Numerical Study on Ballistic n+–i–n+ Diode by Monte Carlo Simulation: Influence of Energy Relaxation of Hot Electrons in Drain Region on Ballistic Transport

Abstract

We have investigated the effects of elastic and inelastic scatterings in the drain region on hot carrier transport in a ballistic silicon n+–i–n+ diode by the semiclassical Monte Carlo simulation. In a ballistic n+–i–n+ diode, elastic scattering such as that of intravalley acoustic phonons and ionized impurity scattering cause the backward flow of hot electrons from the drain into the channel and severely degrades the mean velocity in the channel region and steady-state current. On the other hand, inelastic scattering such as that of intervalley optical phonons suppresses the backward flow caused by elastic scattering because the kinetic energy of hot electons is lost in the scattering. That is, inelastic scattering increases the ballisticity of the device. We conclude that the scattering and energy relaxation of hot electrons in the drain region seriously influence the carrier transport in the ballistic n+–i–n+ diode.