Layered amorphous silicon photoconductor with surface layer having specific refractive index properties

Claim 1

A light receiving member suitable for use in a high-speed image-making system which comprises at least a substrate and a light receiving layer, said light receiving layer comprising from the substrate side: (i) a photoconductive layer from 3 to 100 microns in thickness of a material selected from (a) an amorphous material containing silicon atoms as a matrix and at least one kind selected from hydrogen atoms and halogen atoms and (b) an amorphous material containing silicon atoms as a matrix, at least one kind selected from germanium atoms and tin atoms, and at least one kind selected from hydrogen atoms and halogen atoms, and (ii) a surface layer from 0.003 to 30 microns in thickness having a free surface and formed of an amorphous material containing silicon atoms and at least one kind selected from the group consisting of carbon atoms, oxygen atoms and nitrogen atoms (C,O,N) in a total amount of 0.5 to 95 atomic percent; said atoms (C,O,N) being present in a concentration sufficient to provide a refractive index value for the portion of the surface layer at the interface between the photoconductive layer and the surface layer such that the difference in refractive index (Δn) between the refractive index of the photoconductive layer and the refractive index of the portion of the surface layer at the interface is no greater that 0.62 and wherein the difference ΔE gopt between the optical band gap of the portion of the surface layer at said interface and the optical band gap of the photoconductive layer is no less than 0.01, wherein the atoms (C,N,O) are present in a low concentration at the interface side of the surface layer and are present in a high concentration at the free surface side of the surface layer and whereby said Δn and said ΔE gopt values tending to inhibit formation of interference fringe and ghost images, without compromising spectral sensitivity of said light receiving member.