ELECTRON INJECTION INTO THE GATE OXIDE OF MOS STRUCTURES AT LIQUID-NITROGEN TEMPERATURE - MEASUREMENT AND SIMULATION

Measured electron injection probabilities (P-JN) into the gate oxide o f MOS structures [1] are presented for both liquid nitrogen and room t emperature. For the first time P-JN has been measured for total voltag e drops (V-TOT) in the substrate spanning from well below to well abov e the value corresponding to the Si-SiO2 barrier height (V(TOT) = phi (B)/q = 3.15 V). In contrast to MOSFET data [2], here two different in jection regimes can clearly be distinguished. For V-TOT<V(TOT) a regi me occurs in which injection is no longer caused only by the electron energy gained in the electric field but also by the additional energy from phonon absorption. No lucky electron model holds true in this reg ime and therefore some insight will be given here by means of Monte Ca rlo simulations of the injection experiment A simple analysis techniqu e is developed, that explains the observed temperature dependence and injection regimes of P-JN.