MULTIJUNCTION SOLAR CELL AND SOLAR CELL ASSEMBLIES FOR SPACE APPLICATIONS

摘要

A multijunction solar cell having an upper first solar subcell composed of a semiconductor material having a first band gap; a second solar subcell adjacent to said first solar subcell and composed of a semiconductor material having a second band gap smaller than the first band gap and being lattice matched with the upper first solar subcell; a third solar subcell adjacent to said second solar subcell and composed of a semiconductor material having a third band gap smaller than the second band gap and being lattice matched with the second solar subcell; a fourth solar subcell adjacent to and lattice mismatched from said third solar subcell and composed of germanium grown on a growth substrate. In some embodiments of a five junction solar cell, the growth substrate forms a bottom solar subcell and is composed of germanium.