Method for producing photosensitive film for electrophotography

摘要

Disclosed are method and apparatus for producing highly uniform films of photosensitive materials (e.g., amorphous silicon) for electrophotography on large diameter cylindrical metal substrates (e.g., aluminum or stainless steel) by plasma chemical vapor deposition (CVD). The cylindrical substrate is rotatably mounted in a reaction chamber and serves as an electrode. A hollow metallic second electrode in the reaction chamber coaxially surrounds the substrate and is spaced apart therefrom. Hydrogen gas is first introduced into the inter-electrode space between the substrate and the second electrodes, and a high-frequency electric field is applied to the two electrodes to generate a glow discharge for plasma cleaning of the substrate surface. The hydrogen gas is then pumped out of the reaction chamber, and a reaction gas of monosilane (SiH4) is then flowed through the inter-electrode space and a glow discharge is again generated between the electrodes to decompose the silane and to cause amorphous silicon to deposit on the surface of the substrate. During deposition both the substrate and the second electrode are electrically heated. The reaction gas is introduced and exhausted in a manner such that reaction gas density in the inter-electrode space is uniform along the axial direction.