Analysis of Image Lag Degradation in PPD CISs Induced by Total Ionizing Dose and Displacement Radiation Damage

The experiments of the total ionizing dose (TID) and displacement radiation effects on the pinned photodiode (PPD) CMOS image sensors (CISs) are presented. The CISs are manufactured using a standard $0.18 \mu \text{m}$ CMOS technology with 4 Megapixels and 4-transistor PPD pixel architecture. The image lag degradation induced by TID damage is analyzed by exposing the 60Co $\gamma$ rays with different biased conditions. The experimental results show that the degradation of the biased CIS are more severe than that of the unbiased CIS. The image lag degradation versus the TID at the dose rates of 0.1, 1.0 and 10.0 rad(Si)/s are compared. The image lag degradation induced by displacement damage is also investigated by the proton and neutron radiation. The image lag degradation mechanisms caused by 60Co $\gamma$ ray, proton, and neutron radiation are analyzed with the TCAD simulation and the radiation particle transportation simulation using GEANT 4.