Contact etch stop layers of a field effect transistor

摘要

An exemplary structure for a field effect transistor according to at least one embodiment comprises a substrate comprising a surface; a gate structure comprising sidewalls and a top surface over the substrate; a spacer adjacent to the sidewalls of the gate structure; a first contact etch stop layer over the spacer and extending along the surface of the substrate; an interlayer dielectric layer adjacent to the first contact etch stop layer, wherein a top surface of the interlayer dielectric layer is coplanar with the top surface of the gate structure; and a second contact etch stop layer over the top surface of the gate structure.