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US5542874A Expired / Lapsed US ⏱️ 0.0 years remaining

Wafer polishing apparatus

Assignee: Renesas Electronics Corp
•
Filing: 1994-09-16
•
Granted: 1996-08-06
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Expires: 2014-09-16
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Abstract

Abstract A wafer polishing apparatus has a wafer chuck for holding a wafer with a surface to be polished directed upward, the wafer chuck being rotatable by a wafer chuck rotation motor; a pair of nozzles for supplying slurries used as polishing solutions to the wafer; and a polishing head for holding a polishing cloth pad which is smaller in diameter than the wafer. The polishing head is rotated in the same direction as the wafer chuck by a polishing head rotation motor and is also reciprocally moved along the surface of the wafer to be polished by an arm driving motor. The wafer polishing apparatus also has a polishing head load adjusting air cylinder for pressing the polishing cloth pad against the wafer by way of the polishing head.

Inventors

  • 👤 Shinichi Chikaki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 17:36
CPC Classifications
B; B24; B24B; B24B37/00; B24B37/04; B24B37/07; B24B37/10; B24B37/105; B24B41/00; B24B41/04

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 122 words
A wafer polishing apparatus comprising: a wafer chuck for holding a wafer with a surface to be polished thereof being directed upward; first drive means for rotating said wafer chuck; polishing solution supply means for supplying a polishing solution to the wafer held by said wafer chuck; a polishing head which is smaller in diameter than the wafer; a polishing pad which is smaller in diameter than the wafer, said polished pad being attached to said polishing head; second drive means for rotating said polishing head; reciprocating means for reciprocally moving said polishing head on said surface to be polished; and pressing means for pressing said polishing pad against a wafer held by said wafer chuck by way of said polishing head.
Claim 2
Dependent Claim 122 words
A wafer polishing apparatus comprising: a wafer chuck for holding a wafer with a surface to be polished thereof being directed upward; first drive means for rotating said wafer chuck; polishing solution supply means for supplying a polishing solution to the wafer held by said wafer chuck; a polishing head which is smaller in diameter than the wafer; a polishing pad which is smaller in diameter than the wafer, said polished pad being attached to said polishing head; second drive means for rotating said polishing head; reciprocating means for reciprocally moving said polishing head on said surface to be polished; and pressing means for pressing said polishing pad against a wafer held by said wafer chuck by way of said polishing head.
Claim 3
Dependent Claim 25 words
A wafer polishing apparatus according to claim 1 wherein said polishing pad has a diameter substantially equal to an interval of undulations of the wafer.
Claim 4
Dependent Claim 25 words
A wafer polishing apparatus according to claim 1 comprising a plurality of polishing heads for holding a corresponding plurality of polishing pads of different types.
Claim 5
Dependent Claim 25 words
A wafer polishing apparatus according to claim 2 comprising a plurality of polishing heads for holding a corresponding plurality of polishing pads of different types.

References Cited (Backward Citations)

US4128968A Cited
US4232485A Cited
US4693036A Cited
US4956944A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-08-06 2000-02-05 2000-08-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-08-06 2004-02-05 2004-08-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-08-06 2008-02-05 2008-08-06 $7700.00 Window Closed / Lapsed

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