US Patent 10573505 SiC wafer producing method

A method for producing a wafer from an ingot of single crystal SiC includes an end surface planarizing step of planarizing an end surface of the ingot, a separation layer forming step of setting a focal point of a laser beam having a transmission wavelength to single crystal SiC inside the ingot at a predetermined depth from the end surface of the ingot, the predetermined depth corresponding to the thickness of the wafer to be produced, and next applying the laser beam to the ingot to thereby form a separation layer for separating the wafer from the ingot, a hard plate providing step of providing a hard plate through an adhesive on the end surface of the ingot in which the separation layer has been formed, and a separating step of separating the wafer with the hard plate from the ingot along the separation layer.