Patent ID: 8609497

Claim:
A method of fabricating a semiconductor device, comprising: forming first and second gate structures over first and second regions of a substrate, respectively; forming spacers on sidewalls of the first and second gate structures, the spacers being formed of a first material that is doped; forming a capping layer over the first and second gate structures, the capping layer being formed of a second material different from the first material, wherein the second material is undoped; forming a protection layer over the second region to protect the second gate structure; removing the capping layer over the first gate structure; removing the protection layer over the second region; epitaxially (epi) growing a semiconductor material on exposed portions of the substrate in the first region; and removing the capping layer over the second gate structure by an etching process that exhibits an etching selectivity of the second material that is undoped to the first material that is doped, wherein removing the capping layer over the second gate structure by the etching process that exhibits the etching selectivity of the second material that is undoped to the first material that is doped occurs prior to forming another capping layer over the second gate structure, the another capping layer being formed of the second material.