Proton damage effects in EEV charge-coupled devices

Abstract

An examination is conducted of the effects of low-energy protons on CCD performance to evaluate the potential effectiveness of space-borne observational instruments. Degradation is described as a function of incremental dose, irradiation temperature, or proton energy for several device architectures, some of which incorporate design features to minimize signal-charge/trapping-site interaction. Degradation of the charge transfer is studied for very low proton doses, and dark current is found to vary directly with proton dose. Displacement damage in the signal-transfer channels generates charge-trapping sites that have a negative effect on EEV CCD performance. Degradation of charge-transfer performance is shown to be the most significant hindrance to effective CCD operations for X-ray spectroscopic applications.