Permanent Damage Produced by Single Proton Interactions in Silicon Devices

Results of measurements of the permanent damage produced by single energetic proton interactions in silicon depletion regions are presented. Single damage events and damage distributions were measured for an image sensor bombarded with 99- and 147-MeV protons. Increases in dark current density by more than two orders of magnitude were observed for individual damaged cells at relatively low fluences. Results are in good agreement with fundamental proton interaction concepts and with statistical expectations. Interesting phenomena are revealed in a study of room-temperature annealing, including damage production long after irradiation. Comparison of the effects of energetic proton bombardment with those produced by 14-MeV neutron irradiation is made, and similarities and differences are noted. Implications of this work for small-geometry integrated circuits are considered, and the relevance of this investigation to gaining increased understanding of proton damage mechanisms is discussed.