A semiempirical surface scattering model for quantum corrected Monte Carlo simulation of strained Si-nMOSFETs

A new semiempirical electron surface scattering model for full-band Monte Carlo (FBMC) simulations including a quantum corrected potential is presented for biaxially strained Si. The strain is assumed to be consistent with pseudomorphic growth on a relaxed SiGe buffer. The quantum potential model (Nguyen et al., 2005) used in our FBMC simulator (Grgec et al., 2004) accounts for size quantization effects in the inversion layer. In conjunction with the quantum potential model, the nonlocal surface scattering model for strained Si-nMOSFETs has been developed similar to the model implemented in our FBMC simulator for relaxed Si. For strained Si, some parameters are modeled as functions of Ge-content in the SiGe buffer in order to account for strain and to reproduce the measured low field mobility. The surface scattering rate is implemented in the FBMC simulator as a velocity randomizing scattering process (Hao et al., 1985) so that the efficient numerical integration of the low field mobility in equilibrium can be used (Jungemann and Meinerzhagen, 2003). The model has been calibrated and verified for Ge-contents between 0% and 30% and substrate doping levels between 10¹⁶cm^-3 and 5.5 · 10¹⁸cm^-3 by comparison to experimental data (Currie et al., 2001; Nayfeh et al., 2003). As a device example the WTMOS90-device (Antoniadis, 1999) with and without a strained Si channel has been simulated by our modified FBMC model.