Nature of Interface Defect Buildup in Gated Bipolar Devices Under Low Dose Rate Irradiation

The buildup of radiation-induced switching states in ELDRS-sensitive bipolar base oxides is measured with dc current-voltage and charge pumping techniques. These states include both faster interface traps (Pb) centers) and slower border traps. After irradiation, border traps and interface traps mostly decrease with annealing time and temperature in devices irradiated at 0 V. However, for devices irradiated at -50 V, there is a decrease in border trap density but an increase in interface trap density. These differences in interface-trap buildup and annealing are attributed to the dependence of defect passivation and depassivation on the concentrations of hydrogen and dangling Si bond defects near the Si/SiO2interface