Performance Evaluation and Prediction of Single-Junction and Triple-Junction GaAs Solar Cells Induced by Electron and Proton Irradiations

Space-graded single-junction (SJ) and triple-junction (TJ) GaAs solar cells, produced by MOCVD, are evaluated through different energy electron- and proton-irradiations to compare radiation effects on these solar cells. Mean degradations of the short circuit current, open circuit voltage and maximum power are presented and analyzed. Compared to the radiation data of the single-junction GaAs cell, the triple-junction GaAs cell has a superior radiation-hardness performance at the same electron or proton energy and fluence. Degradations at different electron or proton energies have been correlated with displacement damage dose. Monte Carlo calculations were completed to analyze displacement damage dose deposited in the solar cell active regions by space radiation environments. The performance degradations of both solar cells in space were predicted. This study provides reference data for the design of these GaAs solar arrays in the typical space radiation environments to ensure the security and reliability of on-orbit spacecrafts.