Double side grinding apparatus having convex polygon-shaped abrasive members

Abstract

Methods and apparatus for simultaneous double-side grinding semiconductor structures are disclosed. The double-side grinding apparatus may include first and second grinding wheels each having abrasive members that are shaped as a convex polygon (e.g., convex pentagon).

1 . A method for double side grinding a semiconductor structure, the method comprising:
 positioning the semiconductor structure between first and second grinding wheels, each grinding wheel comprising:
 a support wheel; and 
 a plurality of abrasive members that extend axially outward from the support wheel, each abrasive member having a wafer-engaging surface, the wafer-engaging surface being shaped as a convex polygon with at least five sides; and 
   grinding the semiconductor structure by contacting the first and second grinding wheels with the semiconductor structure and rotating the first and second grinding wheels relative to each other.   
     
     
         2 . The method as set forth in  claim 1  wherein the convex polygon has one or more rounded corners. 
     
     
         3 . The method as set forth in  claim 2  wherein one of the sides of the polygon comprise a base and a plurality of sides other than the base, wherein each of the corners formed between two sides of the polygon other than the base are rounded. 
     
     
         4 . The method as set forth in  claim 3  wherein each of the corners formed with the base are sharp corners. 
     
     
         5 . The method as set forth in  claim 1  wherein the abrasive members comprise diamond grit. 
     
     
         6 - 8 . (canceled) 
     
     
         9 . The method as set forth in  claim 1  wherein the convex polygon is a convex pentagon. 
     
     
         10 . (canceled) 
     
     
         11 . A method for double side grinding a semiconductor structure, the method comprising:
 positioning the semiconductor structure between first and second grinding wheels, each grinding wheel comprising:
 a support wheel; and 
 a plurality of abrasive members that extend axially outward from the support wheel, each abrasive member having a wafer-engaging surface, the wafer-engaging surface comprising:
 a base, the base being a first side of the wafer-engaging surface; 
 a second side having a first end and a second end, the second side being connected to the base at its first end, the second side and base forming an obtuse angle; and 
 a third side having a first end and a second end, the third side being connected to the base at its first end, the third side and base forming an obtuse angle; and 
 
   grinding the semiconductor structure by contacting the first and second grinding wheels with the semiconductor structure and rotating the first and second grinding wheels relative to each other.   
     
     
         12 . (canceled) 
     
     
         13 . The method as set forth in  claim 11  wherein each grinding wheel has a rotational axis, each side of the wafer-engaging surface having an average distance from the rotational axis, wherein the average distance of the base from the rotational axis is greater than the average distance from the rotational axis of each of the other sides. 
     
     
         14 . The method as set forth in  claim 11  wherein each grinding wheel has a rotational axis, each side of the wafer-engaging surface having an average distance from the rotational axis, wherein the average distance of the base from the rotational axis is less than the average distance from the rotational axis of each of the other sides. 
     
     
         15 - 17 . (canceled) 
     
     
         18 . The method as set forth in  claim 11  wherein the abrasive members comprise diamond grit. 
     
     
         19 - 22 . (canceled) 
     
     
         23 . A double side grinding apparatus comprising:
 first and second grinding wheels, each grinding wheel having a rotational axis and comprises:
 a support wheel; and 
 a plurality of abrasive members that extend axially outward from the support wheel, each abrasive member having a wafer-engaging surface, the wafer-engaging surface comprising:
 a base, the base being a first side of the wafer-engaging surface; 
 a second side having a first end and a second end, the second side being connected to the base at its first end, the second side and base forming an obtuse angle; and 
 a third side having a first end and a second end, the third side being connected to the base at its first end, the third side and base forming an obtuse angle; and 
 
   each side of the wafer-engaging surface having an average distance from the rotational axis, wherein the average distance of the base from the rotational axis is less than the average distance of each of the other sides from the rotational axis.   
     
     
         24 . The double side grinding apparatus as set forth in  claim 23  wherein the wafer-engaging surface comprises a fourth side and a fifth side. 
     
     
         25 . The double side grinding apparatus as set forth in  claim 23  wherein the wafer-engaging surface has one or more rounded corners. 
     
     
         26 . The double side grinding apparatus as set forth in  claim 25  wherein the corner formed between the base and the second side is not rounded and the corner formed between the base and the third side is not rounded. 
     
     
         27 . The double side grinding apparatus as set forth in  claim 23  wherein the wafer-engaging surface is pentagon-shaped and comprises a fourth side and a fifth side. 
     
     
         28 . The double side grinding apparatus as set forth in  claim 23  wherein the abrasive members comprise diamond grit. 
     
     
         29 . The double side grinding apparatus as set forth in  claim 28  wherein the abrasive members comprise vitrified diamond. 
     
     
         30 . The double side grinding apparatus as set forth in  claim 23  wherein the support wheel forms a circumferential recess, the abrasive members being disposed within the circumferential recess. 
     
     
         31 . The double side grinding apparatus as set forth in  claim 23  wherein the support wheel forms a circumferential recess and the abrasives are connected to a collar, the collar being disposed within the circumferential recess. 
     
     
         32 . The double side grinding apparatus as set forth in  claim 23  further comprising first and second hydrostatic pads for securing a wafer.