| 摘要 |
PROBLEM TO BE SOLVED: To provide a processing method of a wafer capable of determining whether a formation condition of a modified layer is appropriate, before dividing the wafer.SOLUTION: The processing method includes: a protective member arranging step of arranging a protective member (21) at the side of a front face (11a) of a wafer (11); a holding step of holding the protective member with a chuck table (10); a reference width setting step of setting a reference width of a modified layer (23) to be formed on the wafer; a modified layer forming step of forming the modified layer by irradiating the wafer held by the chuck table from the side of a rear face (11b) with a laser beam (40) along a predetermined dividing line (17) while focusing (42) the inside of the wafer; and a crack determining step of determining generation of a crack (25) extending from the modified layer to the front face of the wafer in the case where the modified layer of the wafer held by the chuck table is imaged from the rear face side of the wafer by an infrared camera (14) and a width of the imaged modified layer is wider than the reference width. |
