Selenium Interlayer for High-Efficiency Multi-Junction Solar Cell

Innovators at NASA’s Glenn Research Center have developed a low-cost, high-efficiency solar cell that uses a thin layer of selenium as the bonding material between wafers. Selenium is a semiconductor, and it is also transparent to light at photon energies below the band gap. The innovation allows a multi-junction solar cell to be developed without the constraint of lattice matching, and uses a low-cost, robust silicon wafer as the supporting bottom substrate and bottom cell. This enables a cell that is simultaneously lower in cost, more rugged, and more efficient than existing space solar cell designs. This technology has the potential to be used in next-generation solar cells in space, and it can be commercialized for terrestrial applications such as power plants and smart grid systems.