Electronic shutter using buried layers and active pixel sensor and array employing same

Abstract

An electronic shutter switching transistor for a CMOS electronic is formed in a semiconductor substrate of a first conductivity type. The transistor comprises a pair of spaced apart doped regions of a second conductivity type opposite the first conductivity type disposed in the semiconductor substrate forming source/drain regions. A gate is disposed above and insulated from the semiconductor substrate and is self aligned with the pair of spaced apart doped regions. A well of the second conductivity type laterally surrounds the pair of spaced apart doped regions and extends deeper into the substrate than the doped regions. A buried layer of the second conductivity type underlies and is in contact with the well.