Ultrathin silicon (Si) solar cells for space application were fabricated on an experimental basis and the electrical characteristics were investigated for three kinds of cells (Black, BSFR and Conventional cells). Under 135.3 mW/cm2 (AMO) illumination, ultrathin Black cells showed 67.7 mW output, which is equal to 89% output of 280 µm Black cells. The power to mass ratio of bare ultrathin Black cells was 3.6 times high compared with 280 jum thick Black cells. 1 MeV electron irradiation test was carried out to evaluate the radiation resistance. Ultrathin cells showed superior radiation resistance compared with that of 280 µm thick cells, and it was comparable to that of a GaAs solar cell which had been recognized as a radiation resistive cell.
Our experiments suggest that the ultrathin solar cells have high potential to be used for space application.