| 摘要 |
PROBLEM TO BE SOLVED: To perform processing of forming a circular recessed portion on a back surface of a disk-like workpiece and leaving an annular projecting portion serving as a reinforcement portion in an outer periphery thereof, at a cost lower than that of a conventional method.SOLUTION: A processing method includes a step of cutting and removing a center portion of a back surface 1b of a disk-like workpiece 1 held by a holding table 20 by a cutting blade 33 to form a circular recessed portion 1E and an annular projecting portion 1F surrounding the circular recessed portion 1E. The step of forming the circular recessed portion E includes the steps of: allowing the cutting blade 33 rotating at a position at a predetermined distance to a center side of the workpiece 1 from an outer peripheral edge of the workpiece 1 to cut into the workpiece 1 from the back surface 1b side at a predetermined depth; and thereafter relatively moving the cutting blade 33 in a radial direction of the workpiece 1 while rotating the holding table 20 in a state in which the cutting blade 33 cuts into the workpiece 1. |
