Ultra-thin Single-junction GaAs Solar Cells For Extreme Space Environments

Ultra-thin (less than 100 nm) photovoltaics for space power applications are proposed due to their intrinsic radiation tolerance [1]. They are a potentially enabling technology for space missions in high radiation environments such as Highly Elliptical Earth Orbits (HEO) and the orbits of Jupiter's scientifically interesting moon, Europa. GaAs solar cells with an 80 nm active layer were designed, fabricated and tested under 68 MeV proton irradiation. The results of electrical characterisation before and after proton beam exposure at two different fluences shows their tolerance to these harsh conditions.