Radiation resistance of MBE-grown GaInP/GaAs cascade solar cells flown onboard Equator-S satellite

The radiation resistance of GaInP/GaAs cascade solar cells grown by molecular beam epitaxy (MBE) was tested onboard Equator-S satellite. The short-circuit current, open-circuit voltage, and power data were obtained for a period of about half a year. The remaining factors of these parameters were determined at the standard end-of-life (EOL) condition of an equivalent dose of 1×10¹⁵ cm⁻² 1 MeV electrons. Electron irradiation tests were also performed in the laboratory. Consistent results were obtained with flight and laboratory data. The remaining power at the EOL condition was 0.89–0.90 for these cells.