SiGe-channel n-MOSFET by germanium implantation

The first n-SiGe-channel MOSFETs fabricated using high-dose germanium implantation and solid-phase epitaxy are reported. The polysilicon-gate MOSFETs were fabricated in the same chip in which conventional polysilicon-gate n-MOSFETs were made and their electrical characteristics are compared. The SiGe-channel MOSFETs show some significantly better electrical characteristics as compared to the silicon-channel MOSFETs. For example, the SiGe MOSFETs show higher drain conductance in the triode region and higher transconductance overall. The threshold voltage of the SiGe MOSFET appears to be smaller and the carrier mobility in the channel appears to be higher.<>