| 摘要 |
<P>PROBLEM TO BE SOLVED: To avoid degradation of quality of a device and transverse intensity in a case where a modified layer is formed inside a wafer by radiation of laser beam and the wafer is divided into individual devices with the modified layer as a start point. <P>SOLUTION: Laser beam 31a of a wavelength that penetrates a wafer W is condensed inside a division planned line L so that a modified layer R2 is formed which extends from a front surface side of the wafer W to the rear surface side. Etching gas or etching liquid is supplied to the wafer W so that the modified layer R2 is eroded and the wafer W is divided into individual devices. Since the modified layer is not crushed because it is eroded by etching, division into devices can be attained with no occurrence of micro powder. Thus, no micro powder sticks to the surface of the device to degrade quality of the device. Further, since the modified layer is removed by etching, degradation of transverse intensity of the device, which is caused by remaining of the modified layer, is prevented. <P>COPYRIGHT: (C)2013,JPO&INPIT |
