Intrinsic Reliability improvement in Biaxially Strained SiGe p-MOSFETs

Abstract

In this letter we not only show improvement in the performance but also in the reliability of 30nm thick biaxially strained SiGe (20%Ge) channel on Si p-MOSFETs. Compared to Si channel, strained SiGe channel allows larger hole mobility ({\mu}h) in the transport direction and alleviates charge flow towards the gate oxide. {\mu}h enhancement by 40% in SiGe and 100% in Si-cap SiGe is observed compared to the Si hole universal mobility. A ~40% reduction in NBTI degradation, gate leakage and flicker noise (1/f) is observed which is attributed to a 4% increase in the hole-oxide barrier height ({\phi}) in SiGe. Similar field acceleration factor ({\Gamma}) for threshold voltage shift ({\Delta}VT) and increase in noise ({\Delta}SVG) in Si and SiGe suggests identical degradation mechanisms.