Potential-based threshold voltage and subthreshold swing models for junctionless double-gate metal-oxide-semiconductor field-effect transistor with dual-material gate

On the basis of quasi-two-dimensional solution of Poisson's equation, an analytical threshold voltage model for junctionless dual-material double-gate (JLDMDG) metal-oxide-semiconductor field-effect transistor (MOSFET) is developed for the first time. The advantages of JLDMDG MOSFET are proved by comparing the central electrostatic potential and electric field distribution with those of junctionless single-material double-gate (JLSMDG) MOSFET. The proposed model explicitly shows how the device parameters (such as the silicon thickness, oxide thickness, and doping concentration) affect the threshold voltage. In addition, the variations of threshold voltage roll-off, drain-induced barrier lowering (DIBL), and subthreshold swing with the channel length are investigated. It is proved that the device performance for JLDMDG MOSFET can be changed flexibly by adjusting the length ratios of control gate and screen gate. The model is verified by comparing its calculated results with those obtained from three-dimensional numerical device simulator ISE. Copyright (c) 2015John Wiley & Sons, Ltd.