Proton radiation damage and temperature response mechanism of CMOS image sensor for space high-precision metering

Abstract

The exoplanet transit telescope uses high-precision CMOS image sensor for planet searching. This device operates at 233 K to reduce dark current and noise interference on the effective signal. This paper examines the effects of space proton radiation on the performance of high-precision CMOS image sensor through proton irradiation and post-irradiation testing at various temperatures. The results indicate that proton irradiation degrades parameters like dark current, dark signal, and fixed pattern noise, with dark current being the most sensitive. As the operating temperature increases, radiation-sensitive parameters degrade rapidly, significantly impairing sensor performance. This indicates that lower temperatures provide better performance. Notably, Dark signal distribution fluctuates with temperature. Compared to before irradiation, the Gaussian mean decreases at 233 K and increases between 243 and 273 K. At low temperature, the ionization damage caused by proton radiation mainly results in the decrease of Gaussian mean, while the displacement damage mainly results in the increase of this. The study concludes that proton-induced displacement damage, which leads to bulk defects, is the primary cause of performance degradation. This provides essential data and foundational support for radiation damage assessment and on-orbit applications.