Output circuit device for a charge transfer element having tripartite diffusion layer

Claim 1

An output circuit device for a charge transfer element, comprising: a semiconductor body; a wiring line layer formed on an upper surface of the semiconductor body; and a diffusion layer formed in the semiconductor body underneath the wiring line layer, the diffusion layer comprising first, second and third diffusion regions, the first diffusion region comprising a diffusion of a low concentration of an impurity having a high diffusion coefficient, the second diffusion region positioned within an upper surface portion of the first diffusion region in self-alignment with the first diffusion region and comprising a diffusion of a high concentration of an impurity having a low diffusion coefficient, the third diffusion region positioned in self-alignment with the first and second diffusion regions and extending from the upper surface where said wiring line layer contacts the upper surface of the semiconductor body and through the first and second regions to beneath the first diffusion region and having a diffusion of a high concentration of an impurity having a high diffusion coefficient, the high and low diffusion coefficients being high and low relative to one another, the high and low concentrations being high and low relative to one another.