Method of semiconductor fabrication incorporating disposable spacer into elevated source/drain processing

A semiconductor fabrication process comprising:

• forming a gate electrode overlying a substrate;
• forming an oxide liner on sidewalls of the gate electrode;
• forming an offset spacer of silicon nitride adjacent the oxide liner;
• forming an intermediate liner of silicon oxide adjacent the offset spacer;
• forming a disposable spacer of silicon nitride adjacent the intermediate liner;
• forming an elevated source/drain overlying the substrate and displaced laterally from sidewalls of the gate electrode by the disposable spacer;
• following forming the elevated source/drain removing the intermediate oxide liner and the disposable spacer to expose the upper surface of the substrate and implanting halo and extension implants into the exposed substrate;
• and
• following performing the halo and extension implants, forming a replacement intermediate oxide liner and a replacement spacer located substantially where the original intermediate oxide liner and disposable spacer were located.

A semiconductor fabrication process, comprising:

• forming a gate electrode overlying a substrate;
• forming an oxide liner on sidewalls of the gate electrode;
• forming a silicon nitride offset spacer adjacent the oxide liner;
• forming an intermediate liner of silicon oxide adjacent the offset spacer;
• forming a disposable silicon nitride spacer adjacent the offset spacer;
• forming an elevated source/drain structure overlying regions of the substrate not protected by the gate electrode or the disposable spacer;
• without removing the offset spacer, removing the disposable spacer and the intermediate oxide liner to expose the substrate proximal to the gate electrode;
• implanting an impurity distribution into the exposed substrate proximal the gate electrode;
• forming a replacement intermediate oxide liner and a replacement spacer substantially where the intermediate liner and the disposable spacer existed;
• and
• after forming the replacement spacer, performing a source/drain implant to introduce a source/drain impurity distribution into the elevated source drain.