High Ge Content of SiGe Channel pMOSFETs on Si (110) Surfaces

The characteristics of Si
_0.2
Ge
_0.8
channel PFETs fabricated directly on Si (110) surfaces have been investigated. The saturation drain current and the hole mobility of a Si
_0.2
Ge
_0.8
(110) PFET are enhanced by 70% and by 80% for the <110> channel, as compared with that of a bulk Si (110) PFET. For comparison with a Si (100) PFET, a SiGe <110>/(110) PFET has ~ 200% hole mobility enhancement. The performance difference of the SiGe <110>/(110) and <100>/(110) PFET is about 2.7 times when considering mobility, and these effects are explained.