Difference in electron-and gamma-irradiation effects on output characteristic of color CMOS digital image sensors

Changes of the average brightness and non-uniformity of dark output images, and quality of pictures captured under natural lighting for the cotor CMOS digital image sensors irradiated at different electron doses have been studied in comparison to those from the γ-irradiated sensors. For the electron-irradiated sensors, the non-uniformity increases obvi- ously and a small bright region on the dark image appears at the dose of 0.4 kGy The average brightness inereases at 0.4 kGy, increases sharply at 0.5 kGy. The picture is very blurry only at 0.6 kGy, showing the sensor undergoes severe pen- formance degradation. Electron radiation damage is much more severe than γ radiation damage for the CMOS image sen- sors. A possible explanation is presented in this paper.