Device quality a-SiGe:H films for multijunction solar cells

Hydrogenated amorphous silicon-germanium films of different optical band gaps have been prepared by rf glow discharge method and their opto-electronic properties have been investigated. Photovoltaic quality of the material has been estimated in terms of a conceptually new Quality Factor, Q = photoconductivity X photosensitivity. At a deposition temperature of 250°C, films of Eg = 1.53 eV with O=5.6×101 have been reported.