Proceedings of the Second European Workshop on Low Temperature Electronics
J. Phys. IV France 06 (1996) C3-19-C3-24
Electron Injection into the Gate Oxide of MOS Structures at Liquid Nitrogen Temperature : Measurement and SimulationB. Fischer1, L. Selmi1, A. Ghetti1 and E. Sangiorgi2
1 DEIS, University of Bologna, Viale Risorgimento 2, 40136 Bologna, Italy
2 DIEGM, University of Udine, Via delle Scienze 208, 33100 Udine, Italy
Measured electron injection probabilities (PJN) into to the gate oxide of MOS structures  are presented for both liquid nitrogen and room temperature. For the first time PJN has been measured for total voltage drops (VTOT) in the substrate spanning from well below to well above the value corresponding to the Si-SiO2 barrier height (V*TOT=ΦB/q=3.15 V). In contrast to MOSFET data , here two different injection regimes can clearly be distinguished. For VTOT < V*TOT a regime 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 regime and therefore some insight will be given here by means of Monte Carlo simulations of the injection experiment. A simple analysis technique is developed, that explains the observed temperature dependence and injection regimes of PJN.
© EDP Sciences 1996