Method for forming scribed groove and scribing apparatus

Abstract

A method for forming scribed grooves on a wafer and an apparatus for implementing the method. The method moves the cutting part such that its cutting edge forms an inverted trapezoid-shaped path, thereby reducing the scribing angle of the cutting edge to an acute angle. Consequently, the stress produced by the mechanical shock at the time of the scribing can be dispersed in the moving direction of the cutting edge and in a direction perpendicular to the surface of the wafer. The horizontal movement of the scribing cutting edge in the wafer enables the application of a sufficient load in a direction perpendicular to the scribing plane in the wafer. Consequently, vertical cracks are sufficiently generated, and the amount of dimensional deviation between the scribed groove and the cleaved plane is reduced. This method can produce chips featuring outside dimensions with higher precision and cleaved surfaces with high-quality mirror finish.

1 - 4 . (canceled)  
   
   
       5 . A scribing apparatus, comprising: 
 (a) a cutting part that has a cutting edge and that forms a scribed groove at the surface portion of a wafer;    (b) a horizontally moving portion that moves the cutting part horizontally to form the scribed groove;    (c) a vertically moving portion that moves the cutting part vertically to form the scribed groove; and    (d) a controlling section that: 
 (d1) expresses the location of the cutting edge as the horizontal coordinate and the vertical coordinate; and  
 (d2) based on the coordinate data, operates the horizontally moving portion and the vertically moving portion.  
   
   
   
       6 . A scribing apparatus as defined by  claim 5 , the scribing apparatus further comprising: 
 (a) an image pickup portion that picks up the image of the cutting edge; and    (b) a cutting-edge angle-adjusting portion that, based on the picked-up image data, adjusts the angle of the cutting edge against the surface of the wafer.    
   
   
       7 . A scribing apparatus as defined by  claim 5 , the scribing apparatus further comprising a thickness-measuring portion that measures the thickness of the wafer.  
   
   
       8 . A scribing apparatus as defined by  claim 6 , the scribing apparatus further comprising a thickness-measuring portion that measures the thickness of the wafer.