Monte Carlo Simulations of Ge Implant Free Quantum Well FETs - The Role of Substrate and Channel Orientation

Previous simulation studies of a 20nm gate length IFQW device have considered the impact of the spacer separating the gate from the raised source and drain regions. In this work the study is extended to consider how interface roughness from the gate stack, the introduction of biaxial compressive strain from a Si_0.2Ge_0.8 substrate and transition to a (110) surface orientation from the standard (001) can influence performance in terms of low field mobility and on current. Full band Monte Carlo transport simulations are used, with a 6 band k.p bandstructure and scattering from inelastic acoustic (IAP), optical (IOP) and SO phonons, ionized impurities and surface roughness (SR), calibrated to experimental data.