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US4381818A Expired / Lapsed US ⏱️ 0.0 years remaining

Porous film heat transfer

Assignee: International Business Machines Corp
•
Filing: 1980-03-26
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Granted: 1983-05-03
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Expires: 2000-03-26
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Abstract

Abstract A silicon substrate adapted for large scale integrated electronic circuits upon a lower surface has its upper surface coated with a highly porous heat sink film. The film is composed of a porous metal, preferably aluminum, formed by vacuum deposition (evaporation or sputtering) at a high pressure of an inactive gas. The gas can have a pressure of from about 0.5-100 millitorr, and a suitable gas is argon. A porous aluminum film with interconnected nucleation sites which are in the form of reservoir type cavities is manufactured on a silicon surface. The cavities tend to trap vapor of a liquid coolant in contact with the thin film contained in a package enclosing the substrate and its integrated circuit. Cooling fins can be used to cool the coolant.

Inventors

  • 👤 Kenneth S. Sachar
  • 👤 Victor J. Silvestri

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 06:43
CPC Classifications
H; H10; H10W; H10W40/00; H10W40/70; H10W40/73; C; C23; C23C; C23C14/00; C23C14/06; C23C14/14; C23C14/16; C23C14/165; F; F28; F28F; F28F13/00; F28F13/18; F28F13/185; F28F13/187; Y; Y10; Y10S; Y10S165/00; Y10S165/907

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 156 words
A substrate for carrying a thin film electrical device upon a first surface thereof, comprising a silicon sheet with an electrical device upon said first surface, a sputtered, highly porous, vertically extending, columnar, thin film cooling structure deposited upon the opposite surface of said sheet of from about 9 micro-meters to about 15 micro-meters, said porous, columnar structure comprising an unoxidized, metallic, thin film, deposit with a plurality of substantially uniformly distributed, partially enclosed, vertically extending, vapor trapping, microscopic cavities having a diameter of about one to five micro-meters with convoluted, substantially vertically extending, nonconverging walls and openings at the upper surface on the order of one micro-meter in diameter and capillary structures with a substantial number of transverse interconnections between said cavities and adjacent ones of said cavities, and the thickness of said film being at least as great as the diameter of said cavities, thereby providing for substantial trapping of vapor in microscopic pores.
Claim 2
Dependent Claim 156 words
A substrate for carrying a thin film electrical device upon a first surface thereof, comprising a silicon sheet with an electrical device upon said first surface, a sputtered, highly porous, vertically extending, columnar, thin film cooling structure deposited upon the opposite surface of said sheet of from about 9 micro-meters to about 15 micro-meters, said porous, columnar structure comprising an unoxidized, metallic, thin film, deposit with a plurality of substantially uniformly distributed, partially enclosed, vertically extending, vapor trapping, microscopic cavities having a diameter of about one to five micro-meters with convoluted, substantially vertically extending, nonconverging walls and openings at the upper surface on the order of one micro-meter in diameter and capillary structures with a substantial number of transverse interconnections between said cavities and adjacent ones of said cavities, and the thickness of said film being at least as great as the diameter of said cavities, thereby providing for substantial trapping of vapor in microscopic pores.
Claim 3
Dependent Claim 168 words
A cooling system for a chip carrying an electrical device including a substrate comprising a silicon chip having a sputtered, metallic aluminum, vertically extending, columnar, highly porous structure upon a cooling surface thereof of from about 9 to about 15 micro-meters in thickness, a thin film electrical device upon the opposite surface thereof, a cooling liquid comprising a fluorocarbon, a chamber formed by said substrate and an enclosure holding said cooling fluid in contact with said porous structure, said highly porous structure comprising an unoxidized metallic aluminum, thin film deposit with a plurality of substantially uniformly distributed, partially enclosed, vertically extending, vapor trapping, microscopic cavities having a diameter of about five micro-meters with convoluted, substantially vertically extending, nonconverging walls and openings at the upper surface on the order of one micro-meter in diameter and transverse capillary structures interconnecting said cavities, and the thickness of said film structure is at least as great as the diameter of said cavities, thereby providing for substantial trapping of vapor in microscopic pores.
Claim 4
Dependent Claim 168 words
A cooling system for a chip carrying an electrical device including a substrate comprising a silicon chip having a sputtered, metallic aluminum, vertically extending, columnar, highly porous structure upon a cooling surface thereof of from about 9 to about 15 micro-meters in thickness, a thin film electrical device upon the opposite surface thereof, a cooling liquid comprising a fluorocarbon, a chamber formed by said substrate and an enclosure holding said cooling fluid in contact with said porous structure, said highly porous structure comprising an unoxidized metallic aluminum, thin film deposit with a plurality of substantially uniformly distributed, partially enclosed, vertically extending, vapor trapping, microscopic cavities having a diameter of about five micro-meters with convoluted, substantially vertically extending, nonconverging walls and openings at the upper surface on the order of one micro-meter in diameter and transverse capillary structures interconnecting said cavities, and the thickness of said film structure is at least as great as the diameter of said cavities, thereby providing for substantial trapping of vapor in microscopic pores.
Claim 5
Dependent Claim 39 words
A substrate in accordance with claim 1 or 2 wherein said film structure comprises a thin film of aluminum vacuum deposited at a relatively low temperature in a pressure of about 8 to 30 millitorr of an inert gas.

References Cited (Backward Citations)

GB804297A Cited
US3587730A Cited
US3622403A Cited
US3706127A Cited
US3598180A Cited
US3751295A Cited
US3739235A Cited
US4120994A Cited
US4064914A Cited
US3990862A Cited
US4258783A Cited
US4232056A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-05-02 1986-11-01 1987-05-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-05-02 1990-11-01 1991-05-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-05-02 1994-11-01 1995-05-03 $7700.00 Window Closed / Lapsed

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