The present invention relates generally to semiconductor devices, and more particularly, to a structure and method of forming a complementary metal-oxide semiconductor (CMOS) with dual strained channels.
In some FET devices, the introduction of strain (e.g., compressive or tensile) to the channel region of the FET may be used to improve carrier mobility, which may subsequently increase FET performance. Compressive strain may be used with p-channel PFETs to improve hole mobility and tensile strain may be used with NFETs to improve electron mobility. However, forming a semiconductor layer with a compressive strain and a semiconductor layer with a tensile strain on the same wafer is challenging.