It has been found that a-Si:H layered films deposited by the cyclic method with intermediate annealing in hydrogen plasma have a room temperature high photosensivity by more than one order of magnitude exceeding that of standard undoped a-Si:H films grown by plasma deposition in RF glow discharge. The high photosensivity is caused by the low dark conductivity and high photoconductivity of the layered films at room temperature. We show that this can be caused by the presence of «sensitization» levels connected with a higher oxygen concentration on the layer boundaries and a low concentration of silicon dangling bonds in more ordered layers.

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