Temperature dependent model for threshold voltage and subthreshold slope of strained-Si channel MOSFETs with a polysilicon gate

•Temperature dependent model for threshold voltage and subthreshold slope for strained Si MOSFETs was developed.•Model was validated with reported experimental results.•Threshold voltage drops with increasing temperature while subthreshold slope increases.•Channel strain reduces threshold voltage and affects subthreshold slope weakly.

We present a temperature dependent model for the threshold voltage Vt and subthreshold slope S of strained-Si channel MOSFETs and validate it with reported experimental data for a wide range of temperature, channel doping concentration, oxide thickness and strain value. Such model includes the effect of lattice strain on material, temperature dependent effective mass of carriers, interface-trapped charge density and bandgap narrowing due to heavy channel doping. Also considered are polydepletion effects, carrier localization effect in the ultra-thin channel and quantum-mechanical effects. Our investigation reveals that the threshold voltage reduces linearly with increasing temperature whereas the subthreshold slope increases. In addition Vt is found to be sensitive to strain while S is weakly dependent on strain. Moreover, the channel doping concentration influences both Vt and S, and also the rate of change of Vt with temperature. Furthermore, S decreases for a lightly doped channel particularly at lower temperatures.