Polishing head and polishing apparatus

Abstract

The present invention is a polishing head having at least: an approximately discoid mid plate; a rubber film covering at least a lower face portion and a side face portion of the mid plate; and a space portion surrounded by the mid plate and the rubber film; in which pressure of the space portion can be changed by a pressure adjustment mechanism, a back surface of a workpiece is held on a lower face portion of the rubber film and a front surface of the workpiece is brought into sliding contact with a polishing pad attached onto a turn table for performing polishing; wherein the mid plate and the rubber film do not contact one another to have a gap at least throughout a whole of the lower face portion of the mid plate. As a result, there is provided a polishing head etc by a rubber chuck method in which a uniform polishing load is applied over the workpiece without influence of stiffness or flatness of the mid plate.

1 . A polishing head having at least: an approximately discoid mid plate; a rubber film covering at least a lower face portion and a side face portion of the mid plate; and a space portion surrounded by the mid plate and the rubber film; in which pressure of the space portion can be changed by a pressure adjustment mechanism, a back surface of a workpiece is held on a lower face portion of the rubber film and a front surface of the workpiece is brought into sliding contact with a polishing pad attached onto a turn table for performing polishing; wherein
 the mid plate and the rubber film do not contact one another to have a gap at least throughout a whole of the lower face portion of the mid plate.   
     
     
         2 . The polishing head according to  claim 1 , wherein the gap between the mid plate and the rubber film is less than 1 mm. 
     
     
         3 . The polishing head according to  claim 1 , wherein the mid plate and the rubber film also do not contact one another to have a gap throughout a whole of the side face portion of the mid plate. 
     
     
         4 - 7 . (canceled) 
     
     
         8 . The polishing head according to  claim 2 , wherein the mid plate and the rubber film also do not contact one another to have a gap throughout a whole of the side face portion of the mid plate. 
     
     
         9 . The polishing head according to  claim 1 , wherein an inner diameter of the portion covering the side face portion of the mid plate in the rubber film is larger than a flatness quality area of the workpiece. 
     
     
         10 . The polishing head according to  claim 2 , wherein an inner diameter of the portion covering the side face portion of the mid plate in the rubber film is larger than a flatness quality area of the workpiece. 
     
     
         11 . The polishing head according to  claim 3 , wherein an inner diameter of the portion covering the side face portion of the mid plate in the rubber film is larger than a flatness quality area of the workpiece. 
     
     
         12 . The polishing head according to claim  4 , wherein an inner diameter of the portion covering the side face portion of the mid plate in the rubber film is larger than a flatness quality area of the workpiece. 
     
     
         13 . The polishing head according to  claim 1 , wherein the polishing head has a backing pad on the face of the rubber film, the face holding the workpiece. 
     
     
         14 . The polishing head according to  claim 2 , wherein the polishing head has a backing pad on the face of the rubber film, the face holding the workpiece. 
     
     
         15 . The polishing head according to  claim 3 , wherein the polishing head has a backing pad on the face of the rubber film, the face holding the workpiece. 
     
     
         16 . The polishing head according to claim  4 , wherein the polishing head has a backing pad on the face of the rubber film, the face holding the workpiece. 
     
     
         17 . The polishing head according to claim  5 , wherein the polishing head has a backing pad on the face of the rubber film, the face holding the workpiece. 
     
     
         18 . The polishing head according to claim  6 , wherein the polishing head has a backing pad on the face of the rubber film, the face holding the workpiece. 
     
     
         19 . The polishing head according to claim  7 , wherein the polishing head has a backing pad on the face of the rubber film, the face holding the workpiece. 
     
     
         20 . The polishing head according to  claim 8 , wherein the polishing head has a backing pad on the face of the rubber film, the face holding the workpiece. 
     
     
         21 . The polishing head according to  claim 9 , wherein a diameter of the backing pad is larger than that of the workpiece. 
     
     
         22 . A polishing apparatus used for polishing a surface of a workpiece at least comprising: a polishing pad attached onto a turn table; a polishing agent supply mechanism for providing a polishing agent to the polishing pad; and a polishing head for holding the workpiece, which is the polishing head according to  claim 1 .