Total Ionizing Dose Radiation-Induced Dark Current Random Telegraph Signal in Pinned Photodiode CMOS Image Sensors

In this paper, several studies on total ionizing dose effects on pinned photodiode CMOS images sensors are presented. More precisely, the evolution of a parasitic signal called random telegraph signal (RTS) is analyzed through several photodiode designs. It is shown that the population of pixels exhibiting this fluctuation depends on the design variants. This population also increases in a different way with the dose: the effects are not the same considering a low or high X-rays irradiation. Moreover, a statistical analysis is realized in order to better characterize the defects responsible for RTS. It turns out that an electric-field enhancement signature can appear in some specific cases.