The study of the carriers' transport mechanism of GaAs/Ge solar cells based on irradiation damage model

Based on the irradiation damage model of solar cells, the irradiation damage mechanism of space solar cells from the aspect of the carriers' transport is studied. The basic rules of electrical parameter degradation of GaAs/Ge solar cells under different energy proton and electron irradiation are obtained through the ground-accelerated equivalent simulation test for space-charged particles. The open-circuit voltage degradation curves of the solar cells are fitted nonlinearly by its mathematical model. The change laws of damage coefficient of majority carriers' removal rate with the incident proton and electron energy are given. The damage coefficient of GaAs/Ge solar cells first increases and then decreases with increasing incident proton energy, and it reaches a maximum at 100 keV proton irradiation. In addition, the damage coefficient increases with increasing incident electron energy. The studies show that open-circuit voltage degradation is closely related to the removal effect of the majority carriers under charged particle irradiation. The results have important significance to reveal the irradiation damage mechanism of the space solar cells.