High-radiation-resistant InGaP, InGaAsP, and InGaAs solar cells for multijuction solar cells

The radiation response of 3 MeV proton-irradiated InGaP, InGaAsP and InGaAs solar cells was measured and analyzed in comparison with those of InP and GaAs. The degradation of the minority-carrier diffusion length was estimate d from the spectral response data. The damage coefficient K-L for the 3 MeV proton-irradiated InGaP, InGaAsP and InGaAs was also determined. The radia tion resistance increases with an increase in the fraction of In-P bonds in InGaP, InGaAsP and InGaAs. Differences in the radiation resistance of InGa P, InGaAs and InGaAs materials are discussed. Minority-carrier injection un der forward bias is found to cause partial recovery of the degradation on i rradiated InGaP and InGaAsP cells. (C) 2001 American Institute of Physics.