← Back to Patent Explorer
US5183402A Expired / Lapsed US ⏱️ 0.0 years remaining

Workpiece support

Assignee: Electrotech Ltd
•
Filing: 1991-05-14
•
Granted: 1993-02-02
•
Expires: 2011-05-14
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An apparatus for supporting a workpiece has an enclosure, a means for reducing the pressure and a platen on which the workpiece is mounted. A heating mechanism is located within the platen and the platen is coated with a high emissivity material, which facilitates the radiative heat transfer between the platen and the workpiece. Consequently, the workpiece can be rapidly raised to a specific temperature. This apparatus is particularly applicable to the supporting of a semiconductor wafer within a vacuum system.

Inventors

  • 👤 Michael J. Cooke
  • 👤 Arthur J. McGeown

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 10:52
CPC Classifications
F; F27; F27D; F27D5/00; F27D3/00; F27D2003/0034; F27D2003/0068; F27D7/00; F27D7/06; F27D2007/066; F27D99/00; F27D99/0001; F27D2099/0061

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 95 words
An apparatus for supporting a workpiece comprising: an enclosure; means for reducing the pressure within the enclosure; a platen in the enclose for supporting a workpiece on a surface thereof, said surface of the platen having a coating for assisting heat transfer between the workpiece supported on the platen and the platen, said coating having an emissivity not less than the emissivity of the workpiece; and means for heating the workpiece supported on the platen to a temperature of at least 200° C., said workpiece having an emissivity not greater than that of said coating.
Claim 2
Independent Claim 95 words
An apparatus for supporting a workpiece comprising: an enclosure; means for reducing the pressure within the enclosure; a platen in the enclose for supporting a workpiece on a surface thereof, said surface of the platen having a coating for assisting heat transfer between the workpiece supported on the platen and the platen, said coating having an emissivity not less than the emissivity of the workpiece; and means for heating the workpiece supported on the platen to a temperature of at least 200° C., said workpiece having an emissivity not greater than that of said coating.
Claim 3
Dependent Claim 17 words
An apparatus according to claim 1, wherein the coating has a thickness not less than 25 μm.
Claim 4
Dependent Claim 17 words
An apparatus according to claim 1, wherein the coating has a thickness not greater than 50 μm.
Claim 5
Dependent Claim 13 words
An apparatus according to claim 1, wherein the coating has a roughened surface.
Claim 6
Dependent Claim 14 words
An apparatus according to claim 1, wherein the coating is formed by plasma spraying.
Claim 7
Dependent Claim 17 words
An apparatus according to claim 1, wherein the means for heating the workpiece is within said platen.
Claim 8
Dependent Claim 21 words
An apparatus according to claim 1, wherein the apparatus includes means for introducing a gas between the platen and the workpiece.
Claim 9
Dependent Claim 13 words
An apparatus according to claim 7 wherein the gas comprises a polyatomic gas.
Claim 10
Dependent Claim 89 words
An apparatus according to claim 1, wherein the platen is movable within the enclosure between an operative position and a withdrawn position, and wherein there are a plurality of pins in the enclosure adjacent the platen, the pins extending in a first direction such that, when the platen is in its operative position, the ends of the pins do not project beyond the surface of the platen for supporting the workpiece, and when the platen is in its withdrawn position, the ends of the pins project beyond the surface.
Claim 11
Dependent Claim 14 words
An apparatus according to claim 1, wherein said coating is a refractory metal oxide.
Claim 12
Dependent Claim 17 words
An apparatus as recited in claim 1 wherein said coating has an emissivity of at least 0.7.
Claim 13
Independent Claim 74 words
A method of treating a workpiece, comprising the steps of: mounting said workpiece on a surface of a supporting platen, said supporting platen being within an enclosure, said surface having a coating thereon for assisting heat transfer between the workpiece and the platen, which coating has an emissivity not less than the emissivity of the workpiece; reducing the pressure within the enclosure; and heating the workpiece to a temperature of at least 200° C.
Claim 14
Independent Claim 74 words
A method of treating a workpiece, comprising the steps of: mounting said workpiece on a surface of a supporting platen, said supporting platen being within an enclosure, said surface having a coating thereon for assisting heat transfer between the workpiece and the platen, which coating has an emissivity not less than the emissivity of the workpiece; reducing the pressure within the enclosure; and heating the workpiece to a temperature of at least 200° C.
Claim 15
Dependent Claim 21 words
A method as recited in claim 12 further comprising the step of introducing a gas between the platen and the workpiece.
Claim 16
Dependent Claim 23 words
A method as recited in claim 13 wherein said gas comprises a poly atomic gas at a pressure of 0.5 to 8 Torr.
Claim 17
Dependent Claim 24 words
A method as recited in claim 12 further comprising the step of depositing a film on said workpiece by physical or chemical vapour deposition.

References Cited (Backward Citations)

US2798716A Cited
US3951587A Cited
EP0015234A1 Cited
EP0016579A1 Cited
US4259061A Cited
US4610628A Cited
US4613305A Cited
EP0250064A2 Cited
EP0290218A2 Cited
EP0326838A1 Cited
US5044943A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-02-02 1996-08-03 1997-02-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-02-02 2000-08-03 2001-02-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-02-02 2004-08-03 2005-02-02 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag