Patent ID: 7858902
Filing Date: 2010-12-28
Classification: B23K,B28D,H01L

Abstract:
1. A method of dividing a wafer having a plurality of streets which are formed in a lattice pattern on the front surface and devices which are formed in a plurality of areas sectioned by the plurality of streets, along the plurality of streets, comprising of: a deteriorated layer forming step for forming a deteriorated layer along the plurality of streets in the inside of the wafer by applying a laser beam of a wavelength having permeability for the wafer along the plurality of streets; an adhesive film mounting step for mounting an adhesive film for die bonding onto the rear surface of the wafer; a wafer supporting step for affixing the adhesive film side of the wafer onto a dicing tape mounted on an annular frame to support the wafer to the annular frame through the dicing tape; a first tape expanding step for dividing the wafer into individual devices along the streets which have undergone the deteriorated layer forming step, by expanding the dicing tape after the wafer supporting step; a dividing groove forming step for forming a dividing groove along the outer periphery of each individual device in the adhesive film, by applying a laser beam of a wavelength having absorptivity for the adhesive film through the spaces between adjacent devices in a state of the dicing tape having been expanded after carrying out the first tape expanding step; and a second tape expanding step for dividing the adhesive film along the dividing grooves by further expanding the dicing tape from the state of the first tape expanding step having been carried out after the dividing groove forming step.