Patent attributes
A method for manufacturing an SiC wafer from an SiC ingot includes a verifying step of applying a test laser beam to the SiC ingot in a predetermined area with the focal point of the test laser beam set inside the SiC ingot at a predetermined depth from the end surface of the SiC ingot. The test laser beam has a transmission wavelength to SiC, thereby forming a test separation layer inside the SiC ingot at the predetermined depth. The test separation layer has a test modified portion where SiC is decomposed into Si and C and test cracks extend from the test modified portion along a c-plane in the SiC ingot. Whether or not the test cracks have been properly formed is verified. When verifying, the power of the test laser beam is changed to set a proper power at which the test cracks are properly formed.
