SOLID-STATE PHOTODETECTOR PIXEL AND PHOTODETECTING METHOD

摘要

A pixel (1) is formed in a semiconductor substrate (S) with a plane surface for use in a photodetector. It comprises an active region for converting incident light (In) into charge carriers, photogates (PGL, PGM, PGR) for generating a lateral electric potential (¦(x)) across the active region, and either at least one integration gate (IG) for storing charge carriers generated in the active region and at least one dump site (DDiff) or at least two integration gates, the integration gates (IG) and the dump-site (DDiff) being placed outside the active region. The pixel (1) further comprises separation-enhancing means (SL) for additionally enhancing charge separation in the active region and charge transport from the active region to the integration gate (IG). The separation-enhancing means (SL) are for instance a shield layer designed such that for a given lateral electric potential (¦(x)) having an apse (min) in the active region, the incident light (In) does not impinge on the section from which the charge carriers would not be transported to the integration gate (IG). Thus, the shutter efficiency is enhanced.