Semiconductor device and method for manufacturing the same

摘要

A semiconductor device suitable for the miniaturization and comprising properly controlled Si/SiGe gate electrode comprises an insulator formed on a semiconductor substrate, a first gate electrode formed on the insulator and including silicon-germanium, wherein a germanium concentration is higher near an interface to the insulator and lower in a surface side opposite to the insulator, and a second gate electrode formed on the insulator and including silicon-germanium, wherein a germanium concentration is substantially uniform and an n-type dopant of a concentration of above 6x10²⁰ atoms/cm³ is contained.