Patent ID: 9391148
Filing Date: 2016-07-12
CPC Classification: C09K,C30B,H01L

Claim Text:
1. A single crystal SiC substrate having a CMP-treated polished surface, wherein the single crystal SiC substrate has 5 or fewer lattice defects, which have a width of 30 nm or more in a direction parallel to the polished surface and a length of 50 nm or more in a direction perpendicular to the polished surface, as counted within a depth of 100 nm from the polished surface in a direction perpendicular to the polished surface and a length of 10 μm in a direction parallel to the polished surface when observed in cross-section using a transmission electron microscope under the 00L reflection or the h-h0 reflection, where L and h are each an integer other than 0; and wherein the CMP treatment is carried out using a polishing slurry containing manganese oxide particles and manganate ions; the manganate ion concentration in the polishing slurry is from 0.5 to 40 mass %, and the manganese oxide particles content is from 1.0 to 35 mass %; and the molar ratio of manganate ion to manganese oxide in the polishing slurry is ⅕ or higher.