Patent ID: 7549560
Filing Date: 2009-06-23
Classification: B23K,B28D,H01L,Y10T

Abstract:
1. A method of dividing a wafer having function elements formed in areas sectioned by a plurality of first dividing lines formed parallel to one another and a plurality of second dividing lines that intersect with the first dividing lines and are formed parallel to one another, on the front surface thereof, along the first dividing lines and the second dividing lines, comprising: an internal deteriorated layer forming step for forming internal deteriorated layers in the inside of the wafer along the first dividing lines and the second dividing lines by applying a pulse laser beam capable of passing through the wafer along the first dividing lines and the second dividing lines; an intersection deteriorated layer forming step for forming intersection deteriorated layers that are thicker than the internal deteriorated layers by applying a pulse laser beam capable of passing through the wafer to intersection areas formed between the first dividing lines and the second dividing lines, a dividing step for dividing the wafer into individual chips along the first dividing lines and the second dividing lines by exerting external force along the first dividing lines and the second dividing lines of the wafer having the internal and intersectional deteriorated layers,