Displacement Damage in CMOS Image Sensors After Thermal Neutron Irradiation

Abstract

In this paper, CMOS image sensors were exposed to thermal neutrons observing an increase in the dark signal of many pixels. The effect was found to be similar to the damage caused by alpha particles irradiation. Rutherford backscattering spectroscopy (RBS) and SIMNRA simulation were used to confirm that the sensors contain boron in the insulation layers. The damage produced by thermal neutrons is explained as displacement damage caused by alpha particles and lithium-7 ions in the silicon active volume of the sensors after boron-10 thermal neutron capture.