Investigating the PTF Fully-Isolated NTA Space-grade CMOS Image Sensor Pixels

Space radiation can easily cause damage to the performance of CIS pixel devices, leading to varying degrees of failure in aerospace-grade microelectronic systems and a significant decline in image quality. This article proposes a PTF fully-isolated NTA radiation-hardening technology, which effectively suppresses the dark current generated by radiation-sensitive nodes by isolating the PPD photosensitive N-doped region, TG channel, FD-doped region, and STI edge. The results show that this technology can reduce the dark current growth rate to less than 72% following 50krad(Si) radiation exposure, down from 193%. The dark current growth per unit radiation dose is only 0.28pA•cm
^-2
•krad(Si)
^-1
, providing a solid theoretical basis and technical support for the development of advanced space-grade CMOS image sensors.