THE TEMPERATURE DEPENDENCE OF THE PHOTOCONDUCTIVITY IN a-Si:H/a-SiN_x:H SUPERLATTICES

The temperature dependence of the photoconductivity σ_p(T) in a-Si:H/a-SiN_x:H superlattices does not decrease with temperature decreasing in the range of 120-250K, but it is temperature independent showing a wide plateau of photoconductivity σ_p in the superlattices with thickness of a-Si:H layer d_si=12 and 57nm. The plateau of σ_p(T) depends on the light intensity. One type of interface state as sensitizing centre was proposed. The parameters of the sensitizing centre were determined by using computer fitting of σ_p(T). The computed results are the same with the experimental data.