Polishing head and polishing processing device

Abstract

A pressing mechanism of a polishing head includes a first pressing body configured so as to include a first airbag and a first pressure disc formed so that a portion near the center of a contact surface which comes into contact with an elastic body is convex-shaped towards the elastic body; and a second pressing body, which is formed as a cylinder having the first pressure disc disposed on the inner circumferential side thereof, and which is configured so as to include a second airbag and a second pressure disc formed so that a portion near the outer edge of a contact surface which comes into contact with the elastic body is concave-shaped towards the elastic body.

1 . A polishing head to be provided in a polishing processing device having a polishing surface which horizontally rotates, comprising:
 a holding unit configured to hold a substrate to be subjected to polishing processing in such a manner that a surface to be polished of the substrate is slidably brought into contact with the polishing surface; and   a pressing unit configured to press the substrate held by the holding unit from a rear surface side of the surface to be polished toward the polishing surface,   wherein the pressing unit comprises a pressing body, an elastic body disposed to come into contact with the pressing body, and a fluid supply unit configured to supply the pressure fluid to the pressing body, wherein the pressing body is configured such that pressure fluid is sealed to the pressing body to generate pressing force in accordance with quantity of the pressure fluid toward the rear surface side of the substrate,   wherein the pressing body comprises a first pressing body which is cylindrically-shaped and a second pressing body which is annularly-shaped disposed to surround the first pressing body,   wherein the first pressing body is formed so that a portion near a center of a contact surface which comes into contact with the elastic body is convex-shaped toward the elastic body side, and the second pressing body is formed so that a portion which is outer peripheral side of the contact surface which comes into contact with the elastic body is convex-shaped toward the elastic body side, and   wherein the pressing force, generated by the pressure fluid sealed in the first pressing body and the second pressing body separately and respectively, is respectively applied to the rear surface side of the substrate held by the holding unit through the elastic body.   
     
     
         2 . The polishing head according to  claim 1  further comprises a driving unit for horizontally rotating the holding unit,
 wherein the second pressing body is connected to move according to the holding unit, 
 wherein the first pressing body is connected to move according to the second pressing body, and 
 wherein the first pressing body and the second pressing body are respectively connected to connection destinations vertically movably such that the respective pressing force applied to the rear surface side of the substrate changes before and during horizontal rotation. 
 
     
     
         3 . The polishing head according to claim, wherein the pressing unit further comprising:
 an elastic cylindrical body, an inner bottom surface of which comes into contact with the elastic body, and an outer bottom surface of which comes into contact with the rear surface side of the substrate; and   a top ring disposed between an inner peripheral surface of the elastic cylindrical body and an outer peripheral surface of the elastic body and holds the elastic cylindrical body,   wherein the top ring is connected to move according to the holding unit.   
     
     
         4 . The polishing head according to  claim 3 , wherein the holding unit is configured to connect to the top ring at a position at which floating of the elastic cylindrical body from the substrate is suppressed. 
     
     
         5 . The polishing head according to  claim 3 , wherein the outer peripheral surface of the top ring is brought into close contact with the inner peripheral surface of the elastic cylindrical body to hold the elastic cylindrical body, thereby the elastic cylindrical body moves according to the top ring. 
     
     
         6 . The polishing head according to  claim 1 , wherein the pressing body comprises an airbag in which the pressure fluid is sealed to expand and generates pressing force in accordance with quantity of the pressure fluid. 
     
     
         7 . The polishing head according to  claim 1 , wherein a size of a surface of the elastic body, which applies the pressing force from the rear surface side of the surface to be polished, is smaller than a size of the surface to be polished. 
     
     
         8 . The polishing head according to  claim 3 ,
 wherein a side of the elastic cylindrical body is formed in a bellows shape and one end of the side formed in the bellows shape is held by the top ring, and   with expansion and contraction of the side formed in the bellows shape starting from one end of the side held by the top ring, an outer bottom surface of the elastic cylindrical body which comes into contact with the rear surface of the substrate horizontally moves up or moves down corresponding to the pressing force.   
     
     
         9 . A polishing processing device comprising:
 a polishing table having a circular or generally circular polishing surface, a polishing head configured to hold a substrate to be subjected to polishing processing to slidably bring a circular surface to be polished of the substrate into contact with the polishing surface, and   a driving unit configured to horizontally rotate at least one of the polishing head and the polishing table,   wherein the polishing table is configured such that a radius of the polishing surface is larger than a diameter of the surface to be polished of the substrate,   wherein the polishing head comprises:   a holding unit configured to hold the surface to be polished of the substrate to be slidably brought into contact with the polishing surface,   a pressing body, in which pressure fluid is sealed to generate pressing force in accordance with quantity of the pressure fluid toward the rear surface side of the substrate, an elastic body disposed to come into contact with the pressing body, and a fluid supply unit configured to supply pressure fluid to the pressing body,   wherein the pressing body comprises a first pressing body which is cylindrically-shaped and a second pressing body which is annularly-shaped disposed to surround the first pressing body,   wherein the first pressing body is formed so that a portion near a center of a contact surface which comes into contact with the elastic body is convex-shaped toward the elastic body,   wherein the second pressing body is formed so that a portion which is outer peripheral side of the contact surface which comes into contact with the elastic body is convex-shaped toward the elastic body side, and   a pressing unit configured to respectively apply the pressing force, generated by the pressure fluid sealed in the first pressing body and the second pressing body separately and respectively, to the rear surface side of the substrate held by the holding unit through the elastic body.