Retaining ring having reduced wear and contamination rate for a polishing head of a CMP tool

Abstract

A retaining member for a polishing head in a CMP apparatus comprises a bottom surface with silicon carbide. Due to the superior characteristics of silicon carbide, a low wear rate of the retaining member is secured, wherein, additionally, accumulation of electrostatic charges is substantially avoided due to the conductivity of silicon carbide. Consequently, cost of ownership is reduced, while at the same time process stability over a large number of substrates is increased.

What is claimed:  
     
         1 . A retaining member for a polishing head, the retaining member being partially comprised of silicon carbide.  
     
     
         2 . The retaining member of  claim 1 , having an upper portion and a lower portion, the lower portion having a bottom surface that is comprised of silicon carbide.  
     
     
         3 . The retaining member of  claim 1 , wherein a plurality of slurry channels are formed in a bottom surface of said retaining member.  
     
     
         4 . The retaining member of  claim 2 , wherein said bottom surface comprises a surface topography configured to obtain a conditioning effect in a polishing pad during operation.  
     
     
         5 . The retaining member of  claim 2 , wherein said upper portion includes a flexible material.  
     
     
         6 . The retaining member of  claim 4 , wherein said surface topography includes a plurality of protrusions.  
     
     
         7 . The retaining member of  claim 4 , wherein said surface topography includes portions having a roughness on a microstructure scale.  
     
     
         8 . A polishing head for a CMP apparatus, comprising: 
 a support surface configured to receive a substrate; and    a retaining member configured to laterally fix the substrate on the support surface, the retaining member being partially comprised of silicon carbide.    
     
     
         9 . The polishing head of  claim 8 , wherein said retaining member comprises an upper portion and a lower portion, the lower portion having a bottom surface that is comprised of silicon carbide.  
     
     
         10 . The polishing head of  claim 8 , wherein a plurality of slurry channels are formed in a bottom surface of said retaining member.  
     
     
         11 . The polishing head of  claim 9 , wherein said bottom surface comprises a surface topography configured to obtain a conditioning effect in a polishing pad during operation.  
     
     
         12 . The polishing head of  claim 9 , wherein said upper portion includes a flexible material.  
     
     
         13 . The polishing head of  claim 11 , wherein said surface topography includes a plurality of protrusions.  
     
     
         14 . The polishing head of  claim 11 , wherein said surface topography includes portions having a roughness on a microstructure scale.  
     
     
         15 . A CMP apparatus, comprising: 
 a polishing pad attached to a polishing platen;    a polishing head including a retaining member that is partially comprised of silicon carbide; and    a pad conditioner having a surface portion in contact with the polishing pad and comprised of silicon carbide.    
     
     
         16 . A retaining member, comprising: 
 a lower portion formed of a conductive non-metal material; and    an upper portion formed of a material other than said non-metal material, wherein said conductive non-metal material is more rigid than said other material.    
     
     
         17 . The retaining member of  claim 16 , wherein said non-metal comprises silicon carbide.  
     
     
         18 . The retaining member of  claim 16 , wherein a plurality of slurry channels are formed in a bottom surface of said retaining member.  
     
     
         19 . The retaining member of  claim 18 , wherein said bottom surface comprises a surface topography configured to obtain a conditioning effect in a polishing pad during operation.  
     
     
         20 . The retaining member of  claim 18 , wherein said upper portion includes a flexible material.  
     
     
         21 . The retaining member of  claim 19 , wherein said surface topography includes a plurality of protrusions.  
     
     
         22 . The retaining member of  claim 19 , wherein said surface topography includes portions having a roughness on a microstructure scale.  
     
     
         23 . The retaining member of  claim 16 , wherein said lower portion comprises a material having a hardness of 15.0 GPa or more.  
     
     
         24 . A polishing head for a CMP apparatus, comprising: 
 a support surface configured to receive a substrate; and    a retaining member configured to laterally fix said substrate on said support surface, said retaining member comprising a lower portion including a conductive nonmetal material, and an upper portion formed of a material other than said conductive non-metal material, wherein said other material is less rigid than said conductive non-metal material.    
     
     
         25 . The polishing head of  claim 24 , wherein said non-metal material comprises silicon carbide.  
     
     
         26 . The polishing head of  claim 24 , wherein a plurality of slurry channels are formed in a bottom surface of said retaining member.  
     
     
         27 . The polishing head of  claim 24 , wherein a bottom surface of said retaining member comprises a surface topography configured to obtain a conditioning effect in a polishing pad during operation.  
     
     
         28 . The polishing head of  claim 24 , wherein said upper portion includes a flexible material.  
     
     
         29 . The polishing head of  claim 27 , wherein said surface topography includes a plurality of protrusions.  
     
     
         30 . The polishing head of  claim 27 , wherein said surface topography includes portions having a roughness on a microstructure scale.  
     
     
         31 . The polishing head of  claim 24 , wherein at least a bottom surface of said lower portion is comprised of a material having a hardness of 15.0 GPa or more.