| 摘要 |
PROBLEM TO BE SOLVED: To provide a wafer processing method by which a wafer can be divided along dividing lines while preventing a decrease in the transverse intensity of devices and damage to the devices due to impact force.SOLUTION: A wafer processing method in which a wafer on the surface of which a plurality of devices are formed is divided along a plurality of dividing lines for separating the devices from one another, comprises: a modified-layer formation step in which the point at which a laser beam of wavelength transmissive to the wafer is focused is emitted along the dividing lines while being located inside from the rear surface of the wafer, and a modified layer for propagating a crack toward the surface of the wafer is formed along the dividing lines; an ablation processing step in which a modified layer formed along the dividing lines is removed by performing an ablation process in which a laser beam of wavelength absorptive with respective to the wafer is emitted along the dividing lines from the rear surface of the wafer; and a wafer dividing step in which the wafer is divided into individual devices by cracks formed along the dividing lines. |
