Tunnel field-effect transistor without gate-drain overlap

TLDR

Tunnel field‑effect transistors promise to replace MOSFETs by eliminating short‑channel effects and the sub‑threshold slope limit, yet their ambipolar nature and low on‑currents can limit switching speed. The authors extend the TFET design by shortening the gate structure, enabling a more flexible configuration. Simulations show the new design improves vertical nanowire TFETs by reducing ambipolarity, boosting switching speed, and lowering processing complexity.

Abstract

Tunnel field-effect transistors are promising successors of metal-oxide-semiconductor field-effect transistors because of the absence of short-channel effects and of a subthreshold-slope limit. However, the tunnel devices are ambipolar and, depending on device material properties, they may have low on-currents resulting in low switching speed. The authors have generalized the tunnel field-effect transistor configuration by allowing a shorter gate structure. The proposed device is especially attractive for vertical nanowire-based transistors. As illustrated with device simulations, the authors’ more flexible configuration allows of the reduction of ambipolar behavior, the increase of switching speed, and the decrease of processing complexity.