Method for improving curvature of the polished surface by chemical mechanical polishing

Abstract

This invention relates to a method for improving curvature of the polished surface by chemical mechanical polishing comprising a polishing table, a polishing pad, a polishing head and a slurry exhaust system. The polishing head comprises a revolving spindle and the slurry exhaust system comprises a slurry outlet. The method for improving curve rate of the polished surface by chemical mechanical polishing is in order to make the slurry distributing on the polishing pad non-uniformly in controlling to control removing rate on each point of the polishing surface by the concentration of the slurry. This method will improve the defects in non-smooth on the wafer-polishing surface to make the wafer-polishing surface in full flatness after polishing.

What is claimed is:  
     
         1 . A method for improving polishing surface qualities in chemical mechanical polishing process, said method comprising: 
 laying a polishing pad on a polishing table;    using a movable slurry exhaust mechanism to provide a mixed slurry on said polishing pad, said mixed slurry comprising a chemical solution and a slurry;    placing a wafer on the polishing pad by a head; and    polishing said wafer by using said mixed slurry and said polishing pad.    
     
     
         2 . The method according to  claim 1 , wherein said polishing table is a table adapted to polishing said wafer.  
     
     
         3 . The method according to  claim 2 , wherein said polishing table is a linear movable, the moving direction of a polishing surface on said linear movable polishing table is perpendicular to the axis of said head.  
     
     
         4 . The method according to  claim 2 , wherein said polishing table is rotatly movable and is rotated by a revolving spindle which is parallel to the axis of said head.  
     
     
         5 . The method according to  claim 1 , wherein said wafer is further comprising a substrate and a polishing layer.  
     
     
         6 . The method according to  claim 1 , wherein said movable slurry exhaust mechanism is a rotated baton element and the central axis of said movable slurry exhaust mechanism is parallel to the axis of said head.  
     
     
         7 . The method according to  claim 6 , wherein said movable slurry exhaust mechanism further comprises a fluid outlet.  
     
     
         8 . The method according to  claim 1 , wherein said mixed slurry further comprises a fluid with small particles.  
     
     
         9 . The method according to  claim 1 , wherein said chemical solution is unable to cause a bad chemical reaction with wafer polishing surface.  
     
     
         10 . A method for improving polishing surface qualities in chemical mechanical polishing process, said method comprising: 
 laying a polishing pad on a polishing table;    using a movable slurry exhaust mechanism to provide slurry on said polishing pad;    using a movable chemical solution exhaust mechanism to provide chemical solution on said polishing pad;    placing a wafer on the polishing pad by a head; and    polishing said wafer by using said slurry, said chemical solution and said polishing pad.    
     
     
         11 . The method according to  claim 10 , wherein said polishing table is a table adapted to polishing said wafer.  
     
     
         12 . The method according to  claim 11 , wherein said polishing table is linear movable, the moving direction of a polishing surface on said linear movable polishing table is perpendicular to the axis of said head.  
     
     
         13 . The method according to  claim 11 , wherein said polishing table is ratatly movable and is rotated by a revolving spindle which is parallel to the axis of said head.  
     
     
         14 . The method according to  claim 10 , wherein said wafer further comprises a substrate and a polishing layer.  
     
     
         15 . The method according to  claim 10 , wherein said movable slurry exhaust mechanism is a rotated baton element and the central axis of said movable slurry exhaust mechanism is parallel to the axis of said head.  
     
     
         16 . The method according to  claim 15 , wherein said movable slurry exhaust mechanism further comprises a slurry outlet.  
     
     
         17 . The method according to  claim 10 , wherein said movable chemical solution exhaust mechanism is a movable baton element.  
     
     
         18 . The method according to  claim 17 , wherein said movable chemical solution exhaust mechanism further comprises a mechanical solution outlet.  
     
     
         19 . The method according to  claim 10 , wherein said chemical solution further comprises a fluid with small particles.  
     
     
         20 . The method according to  claim 10 , wherein said chemical solution is unable to cause a bad chemical reaction with wafer surface.  
     
     
         21 . A method for improving polishing surface qualities in chemical mechanical polishing process, said method comprising: 
 laying a polishing pad on a polishing table;    using a slurry exhaust system under said polishing table to provide a slurry on said polishing pad, said slurry further comprising a chemical solution which is unable to cause a bad chemical reaction with wafer surface to dilute said slurry;    placing a wafer on the polishing pad; and    polishing said wafer by using said slurry and said polishing pad.    
     
     
         22 . The method according to  claim 21 , wherein said polishing table is a table adapted to polishing said wafer.  
     
     
         23 . The method according to  claim 22 , wherein said polishing table is rotatly movable and is rotated by a revolving spindle which is parallel to the axis of said head.  
     
     
         24 . The method according to  claim 21 , wherein said wafer further comprises a substrate and a polishing layer.  
     
     
         25 . The method according to  claim 21 , wherein said slurry further comprises a fluid with small particles.