrical performance degradation of a-Si/a-SiGe/a-SiGe triple-junction solar cells due to irradiation of protons with different energies and their performance recovery at room temperature just after irradiation are investigated. It was shown that the degradation behavior depended on incident proton energies. It was also shown that all the parameters (short-circuit current, open-circuit voltage, and fill factors) recovered with time after proton irradiation was stopped. In particular, the short-circuit current intensively recovered. This is due to the carrier diffusion length increase which is based on room temperature annealing of radiation defects.