| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for processing a wafer which has a reflection film on a rear surface thereof and does not break along a modified layer when carrying out the wafer from a laser processing device and transporting it to a next step.SOLUTION: A method for forming a wafer comprises the steps of: forming a step part 27 of a prescribed width lower than a rear surface 11b by a prescribed height on the rear surface 11b corresponding to an outer peripheral region of a wafer 11; holding the surface side of the wafer 11 by a chuck table, positioning a condensing point of a pulse laser beam 69 having a wavelength permeable through the wafer to the inside of the wafer 11 corresponding to a division schedule line from a rear surface side of the wafer 11, and forming a modified layer serving as a division start point inside the wafer 11 along the division schedule line by irradiating the wafer with the pulse laser beam 69 after performing the step of forming the step part; and carrying out the wafer 11 from the chuck table and transporting it to a next step after performing the step of forming the modified layer. |
