Scattering from Body Thickness Fluctuations in Double Gate MOSFETs: An ab initio Monte Carlo Simulation Study

This paper describes the impact of surface roughness related body thickness fluctuations on the mobility in double gate MOSFETs. The analysis combines 3D drift diffusion simulations with density gradient quantum corrections and ensemble Monte Carlo simulations, which include, in an ab initio fashion, the additional scattering associated with the variation in the quantum mechanical confinement along the channel. Results for a range of devices with varying silicon thicknesses and both smooth and rough interfaces are presented in order to demonstrate the impact of this additional scattering mechanism on the mobility in the channel.