US 12,227,875 B2
SiC wafer and SiC epitaxial wafer
Shunsuke Noguchi, Tokyo (JP)
Assigned to Resonac Corporation, Tokyo (JP)
Filed by Resonac Corporation, Tokyo (JP)
Filed on Dec. 18, 2023, as Appl. No. 18/543,359.
Claims priority of application No. 2022-203405 (JP), filed on Dec. 20, 2022.
Prior Publication US 2024/0200227 A1, Jun. 20, 2024
Int. Cl. C30B 29/36 (2006.01); B32B 3/02 (2006.01)
CPC C30B 29/36 (2013.01) [B32B 3/02 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A SiC wafer in which a crystal surface has an offset angle of 0.5° or more and 10° or less in a first direction with respect to a surface of the SiC wafer, and dislocations are confirmed when a first measurement point is measured using X-ray reflection topography with (3-3016) as a diffraction surface,
wherein the first measurement point is a point shifted by a length of ½ of a radius of the SiC wafer in the first direction from the center of a measurement region that is 5 mm or more inside from the outer circumferential end of the SiC wafer,
wherein the dislocations include first dislocations having an aspect ratio of 5 or more and second dislocations having an aspect ratio of less than 3, where the aspect ratio is obtained by dividing a long axis length of a rectangle that circumscribes the dislocation and has the smallest area by a short axis length, and
wherein, at the first measurement point, the density of the first dislocations is higher than the density of the second dislocations.