Drain Current Model Including Velocity Saturation for Symmetric Double-Gate MOSFETs

A drain current model is developed for a symmetrically driven undoped (or lightly doped) symmetric double-gate MOSFET (SDGFET) under the drift-diffusion transport mechanism, with velocity saturation effects being included as an integral part of the model derivation. Velocity saturation effects are modeled by using the Caughey-Thomas engineering model with exponent n = 2. I_d-V_d, I_d-V_g, g_m -V_g, and g_DS-V_d comparisons are made with 2-D device simulation results, and a very good match is found all the way from subthreshold to strong inversion. Gummel symmetry compliance is also shown.