Silicon gate CCD structure

Claim 1

In a method of fabricating a charge coupled device structure having adjacent overlapping phase electrodes extending transversally over a channel formed in a semiconductor substrate, said phase electrodes separated from each other and from the underlying semiconductor substrate by a single insulator material, the steps of: ion implanting spaced apart first surface potential modified regions in said semiconductor substrate and extending across said channel, said regions located beneath a surface of said substrate covered by a uniform thickness insulating material, forming spaced apart polycrystalline semiconductor electrode strips extending across said channel and partly overlying portions of said doped regions, removing insulating material between said polycrystalline semiconductor strips and replacing said removed insulating material by a layer of said same insulating material to said uniform thickness and to cover said polycrystalline semiconductor strips using a process causing significant diffusion of dopant impurities into said insulating material from semiconductor surface areas not overlaid by said polycrystalline semiconductor strips; forming mask material over portions of said insulation material between said polycrystalline strips and ion implanting second modified surface potential regions in said semiconductor surface beneath areas of said insulating material between said polycrystalline semiconductor strips and respectively bounded by an edge of said mask material and an edge portion of a polycrystalline strip covered by insulating material beneath which there is no implanted first modified surface potential region, said first and second modified surface potential regions being formed by implanted dopant ions of the same conductivity type; and forming conductive electrodes over said insulation material between said polycrystalline strips to overlap marginal portions of said polycrystalline strips.