abstract |
A semiconductor device includes a gate stack over a substrate. The semiconductor device further includes an interlayer dielectric (ILD) at least partially enclosing the gate stack. The ILD includes a first portion doped with an oxygen-containing material. The ILD further includes a second portion doped with a large species material, wherein the second portion includes a first sidewall substantially perpendicular to a top surface of the substrate, and the second portion includes a second sidewall having a positive angle with respect to the first sidewall. |