Chemical mechanical polishing of silicon carbide comprising surfaces

A method of chemically-mechanically polishing, comprising:

• providing a substrate having a silicon carbide comprising surface,
• chemically-mechanically polishing said silicon carbide comprising surface with a chemical-mechanical polishing slurry composition, said slurry composition comprising:
• an aqueous liquid carrier;
• an oxidizing agent comprising a transition metal compound;
• a plurality of particles having at least a soft surface portion comprising a transition metal compound layer that provides a Mohs hardness <6, said transition metal compound layer comprising both an insoluble Mn+3 compound and an insoluble Mn+4 compound;
• contacting said silicon carbide comprising surface with said slurry composition, and
• moving said slurry composition relative to said silicon carbide comprising surface, wherein at least a portion of said silicon carbide comprising surface is removed.

A method of chemically-mechanically polishing a substrate having a silicon carbide comprising surface, comprising:

• providing a chemical-mechanical polishing slurry composition, comprising:
• a liquid carrier,
• a plurality of particles having at least a soft surface portion, said soft surface portion comprising a transition metal compound coating that provides a Mohs hardness ≦6 or a Knoop Hardness less than 900 Kg/mm2, and
• an oxidizing agent in a concentration from 0.02M to 0.4 M comprising a first transition metal compound,
• wherein said oxidizing agent catalytically breaks down within said slurry composition to form at least one of (i) an insoluble compound that provides at least a portion of said transition metal compound coating and (ii) particles consisting of said insoluble compound, and
• contacting said silicon carbide comprising surface with said slurry composition;
• and
• moving said slurry composition relative to said silicon carbide comprising surface, wherein at least a portion of said silicon carbide comprising surface is removed,
• wherein said silicon carbide comprising surface consists essentially of a silicon carbide surface, and a polishing rate for said silicon carbide surface is ≧200 nm/hr.