TWI739882B

An object of the present invention is to divide a wafer into chips while suppressing the occurrence of missing corners and unnecessary cracks. The invention relates to a wafer processing method, and more particularly to a wafer processing method having a surface where a device is respectively formed in each of regions divided by a plurality of intersecting cut scribe lines, including a surface protector component adhering step of adhering a surface protector component having highly rigid base material on the surface of the wafer; a modified layer forming step of forming a modified layer inside the wafer by irradiating the wafer with laser beam having permeability wavelength with respect to the wafer along the cut scribe line from the back side of the wafer after implementing surface protector component adhering step; a grinding step of thinning the wafer by grinding from the back side after performing the modified layer forming step. In the modified layer forming step or the grinding step, cracks are formed f