A comparison between p+n and n+p GaAs displacement damage coefficients following proton irradiation

In this paper, the photovoltaic response of p⁺n and n⁺p GaAs solar cells is monitored as a function of proton fluence at different proton energies. The energy dependence of displacement damage coefficients (DCs) describing the photovoltaic degradation for these devices are compared with calculations of nonionizing energy loss (NIEL). The short circuit current DCs for both device types follows the same energy dependence. In contrast, the open circuit voltage DCs follows a different energy dependence at higher proton energies (E ≫ 10 MeV).