The attraction for amorphous Silicon based alloys (a-Si) stems in large part from its ease in its depositing uniformly over large areas in a cost effective manner. We here at Glasstech Solar, Inc. (GSI) wish to report on the development of a-Si films for electrophotographic applications. For this specific purpose we have developed thick films (˜30–40 μm) of intrinsic a-Si deposited on TCO at deposition rates of up to 14 Å/S We tested the material for its photoconductivity and breakdown voltage, and its suitability for the application at hand with one measured parameter, the 400 volt switching time, TΔ400. Essentially the goal consisted of developing a high voltage photoconductive switch, that would swing 400 volts at the terminals in a few μsec.