Method for grinding wafers by shaping resilient chuck covering

Abstract

This method facilitates and improves the production of quality thin wafers by adhering traditional resilient back-grind tape that has been perforated over the area that will contact the wafer on the ceramic porous grind chuck, so as to allow vacuum to be applied to the wafer back surface to hold the wafer for processing. The tape adhering to the chuck is ground with a abrasive grind wheel, bringing the surface of the tape parallel to the chuck surface which was previously ground by the same grinding device. Grinding the tape while it is mounted on the chuck establishes the plane perpendicular to the grind wheel spindle, removes the bumpiness from the perforation holes and evens out the non-uniformity of the tape, resulting in improved wafer back side grinding and thus good site flatness.

What is claimed is: 
     
         1 . A method of grinding a first wafer having first and second surfaces comprising the steps of:
 providing a grind chuck having first and second surfaces;   providing a first resilient member having top and bottom surfaces;   cutting the resilient member to a size and shape that conforms to said first surface of said chuck;   placing said bottom surface of said resilient member on the first surface of said chuck;   grinding the top surface of the resilient member to remove debris therefrom and shape the top surface thereof utilizing a first grinding apparatus;   placing said first wafer on said top surface of said resilient member;   securing said first wafer to said grind chuck; and   grinding the first surface of said first wafer to the desired shape using said first grinding apparatus.   
     
     
         2 . The method of  claim 1  wherein openings are formed in said resilient member. 
     
     
         3 . The method of  claim 1  wherein said grinding chuck is porous. 
     
     
         4 . The method of  claim 1  wherein openings are formed in said grind chuck. 
     
     
         5 . The method of  claim 1  further including the step of removing said first wafer from said grinding chuck and inverting said first wafer such that said second surface thereof faces said first chuck surface. 
     
     
         6 . The method of  claim 5  wherein a vacuum is provided to secure said wafer to said grind chuck. 
     
     
         7 . The method of  claim 5  wherein the second surface of said first wafer is removably positioned on said first chuck surface. 
     
     
         8 . The method of  claim 3  wherein said second surface of said wafer is ground by said first grinding apparatus. 
     
     
         9 . The method of  claim 5  further including the step of removing said first wafer from said chuck. 
     
     
         10 . The ground method of  claim 1  further including the step of replacing said fist wafer with a second wafer. 
     
     
         11 . The method of  claim 1  wherein said first resilient member is removed from said ground chuck and replaced with a second resilient member. 
     
     
         12 . The method of  claim 11  wherein said second resilient member is processed in the same manner as said first resilient member. 
     
     
         13 . The method of  claim 1  wherein said resilient member comprises a tape. 
     
     
         14 . The method of  claim 1  wherein said resilient member comprises material selected from the group comprising Ultron 1034R-9.8 or Ultron 1044R-9.8. 
     
     
         15 . The method of  claim 14  wherein the selected material is Ultron 1034R-9.8. 
     
     
         16 . The method of  claim 14  wherein the selected material is Ultron 1044R-9.8.