Retainer ring, substrate holding apparatus, and polishing apparatus, and retainer ring maintenance method

Abstract

According to one embodiment, a retainer ring for retaining a substrate to be polished, includes: an inside ring arranged to enclose the substrate; and an outside ring arranged outside the inside ring, abrasion-resistant of the outside ring being higher than abrasion-resistant of the inside ring, wherein the inside ring having a thickness in a radial direction in a range from a minimum of 0.05 mm to a maximum of 5 mm.

1 . A retainer ring for retaining a substrate to be polished, the retainer ring comprising:
 an inside ring arranged to enclose the substrate; and   an outside ring arranged outside the inside ring, abrasion-resistant of the outside ring being higher than abrasion-resistant of the inside ring,   wherein the inside ring having a thickness in a radial direction in a range from a minimum of 0.05 mm to a maximum of 5 mm.   
     
     
         2 . The retainer ring according to  claim 1 , wherein a convex portion toward the polishing pad is formed on a lower surface of the outside ring. 
     
     
         3 . The retainer ring according to  claim 2 , wherein a distance between a tip of the convex portion and an end of the outside ring with no convex portion is below 30 μm. 
     
     
         4 . The retainer ring according to  claim 1 , wherein the inside ring is detachably attached to the outside ring. 
     
     
         5 . The retainer ring according to  claim 1 , wherein a material of the inside ring includes one or more of PPS, PEEK, PTFE, PP, PET, polycarbonate, and polyacetal. 
     
     
         6 . The retainer ring according to  claim 1 , wherein a material of the outside ring includes one or more of ceramic materials and metallic materials. 
     
     
         7 . The retainer ring according to  claim 1 , wherein surface roughness of a lower surface of the outside ring is a maximum of Ra 1.6 μm. 
     
     
         8 . The retainer ring according to  claim 1 , wherein Rockwell M hardness of the inside ring is in a range from a minimum of 70 to a maximum of 120. 
     
     
         9 . The retainer ring according to  claim 1 , wherein on a lower surface of the inside ring and a lower surface of the outside ring, a plurality of grooves extending in radial directions and communicating the inside ring and the outside ring are formed. 
     
     
         10 . A substrate holding apparatus comprising:
 a top ring body for holding a substrate; and   the retainer ring according to  claim 1 , the retainer ring being arranged to enclose the substrate held by the top ring body.   
     
     
         11 . A polishing apparatus comprising:
 a polishing pad; and   the substrate holding apparatus according to  claim 10 , the substrate holding apparatus pressing the substrate onto the polishing pad.   
     
     
         12 . A method for maintaining a retainer ring for retaining a substrate to be polished, the retainer ring comprising:
 an inside ring arranged to enclose the substrate; and   an outside ring arranged outside the inside ring, abrasion-resistant of the outside ring being higher than abrasion-resistant of the inside ring,   wherein the inside ring having a thickness in a radial direction in a range from a minimum of 0.05 mm to a maximum of 5 mm, and   wherein the inside ring is detachably attached to the outside ring,   the method comprising:   removing the inside ring from the outside ring; and   fixing a new inside ring onto the outside ring.   
     
     
         13 . A retainer ring for retaining a substrate to be polished, the retainer ring comprising:
 an inside ring arranged to enclose the substrate; and   an outside ring arranged outside the inside ring, the outside ring comprising a lower ring and an upper ring,   wherein abrasion-resistant of the lower ring is higher than abrasion-resistant of the inside ring, and   toughness of the upper ring is higher than toughness of the lower ring.   
     
     
         14 . The retainer ring according to  claim 13 , wherein a convex portion toward the polishing pad is formed on a lower surface of the outside ring. 
     
     
         15 . The retainer ring according to  claim 14 , wherein a distance between a tip of the convex portion and an end of the outside ring with no convex portion is below 30 μm. 
     
     
         16 . The retainer ring according to  claim 13 , wherein the inside ring is detachably attached to the outside ring. 
     
     
         17 . The retainer ring according to  claim 13 , wherein a material of the inside ring includes one or more of PPS, PEEK, PTFE, PP, PET, polycarbonate, and polyacetal. 
     
     
         18 . The retainer ring according to  claim 13 , wherein a material of the outside ring includes one or more of ceramic materials and metallic materials. 
     
     
         19 . The retainer ring according to  claim 19 , wherein surface roughness of a lower surface of the outside ring is a maximum of Ra 1.6 μm. 
     
     
         20 . The retainer ring according to  claim 10 , wherein Rockwell M hardness of the inside ring is in a range from a minimum of 70 to a maximum of 120. 
     
     
         21 . The retainer ring according to  claim 11 , wherein on a lower surface of the inside ring and a lower surface of the outside ring, a plurality of grooves extending in radial directions and communicating the inside ring and the outside ring are formed. 
     
     
         22 . A retainer ring for retaining a substrate to be polished, the retainer ring comprising:
 an inside ring arranged to enclose the substrate;   an outside ring arranged outside the inside ring, abrasion-resistant of the outside ring being higher than abrasion-resistant of the inside ring and the outside ring being harder than the inside ring;   wherein the outside ring and the inside ring are individually, vertically movable each other, and   the outside ring is either contact-less with the polishing pad, or is pressed onto the polishing pad with a force smaller than another force pressing the inside ring onto the polishing pad.   
     
     
         23 . The retainer ring according to  claim 22 , wherein a material of the inside ring includes one or more of PPS, PEEK, PTFE, PP, PET, polycarbonate, and polyacetal. 
     
     
         24 . The retainer ring according to  claim 22 , wherein a material of the outside ring includes one or more of ceramic materials and metallic materials. 
     
     
         25 . The retainer ring according to  claim 22 , wherein surface roughness of a lower surface of the outside ring is a maximum of Ra 1.6 μm. 
     
     
         26 . The retainer ring according to  claim 22 , wherein Rockwell M hardness of the inside ring is in a range from a minimum of 70 to a maximum of 120. 
     
     
         27 . The retainer ring according to  claim 22 , wherein on a lower surface of the inside ring and a lower surface of the outside ring, a plurality of grooves extending in radial directions and communicating the inside ring and the outside ring are formed. 
     
     
         28 . A substrate holding apparatus comprising:
 a top ring body holding a substrate; and   the retainer ring according to  claim 22 , the retainer ring being arranged to enclose the substrate held by the top ring body.   
     
     
         29 . A polishing apparatus comprising:
 a polishing pad; and   the substrate holding apparatus according to  claim 28 , the substrate holding apparatus pressing the substrate onto the polishing pad.