‘Atomistic’ simulation of ultra-submicron MESFETs

Abstract

The effects of a discrete random dopant distribution on the MESFET characteristics were investigated using device simulation. The first three moments of the Boltzmann equation coupled to the Poisson equation are solved self-consistently. The model accounts for hot-electron effects, degeneracy and surface-states effects. The simulation indicates a nonuniform potential distribution in the active layer, which creates sharp variations in the electron density in that layer. It was also found that the drain electric current depends on the actual distribution of impurities. A comparison is made between the solutions of the transport equations for both dopant models (discrete and uniform) for MESFETs.