Structure and process for electrical interconnect and thermal management

• US 8,035,223 B2
• Filed: 08/28/2007
• Issued: 10/11/2011
• Est. Priority Date: 08/28/2007
• Status: Active Grant

• Current Assignee: Micross Advanced Interconnect Technology LLC
• Original Assignee: Research Triangle Institute
• Inventors: Williams, Charles Kenneth, Garrou, Philip, Bower, Christopher A.
• Primary Examiner(s): Tran; Minh-Loan T
• Assistant Examiner(s): Cruz; Leslie Pilar
• Application Number:
  US11/846,253
• Publication Number:
  US 20090057879A1
• Time in Patent Office: 1,505 Days
• Field of Search: 257/276, 257/625, 257/686, 257/712, 257/713, 257/714, 257/716, 257/717, 257/777, 257/E23.097, 257/E23.098, 257/E23.099, 257/E23.102
• US Class Current: 257/713
• CPC Class Codes: H01L 2224/02372 connecting to a via connection in the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/05 of an individual bonding area
• CPC Class Codes: H01L 2224/05548 Bonding area integrally formed with a redistribution layer on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/13 of an individual bump connector
• CPC Class Codes: H01L 2224/13024 the bump connector being disposed on a redistribution layer on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/13025 the bump connector being disposed on a via connection of the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/131 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/14181 On opposite sides of the body
• CPC Class Codes: H01L 2224/16145 the bodies being stacked
• CPC Class Codes: H01L 2224/16146 the bump connector connecting to a via connection in the semiconductor or solid-state body
• CPC Class Codes: H01L 2225/06513 Bump or bump-like direct electrical connections between devices, e.g. flip-chip connection, solder bumps
• CPC Class Codes: H01L 2225/06589 Thermal management, e.g. cooling
• CPC Class Codes: H01L 23/473 by flowing liquids H01L23/4332, H01L23/4338 take precedence
• CPC Class Codes: H01L 23/481 Internal lead connections, e.g. via connections, feedthrough structures
• CPC Class Codes: H01L 25/0657 Stacked arrangements of devices
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/014 Solder alloys
• CPC Class Codes: H01L 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]

Abstract

A structure and method for thermal management of integrated circuits. The structure for thermal management of integrated circuits includes first and second substrates bonded together, at least one of the first and second substrates including at least one circuit element, an entrance through-hole having a length extending through a thickness of at least one of the first substrate and the second substrate, an exit through-hole having a length extending through a thickness of at least one of the first substrate and the second substrate, a bonding element forming a seal between the first and second substrates and forming a space between the first and second substrate, and a coolant channel formed in the space between the first and second substrates such that a fluid entering the entrance through-hole transits the coolant channel and the exit through-hole to provide cooling to the circuit element. The method supplies a fluid through the entrance through-hole, flows the fluid through the coolant channel between the first substrate and second substrates, and removes the fluid from the coolant channel through the exit through-hole.

Claims

1. A structure for thermal management, comprising:

first and second substrates bonded together;

at least one of the first and second substrates including at least one circuit element;

an entrance through-hole having a length extending through a thickness of at least one of the first and second substrates;

an exit through-hole having a length extending through a thickness of at least one of the first and second substrates;

a first coolant channel formed in a space between the first and second substrates such that a fluid entering the entrance through-hole transits the first coolant channel and the exit through-hole to provide cooling to the circuit element;

a bonding element forming a seal between the first and second substrates and having a thickness extending from a surface of at least one of the first and second substrates, and

a space for the first coolant channel extending between the first and second substrates and separating the first and second substrates defined principally by said thickness of the bonding element.

2. The structure of claim 1, further comprising:

a metallic interconnect extending across the thickness of the first substrate or the second substrate and comprising an electrical connection to the circuit element.

3. The structure of claim 1, wherein the at least one circuit element comprises heat-generating circuits.

4. The structure of claim 1, wherein the bonding element comprises:

a eutectic alloy joining the first and second substrate.

5. The method of claim 4, wherein the eutectic alloy comprises:

an alloy including at least one of Cu, Sn, Au, and Pb.

6. The structure of claim 1, wherein the first coolant channel comprises an undulating path for fluid flow between the first and second substrates.

7. The structure of claim 6, wherein the undulating path comprises at least one of a serpentine path and a spiral path.

8. The structure of claim 1, further comprising a third substrate, and

wherein at least one the first, second, and third substrates includes heat-generating circuits.

9. The structure of claim 8, further comprising:

a second coolant channel formed in a space between the second and third substrates such that the second coolant channel provides cooling to the second and third substrates.

10. The structure of claim 1, wherein at least one of the entrance through-hole and the exit through-hole comprises:

two passages through the first substrate or through the second substrate, said passages connecting to the first coolant channel.

11. The structure of claim 10, wherein at least one of the two passages has an interior insulator disposed on interior surfaces of the passages.

12. The structure of claim 11, wherein the interior insulator comprises:

an air region, an inert gas region, a SiO₂ layer, a Si₃N₄ layer, a SiO_xN_y, a non-porous insulating layer, a polymeric layer, or any combination thereof.

13. The structure of claim 1, wherein at least one of the entrance through-hole and the exit through-hole comprises:

a metallic conduit extending across the thickness of the first substrate or the second substrate.

14. The structure of claim 13, wherein the metallic conduit comprises a metallic interconnect extending across the thickness of the first substrate or the second substrate and comprising an electrical connection to the circuit element.

15. The structure of claim 13, further comprising:

an electrical isolation region surrounding the metallic conduit.

16. The structure of claim 15, wherein the electrical isolation region comprises:

an air region, an inert gas region, a SiO₂ layer, a Si₃N₄ layer, a SiO_xN_y layer, a non-porous insulating layer, a polymeric layer, or any combination thereof.

17. The structure of claim 13, wherein the metal conduit comprises a flange.

18. The structure of claim 17, further comprising:

a metallic interconnect extending through the thickness of the first substrate or the second substrate and connected to the flange.

19. The structure of claim 18, further comprising:

an electrical insulator isolating the metallic interconnect from an interior of the entrance through-hole or the exit through-hole.

20. The structure of claim 19, wherein the electrical insulator comprises:

an air region, an inert gas region, a SiO₂ layer, a Si₃N₄ layer, a SiO_xN_y layer, a non-porous insulating layer, a polymeric layer, or any combination thereof.

21. A structure for thermal management, comprising:

first and second substrates bonded together;

at least one of the first and second substrates including at least one circuit element;

an entrance through-hole having a length extending through a thickness of at least one of the first and second substrates;

an exit through-hole having a length extending through a thickness of at least one of the first and second substrates;

a first coolant channel provided between the first and second substrates such that a fluid entering the entrance through-hole transits the first coolant channel and the exit through-hole to provide cooling to the circuit element;

a bonding element forming a seal between the first and second substrates;

said first cooling channel having,

side surfaces completely bounded by the bonding element,

and top and bottom surfaces completely bounded by the opposed first and second substrates.

22. The structure of claim 21, further comprising:

a metallic interconnect extending across the thickness of the first substrate or the second substrate and comprising an electrical connection to the circuit element.

23. The structure of claim 21, wherein the at least one circuit element comprises heat-generating circuits.

24. The structure of claim 21, wherein the bonding element comprises:

a eutectic alloy joining the first and second substrate.

25. The method of claim 24, wherein the eutectic alloy comprises:

an alloy including at least one of Cu, Sn, Au, and Pb.

26. The structure of claim 21, wherein the first coolant channel comprises an undulating path for fluid flow between the first and second substrates.

27. The structure of claim 26, wherein the undulating path comprises at least one of a serpentine path and a spiral path.

28. The structure of claim 21, further comprising a third substrate, and

wherein at least one the first, second, and third substrates includes heat-generating circuits.

29. The structure of claim 28, further comprising:

a second coolant channel formed in a space between the second and third substrates such that the second coolant channel provides cooling to the second and third substrates.

30. The structure of claim 21, wherein at least one of the entrance through-hole and the exit through-hole comprises:

two passages through the first substrate or through the second substrate, said passages connecting to the first coolant channel.

31. The structure of claim 30, wherein at least one of the two passages has an interior insulator disposed on interior surfaces of the passages.

32. The structure of claim 31, wherein the interior insulator comprises:

an air region, an inert gas region, a SiO₂ layer, a Si₃N₄ layer, a SiO_xN_y, a non-porous insulating layer, a polymeric layer, or any combination thereof.

33. The structure of claim 21, wherein at least one of the entrance through-hole and the exit through-hole comprises:

a metallic conduit extending across the thickness of the first substrate or the second substrate.

34. The structure of claim 33, wherein the metallic conduit comprises a metallic interconnect extending across the thickness of the first substrate or the second substrate and comprising an electrical connection to the circuit element.

35. The structure of claim 33, further comprising:

an electrical isolation region surrounding the metallic conduit.

36. The structure of claim 35, wherein the electrical isolation region comprises:

an air region, an inert gas region, a SiO₂ layer, a Si₃N₄ layer, a SiO_xN_y layer, a non-porous insulating layer, a polymeric layer, or any combination thereof.

37. The structure of claim 33, wherein the metal conduit comprises a flange.

38. The structure of claim 37, further comprising:

a metallic interconnect extending through the thickness of the first substrate or the second substrate and connected to the flange.

39. The structure of claim 38, further comprising:

an electrical insulator isolating the metallic interconnect from an interior of the entrance through-hole or the exit through-hole.

40. The structure of claim 39, wherein the electrical insulator comprises:

an air region, an inert gas region, a SiO₂ layer, a Si₃N₄ layer, a SiO_xN_y layer, a non-porous insulating layer, a polymeric layer, or any combination thereof.