Method to reduce threshold voltage (Vt) in silicon germanium (SiGe), high-k dielectric-metal gate, p-type metal oxide semiconductor field effect transistors

摘要

Disclosed are embodiments of a p-type, silicon germanium (SiGe), high-k dielectric-metal gate, metal oxide semiconductor field effect transistor (PFET) having an optimal threshold voltage (Vt), a complementary metal oxide semiconductor (CMOS) device that includes the PFET and methods of forming both the PFET alone and the CMOS device. The embodiments incorporate negatively charged ions (e.g., fluorine (F), chlorine (Cl), bromine (Br), iodine (I), etc.) into the high-k gate dielectric material of the PFET only so as to selectively adjust the negative Vt of the PFET (i.e., so as to reduce the negative Vt of the PFET).