Method for manufacturing polishing pad

Abstract

A method for manufacturing a polishing pad, which may be laminated, with a small number of manufacturing steps, high productivity and no peeling between a polishing layer and a cushion layer includes preparing a cell-dispersed urethane composition by a mechanical foaming method; continuously discharging the cell-dispersed urethane composition onto a face material, while feeding the face material; laminating another face material on the cell-dispersed urethane composition; curing the cell-dispersed urethane composition, while controlling its thickness to be uniform, so that a polishing layer including a polyurethane foam is formed; cutting the polishing layer parallel to the face into two pieces so that two long polishing layers each including the polishing layer and the face material are simultaneously formed; and cutting the long polishing layers to produce the polishing pad.

1 . A method for manufacturing a polishing pad, comprising the steps of:
 preparing a cell-dispersed urethane composition by a mechanical foaming method;   continuously discharging the cell-dispersed urethane composition onto a face material, while feeding the face material;   laminating another face material on the cell-dispersed urethane composition;   curing the cell-dispersed urethane composition, while controlling its thickness to be uniform, so that a polishing layer comprising a polyurethane foam is formed;   cutting the polishing layer parallel to the face into two pieces so that two long polishing layers each comprising the polishing layer and the face material are simultaneously formed; and   cutting the long polishing layers.   
     
     
         2 . A polishing pad manufactured by the method according to  claim 1 . 
     
     
         3 . A method for manufacturing a laminated polishing pad, comprising the steps of:
 preparing a cell-dispersed urethane composition by a mechanical foaming method;   continuously discharging the cell-dispersed urethane composition onto a cushion layer, while feeding the cushion layer;   laminating another cushion layer on the cell-dispersed urethane composition;   curing the cell-dispersed urethane composition, while controlling its thickness to be uniform, so that a polishing layer comprising a polyurethane foam is formed;   cutting the polishing layer parallel to the face into two pieces so that two long laminated sheets each comprising the polishing layer and the cushion layer are simultaneously formed; and   cutting the long laminated sheets.   
     
     
         4 . A laminated polishing pad manufactured by the method according to  claim 3 . 
     
     
         5 . A method for manufacturing a polishing pad, comprising the steps of:
 preparing a cell-dispersed urethane composition by a mechanical foaming method;   providing spacers on both ends parts and/or an inner site of a face material, while feeding the face material;   continuously discharging said cell-dispersed urethane composition onto a part of said face material where the spacer is not provided;   laminating another face material on said discharged cell-dispersed urethane composition;   curing the cell-dispersed urethane composition, while controlling its thickness to be uniform, so that a long polishing layer comprising a polyurethane foam is formed; and   cutting the long polishing layer.   
     
     
         6 . The method according to  claim 5 , wherein the spacer comprises a thermoplastic resin or a thermosetting resin. 
     
     
         7 . The method according to  claim 5 , wherein the spacer provided on the inner site has a light transmittance of at least 20% throughout the wavelength range of 400 nm to 700 nm. 
     
     
         8 . The method according to  claim 5 , wherein the spacer comprises a polyurethane foam whose composition is the same as that of said cell-dispersed urethane composition. 
     
     
         9 . The method according to  claim 5 , wherein the spacer provided on the inner site is a laminate comprising at least two peelable resin sheets. 
     
     
         10 . A polishing pad manufactured by the method according to  claim 5 . 
     
     
         11 . A method for manufacturing a laminated polishing pad, comprising the steps of:
 preparing a cell-dispersed urethane composition by a mechanical foaming method;   providing spacers on both ends parts and/or an inner site of a cushion layer, while feeding the cushion layer;   continuously discharging said cell-dispersed urethane composition onto a part of said cushion layer where the spacer is not provided;   laminating a face material on said discharged cell-dispersed urethane composition;   curing the cell-dispersed urethane composition to form a polishing layer comprising a polyurethane foam, while controlling its thickness to be uniform, so that a long laminated sheet is formed; and   cutting the long laminated sheet.   
     
     
         12 . The method according to  claim 11 , wherein the spacer comprises a thermoplastic resin or a thermosetting resin. 
     
     
         13 . The method according to  claim 11 , wherein the spacer provided on the inner site is inserted in a through hole of the cushion layer and provided so as to protrude from the cushion layer. 
     
     
         14 . The method according to  claim 13 , wherein the spacer provided on the inner site has a light transmittance of at least 20% over the wavelength range of 400 nm to 700 nm. 
     
     
         15 . The method according to  claim 11 , wherein the spacer comprises a polyurethane foam whose composition is the same as that of said cell-dispersed urethane composition. 
     
     
         16 . The method according to  claim 11 , wherein the spacer provided on the inner site is a laminate comprising at least two peelable resin sheets. 
     
     
         17 . A laminated polishing pad manufactured by the method according to  claim 11 . 
     
     
         18 . A method for manufacturing a polishing pad, comprising the steps of:
 preparing a cell-dispersed urethane composition by a mechanical foaming method;   continuously or intermittently discharging a light transmitting region-forming material onto a prescribed site of a face material, while feeding the face material;   continuously discharging said cell-dispersed urethane composition onto a part of said face material where the light transmitting region-forming material is not provided;   laminating another face material on said discharged light transmitting region-forming material and cell-dispersed urethane composition;   curing the light transmitting region-forming material and the cell-dispersed urethane composition, while controlling their thickness to be uniform, so that a long polishing layer comprising a light transmitting region and a polishing region integrated therewith is formed; and   cutting the long polishing layer.   
     
     
         19 . The method according to  claim 18 , wherein said light transmitting region-forming material has a viscosity of 1 to 30 Pa·s when discharged. 
     
     
         20 . The method according to  claim 18 , wherein said cell-dispersed urethane composition has a viscosity of 1 to 20 Pa·s when discharged. 
     
     
         21 . The method according to  claim 18 , wherein said light transmitting region comprises a thermosetting resin. 
     
     
         22 . The method according to  claim 21 , wherein said thermosetting resin is a polyurethane resin. 
     
     
         23 . A polishing pad manufactured by the method according to  claim 18 . 
     
     
         24 . A method for manufacturing a laminated polishing pad, comprising the steps of:
 preparing a cell-dispersed urethane composition by a mechanical foaming method;   discharging a light transmitting region-forming material such that the material is deposited in and on through holes, while feeding a cushion layer having continuously or intermittently provided through holes;   continuously discharging said cell-dispersed urethane composition onto a part of said cushion layer where the light transmitting region-forming material is not provided;   laminating a face material on the discharged light transmitting region-forming material and cell-dispersed urethane composition;   curing the light transmitting region-forming material and the cell-dispersed urethane composition, while controlling their thickness to be uniform, so that a long laminated sheet comprising a light transmitting region and a polishing region integrated therewith is formed; and   cutting the long laminated sheet.   
     
     
         25 . The method according to  claim 24 , wherein said light transmitting region-forming material has a viscosity of 1 to 30 Pa·s when discharged. 
     
     
         26 . The method according to  claim 24 , wherein said cell-dispersed urethane composition has a viscosity of 1 to 20 Pa·s when discharged. 
     
     
         27 . The method according to  claim 24 , wherein said light transmitting region comprises a thermosetting resin. 
     
     
         28 . The method according to  claim 27 , wherein said thermosetting resin is a polyurethane resin. 
     
     
         29 . A laminated polishing pad manufactured by the method according to  claim 24 . 
     
     
         30 . A method for manufacturing a groove-carrying polishing pad, comprising the steps of:
 preparing a cell-dispersed urethane composition by a mechanical foaming method;   continuously discharging the cell-dispersed urethane composition onto a conveyor belt having a recessed structure;   laminating a face material on the discharged cell-dispersed urethane composition;   curing the cell-dispersed urethane composition, while controlling its thickness to be uniform, so that a groove-carrying long polishing layer comprising a polyurethane foam is formed;   separating the groove-carrying long polishing layer from the conveyor belt; and   cutting the groove-carrying long polishing layer.   
     
     
         31 . A method for manufacturing a groove-carrying polishing pad, comprising the steps of:
 preparing a cell-dispersed urethane composition by a mechanical foaming method;   continuously discharging the cell-dispersed urethane composition onto a release sheet having a recessed structure, while feeding the release sheet;   laminating a face material on the discharged cell-dispersed urethane composition;   curing the cell-dispersed urethane composition, while controlling its thickness to be uniform, so that a groove-carrying long polishing layer comprising a polyurethane foam is formed;   separating the release sheet from the groove-carrying long polishing layer; and   cutting the groove-carrying long polishing layer.   
     
     
         32 . A method for manufacturing a groove-carrying laminated polishing pad, comprising the steps of:
 preparing a cell-dispersed urethane composition by a mechanical foaming method;   continuously discharging the cell-dispersed urethane composition onto a conveyor belt having a recessed structure;   laminating a cushion layer on the discharged cell-dispersed urethane composition;   curing the cell-dispersed urethane composition, while controlling its thickness to be uniform, so that a groove-carrying long polishing layer comprising a polyurethane foam is formed and then a groove-carrying long laminated sheet is formed;   separating the groove-carrying long laminated sheet from the conveyor belt; and   cutting the groove-carrying long laminated sheet.   
     
     
         33 . A method for manufacturing a groove-carrying laminated polishing pad, comprising the steps of:
 preparing a cell-dispersed urethane composition by a mechanical foaming method;   continuously discharging the cell-dispersed urethane composition onto a release sheet having a recessed structure, while feeding the release sheet;   laminating a cushion layer on the discharged cell-dispersed urethane composition;   curing the cell-dispersed urethane composition, while controlling its thickness to be uniform, so that a groove-carrying long polishing layer comprising a polyurethane foam is formed and then a groove-carrying long laminated sheet is formed;   separating the release sheet from the groove-carrying long laminated sheet; and   cutting the groove-carrying long laminated sheet.   
     
     
         34 . A groove-carrying polishing pad manufactured by the method according to  claim 30  or  31 . 
     
     
         35 . A groove-carrying laminated polishing pad manufactured by the method according to  claim 32  or  33 . 
     
     
         36 . A method for manufacturing a semiconductor device, comprising the step of polishing a surface of a semiconductor wafer with the polishing pad according to  claim 2 ,  10  or  23 , the laminated polishing pad according to  claim 4 ,  17  or  29 , the groove-carrying polishing pad according to  claim 34 , or the groove-carrying laminated polishing pad according to  claim 35 .