Polishing pad and the method of forming micro-structure thereof

Abstract

This invention is related to a polishing pad, and more particularly a polishing pad with flexible micro-structure. The polishing pad comprises a connecting surface and a polishing surface. The connecting surface is used to secure on a polishing device. The polishing surface with flexible micro-structure is used to grind and adequately press close to the surface of semiconductor piece. The present invention not only increases the area of polishing surface that contact with the semiconductor piece but also get over the difficulty in pressing close to different piece. It will save grinding time and have a better effect.

1 . A polishing pad, comprising:
 a connecting surface, configured for securing on a polishing device; and   a polishing surface, configured for polishing a semiconductor piece or a work piece;   wherein said polishing surface is with a flexible micro-structure to attach to surface of the semiconductor piece or the work piece and increase area of said polishing surface contact with said semiconductor piece or work piece.   
     
     
         2 . The polishing pad according to  claim 1 , wherein said micro-structure is a micro cave. 
     
     
         3 . The polishing pad according to  claim 2 , wherein a width of said micro cave is from 1 nanometer to 100 microns. 
     
     
         4 . The polishing pad according to  claim 1 , wherein said micro-structure is formed by a micro foaming technology. 
     
     
         5 . The polishing pad according to  claim 4 , wherein said micro foaming technology comprises a physical micro foaming technology. 
     
     
         6 . The polishing pad according to  claim 4 , wherein said micro foaming technology comprises a chemical micro foaming technology. 
     
     
         7 . The polishing pad according to  claim 4 , wherein said micro foaming technology comprises the steps:
 providing a resin;   providing a plurality of nano dots in said resin;   stirring said nano dots and said resin for distributing said nano dots in said resin;   curing said resin for forming a sheet; and   removing said nano dots for enabling a surface of said sheet with a plurality of cave holes to form said micro-structure.   
     
     
         8 . The polishing pad according to  claim 4 , wherein said micro foaming technology comprises the steps:
 providing a resin;   providing a plurality of salt dots in said resin;   stirring said salt dots and said resin for distributing said salt dots in said resin;   curing said resin for forming a sheet; and   removing said salt dots for enabling a surface of said sheet with a plurality of cave holes to form said micro-structure.   
     
     
         9 . The polishing pad according to  claim 8 , wherein said removing step comprises removing said salt dots with water. 
     
     
         10 . The polishing pad according to  claim 4 , wherein said micro foaming technology comprises the steps:
 providing a resin;   providing a solvent in said resin, wherein said resin is insolvable with said solvent;   stirring said solvent and said resin for distributing said solvent in said resin;   curing said resin for forming a sheet; and   removing said solvent for enabling a surface of said sheet with a plurality of cave holes to form said micro-structure.   
     
     
         11 . The polishing pad according to  claim 10 , wherein said solvent comprises a hydrophilic solvent. 
     
     
         12 . The polishing pad according to  claim 10 , wherein said solvent comprises dimethyl formamide (DMF). 
     
     
         13 . The polishing pad according to  claim 10 , wherein said removing step comprises removing said solvent with water. 
     
     
         14 . The polishing pad according to  claim 1 , wherein said polishing pad is attached to said polishing device with an adhesive glue. 
     
     
         15 . The polishing pad according to  claim 14 , wherein said adhesive glue comprises a press-sensitive glue. 
     
     
         16 . A method of forming a micro-structure on a polishing pad, comprising the steps:
 providing a substrate with thin fibers;   coating said substrate in a resin;   curing said coated substrate to form a sheet; and   polishing a surface of said sheet for forming a surface with said micro-structure.   
     
     
         17 . The method of forming a micro-structure on a polishing pad according to  claim 16 , wherein said micro-structure comprises a hair feather micro-structure. 
     
     
         18 . The method of forming a micro-structure on a polishing pad according to  claim 17 , wherein a dimension of said is from 1 nano meter to 100 microns. 
     
     
         19 . A method of forming a micro-structure on a polishing pad, comprising the steps:
 providing a resin;   providing a foaming agent in said resin;   stirring said resin and said foaming agent for distributing said foaming agent into said resin;   curing said resin for forming a sheet; and   heating said resin to vaporize said foaming agent to enable a surface of said sheet with a plurality of cave holes to form said micro-structure.   
     
     
         20 . The method of forming a micro-structure on a polishing pad according to  claim 19 , wherein said curing and said heating steps are implemented at same time.