Wafer grinding method

Abstract

A wafer grinding method for grinding the surface to be ground of a wafer having an arcuatedly chamfered outer peripheral surface, comprising an outer peripheral portion removal step for removing the outer peripheral portion of the wafer by applying a laser beam from one surface side of the wafer along the outer periphery at a location on the inside of the outer periphery by a predetermined distance; and a grinding step for grinding the surface to be ground of the wafer whose outer peripheral portion has been removed, to a predetermined finish thickness.

1 . A wafer grinding method for grinding a surface to be ground of a wafer having an arcuatedly chamfered outer peripheral surface, comprising: 
 an outer peripheral portion removal step for removing the outer peripheral portion of the wafer by applying a laser beam from one surface side of the wafer along the outer periphery at a location on the inside of the outer periphery by a predetermined distance; and    a grinding step for grinding the surface to be ground of the wafer whose outer peripheral portion has been removed, to a predetermined finish thickness.    
     
     
         2 . The wafer grinding method according to  claim 1 , wherein a plurality of function elements are formed on the front surface of the wafer, and the surface to be ground of the wafer is the back surface.  
     
     
         3 . The wafer grinding method according to  claim 1 , wherein the outer peripheral portion removal step comprises applying a laser beam of a wavelength capable of passing through the wafer along the outer periphery to form an annular deteriorated layer along the outer periphery in the inside of the wafer and dividing the wafer along the deteriorated layer.  
     
     
         4 . The wafer grinding method according to  claim 1 , wherein the outer peripheral portion removal step is to form an annular groove, which reaches the other side from one side along the outer periphery of the wafer by applying a laser beam of a wavelength having absorptivity for the wafer.  
     
     
         5 . A wafer grinding method for grinding the back surface of a wafer having a plurality of function elements on the front surface thereof and an arcuatedly chamfered outer peripheral surface, comprising: 
 a groove forming step for forming an annular groove deeper than at least the finish thickness of the wafer from the front surface of the wafer by applying a laser beam of a wavelength having absorptivity for the wafer from the front surface of the wafer along the outer periphery at a location on the inside of the outer periphery by a predetermined distance; and    a grinding step for grinding the back surface of the wafer having the groove formed thereon, to a predetermined finish thickness.