Patent ID: 8497189
Filing Date: 2013-07-30
Classification: B23K,B28D,H01L

Abstract:
1. A processing method for a wafer which has, on a front face thereof, a device region in which a device is formed in each of regions partitioned by a plurality of scheduled division lines and an outer peripheral region which surrounds the device region, the processing method comprising: a reflecting film forming step of forming a reflecting film of a predetermined width from the outermost periphery of the wafer on a rear face of the wafer corresponding to the outer peripheral region; a modified layer forming step of holding, after the reflecting film forming step is carried out, the front face side of the wafer by a chuck table, positioning a focal point of a pulsed laser beam of a wavelength having permeability through the wafer in the inside of the wafer corresponding to the scheduled division lines and irradiating the pulsed laser beam from the rear face side of the wafer to form modified layers individually serving as a start point of division along the scheduled division lines in the inside of the wafer; and a transporting step of taking out, after the modified layer forming step is carried out, the wafer from the chuck table and transporting the wafer to a next step.