In order to develop a low-cost alternative to diamond-based polishing slurries for SiC, mechanical polishing of 3C-SiC films using SiC-based slurries was studied, and an optimized polishing recipe was developed. The relationship among applied force, particle size, and slurry solid contents on the roughness reduction rate of as-deposited 3C-SiC films was investigated. A response surface methodology statistical approach was used to determine the functional relationship between the aforementioned parameters in order to optimize the polishing recipe. The optimized polishing recipe reduces the surface roughness from approximately 400 to 40 Angstrom, while only removing 1000 Angstrom. of the film. This recipe has been successfully used as part of a surface treatment process for homoepitaxial growth of low defect density 3C-SiC films on 3C-SiC substrates.