Method for producing a self-alignment type ccd sensor

Abstract

A process for producing a CCD image sensor comprising the steps of: providing a light-receiving photo-diode region and a VCCD transmission region by injecting ions into a substrate at a predetermined distance, the injected ions being different in type from the substrate, covering the surface of the substrate with a gate oxide layer and a gate polysilicon layer, the gate polysilicon layer being deposited over the gate oxide layer, then removing the gate polysilicon layer only from the region over the light-receiving region, depositing a refractory metal layer over the whole etched surface by vacuum evaporation and then annealing the refractory metal into a silicide in the region thereof which is in contact with the gate polysilicon and removing the refractory metal from the unconverted portion of the refractory metal layer which overlies the gate oxide layer. In this process, a fill factor of the light-receiving region is maximized as a window is provided in the light-receiving region by self-alignment, and smear is prevented as silicide completely covers the gate polysilicon layer including even the side faces thereof.