Interface trap formation via the two-stage H/sup +/ process

The time dependence and oxide-field dependence of interface trap (N/sub it/) formation in MOSFETs have been studied following pulsed ionizing radiation. Results are compared with the so-called two-stage model for N/sub it/ formation involving slow drift of radiation-induced H/sup +/ ions in the SiO/sub 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/sup +/ throughout the oxide. Calculations based on this model correctly predict the complete time-dependent N/sub it/ formation curves. It is also shown that N/sub 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/sup +/ production during the first stage.<
>