Mobility Modeling in Advanced MOSFETs with Ultra-Thin Silicon Body under Stress

Authors

  • Viktor A. Sverdlov
  • Thomas Windbacher
  • Franz Schanovsky
  • Siegfried Selberherr

DOI:

https://doi.org/10.29292/jics.v4i2.298

Keywords:

mobility enhancement, strained silicon, stress dependent conductivity mass, non-parabolicity parameter, Monte Carlo simulation

Abstract

We use a two-band k·p model to describe the subband structure in strained silicon thin films. The model provides the dependence of the conductivity effective mass on strain and film thickness. The conductivity mass decreases along tensile stress in [110] direction applied to a (001) film. This conductivity mass decrease ensures the mobility enhancement in MOSFETs even with extremely thin silicon films. The two-band k·p model also describes the dependence of the non-parabolicity parameter on film thickness and strain. The influence of the subband structure modification on the mobility in advanced MOSFETs with strained ultra-thin silicon body is investigated. It is shown that an increase of subband non-parabolicity in thin films with strain reduces the mobility enhancement due to the conductivity mass modification, especially at higher strain values.

Additional Files

Published

2020-11-21