A thin film, hydrogenated, silicon based semiconductor alloy material is produced by a VHF energized plasma deposition process wherein a process gas is decomposed in a plasma so as to deposit the thin film material onto a substrate. The process is carried out at process gas pressures which are in the range of 0.5-2.0 torr, with substrate temperatures that do not exceed 300.degree. C., and substrate-cathode spacings in the range of 10-50 millimeters. Deposition rates are at least 5 angstroms per second. Also disclosed are photovoltaic devices which include the semiconductor material.
STATEMENT OF GOVERNMENT INTEREST
 This invention was made, at least in part, under U.S. Government, Department of Energy, Contact No. DE-FC36-07G017053. The Government may have rights in this invention.