Cathodoluminescence Study of 68 MeV Proton-Irradiated Ultra-Thin GaAs Solar Cells

The impact of high energy proton radiation, as would be encountered in highly eccentric and Europa orbits, on ultra-thin GaAs solar cells was studied. The cells were irradiated with 68 MeV protons at fluences of 2 × 10
¹²
cm
^-2
and 1 × 10
¹³
cm
^-2
. Cathodoluminescence and dark I-V were used to evaluate the variation of defect density and J
₀₂
with fluence, respectively. The applicability of cathodoluminescence to the study of radiation damage in photovoltaic devices is discussed.