| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for processing a wafer which 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 processing a wafer 11 having a device region and an outer peripheral region surrounding the device region on a surface thereof comprises the steps of: positioning a condensing point of a pulse laser beam of a wavelength having permeability to the inside of the wafer corresponding to a division schedule line from a rear surface side of the wafer 11 and forming a modified layer 29 serving as a division start point inside the wafer 11 by irradiating the wafer with the pulse laser beam; 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. In the step of forming the modified layer, formation of a modified layer 29' in the outer peripheral region is inhibited by irradiating the wafer with a pulse laser beam whose output is lower than output of the pulse laser beam used to irradiate the rear surface 11b corresponding to the device region, on the rear surface 11b corresponding to the outer peripheral region of the wafer 11. |
