CMOS sense structure having silicon dioxide outer ring around sense region

Abstract

A CMOS structure having a silicon dioxide outer ring around the sense region. The CMOS sense structure has a substrate, a n− region, a n+ region, an isolation region, a field implant region and a silicon dioxide outer ring region. The n− region is formed in the substrate, and the n+ region is formed within the n− region. The isolation region is formed in the substrate next to the edge of the n− region. The field implant region is formed under the isolation region. The silicon dioxide outer ring region is formed over the n− region, a portion of the isolation region and a portion of the n+ region. The silicon dioxide outer ring can prevent surface leakage that is caused by etching and lengthening the distance from the n− region to the field implant region so that edge junction leakage is reduced.

Dependencies are inferred from the claim text.