Properties of undoped and p-type hydrogenated amorphous silicon carbide films

The properties of undoped and p-type hydrogenated amorphous silicon carbide (a-Si-C:H) films were studied. The a-Si-C:H films were prepared under different deposition conditions by the r.f. glow discharge decomposition of gas mixtures of silane and methane in an inductively coupled system. The p-type a-Si-C:H films were prepared from mixtures of silane, methane and diborane gases. The dark conductivity, photoconductivity, optical absorption, band gap and spectral response of these films were studied. By analysing the dark and photoconductivity data, information about the transport mechanism and the recombination processes in these films was obtained. It is suggested that there is possibly a significant change in the structure of a-Si-C:H films with an increase in the carbon concentration that influences various properties of the material