CMOS transistor having different PMOS and NMOS gate electrode structures and method of fabrication thereof

摘要

In a CMOS semiconductor device using a silicon germanium gate and a method of fabricating the same, a gate insulating layer, a conductive electrode layer that is a seed layer, a silicon germanium electrode layer, and an amorphous conductive electrode layer are sequentially formed on a semiconductor substrate. A photolithographic process is then carried out to remove the silicon germanium electrode layer in the NMOS region, so that the silicon germanium layer is formed only in the PMOS region and is not formed in the NMOS region.