MICROLINK DEVICES INC — National Aeronautics and Space Administration SBIR Phase I: S3.01

Description

MicroLink proposes to develop a phosphide-based ELO-IMM four-junction (4J) solar cell that will enhance the performance and capabilities of solar photovoltaic arrays for a variety of future NASA missions. Relative to state-of-the-art incumbent GaInP/GaInAs/Ge 3J space solar cells, the proposed phosphide-based 4J solar cell has superior radiation tolerance, higher beginning-of-life (BOL) and end-of-life (EOL) efficiencies, lower areal mass density, higher specific power, and lower cost. The improved radiation tolerance is enabled by eliminating arsenide-based subcells in favor of only phosphide-based subcells. A reduction in the mass of the solar cell relative to incumbent technology is enabled by removal of the thick GaAs substrate. Cost savings compared to incumbent technology are enabled by the recovery and reuse of the substrate via the ELO process. The superior radiation tolerance can also relax the requirements for radiation shielding, enabling further reductions in array mass and stowed volume.