Patent ID: 11901231
Assignee: DISCO CORPORATION
Field: Machine tools (Mechanical engineering)
Classification: CPC B  H | IPC B  H

Claim 0:
1. A separation method of a wafer by which the wafer having a first surface, a second surface on a side opposite to the first surface, and an outer circumferential surface that is located between the first surface and the second surface and that includes a curved part curved outward in a protruding manner is separated into two wafers, the separation method comprising:
a processing step of processing the wafer to remove part of the wafer along the curved part, wherein the entire outer circumferential surface is at least partially planarized between the first surface and the second surface in the processing step;
a separation origin forming step of, after the processing step, forming the separation origin inside the wafer by positioning a focal point of a laser beam with a wavelength having transmissibility with respect to the wafer inside the wafer and executing irradiation with the laser beam while the focal point and the wafer are relatively moved in such a manner that the focal point is kept inside the wafer; and
a separation step of separating the wafer into a first wafer having the first surface and a second wafer having the second surface from the separation origin by giving an external force after the separation origin forming step.