Patent attributes
In a wafer processing method, the back side of the wafer is ground to reduce the thickness of the wafer to a predetermined thickness. A modified layer is formed by applying a laser beam to the wafer from the back side of the wafer along each division line with the focal point of the laser beam set inside the wafer. The wafer is mounted on a reinforcing sheet having an insulating function on the back side of the wafer and a dicing tape is attached to the reinforcing sheet. The peripheral portion of the dicing tape is supported by an annular frame. The wafer is heated, which also heats the reinforcing sheet, thereby hardening the reinforcing sheet. An external force is applied to the wafer to divide the wafer into individual devices along each division line and to also break the reinforcing sheet along the individual devices.