Doping of a-SiCX:H films including μc-Si:H by hot-wire CVD and their application as a wide gap window for heterojunction solar cells

Impurity doping using B₂H₆ gas using hot-wire CVD has been tried for hydrogenated amorphous silicon-carbon (a-SiC_X:H) alloy films including hydrogenated microcrystalline silicon (μc-Si:H) with carbon content, C/(Si+C), of about 28%. The dark- and photoconductivities of B-doped samples are larger than those of undoped samples. The activation energy for dark conductivity of the B-doped sample with the doping gas ratio, B₂H₆/(SiH₄+CH₄), of about 0.054% is 0.17 eV. This value is smaller than that of the undoped sample. The P-doped samples also show larger dark- and photoconductivities and smaller activation energy than the undoped samples.