Ultra-thin photovoltaics for radiation-tolerant space power systems

Ultra-thin (less than 100 nm thick) photovoltaics are proposed as an enabling technology for space power applications due to their intrinsic radiation tolerance. Outside of the Earth's atmosphere, spacecraft are bombarded with energetic electrons and protons which can cause dislocations in the lattice structure of their solar cell materials thus limiting mission lifetimes. Certain orbits that could be advantageous for imaging, security and network coverage of the Earth are currently inaccessible due to high levels of radiation making them inhospitable to space craft. Ultra-thin cells have superior radiation tolerance but lower optical absorption which necessitates the integration of a nanophotonic light-trapping structure. The first iteration of ultra-thin 80 nm absorber layer devices patterned by Displacement Talbot Lithography has shown promising electrical and optical performance.