Interface trap formation via the two-stage H+ process

The time dependence and oxide-field dependence of interface trap ( N_it) formation in MOSFETs have been studied following pulsed ionizing radiation. Results are compared with the so-called two-stage model for N_it formation involving slow drift of radiation-induced H⁺ ions in the SiO ₂. Detailed data on the gate-oxide-field dependence during each individual stage are presented and discussed. A model is developed for the production of H⁺ throughout the oxide. Calculations based on this model correctly predict the complete time-dependent N _it formation curves. It is also shown that N _it formation is at a maximum near zero first-stage gate bias. This unexpected behavior apparently arises from the oxide-field dependence of the H⁺ production during the first stage