Split gate electrode, self-aligned antiblooming structure and method of

Abstract

Excess signal charge generated in response to optical overload of a charge-coupled sensing region is removed from that region by an antiblooming drain implanted in the substrate of the sensing array. The antiblooming drain is separated from the row of sensing regions by a potential barrier produced by a gate electrode associated with the drain. In fabricating the charge-coupled optical imager, the antiblooming drain is self-aligned with the antiblooming gate electrodes by first providing a pair of spaced-apart antiblooming gate electrodes and implanting the drain region into the substrate using the gate electrodes as a mask.