Formation of interface traps in metal-oxide-semiconductor devices during isochronal annealing after irradiation at 78 K

Abstract

We have studied the mechanisms of interface trap (N_it) formation in metal‐oxide‐semiconductor devices during isochronal annealing after irradiation at 78 K. Two distinct N_it formation processes are observed at 120 and 250 K. After irradiation but before annealing, some samples were injected with electrons to remove all the radiation‐induced positive oxide charges. In these samples, the N_it formation process at 250 K is nearly eliminated, in agreement with previous reports, but the lower‐temperature 120 K process increases substantially. Results are explained using a hydrogen model. We also discuss the use of substrate hot‐electron injection, which is used to annihilate the radiation‐induced positive charge, in some detail.