Heteromaterial Gate Tunneling Field-Effect Transistor for High-Speed and Radio-Frequency Applications

Abstract

We propose a tunneling field-effect transistor (TFET) with a heteromaterial (HM)-gate not only for low standby power (LSTP) applications, which TFETs are genuinely suitable for, but also for highspeed performance by properly adjusting intrinsic gate capacitance (C-gg). As a result of simulations in this work, the HM-gate TFET showed better subthreshold characteristics (smaller S) at an appropriate threshold voltage (V-th) for LSTP applications, enhancing tunneling probability by modulating the difference in the metal workfunction (phi(m)) between the source-side gate (S-gate) and the drain-side gate (D-gate). Further, the C-gg of HM-gate TFET were extracted and compared against that of conventional TFETs having gates with various phi(m)'s. Since lower C-gg can be formed by high phi(m) in the D-gate, the HM-gate TFET has an excellent cut-off frequency (f(T)) and intrinsic delay time (tau) associated with the C-gg. We confirmed that the HM-gate TFET proposed in this work achieves superb performance for LSTP applications as well as high-frequency operations.