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US5957757A Expired / Lapsed US ⏱️ 0.0 years remaining

Conditioning CMP polishing pad using a high pressure fluid

Assignee: Bell Semiconductor LLC
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Filing: 1997-10-30
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Granted: 1999-09-28
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Expires: 2017-10-30
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Abstract

Abstract The present invention advantageously provides a method for conditioning a polishing pad used for chemical mechanical polishing of a semiconductor wafer surface. The method involves directing a fluid at a relatively high pressure toward the surface of the pad, thereby roughening the surface of the pad and removing particles embedded in pores of the pad. This process provides for uniform conditioning across the surface of the pad and excludes the use of particles which might become disposed on the pad, unlike some other conventional conditioning methods. The exclusion of abrasive particles prevents scratching of wafers which may subsequently undergo CMP using the polishing pad. The conditioning fluid hereof may, among other things, be a typical CMP slurry or variation thereof, or may be deionized water.

Inventors

  • 👤 Michael J. Berman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 15:26
CPC Classifications
B; B24; B24B; B24B53/00; B24B53/017; B08; B08B; B08B3/00; B08B3/02

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 99 words
A method for conditioning a polishing pad, comprising: polishing a semiconductor topography with a polishing surface of the polishing pad and an amount of a chemical mechanical polishing slurry; diluting another amount of said chemical mechanical polishing slurry; adjusting the pH of the diluted chemical mechanical polishing slurry back to its prediluted value to create a conditioning fluid; arranging a conduit a spaced distance above the polishing surface; and forwarding said conditioning fluid through the conduit and upon the polishing surface at a pressure sufficient to dislodge particles entrained within pores of the polishing surface resulting from said polishing.
Claim 2
Independent Claim 99 words
A method for conditioning a polishing pad, comprising: polishing a semiconductor topography with a polishing surface of the polishing pad and an amount of a chemical mechanical polishing slurry; diluting another amount of said chemical mechanical polishing slurry; adjusting the pH of the diluted chemical mechanical polishing slurry back to its prediluted value to create a conditioning fluid; arranging a conduit a spaced distance above the polishing surface; and forwarding said conditioning fluid through the conduit and upon the polishing surface at a pressure sufficient to dislodge particles entrained within pores of the polishing surface resulting from said polishing.
Claim 3
Dependent Claim 22 words
The method of claim 1, wherein said polishing comprises chemical mechanical polishing performed prior to arranging the conduit and forwarding the fluid.
Claim 4
Dependent Claim 17 words
The method of claim 1, wherein said pressure ranges from about 75 psig to over 2,000 psig.
Claim 5
Dependent Claim 36 words
The method of claim 1, further comprising positioning said polishing pad on a rotating device such that the polishing surface faces upward, and thereby rotating said polishing pad concurrent with the step of forwarding said fluid.
Claim 6
Dependent Claim 31 words
The method of claim 1, wherein the step of forwarding said fluid comprises pumping said fluid out through an end of said conduit, said end being disposed above said polishing surface.
Claim 7
Dependent Claim 43 words
The method of claim 1, further comprising maintaining said conduit in a substantially immobile position above said polishing surface and rotating said polishing pad concurrent with the step of directing said fluid such that said fluid contacts various regions of said polishing surface.
Claim 8
Dependent Claim 37 words
The method of claim 1, further comprising moving said conduit across a horizontal plane above said polishing surface concurrent with the step of forwarding said fluid such that said fluid contacts various regions of said polishing surface.
Claim 9
Dependent Claim 23 words
The method of claim 6 or 7, wherein said fluid is forwarded toward said polishing surface via a nozzle attached to said conduit.
Claim 10
Dependent Claim 23 words
The method of claim 1, wherein said chemical mechanical polishing slurry comprises particles selected from the group consisting of silica, alumina, and ceria.
Claim 11
Dependent Claim 25 words
The method of claim 1, wherein said pressure is sufficient to force particles from pores of said polishing surface and away from said polishing surface.
Claim 12
Dependent Claim 22 words
The method of claim 1, wherein said diluting comprises diluting said another amount of said chemical mechanical polishing slurry with deionized water.
Claim 13
Dependent Claim 16 words
The method of claim 1, wherein said prediluted pH value ranges from approximately 10 to 11.
Claim 14
Dependent Claim 21 words
The method as recited in claim 1, wherein said adjusting comprises adding potassium hydroxide or ammonium hydroxide to the diluted slurry.
Claim 15
Dependent Claim 29 words
The method as recited in claim 1, wherein said adjusting comprises adding a 0.5 to 2% by weight solution of potassium hydroxide or ammonium hydroxide to the diluted slurry.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-09-27 2003-03-29 2003-09-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-09-27 2007-03-29 2007-09-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-09-27 2011-03-29 2011-09-28 $7700.00 Window Closed / Lapsed

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