| US 7,611,970 B2 | ||
| Wafer processing method | ||
| Toshiyuki Sakai, Tokyo (Japan) | ||
| Assigned to Disco Corporation, Tokyo (Japan) | ||
| Filed on Oct. 18, 2007, as Appl. No. 11/907,939. | ||
| Claims priority of application No. 2006-287897 (JP), filed on Oct. 23, 2006. | ||
| Prior Publication US 2008/0096368 A1, Apr. 24, 2008 | ||
| Int. Cl. H01L 21/322 (2006.01) | ||
| U.S. Cl. 438—473 [438/474; 438/799; 257/E21.317; 257/E21.318] | 2 Claims |
| 1. A water processing method for providing a gettering sink effect to a wafer having a plurality of streets which are formed
in a lattice pattern on the front surface of a substrate and devices which are formed in a plurality of areas sectioned by
the plurality of streets, comprising:
a grinding distortion layer removing step for removing grinding distortion produced on the rear surface of the substrate of
the wafer whose rear surface of the substrate has been ground to a predetermined thickness;
a gettering sink effect layer forming step for forming a gettering sink effect layer by applying a laser beam of a wavelength
having permeability for the substrate of the wafer which has undergone the grinding distortion layer removing step, with its
focal point set to the inside of the substrate to form a deteriorated layer in the inside of the substrate; and
a dividing step for dividing the wafer which has undergone the gettering sink effect layer forming step, into individual chips
along the streets.
|