Slurry distributor for chemical mechanical polishing apparatus and method of using the same

Abstract

A polishing apparatus ( 100 ) is provided for polishing a substrate ( 102 ) that has slurry distributor ( 125 ) which improves planarization uniformity. Generally, apparatus ( 100 ) includes: (i) platen ( 106 ) with polishing surface ( 110 ); (ii) head ( 116 ) adapted to hold substrate ( 102 ) against polishing surface; (iii) mechanism to rotate platen ( 106 ) during polishing; (iv) dispenser ( 124 ) having nozzles ( 126, 128 ) to dispense slurry on the surface ( 110 ); and (v) distributor ( 125 ) between the nozzles ( 126, 128 ) and head ( 116 ). In one embodiment, apparatus ( 100 ) further includes a wiper ( 180 ) between head ( 116 ) and distributor ( 125 ) to remove used slurry and polishing byproducts from surface ( 110 ), thereby reducing agglomerations or deposits that can damage substrate ( 102 ) and improving yield. Optionally, apparatus ( 100 ) further includes dispenser ( 186 ) for dispensing a fluid before and/or after wiper ( 180 ) to substantially eliminate buildup of deposits. Method for polishing and substrate polished according to method.

1 . A polishing apparatus for removing material from a surface of a substrate, the polishing apparatus comprising: 
 a platen having a polishing surface thereon;    a polishing head adapted to hold the substrate against the polishing surface during a polishing operation;    a drive mechanism for providing a relative motion between the polishing head and the polishing surface during the polishing operation;    a dispenser having at least one nozzle adapted to dispense polishing liquid on the polishing surface;    a distributor positioned between the nozzle of the dispenser and the polishing head; and    at least one spacer on a lower surface of the distributor, the at least one spacer positioned between the distributor and the polishing surface, and adapted to contact the polishing surface during the polishing operation and to position the distributor relative to the polishing surface;    the distributor mixing and uniformly distributing polishing liquid between the distributor and the polishing surface during the polishing operation when there is relative motion between the polishing head and the polishing surface during the polishing operation.    
   
   
       2 . A polishing apparatus according to  claim 1 , wherein the at least one spacer comprises an adjustment mechanism to adjust a gap between the lower surface of the distributor and the polishing surface, so that a rate of removal of material from the substrate can be varied.  
   
   
       3 . A polishing apparatus according to  claim 2 , wherein the adjustment mechanism comprises a threaded rod or screw, or shims.  
   
   
       4 . A polishing apparatus according to  claim 1 , wherein the at least one spacer comprises a material in contact with the polishing surface during the polishing operation selected from a group consisting of: 
 a polymeric material;    a ceramic material; and    a glass material.    
   
   
       5 . A polishing apparatus according to  claim 1 , wherein the distributor has a chambered edge.  
   
   
       6 . A polishing apparatus according to  claim 1 , wherein the distributor comprises an integral dispenser for dispensing the polishing liquid.  
   
   
       7 . A polishing apparatus according to  claim 1 , further comprising a wiper positioned above the polishing surface, for removing used polishing liquid and polishing byproducts from the polishing surface.  
   
   
       8 . A polishing liquid distributor comprising: 
 a distributor having a length greater than or substantially equal to a diameter of a polishing head holding a substrate to be polished; and    at least one spacer on a lower surface of the distributor, the at least one spacer positioned between the distributor and the polishing surface, and adapted to contact the polishing surface during a polishing operation and to position the distributor relative to the polishing surface, the distributor mixing and uniformly distributing polishing liquid between the distributor and the polishing surface during the polishing operation when there is relative motion between the polishing head and the polishing surface during the polishing operation.    
   
   
       9 . A polishing liquid distributor according to  claim 8 , wherein said distributor has a substantially planar lower surface separated from and in a facing relationship with the polishing surface.  
   
   
       10 . A polishing liquid distributor according to  claim 9 , wherein the at least one spacer comprises an adjustment mechanism to adjust a gap between the lower surface of the distributor and the polishing surface, so that a rate of removal of material from the substrate can be varied.  
   
   
       11 . A polishing liquid distributor according to  claim 10 , wherein the adjustment mechanism comprises a threaded rod or screw, or shims.  
   
   
       12 . A polishing liquid distributor according to  claim 8 , wherein the at least one spacer comprises a material in contact with the polishing surface during the polishing operation, the material selected from a group consisting of: 
 a polymeric material;    a ceramic material; and    a glass material.    
   
   
       13 . A polishing liquid distributor according to  claim 8 , wherein the distributor bar has a chambered edge.  
   
   
       14 . A polishing liquid distributor according to  claim 8 , wherein the distributor comprises an integral dispenser for dispensing the polishing liquid.  
   
   
       15 . A polishing liquid distributor according to  claim 8 , wherein the distributor comprises a distributor bar.  
   
   
       16 . A polishing liquid distributor according to  claim 8 , wherein the liquid distributor is for use in a chemical mechanical polishing apparatus.  
   
   
       17 . A polishing apparatus according to  claim 1 , wherein the distributor comprises a distributor bar.  
   
   
       18 . A polishing apparatus according to  claim 1 , wherein the polishing apparatus is a chemical mechanical polishing apparatus.  
   
   
       19 . A polishing apparatus for removing material from a surface of a substrate, the polishing apparatus comprising: 
 a platen having a polishing surface thereon;    a polishing head adapted to hold the substrate against the polishing surface during a polishing operation;    a drive mechanism for providing a relative motion between the polishing head and the polishing surface during the polishing operation;    a dispenser having at least one nozzle adapted to dispense polishing liquid on the polishing surface;    a distributor having at least one chambered edge and positioned between the nozzle of the dispenser and the polishing head, and having a substantially planar lower surface separated from and in a facing relationship with the polishing surface;    at least one spacer on a lower surface of the distributor, the at least one spacer positioned between the distributor and the polishing surface, and adapted to contact the polishing surface during the polishing operation and to position the distributor relative to the polishing surface, the distributor mixing and uniformly distributing polishing liquid between the distributor and the polishing surface during the polishing operation when there is relative motion between the polishing head and the polishing surface during the polishing operation; and    a wiper positioned above the polishing surface, for removing used polishing liquid and polishing byproducts from the polishing surface;    the at least one spacer comprises an adjustment mechanism to adjust a gap between the lower surface of the distributor and the polishing surface so that a rate of removal of material from the substrate can be varied, and comprises a material in contact with the polishing surface during the polishing operation selected from the group consisting of a polymeric material, a ceramic material; and a glass material; and    the adjustment mechanism comprising a threaded rod or screw, or shims.    
   
   
       20 . A method of removing material from a surface of a substrate, the method comprising: 
 providing a platen having a polishing surface thereon;    holding the substrate against the polishing surface in a polishing head during a polishing operation;    generating a relative motion between the polishing head and the polishing surface during the polishing operation;    dispensing polishing liquid on the polishing surface from a dispenser having at least one nozzle;    positioning a distributor between the nozzle of the dispenser and the polishing head; and    positioning at least one spacer on a lower surface of the distributor, the at least one spacer being positioned between the distributor and the polishing surface, and adapted to contact the polishing surface during the polishing operation and to position the distributor relative to the polishing surface,    mixing and uniformly distributing polishing liquid with the distributor between the distributor and the polishing surface during the polishing operation when there is relative motion between the polishing head and the polishing surface during the polishing operation.    
   
   
       21 . A method according to  claim 20 , wherein the removing material from a surface of a substrate comprises polishing a surface of a substrate.  
   
   
       22 . A method according to  claim 20 , wherein the removing material from a surface of a substrate comprises planarizing a surface of a semiconductor wafer.  
   
   
       23 . A substrate polished according to the method of  claim 21 .  
   
   
       24 . A semiconductor wafer planarized according to the method of  claim 22.