Dual metal drain Ge‐source dopingless TFET with enhanced turn‐ON steep subthreshold swing and high ON‐current

Abstract

A novel dopingless Ge-source dual metal drain double gate tunnel field effect transistor is presented with the help of work function engineering. Proposed device makes use of the dopingless concept, charge plasma for carrier doping concentration below the drain/source region that permits dynamic configuration by choosing suitable work function for drain/source metal electrode. In the proposed device, the n + drain region is divided into two parts of low and high work function. The work function of the metal nearest to the drain–channel junction is relatively higher than the other metal for creating a potential barrier for restricting the tunnelling of holes when the negative gate voltage is applied. By using low energy bandgap Ge material, the tunnelling probability and drive current of the device are increased. The proposed device offers high I ON/I OFF ratio (∼1013), smaller point subthreshold swing (SS) (∼31 mV/decade), average SS (∼43 mV/decade).