Patent ID: 9543189
Date: 2017-01-10
CPC Classifications: H01L

Claim:
1. A method of processing a laminated wafer in which a first wafer is laminated on a second wafer, the method comprising: a laminated wafer forming step of forming the laminated wafer by laminating the first wafer on the second wafer via an insulating film selected from the group of an oxide film, a nitride film and an oxynitride film; a modified layer forming step of forming a modified layer which is not exposed on a surface of the first wafer within the first wafer by positioning a focusing point of a laser beam within the first wafer and moving the first wafer in a horizontal direction relative to the focusing point while applying the laser beam, the modified layer forming step being performed before or after the laminated wafer forming step is performed; and a separating step of separating only part of the first wafer from the laminated wafer with the modified layer as a boundary, a remaining portion of the first wafer adjacent the insulating film having a predetermined thickness, the separating step being performed after the laminated wafer forming step and the modified layer forming step are performed, wherein the focusing point moves relative to the first wafer to describe a spiral locus within a plane.