Temperature quenching of photoconductivity in undoped specimens of amorphous hydrogenated silicon obtained at different deposition temperatures

A complex of methods was used to study the following properties of undoped a-Si:H specimens: absorption (by the dc photocurrent technique), concentration of dangling bond (DB) type defects (by the EPR technique), and temperature dependence of dark and photoconductivity. To explain the results obtained, a model was proposed which allows, in addition to the growth of DB defect concentration, also for the growth of concentration of shallow centers with energies near the valence band in the a-Si:H mobility gap.