Abstract: Techniques are provided herein to use a chemical mechanical polishing (CMP) process to polish carbon hard mask (CHM) for a variety of useful semiconductor fabrication applications. In one example, a CMP process that uses a silica-based slurry is used to polish CHM formed over gate trenches of different widths, such that the CHM can recess to substantially the same height within the gate trenches of different widths. In another example, CHM may be deposited over groups of fins or a backbone structure and polished using a CMP process with a silica-based slurry to ensure a planar top surface of CHM over the groups of fins or backbone structure.

Abstract: A multi-platen, multi-slurry chemical mechanical polishing method comprises providing a substrate having a surface that includes at least one nitride structure and an oxide layer atop the nitride structure, performing a first CMP process on the substrate using a first platen with a silica based slurry to remove a bulk portion of the oxide layer without exposing the nitride structure, performing a second CMP process on the substrate using a second platen with a ceria based slurry to remove a residual portion of the oxide layer and to expose at least a portion of the nitride structure, and performing a third CMP process on the substrate using the first platen with a silica based slurry to remove at least one defect caused by the ceria based slurry.

Abstract: A multi-platen, multi-slurry chemical mechanical polishing method comprises providing a substrate having a surface that includes at least one nitride structure and an oxide layer atop the nitride structure, performing a first CMP process on the substrate using a first platen with a silica based slurry to remove a bulk portion of the oxide layer without exposing the nitride structure, performing a second CMP process on the substrate using a second platen with a ceria based slurry to remove a residual portion of the oxide layer and to expose at least a portion of the nitride structure, and performing a third CMP process on the substrate using the first platen with a silica based slurry to remove at least one defect caused by the ceria based slurry.