Radiation-Induced Dose and Single Event Effects in Digital CMOS Image Sensors

This paper focuses on radiation-induced dose and single event effects in digital CMOS image sensors using pinned photodiodes. Proton irradiations were used to study cumulative effects. As previously observed, the dark current is the main electrical parameter affected by protons. The mean dark current increase appears proportional to Srour´s universal damage factor. Therefore, the degradation is mainly attributed to displacement damage in the pinned photodiode. Heavy ion tests are also reported in this work. This study focuses on single event effects in digital CMOS imagers using numerous electronic functions such as column ADCs, a state machine and registers. Single event transients, upsets and latchups are observed and analyzed. The cross sections of these single events are transposed to specific space imaging missions in order to show that the digital functions can fit the mission requirements despite these perturbations.