Physical principles of self-consistent simulation of the generation of interface states and the transport of hot charge carriers in field-effect transistors based on metal–oxide–semiconductor structures

A detailed simulation of degradation (caused by hot charge carriers) based on self-consistent consideration of the transport of charge carriers and the generation of defects at the SiO$_2$/Si interface is carried out for the first time. The model is tested using degradation data obtained with decananometer $n$-type-channel field-effect transistors. It is shown that the mutual influence of the above aspects is significant and their independent simulation gives rise to considerable quantitative errors. In calculations of the energy distribution for charge carriers, the actual band structure of silicon and such mechanisms as impact ionization, scattering at an ionized impurity, and also electron–phonon and electron–electron interactions are taken into account. At the microscopic level, the generation of defects is considered as the superposition of single-particle and multiparticle mechanisms of breakage of the Si–H bond. A very important applied aspect of this study is the fact that our model makes it possible to reliably assess the operating lifetime of a transistor subjected to the effects of “hot” charge carriers.