US4457359A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for gas-assisted, solid-to-solid thermal transfer with a semiconductor wafer
Assignee: Varian Semiconductor Equipment Associates Inc
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Filing: 1982-05-25
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Granted: 1984-07-03
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Expires: 2002-05-25
Abstract
Abstract Apparatus and method are provided for effecting gas-assisted, solid-to-solid thermal transfer with a semiconductor wafer. A semiconductor wafer is loaded at its periphery onto a shaped platen. Sufficient contact pressure from the loading is produced between the wafer and the platen so that significant gas pressure may be accommodated against the back side of the wafer without having the wafer bow outwardly or break. Gas under pressure is introduced into the microscopic void region between the platen and the wafer. The gas fills the microscopic voids between the platen and semiconductor wafer. The gas pressure approaches that of the preloading contact pressure without any appreciable increase in the wafer-to-platen spacing. Since the gas pressure is significantly increased without any increase in the wafer-to-platen gap, the thermal resistance is reduced and solid-to-solid thermal transfer with gas assistance produces optimum results.
Inventors
- 👤 Scott C. Holden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:35
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0431; H10P72/0432; H10P72/70; H10P72/76; H10P72/7604; H10P72/7606; H10P72/7611; H10P72/78
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
103 words
Apparatus for effecting thermal transfer with a thin flexible disk in vacuum, comprising: a platen having a nonplanar surface for receiving said disk and forming a solid-to-solid contact with the back side of said disk; means for clamping said disk at its periphery against said platen surface to produce a platen-to-disk preloading contact pressure; and means for introducing a gas into microscopic voids between said disk and said platen surface at a predetermined pressure above the level sufficient to cause bowing and reduced thermal transfer with a disk which is not preloaded, said predetermined gas pressure being less than said preloading contact pressure.
Claim 2
Dependent Claim
103 words
Apparatus for effecting thermal transfer with a thin flexible disk in vacuum, comprising: a platen having a nonplanar surface for receiving said disk and forming a solid-to-solid contact with the back side of said disk; means for clamping said disk at its periphery against said platen surface to produce a platen-to-disk preloading contact pressure; and means for introducing a gas into microscopic voids between said disk and said platen surface at a predetermined pressure above the level sufficient to cause bowing and reduced thermal transfer with a disk which is not preloaded, said predetermined gas pressure being less than said preloading contact pressure.
Claim 3
Dependent Claim
13 words
Apparatus as defined in claim 1 wherein said platen surface is convexly curved.
Claim 4
Dependent Claim
44 words
Apparatus as defined in claim 2 wherein said means for introducing a gas comprises an open circular channel in said platen surface having a radius less than said disk and a conduit in said platen for coupling said circular channel to a gas source.
Claim 5
Dependent Claim
26 words
Apparatus as defined in claim 3 further including sealing means in said platen surface radially outward from said circular channel for preventing escape of said gas.
Claim 6
Dependent Claim
18 words
Apparatus as defined in claim 4 wherein said platen includes channels for circulation of a heat transfer fluid.
Claim 7
Dependent Claim
24 words
Apparatus as defined in claim 1 wherein said platen surface has a contour which produces uniform preloading over the surface area of said disk.
Claim 8
Dependent Claim
13 words
Apparatus as defined in claim 6 wherein said disk comprises a semiconductor wafer.
Claim 9
Dependent Claim
45 words
Apparatus as defined in claim 7 wherein said means for clamping said wafer applies a preloading force to permit said wafer to accommodate gas pressure across its back side in the range of 5 Torr to 100 Torr without lifting or bowing to the wafer.
Claim 10
Dependent Claim
134 words
Apparatus for effecting thermal transfer with a semiconductor wafer in a vacuum processing chamber, comprising: a platen having a nonplanar surface for receiving said wafer and forming a solid-to-solid contact with the back side of said wafer; means for loading said wafer at its periphery against said platen surface so as to produce a platen-to-wafer preloading contact pressure over the surface area of said wafer sufficient to maintain solid-to-solid contact between said wafer and said platen when gas is introduced into the microscopic voids between the platen and the wafer; and means for introducing a gas into said microscopic voids between said platen and said wafer at a pressure less than said preloading contact pressure but above the pressure sufficient to cause bowing and reduced thermal transfer with a wafer which is not preloaded.
Claim 11
Dependent Claim
134 words
Apparatus for effecting thermal transfer with a semiconductor wafer in a vacuum processing chamber, comprising: a platen having a nonplanar surface for receiving said wafer and forming a solid-to-solid contact with the back side of said wafer; means for loading said wafer at its periphery against said platen surface so as to produce a platen-to-wafer preloading contact pressure over the surface area of said wafer sufficient to maintain solid-to-solid contact between said wafer and said platen when gas is introduced into the microscopic voids between the platen and the wafer; and means for introducing a gas into said microscopic voids between said platen and said wafer at a pressure less than said preloading contact pressure but above the pressure sufficient to cause bowing and reduced thermal transfer with a wafer which is not preloaded.
Claim 12
Dependent Claim
18 words
Apparatus for effecting thermal transfer in accordance with claim 9 wherein said platen has a convexly curved surface.
Claim 13
Dependent Claim
26 words
Apparatus for effecting thermal transfer in accordance with claim 10 wherein said convexly curved platen surface has a finished metallic surface for receiving said semiconductor wafer.
Claim 14
Dependent Claim
22 words
Apparatus for effecting thermal transfer in accordance with claim 11 wherein said finished metallic surface is a finished metallic surface of aluminum.
Claim 15
Dependent Claim
29 words
Apparatus for effecting thermal transfer in accordance with claim 10 wherein said convexly curved platen has a resilient, thermally conductive polymer surface affixed thereto for receiving said semiconductor wafer.
Claim 16
Dependent Claim
60 words
Apparatus for effecting thermal transfer in accordance with claim 9 wherein said means for introducing a gas comprises a channel within said platen which is connected externally to a gas source and terminates in an open circular channel in the surface of said platen having a radius slightly less than that of said wafer which is loaded onto said platen.
Claim 17
Dependent Claim
36 words
Apparatus for effecting thermal transfer in accordance with claim 14 in combination with sealing means embedded in the surface of said platen external to said open circular channel to prevent gas from entering the processing chamber.
Claim 18
Dependent Claim
26 words
Apparatus for effecting thermal transfer in accordance with claim 15 wherein said platen further includes a second network of channels for circulating a heat transfer fluid.
Claim 19
Dependent Claim
153 words
Apparatus for effecting thermal transfer with a semiconductor wafer in a vacuum processing chamber, comprising: a platen having a nonplanar surface for receiving said wafer and forming a solid-to-solid contact with the back side of said wafer; means for loading said wafer at its periphery against said platen surface so as to produce a platen-to-wafer preloading contact pressure over the surface area of said wafer sufficient to maintain solid-to-solid contact between said wafer and said platen when gas is introduced into the microscopic voids between the platen and the wafer; and means for introducing a gas into said microscopic voids between said platen and said wafer at a pressure less than said preloading contact pressure, said means for loading said wafer applying a preloading force to permit said wafer to accommodate gas pressure across its back side in the range of 5 Torr to 100 Torr without lifting or bowing of the wafer.
Claim 20
Dependent Claim
153 words
Apparatus for effecting thermal transfer with a semiconductor wafer in a vacuum processing chamber, comprising: a platen having a nonplanar surface for receiving said wafer and forming a solid-to-solid contact with the back side of said wafer; means for loading said wafer at its periphery against said platen surface so as to produce a platen-to-wafer preloading contact pressure over the surface area of said wafer sufficient to maintain solid-to-solid contact between said wafer and said platen when gas is introduced into the microscopic voids between the platen and the wafer; and means for introducing a gas into said microscopic voids between said platen and said wafer at a pressure less than said preloading contact pressure, said means for loading said wafer applying a preloading force to permit said wafer to accommodate gas pressure across its back side in the range of 5 Torr to 100 Torr without lifting or bowing of the wafer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-03 | 1988-01-02 | 1988-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-03 | 1992-01-02 | 1992-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-03 | 1996-01-02 | 1996-07-03 | $7700.00 | Window Closed / Lapsed |