Self-forces in 3D finite element Monte Carlo simulations of a 10.7 nm gate length SOI FinFET

Abstract

Particle-mesh coupling in ensemble Monte Carlo simulations of semiconductor devices results in unphysical self-forces when using unstructured meshes to describe the device geometry. We develop a correction to the driving electric field and show that self-forces can be virtually eliminated on a finite element mesh at a small additional computational cost. The developed methodology is included into a self-consistent 3D finite element Monte Carlo device simulator. We simulate an isolated particle and show the kinetic energy conservation down to a magnitude of 10-10 meV. The methodology is applied to a 10.7 nm gate length FinFET simulation and we find that for a large enough ensemble of particles, the impact of self-forces on the final ID-VG is almost negligible.