Source-drain symmetry in unified regional MOSFET model

This letter investigates major sources of asymmetry in a MOSFET compact model by comparing source versus bulk reference in the drain current, effective field, and effective mobility equations. Contrary to the general belief that a regional threshold voltage (V_t)-based model may pose a symmetry problem, we demonstrate that even with the simple source-extrapolated V_t-based model, it can be symmetric if the drain current and the effective transverse field are derived with bulk as the reference, and the lateral-field effective mobility are properly modeled.