PHOTOVOLTAIC DEVICE

摘要

A multijunction tandem photovoltaic device is disclosed having a bottom subcell of silicon germanium or silicon germanium tin material and above that a subcell of gallium nitride arsenide antimonide material. The materials are lattice matched to gallium arsenide, which preferably forms the substrate. Preferably, further lattice matched subcells of gallium arsenide, indium gallium phosphide and aluminium gallium arsenide or aluminium indium gallium phosphide are provided.