Evidence for suppressed short-channel effects in deep submicron dual-material gate (DMG) partially depleted SOI MOSFETs – A two-dimensional analytical approach

Abstract

Short-channel effects in a dual-material gate partially depleted (DMG-PD) silicon-on-insulator (SOI) MOSFET are studied by developing a 2-D analytical model for the surface potential variation along the channel. The model includes the calculation of the surface potential, electric field along the channel and threshold voltage using the minimum surface potential. The model takes into account the effects of body doping concentration, gate oxide, buried oxide and silicon film thickness, lengths of the gate metals and their work functions, applied drain and substrate biases. It is seen that short channel effects in this structure are suppressed because of the perceivable step in the surface potential profile, which screens the drain potential. It is also seen that the model predicts a threshold voltage roll-up as the channel length is reduced. The results predicted by the model are compared with those obtained by two-dimensional simulation to verify the accuracy of the proposed analytical model.