Physical modeling of Fermi-level effects for decanano device process simulations

Abstract

We report on a physically based Fermi-level modeling approach designed to be accurate and yet amenable to be implemented in a device-size process simulator. We use an atomistic kinetic Monte Carlo method in conjunction with a continuum treatment for carrier densities. The model includes: (i) charge reactions and electric bias according to the local Fermi-level; (ii) pairing and break-up reactions involving charged particles; (iii) clustering-related dopant deactivation; and (iv) Fermi level-dependent solubility. Degenerated statistics, band-gap narrowing, and damage-induced electrical compensation are also included. The parameters used for charged particles are in agreement with ab initio calculations and experimental results. This modeling scheme has proved to be very computationally efficient for realistic device-dimension process simulations. We present an illustrative set of simulation results for two common dopants, boron and arsenic, and discuss the potential of this approach for accurate process simulation of decanano CMOS devices.