Temperature selectivity of the radiation effect on silicon MOS transistors

Using the technique of the subthreshold currents of metal–oxide–semiconductor (MOS) transistors in the temperature range of 290–450 K, the effect of the temperature conditions of X-ray irradiation on the kinetics of the parameters $U_{\mathrm{th}}$ and $D_{\mathrm{it}}$ of silicon MOS transistors with a channel length of 2–10 $\mu$m is studied. It was shown that, according to the parameters under study, the radiation sensitivity of transistors decreases at irradiation temperatures above 360 K (the temperature of the low-temperature maximum in the spectrum of a thermostimulated depolarization (TSD) transistor) and reaches a maximum near 430 K (corresponding to the high-temperature maximum). The results obtained are interpreted from the standpoint of a model of the existence of two carrier trap types, the redistribution of electrically active Na$^+$, K$^+$, Li$^+$, and H$^+$ ions between them under irradiation, and the effect of the partial neutralization of charges at the interface.