Effects of wave function penetration on gate capacitance modeling of nanoscale double gate MOSFETs

A study of dependence of wave function penetration effects on the gate capacitance of nanoscale DG MOSFETs on body-thickness, silicon surface orientation and the choice of high-kappa gate oxide material is presented. Gate capacitance increases when wave function penetration is incorporated. Wave function penetration effects on gate capacitance at low gate biases becomes more dominant with the scaling down of body-thickness. Relative error in gate capacitance due to the neglect of wave function penetration at low gate biases also depend on silicon surface orientation. However, at high gate biases penetration effects are independent of body-thickness and silicon surface orientation. Relative increase in gate capacitance due to wave function penetration is also higher for dielectric materials with smaller conduction band offset to silicon.