| US 7,507,639 B2 | ||
| Wafer dividing method | ||
| Masaru Nakamura, Tokyo (Japan) | ||
| Assigned to Disco Corporation, Tokyo (Japan) | ||
| Filed on Dec. 04, 2006, as Appl. No. 11/633,056. | ||
| Claims priority of application No. 2005-352435 (JP), filed on Dec. 06, 2005. | ||
| Prior Publication US 2007/0128767 A1, Jun. 07, 2007 | ||
| Int. Cl. H01L 21/78 (2006.01) | ||
| U.S. Cl. 438—463 [438/464; 257/E21.599] | 2 Claims |
| 1. A method of dividing a wafer having a plurality of dividing lines 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 dividing lines, into individual chips along
the dividing lines, comprising:
a deteriorated layer forming step for forming a deteriorated layer in the inside of the wafer along the dividing lines by
applying a laser beam of a wavelength having permeability for the wafer along the dividing lines;
a wafer supporting step for putting the rear surface of the wafer on the surface of an adhesive tape which is affixed to an
annular frame and whose adhesive strength is reduced by applying ultraviolet radiation thereto after the deteriorated layer
forming step; and
a chips-spacing forming step for reducing the adhesive strength of the adhesive tape and shrinking a shrink area between the
inner periphery of the annular frame and the area to which the wafer has been affixed, of the adhesive tape by applying ultraviolet
radiation to the adhesive tape to which the wafer having the deteriorated layers along the dividing lines has affixed so as
to divide the wafer into individual chips along the dividing lines where the deteriorated layer has been formed and widen
the space between adjacent chips.
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