Quantum mechanical effects on the threshold voltage of nanoscale dual channel strained Si/strained Si_(1-y)Ge_y/relaxed Si _(1-x)Ge_x MOSFETs

摘要

In this paper, a new analytical model derived for the threshold voltage, V_(th) of dual channel strained Si/Strained Si_(1-y)Ge _y/relaxed Si_(1-x)Ge_x pMOSFETs, including the Quantum Mechanical Effects (QMEs) is presented. The goal of this model is to investigate the impact of QMEs on the magnitude of the oxide thickness, flatband voltage and threshold voltage for 45 nm channel length. Under QMEs, the carrier charges in extended states and quantized states contribute to the increases in the threshold voltage. Our model includes the effects of strain, channel length, oxide thickness, and also substrate doping concentration. The quantum confinement and carrier quantization on the shift of V_(th) are briefly explained. In addition, it is demonstrated that both the electron affinity and bandgap of strained Si_(1-y)Ge_y and relaxed Si _(1-x)Ge_x contribute to the changes in threshold voltage. Our analytical results offer good accuracy when compared to 2D Atlas simulated results and data available in the literature.