Research status of dark current in CMOS image sensor

After more than 50 years of development, CMOS image sensor has become the most mainstream image sensor. At present, the most used solid-state imaging devices directly image optical signals through the internal photoelectric effect, while the EBCMOS(electron bombardment CMOS) is more popular in the military field. In order to achieve low illumination and high quality image detector, people put forward higher requirements for the minimum operating illumination, fixed pattern noise, dynamic working range and other indicators of CMOS image sensor, and dark current is an important factor affecting these indicators. There are many literatures about the research of dark current in CMOS image sensor, but there is no systematic report on the research of dark current in CMOS image sensor. This paper systematically summarizes the research situation of dark current in CMOS image sensor. In this paper, the mechanism of dark current generation of CMOS image sensor is summarized firstly. Secondly, the influence of structure design, fabrication process and working environment on the dark current index of CMOS image sensor is summarized respectively, and the research situation of dark current compensation method is summarized again. Finally, combining with the generation mechanism of dark current of CMOS image sensor, the formation mechanism and influencing factors of dark current of new proposed electron bombardment CMOS(EBCMOS) image detector are analyzed.