Surface roughness induced device variability: 3D ab initio Monte Carlo simulation study

It is expected that published results from drift diffusion simulation of oxide thickness fluctuations in nano-scale devices underestimates the true intrinsic device parameter variation by neglecting local variations in surface roughness scattering. We present initial results from 3D ‘bulk’ Monte Carlo simulation including an ab initio treatment of surface roughness scattering capable of capturing such transport variation. The scattering is included directly through the real space propagation of carriers in the fluctuating potential associated with a randomly generated interface. We apply this approach to simulate inversion layer mobility in order to validate the model before its possible application in device variability simulations. Qualitative agreement is found with universal mobility data and avenues for possible calibration of surface and simulation parameters are highlighted.