Radiation Effect of Electron and Proton on InGaAsP (1.7 eV) Single-junction Solar Cells

This study focused on the radiation damage effects of 1 MeV electrons and 5 MeV protons on InGaAsP single-junction solar cells. Light J-V test results showed that the short-circuit current density (Jsc), open-circuit voltage (Voc) and maximum power (Pmax) degraded linearly with the logarithm of the electron and proton fluences. Based on the non-ionizing energy loss (NIEL) accurately calculated by Geant4, a displacement damage dose (DDD) model was applied to fit the degradation curves of 1 MeV electrons and 5 MeV protons without correction factors. The EQE curves indicated that under electron and low-fluence proton irradiation, the performance degradation was concentrated in the long-wavelength region, whereas high-fluence proton irradiation caused more severe short-wavelength degradation. Furthermore, thermal annealing experiments demonstrated that the performance recovery extent of the electron-irradiated (1 × 1015 cm–2) devices was higher than that of the proton-irradiated (1 × 1012 cm–2) devices; under both conditions, the performance recovery of the devices predominantly occurred in the long-wavelength spectral region.