High Performance pMOSFETs Using Si/Si<inf>1-x</inf>Ge<inf>x</inf>/Si Quantum Wells with High-k/Metal Gate Stacks and Additive Uniaxial Strain for 22 nm Technology Node

Abstract

We demonstrate for the first time that both SiGe and Ge channel with high-k/metal gate stack pMOSFETs show similar uniaxial stress enhanced drive current as Si which is expected from k.p calculations. We also demonstrate experimentally that pMOSFETs with strained quantum wells (QW) in the Si-Ge system exhibited high performance and low off-state leakage comparable to optimized gate stacks on Si. These results significantly hasten the feasibility of realizing SiGe or Ge channel pMOSFETs for 22 nm and beyond.