3D analytical modeling of surface potential, threshold voltage, and subthreshold swing in dual-material-gate (DMG) SOI FinFETs

Abstract

Here, we develop a 3D analytical model for potential in a lightly doped dual-material-gate FinFET in the subthreshold region. The model is based on the perimeter-weighted sum of a dual-material double-gate (DMDG) asymmetric MOSFET and a DMDG symmetric MOSFET. The potential model is used to determine the minimum surface potential needed to obtain the threshold voltage $$(V_{\mathrm{T}})$$(VT) and subthreshold swing (SS) by considering the source barrier changes in the leakiest channel path. The proposed model is capable of reducing the drain-induced barrier lowering (DIBL) as well as the hot carrier effects offered by this device. The impact of control gate ratio and work function difference between the two metal gates on $$V_{\mathrm{T}}$$VT and SS are also correctly established by the model. All model derivations are validated by comparing the results with technology computer-aided design (TCAD) simulation data.