Carrier head and chemical mechanical polishing apparatus

Abstract

Provided are a carrier head and a chemical mechanical polishing apparatus. The carrier head includes a body having a ring shape; a supporting unit surrounding the body; a retainer ring having a ring shape, the retainer ring surrounding the supporting unit; a membrane member on the supporting unit and within an inner circumference of the retainer ring; and an external ring on an outer surface of the membrane member, the external ring having a hydrophobic surface.

What is claimed is: 
     
         1 . A carrier head, comprising:
 a body having a ring shape;   a supporting unit surrounding the body;   a retainer ring having a ring shape, the retainer ring surrounding the supporting unit;   a membrane member on the supporting unit and within an inner circumference of the retainer ring; and   an external ring on an outer surface of the membrane member, the external ring having a hydrophobic surface.   
     
     
         2 . The carrier head as claimed in  claim 1 , wherein the external ring includes a metal frame. 
     
     
         3 . The carrier head as claimed in  claim 2 , wherein the metal frame is coated with a hydrophobic material. 
     
     
         4 . The carrier head as claimed in  claim 3 , wherein the hydrophobic material is a fluoride compound. 
     
     
         5 . The carrier head as claimed in  claim 3 , wherein the hydrophobic material is polytetrafluoroethylene (PTFE). 
     
     
         6 . The carrier head as claimed in  claim 1 , wherein:
 the external ring supports an outer surface of the membrane member, and   an outer surface of the external ring and the outer surface of the membrane are spaced apart from an inner surface of the retainer ring.   
     
     
         7 . The carrier head as claimed in  claim 1 , wherein:
 the membrane member presses against a substrate during a polishing process of the substrate; and   a contact angle between a surface of the external ring and a drop of slurry supplied to the substrate during the polishing process is 90° or more.   
     
     
         8 . A chemical mechanical polishing apparatus, comprising:
 a base;   a platen on the base and having a polishing pad on a surface thereof;   a slurry supply arm adjacent to the platen and on the base, the slurry supply arm supplying slurry to a surface of the polishing pad; and   a carrier head configured to press and support the polishing pad while operating, the carrier head including:   a body having a ring shape;   a supporting unit surrounding the body;   a retainer ring having a ring shape, the retainer ring surrounding the supporting unit;   a membrane member on the supporting unit and within an inner circumference of the retainer ring; and   an external ring on an outer surface of the membrane member, the retainer ring having a hydrophobic surface.   
     
     
         9 . The chemical mechanical polishing apparatus as claimed in  claim 8 , wherein the slurry includes an oxide based compound. 
     
     
         10 . The chemical mechanical polishing apparatus as claimed in  claim 8 , wherein a contact angle between a drop of the slurry and a surface of the external ring is 90° or more. 
     
     
         11 . The chemical mechanical polishing apparatus as claimed in  claim 8 , wherein the external ring includes a metal frame coated with a hydrophobic material. 
     
     
         12 . The chemical mechanical polishing apparatus as claimed in  claim 11 , wherein the hydrophobic material is a fluoride compound. 
     
     
         13 . The chemical mechanical polishing apparatus as claimed in  claim 12 , wherein the fluoride compound is polytetrafluoroethylene (PTFE). 
     
     
         14 . The chemical mechanical polishing apparatus as claimed in  claim 8 , the carrier head further including:
 a first hanging part protruding in a ring shape and having a first coupling surface on a surface thereof on an outer surface of the body, and   a second hanging part vertically facing the first hanging part and having a second coupling surface on a surface thereof on an inner surface of the supporting unit.   
     
     
         15 . The chemical mechanical polishing apparatus as claimed in  claim 14 , the carrier head further including a sealing film having one end fixed to the body under the first coupling surface and the other end fixed to the supporting unit under the second coupling surface. 
     
     
         16 . A carrier head of a chemical mechanical polishing apparatus, the carrier head comprising:
 a body having a ring shape;   a supporting unit surrounding the body;   a retainer ring having a ring shape, the retainer ring surrounding the supporting unit;   a membrane member on the supporting unit and within an inner circumference of the retainer ring; and   an external ring on an outer surface of the membrane member, a contact angle between an exposed surface of the external ring and a drop of slurry being 90° or more.   
     
     
         17 . The carrier head as claimed in  claim 16 , wherein the slurry includes an oxide based compound. 
     
     
         18 . The carrier head as claimed in  claim 16 , wherein the slurry includes potassium hydroxide. 
     
     
         19 . The carrier head as claimed in  claim 18 , wherein the slurry further includes abrasive particles. 
     
     
         20 . The carrier head as claimed in  claim 19 , wherein the abrasive particles include silica.