Fabrication, characterization, and physics of III–V heterojunction tunneling Field Effect Transistors (H-TFET) for steep sub-threshold swing

Abstract

This work demonstrates the steepest subthreshold swing (SS <; 60mV/decade) ever reported in a III-V Tunneling Field Effect Transistor (TFET) by using thin gate oxide, heterojunction engineering and high source doping. Owing to a lower source-to-channel tunnel barrier height, heterojunction III-V TFETs demonstrate steeper subthreshold swing (SS) at a given drain current (I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</sub> ) and improved drive current compared to the homojunction III-V TFETs. Electrical oxide thickness (EOT) scaling and increased source doping in tandem with tunnel barrier height reduction are shown to greatly improve the SS of the III-V TFETs and increase I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</sub> by more than 20X.