Process for the preparation of image-reading photosensor

Claim 1

In the process for preparing an improved image-reading photosensor having a substrate, a photoeletric conversion layer formed from a film of non-single crystalline semiconductor material and an electrode electrically connected to the photoelectric conversion layer, the improvement which comprises: (a) introducing via first gas transportation conduit into an evacuated film-forming space having said substrate therein a gaseous substance (i) capable of being a constituent for said film, but essentially incapable of contributing to the formation of said film in its original energy state, and separately through a second gas transportation conduit concentric with said first gas transportation conduit a gaseous substance (ii) capable of electronically oxidizing the substance (i), said first and second concentric gas transportation conduits terminating adjacent said substrate; (b) chemically contacting said gaseous substances (i) and (ii) in the absence of a plasma in the space adjacent the surface of said substrate; said substrate being maintained at an elevated temperature to generate a plurality of precursors containing excited precursors and to cause at least one of said precursors to form the film constituting the photoelectric conversion layer; and (c) maintaining the distance between the outlet of said first and second concentric gas transportation conduits and the surface of said substrate from 5 mm to 15 cm.