# US 6,293,858 B1 · Polishing device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,293,858 B1 - Document ID: US6293858B1 - Status: Granted - Kind: B1 - Application number: 09/445,220 - Filed: 1999-12-06 - Granted: 2001-09-25 - Earliest claimed: 1998-04-06 - Assignees: Ebara Corporation - Inventors: Norio Kimura; Toru Maruyama; Shunichiro Kojima; Seiji Katsuoka; Shin Ohwada - Web page: https://patentgrep.com/patent/US6293858B1 ## CPC - B24B 37/32: Retaining rings - B24B 49/16: taking regard of the load - B24B: MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING (grinding of gear teeth B23F, of screw-threads B23G1/36; by electro-erosion B23H; abrasive or related blasting B24C; tools for grinding, buffing or sharpening B24D; polishing compositions C09G1/00; abrasives C09K3/14; electrolytic etching or polishing C25F3/00; grinding arrangements for use on assembled railway tracks E01B31/17); DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS ## Abstract A polishing apparatus for polishing a workpiece such as a semiconductor wafer to a flat mirror finish includes a turntable with a polishing cloth mounted on an upper surface thereof and a top ring for polishing a semiconductor wafer to a flat mirror finish by placing the semiconductor wafer between the turntable and the top ring and pressing the semiconductor wafer under a certain pressing force. A presser ring is vertically movably provided around the top ring. A pressing device presses the presser ring against the polishing cloth under a variable pressing force, and the presser ring is supported by the top ring through a bearing. ## Claims ### Claim 1 A polishing apparatus comprising: a turntable having a polishing cloth on an upper surface thereof; a top ring to press under a certain pressing force a workpiece, to be positioned between said turntable and said top ring, toward said turntable to thus polish the workpiece; a presser ring vertically movably provided around said top ring; a bearing supporting said presser ring on said top ring; and a pressing device to press said presser ring against said polishing cloth under a variable pressing force. ### Claim 2 (depends on 1) An apparatus as claimed in claim 1, wherein said top ring has a recess for accommodating the workpiece. ### Claim 3 (depends on 1) An apparatus as claimed in claim 1, wherein said bearing comprises an integral bearing supporting said presser ring to enable relative rotation between said top ring and said presser ring, and also to enable vertical movement of said presser ring with respect to said top ring. ### Claim 4 (depends on 1) An apparatus as claimed in claim 1, wherein said bearing comprises a rotation support bearing supporting said presser ring to enable relative rotation between said top ring and said presser ring, and a vertical movement support bearing to enable vertical movement of said presser ring with respect to said top ring. ### Claim 5 (depends on 1) An apparatus as claimed in claim 1, further comprising a labyrinth to prevent foreign matter from entering said bearing. ### Claim 6 (depends on 1) An apparatus as claimed in claim 1, further comprising a cleaning liquid supply to supply a cleaning liquid to a gap between said presser ring and said top ring. ### Claim 7 A polishing apparatus comprising: a turntable having a polishing cloth on an upper surface thereof; a top ring to press under a certain pressing force a workpiece, to be positioned between said turntable and said top ring, toward said turntable to thus polish the workpiece; a presser ring vertically movably provided around said top ring; a pressing device to press said presser ring against said polishing cloth under a variable pressing force; and an abrasive liquid supply to supply abrasive liquid inside of said presser ring, said abrasive liquid supply including a cleaning device to allow abrasive liquid flowing through said abrasive liquid supply to be washed away. ### Claim 8 (depends on 7) An apparatus as claimed in claim 7, wherein said top ring has a recess for accommodating the workpiece. ### Claim 9 (depends on 7) An apparatus as claimed in claim 7, wherein said abrasive liquid supply comprises an abrasive liquid supply hole passing through a wall of said presser ring, an abrasive liquid supply tube connected to said abrasive liquid supply hole, and an abrasive liquid supply source connected to said abrasive liquid supply tube. ### Claim 10 (depends on 9) An apparatus as claimed in claim 9, further comprising a cleaning liquid supply device to supply cleaning liquid to a gap between said top ring and said presser ring, said cleaning liquid supply device including a cleaning liquid supply hole located above abrasive liquid supply hole of said abrasive liquid supply. ### Claim 11 (depends on 7) An apparatus as claimed in claim 7, further comprising a cleaning liquid supply device to supply cleaning liquid to a gap between said top ring and said presser ring. ### Claim 12 A polishing apparatus comprising: a turntable having a polishing cloth on an upper surface thereof; a top ring to press under a certain pressing force a workpiece, to be positioned between said turntable and said top ring, toward said turntable to thus polish the workpiece; a presser ring vertically movably provided around said top ring; a pressing device to press said presser ring against said polishing cloth under a variable pressing force; and an abrasive liquid supply to supply abrasive liquid inside of said presser ring, said abrasive liquid supply comprising an abrasive liquid supply hole passing through a wall of said presser ring, an abrasive liquid supply tube connected to said abrasive liquid supply hole, and an abrasive liquid supply source connected to said abrasive liquid supply tube. ### Claim 13 (depends on 12) An apparatus as claimed in claim 12, wherein said top ring has a recess for accommodating the workpiece. ### Claim 14 (depends on 12) An apparatus as claimed in claim 12, further comprising a cleaning liquid supply device to supply cleaning liquid to a gap between said top ring and said presser ring, said cleaning liquid supply device including a cleaning liquid supply hole located above abrasive liquid supply hole of said abrasive liquid supply. ### Claim 15 (depends on 12) An apparatus as claimed in claim 12, wherein said top ring has a recess for accommodating the workpiece. ### Claim 16 A polishing apparatus comprising: a turntable having a polishing cloth on an upper surface thereof; a top ring to press under a certain pressing force a workpiece, to be positioned between said turntable and said top ring, toward said turntable to thus polish the workpiece; a presser ring vertically movably provided around said top ring; a pressing device to press said presser ring against said polishing cloth under a variable pressing force; an abrasive liquid supply to supply abrasive liquid inside of said presser ring; and a cleaning liquid supply device to supply cleaning liquid to a gap between said top ring and said presser ring. ### Claim 17 A polishing apparatus comprising: a table having a polishing surface thereon; a top ring to press under a certain pressing force a workpiece, to be positioned between said table and said top ring, toward said table to thus polish the workpiece; a presser ring vertically movably provided around said top ring; a bearing supporting said presser ring on said top ring; and a pressing device to press said presser ring against said polishing surface under a variable pressing force. ### Claim 18 A polishing apparatus comprising: a table having a polishing surface thereon; a top ring to press under a certain pressing force a workpiece, to be positioned between said table and said top ring, toward said table to thus polish the workpiece; a presser ring vertically movably provided around said top ring; a pressing device to press said presser ring against said polishing surface under a variable pressing force; and an abrasive liquid supply to supply abrasive liquid inside of said presser ring, said abrasive liquid supply including a cleaning device to allow abrasive liquid flowing through said abrasive liquid supply to be washed away. ### Claim 19 A polishing apparatus comprising: a table having a polishing surface thereon; a top ring to press under a certain pressing force a workpiece, to be positioned between said table and said top ring, toward said table to thus polish the workpiece; a presser ring vertically movably provided around said top ring; a pressing device to press said presser ring against said polishing surface under a variable pressing force; and an abrasive liquid supply to supply abrasive liquid inside of said presser ring, said abrasive liquid supply comprising an abrasive liquid supply hole passing through a wall of said presser ring, an abrasive liquid supply tube connected to said abrasive liquid supply hole, and an abrasive liquid supply source connected to said abrasive liquid supply tube. ### Claim 20 A polishing apparatus comprising: a table having a polishing surface thereon; a top ring to press under a certain pressing force a workpiece, to be positioned between said table and said top ring, toward said table to thus polish the workpiece; a presser ring vertically movably provided around said top ring; a pressing device to press said presser ring against said polishing surface under a variable pressing force; an abrasive liquid supply to supply abrasive liquid inside of said presser ring; and a cleaning liquid supply device to supply cleaning liquid to a gap between said top ring and said presser ring.