IGFET hot electron emission model

Abstract

A new model for hot electron emission into the oxide layer of IGFETs is presented. When IGFETs operate under high gate and drain bias conditions, electrons are accelerated by the high drain field and injected into the oxide layer at a certain probability. The present model takes into account the following: (1) the energy dependence of hot electron scattering probability, (2) the three-dimensional angle at which electrons are injected into the oxide layer, (3) the quantum effect at the SiSiO 2 interface that gives the reflection probability, and (4) the scattering and reaching probabilities without energy loss. The total emission current is obtained by a five-fold integral over the energy, position and solid angle elements. The current thus predicted is expected to be two or three orders of magnitude smaller than that from Phillips' model previously proposed for IGFET emission current and hence closer to experimintal data. The present model can give the position dependence of emitted current and is suitable for incorporation into two-dimensional numerical analysis.