| 摘要 |
PROBLEM TO BE SOLVED: To provide a wafer processing method of processing a wafer of silicon on which plural devices are formed while compartmented by plural parting scheduled lines, the method suppressing transmitted light from damaging the devices on the surface of the wafer when a reformed layer is formed in the wafer by irradiating silicon wafer with a pulse laser beam having a wavelength set in the range from 1300 to 1400 nm.SOLUTION: When the wavelength of a pulse laser beam having transmissivity to a wafer is set in the range from 1300 nm to 1400 nm, the convergence point of the pulse laser beam is positioned in the wafer, the pulse laser beam is applied from the back surface of the wafer to form a reformed layer 19, and the wafer is parted with the reformed layer set as a parting start point by applying external force to the wafer, a first protection member 23 through which the pulse laser beam is transmitted is disposed on the upper surface of the wafer which is irradiated with the pulse laser beam when the reformed layer is formed.SELECTED DRAWING: Figure 6 |
