Cathodoluminescence study of irradiated p+n GaAs solar cells

In this paper, cathodoluminescence (CL) spectra were measured on p⁺n GaAs solar cells after irradiation by protons at different fluences and energies. A damage constant (τ₀K_τ) is determined at each proton energy by monitoring changes in the emitted CL intensity. The energy dependence of the CL damage constant is compared with the calculations of nonionizing energy loss (NIEL). It was found that the energy dependence of the CL damage constant closely tracks that for the open circuit voltage.