Retainer ring for polishing head

Abstract

In order to achieve the above object, the invention provides a retainer ring for polishing head includes: a base unit made of a highly rigid material, formed to have a ring-like shape, and supported on the polishing head side; and a resin unit in which a plurality of resin blocks are fixed to the lower surface of the base unit at almost the same intervals and which serves as a contact side to the polishing pad. Flow paths for the slurry are constituted by spaces between adjacent resin blocks and the lower surface of the base unit.

1 . A retainer ring for polishing head which, when a wafer held by a polishing head is pressed against a rotating polishing pad and polished while supplying slurry, is supported by the polishing head and surrounds a circumference of the wafer while being in contact with the polishing pad, comprising:
 a base unit made of a highly rigid material, formed to have a ring-like shape, and supported on the polishing head side; and a resin unit in which a plurality of resin blocks are fixed to the lower surface of the base unit at almost the same intervals and which serves as a contact side to the polishing pad, wherein flow paths for the slurry are constituted by spaces between adjacent resin blocks and the lower surface of the base unit.   
     
     
         2 . The retainer ring for polishing head according to  claim 1 , wherein
 a plurality of recessed portions are formed in the lower surface of the base unit, and the resin blocks are fitted in and bonded to, welded to, or screwed in the plurality of recessed portions, respectively, to fix the resin blocks to the lower surface of the base unit.   
     
     
         3 . The retainer ring for polishing head according to  claim 1 , wherein
 a plurality of tubular recessed portions are formed in the lower surface of the base unit, columnar projecting portions corresponding to the plurality of recessed portions are formed on the resin blocks, respectively, and the columnar projecting portions are pressed into and fitted in the tubular recessed portions, respectively, to fix the plurality of resin blocks to the lower surface of the base unit.   
     
     
         4 . The retainer ring for polishing head according to  claim 1 , wherein
 a plurality of dovetail-like trenches are formed at desired positions on the lower surface of the base unit, and the plurality of resin blocks are molded on the lower surface of the base unit in which the plurality of trenches are formed by resin casting using a mold to fix the plurality of resin blocks to the lower surface of the base unit.   
     
     
         5 . The retainer ring for polishing head according to  claim 1 , wherein
 intake holes communicating with the lower surface of the base unit are formed at desired positions in the base unit, respectively, and the plurality of resin blocks temporarily fixed to the lower surface of the base unit by arbitrary temporarily fixing means are fixed to the lower surface of the base unit by suction through the intake holes to fix the plurality of resin blocks to the lower surface of the base unit.   
     
     
         6 . A retainer ring for polishing head which, when a wafer held by a polishing head is pressed against a rotating polishing pad and polished while supplying slurry, is supported by the polishing head and surrounds a circumference of the wafer while being in contact with the polishing pad, comprising:
 a base-unit-equivalent portion made of a highly rigid material, formed to have a ring-like shape, and integrally formed with a retainer ring holder arranged on the polishing head; and a resin unit in which a plurality of resin blocks are fixed to the lower surface of the base-unit-equivalent portion at almost the same intervals and which serves as a contact side to the polishing pad, wherein flow paths for the slurry are constituted by spaces between adjacent resin blocks and the lower surface of the base-unit-equivalent portion.   
     
     
         7 . The retainer ring for polishing head according to  claim 6 , wherein
 a plurality of recessed portions are formed in the lower surface of the base-unit-equivalent portion, and the resin blocks are fitted in and bonded to, welded to, or screwed in the plurality of recessed portions, respectively, to fix the resin blocks to the lower surface of the base-unit-equivalent portion.   
     
     
         8 . The retainer ring for polishing head according to  claim 6 , wherein
 a plurality of tubular recessed portions are formed in the lower surface of the base-unit-equivalent portion, columnar projecting portions corresponding to the plurality of recessed portions are formed on the resin blocks, respectively, and the columnar projecting portions are pressed into and fitted in the tubular recessed portions, respectively, to fix the plurality of resin blocks to the lower surface of the base-unit-equivalent portion.   
     
     
         9 . The retainer ring for polishing head according to  claim 6 ,  7 , or  8 , wherein
 an elastic sheet stretched on an upper surface side of the wafer inside the retainer ring has a peripheral portion held between the base-unit-equivalent portion and the resin unit.   
     
     
         10 . A retainer ring for polishing head which, when a wafer held by a polishing head is pressed against a rotating polishing pad to polish the wafer, is supported by the polishing head and surrounds a circumference of the wafer while being in contact with the polishing pad, comprising:
 a base unit made of a highly rigid material, formed to have a ring-like shape, and supported on the polishing head side; and a resin unit in which a plurality of resin blocks are fixed to the lower surface of the base unit at almost the same intervals and which serves as a contact side to the polishing pad, wherein the resin unit is designed to be replaceable by canceling a fixing state of the resin unit to the lower surface of the base unit.   
     
     
         11 . The retainer ring for polishing head according to  claim 10 , wherein
 a push-out hole which pushes the resin unit out to remove the resin unit from the lower surface of the base unit is formed in the base unit in advance, and when a fixing state of the resin unit to the lower surface of the base unit is to be canceled, the resin unit is designed to be removed by a rod-like member from the lower surface of the base unit through the push-out hole.   
     
     
         12 . The retainer ring for polishing head according to  claim 10 , wherein
 force in a direction opposing the direction of the force acting on the resin blocks in a normal operation in which the polishing head rotates is applied to the resin blocks to slide the resin blocks to make it possible to remove the resin unit from the lower surface of the base unit, and when the fixing state of the resin unit to the lower surface of the base unit is to be canceled, the force in the opposite direction is applied to the resin blocks to remove the resin blocks from the lower surface of the base unit.   
     
     
         13 . The retainer ring for polishing head according to  claim 10 , wherein
 a lock member which locks fixing states of the resin blocks to the lower surface of the base unit extends from the base unit to the resin unit side, and when a fixing state of the resin unit to the lower surface of the base unit is to be canceled, the lock states of the resin blocks set by the lock member are canceled to remove the resin blocks from the lower surface of the base unit.   
     
     
         14 . The retainer ring for polishing head according to  claim 1 ,  2 ,  3 ,  4 ,  5 ,  6 ,  7 ,  8 ,  9 ,  10 ,  11 ,  12 , or  13 , wherein
 the highly rigid material is a metal, a ceramic, or a highly rigid engineering plastic, and the resin material is an engineering plastic containing polyphenylenesulfide (PPS) and polyetheretherketone (PEEK).