Backside illuminated thinned CMOS image sensors for space imaging

This paper presents two aspects of ongoing research at Imec, to develop high-end CMOS APS sensors, optimized for space-born imaging. Both hybrid and monolithic thinned backside illuminated CMOS imagers with a unique combination of techniques and performance enhancing concepts have been developed. Here we report on their radiation tolerance and UV sensitivity, two critical characteristics for space science imaging instruments. Radiation testing, using both proton and gamma irradiation, of CMOS imagers proved that dark current performance did not significantly deteriorate. Also, initial test images taken under 185–400 nm illumination, showed the imagers to be UV sensitive.