Ultra-Lightweight, High-efficiency (45%) Si-Based Triple Junction Solar

Next-generation satellites require increased payload mass and power budget capabilities. Ultra lightweight, 40% efficient solar cells employing Silicon substrates will allow for a significant power level scale up for a fixed solar panel size. The purpose of this proposal is to successfully demonstrate a high-efficiency Si-based solar cell technology. To achieve this goal, we ultimately will develop triple junction solar cells that employ Si substrates as a 1.1 eV bottom cell and heterogeneous III-V layers as a 1.5-1.7 eV middle cell and 1.9-2.1 eV top cell. Our advanced, next generation design will enable extremely high efficiency by using materials with ideal band gaps for the highest possible efficiency solar cells, and Si substrates (> 2x lower density than Ge) will reduce the solar cell payload mass by more than two times over current Ge-based technology.