Radiation-Induced Defects in 8T-CMOS Global Shutter Image Sensor for Space Applications

Abstract

We propose to identify the displacement damage defects induced by proton and carbon irradiations in a commercial off-the-shelf pinned photodiode (PPD) 8T-CMOS image sensors (CISs) dedicated to space application operating in global shutter mode. This paper aims to provide a better understanding of defects creation in a specific space image sensor. Therefore, it leads to comparable results to those we could find during the mission. The study focuses on bulk defects located in the PPD depleted region which represents the main dark current contribution in PPD CIS. Four sensors have been irradiated with carbon ions and protons at different energies and fluencies. Using both the dark current spectroscopy and the random telegraph signal (RTS) analysis, we investigate defects behavior for different isochronal annealing temperatures. By combining these results, we make the connection between two complementary phenomena and bring out the prevalence of divacancies-based defects in term of dark current contribution.