Chemical mechanical polishing method and apparatus for removing material from a surface of a workpiece that includes low-k material

Abstract

Improved method and apparatus for removing material from a surface of a workpiece including a low dielectric constant material are disclose. The apparatus includes a platen, having a polishing surface attached thereto, configured to orbit at more than about 500 revolutions per minute and a workpiece carrier configured to rotate and apply about 0.25 to about 2 psi. to the workpiece in the direction of the platen.

What is claimed is:  
     
         1 . An apparatus for polishing a surface of a workpiece, the surface including a low dielectric material, comprising: 
 a platen configured to orbit about an axis at a speed up to about 2000 revolutions per minute;    a polishing surface attached to the platen; and    a workpiece carrier proximate the polishing surface.    
     
     
         2 . The apparatus of  claim 1 , wherein the platen is configured to rotate at about 1000 orbits per minute.  
     
     
         3 . The apparatus of  claim 1 , wherein the platen is further configured to dither.  
     
     
         4 . The apparatus of  claim 1 , wherein the platen rotates with an orbital radius of about 0.25 to about 1 inch.  
     
     
         5 . The apparatus of  claim 1 , wherein the carrier and the platen are configured to move the workpiece relative to the polishing surface at a speed of about 0.8 to about 3.2 meters per second.  
     
     
         6 . The apparatus of  claim 1 , wherein the carrier is configured to apply about 0.25 to about 2 pounds per square inch pressure to the workpiece in the direction of the polishing surface.  
     
     
         7 . The apparatus of  claim 1 , wherein the platen includes channels configured to allow polishing solution to circulate through a portion of the platen.  
     
     
         8 . The apparatus of  claim 7 , wherein the platen is configured to allow the polishing slurry to flow at a rate of about 120 to about 200 milliliters per minute.  
     
     
         9 . The apparatus of  claim 1 , wherein the platen is configured to orbit at a speed of about 500 to about 2000 orbits per minute.  
     
     
         10 . The apparatus of  claim 1 , wherein the carrier includes a bladder to regulate pressure applied to the workpiece.  
     
     
         11 . The apparatus of  claim 1 , wherein the platen includes a conduit configured to allow heat exchange fluid to flow through a portion of the platen.  
     
     
         12 . A polishing system for removing material from a wafer surface, the wafer including low-k material, comprising: 
 a plurality of polishing stations, wherein at least one of said plurality of polishing stations includes a platen configured to move at about 0.8 to about 3.2 meters per second relative to the wafer surface;    a clean system including at least one clean station; and    a load station.    
     
     
         13 . The polishing system of clam  12 , further comprising a buff station.  
     
     
         14 . The polishing system of  claim 12 , further comprising a carousel carrier apparatus including a plurality of workpiece carriers.  
     
     
         15 . The polishing system of  claim 14 , wherein the plurality of workpiece carriers are configured to rotate about an axis and translate in a radial direction.  
     
     
         16 . The polishing system of  claim 14 , wherein at least one of said plurality of workpiece carriers is configured to apply a about 0.25 to about 2 pounds per square inch to the workpiece in the direction of the platen.  
     
     
         17 . The polishing system of  claim 12 , further comprising a workpiece carrier configured to rotate about an axis and apply about 0.25 to about 2 pounds per square inch to the workpiece in the direction of the platen.  
     
     
         18 . The polishing system of  claim 12 , wherein the platen is configured to orbit.  
     
     
         19 . The polishing system of  claim 18 , wherein the platen is configured to orbit with a radius of about 0.25 to about 1 inch.  
     
     
         20 . The polishing system of  claim 12 , wherein the platen is configured to orbit about an axis at a speed of about 500 to about 2000 orbits per minute.  
     
     
         21 . The polishing system of  claim 12 , further comprising a temperature control system configured to regulate a temperature of a polishing fluid.  
     
     
         22 . The polishing system of  claim 12 , wherein the platen includes channels to allow polishing fluid to flow through a portion of the platen.  
     
     
         23 . The polishing system of  claim 12 , wherein the platen includes a groove configured to allow heat exchange fluid to flow through a portion of the platen.  
     
     
         24 . The polishing system of  claim 12 , further comprising a polishing surface attached to the platen, the polishing surface including apertures to allow polishing fluid to circulate through a portion of the polishing surface.  
     
     
         25 . A polishing system for removing conductive material deposited onto low-k material, comprising: 
 a load and unload station;    a plurality of polishing stations, wherein at least one polishing station includes a platen configured to move relative to a workpiece surface at about 0.8 to about 3.2 meters per second and a workpiece carrier configured to apply about 0.25 to about 2 psi to a workpiece in the direction of the platen; and    a clean system proximate the plurality of polishing station.    
     
     
         26 . A method for removing material from a surface of a workpiece, including low-k material, comprising the steps of: 
 providing a workpiece;    placing the workpiece in contact with a polishing surface; and    orbiting the polishing surface at a speed about 500 to about orbits per minute.    
     
     
         27 . The method of  claim 26 , further comprising the step of rotating the wafer.  
     
     
         28 . The method of  claim 26 , further comprising the step of applying about 0.25 to about 2 pounds per square inch to the workpiece in the direction of the polishing surface.  
     
     
         29 . The method of  claim 26 , further comprising the step of circulating polishing fluid through a portion of the platen.  
     
     
         30 . The method of  claim 26 , further comprising the step of regulating the temperature of the polishing surface.  
     
     
         31 . The method of  claim 26 , further comprising the step of regulating the temperature of a polishing fluid.  
     
     
         32 . An apparatus for polishing a surface of a workpiece, the surface including a low dielectric material, comprising: 
 a platen configured to move about an axis;    a polishing surface attached to the platen; and    a workpiece carrier proximate the polishing surface, wherein the platen and the workpiece carrier are configured such that the surface of the workpiece and the platen move at a relative speed of about 0.8 to about 3.2 meters per second.    
     
     
         33 . A method for removing material from a surface of a workpiece, including low-k material, comprising the steps of: 
 providing a workpiece;    placing the workpiece in contact with a polishing surface; and    moving the polishing surface and the workpiece relative to each other at a speed of about 0.8 to about 3.2 meters per second.