Two-Dimensional Materials for Future Electronics

Abstract

As transistor lengths are scaled down, the transistor gate controllability becomes weaker owing to pronounced source-drain tunneling. Hence, the transistor body thickness needs to be reduced to ensure efficient electrostatic control. New materials such as “ultra-thin” 2D semiconducting materials have attracted attention. In this short talk, I would like to provide our analysis and arguments on the possibility to scale the device dimension, for example down to 1nm technology node or beyond, using transition metal dichalcogenides (TMD) semiconductors. There are many challenges ahead. In this presentation, I will discuss several advancements we and collaborators have achieved recently. (1) We discovered that hydroxide vapor phase epitaxy enables the growth of WS2 monolayers with a significantly lower density of structural defects, which make the electron mobility peaked at ~ 200 cm 2 /Vs. (2) Ultrahigh-k dielectrics can be applied onto short-channel (30 nm) 2D monolayer transistors to greatly lower the subthreshold swing (down to 70 mV dec -1 ) with an ON/OFF current ratio up to 10^7 . (3) Semimetal is a feasible n-type contact metal to TMD monolayers that can achieve almost zero Schottky Barrier height.