Proton and electron irradiation of MOCVD InP solar cells: Experimental results and radiation modeling

1 MeV electron and 10 MeV proton irradiation of high-efficiency (>18%, 1 sun, AM0) InP solar cells grown by metalorganic chemical vapor deposition (MOCVD) is reported. The MOCVD InP cells are shown to be more radiation resistant than Si and GaAs cells, especially at high fluences. Deep-level transient spectroscopy (DLTS) measurements on the InP solar cells are reported. The defect behavior is compared with cell parameters following irradiation and subsequent annealing stages. The correlation between changes in the solar cell output and the majority carrier (hole) DLTS spectrum reported in irradiated diffused junction InP was not observed in MOCVD InP. An approach to correlating electron- and proton-induced damage in InP solar cells based on calculations of the nonionizing energy loss (NIEL) is described.<
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