Bias and thermal annealings of radiation-induced leakage currents in thin-gate oxides

The effects of bias annealing and thermal annealing on radiation-induced leakage currents (RILC) in thin-gate oxides (4.5 nm) have been studied. To decouple these two effects, we have performed the bias annealing at room temperature and the thermal annealing at elevated temperatures without bias. RILC has been found to decrease after both bias and thermal annealings. We have also observed that the decrease of RILC during bias annealing was greatly enhanced in a hydrogen ambient. This evidence strongly indicates that trapped holes contribute significantly to RILC and suggests that the bias annealing of RILC was likely due to the annealing of trapped holes.