3-D granular Monte Carlo simulation of silicon n-MOSFETs

摘要

A 3-D ensemble Monte Carlo (EMC) simulation with granular doping is implemented and simulations on a 50 nm channel length n-MOSFET are compared with results from 2- and 3-D simulations with continuous doping profiles. Granular simulations treat ionized acceptors in the channel discretely and the electron-ion interaction is calculated with a particle-particle-particle-mesh (P~3M) algorithm. Steady-state results for the electric field and electron velocities along the oxide interface are compared under strong inversion. Preliminary results indicate that 3-D Coulomb and granular effects in the channel have limited impact on transport in MOSFETs in the strong inversion case, but that the P~3M-EMC method shows promise for evaluating short-range effects including carrier-ion and carrier-carrier effects in subthreshold conditions where the impact of granularity should be larger.