Session 8A-4

Stress Engineering for High-k FETs: Mobility
and I_on Enhancements by Optimized Stress

 

Abstract

We present the first systematic study of uniaxial/biaxial stress effects on mobility and Ion enhancements in high-k n/pFETs. It is demonstrated for the first time that mobility enhancement of high-k nFETs by biaxial strain is greater than that of SiO2 nFETs in high Eeff, resulting in the better Ion improvement of high-k nFETs than SiO2 nFETs particularly in shorter-channel regime. The application of transverse tensile stress is crucial for improved n/pFETs.