Two-Dimensional Numerical Simulation of Bottom-Gate and Dual-Gate Amorphous In-Ga-Zn-O MESFETs

In this letter, the electrical properties of bottom-gate and dual gate (DG) amorphous In-Ga-Zn-O (a-IGZO) metal-semiconductor field-effect transistors (MESFETs) are studied by a 2-D numerical simulation. A subgap density of state model is proposed and used in the simulation. The bottom gate MESFET shows field-effect mobility (mu(FE)) of 9 cm (2)/V s, threshold voltage (V-th) of -6.3 V, and subthreshold swing of 0.12 V/decade. The DG a-IGZO MESFET structure is suggested to effectively increase the device operational current (I-on).