Device and method for convective cooling of an electronic component

• US 5,784,255 A
• Filed: 12/04/1995
• Issued: 07/21/1998
• Est. Priority Date: 12/04/1995
• Status: Expired due to Term

• Current Assignee: Integrated Device Technology Incorporated (Renesas Electronics Corporation)
• Original Assignee: Integrated Device Technology Incorporated (Renesas Electronics Corporation)
• Inventors: Wyland, Christopher P.
• Primary Examiner(s): Tolin, Gerald P.
• Application Number:
  US08/566,757
• Time in Patent Office: 960 Days
• Field of Search: 174/16.1, 174/16.3, 174/15.1, 165/80.3, 165/185, 165/122, 165/126, 165/108, 165/129, 165/128, 165/900, 165/131, 257/706, 257/707, 257/713, 257/720-722, 361/690, 361/692, 361/693, 361/704, 361/705, 361/706, 361/709-711, 361/717-720
• US Class Current: 361/692
• CPC Class Codes: H01L 23/367 Cooling facilitated by shape of device H01L23/38, H01L23/40, H01L23/42, H01L23/44, H01L23/46 take precedence
• CPC Class Codes: H01L 23/3677 Wire-like or pin-like cooling fins or heat sinks
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A heat sink mounted on an electronic component causes a thermal plume effect so that air adjacent to the electronic component moves through one or more channels in the heat sink in a direction substantially transverse to and away from the electronic component. The heat sink includes a base attachable to the electronic component, a support member mounted on and substantially transverse to the base, and a heat exchanger mounted on the support member and spaced away from the base. The heat exchanger has at least one entry hole adjacent to the base, at least one exit hole at a distance from the entry hole, and one or more channels adjacent to the support member and in flow communication with the entry hole and the exit hole.

Claims

1. A heat sink for cooling an electronic component, said heat sink comprising:

a base;

a support member connected to said base; and

a heat exchanger supported substantially on said support member and surrounding at least a substantial portion of said support member, wherein;

said heat exchanger defines at least one entry hole adjacent said base and at least one exit hole at a distance from said entry hole, said exit hole being in flow communication with ambient air adjacent to said heat sink, said distance being sufficient for a thermal gradient in said heat exchanger between said entry hole and said exit hole to cause movement of ambient air from said entry hole to said exit hole by natural convection;

said heat exchanger defines at least one channel adjacent said support member and in flow communication with said entry hole and said exit hole;

said heat exchanger comprises a tube and at least one radial member extending radially from said support member to said tube, said tube surrounding said support member and located approximately concentric with said support member; and

said heat exchanger is devoid of a fan for moving said air.

2. The heat sink of claim 1 wherein said support member, said tube and said radial member are portions of an integral structure.

3. The heat sink of claim 1 wherein said tube is cylindrical.

4. The heat sink of claim 1 wherein said tube defines a plurality of entry holes including said entry hole, each entry hole being in flow communication with a region outside said tube and adjacent to said base.

5. The heat sink of claim 1 wherein said radial member comprises a wall.

6. The heat sink of claim 5 wherein said radial wall defines a plurality of internal holes.

7. The heat sink of claim 1 wherein said radial member comprises a spoke.

8. A heat sink for cooling an electronic component, said heat sink comprising:

a base;

a support member connected to said base; and

a heat exchanger supported substantially on said support member and surrounding at least a substantial portion of said support member, wherein;

said heat exchanger defines at least one entry hole adjacent said base and at least one exit hole at a distance from said entry hole, said exit hole being in flow communication with ambient air adjacent to said heat sink, said distance being sufficient for a thermal gradient in said heat exchanger between said entry hole and said exit hole to cause movement of ambient air from said entry hole to said exit hole by natural convection;

said heat exchanger defines at least one channel adjacent said support member and in flow communication with said entry hole and said exit hole; and

said heat exchanger comprises a cylindrical wall and a plurality of radial walls, each radial wall extending radially from said support member to said cylindrical wall.

9. The heat sink of claim 8 wherein said cylindrical wall defines a plurality of entry holes including said entry hole.

10. The heat sink of claim 8 wherein said support member, said cylindrical wall and said radial wall are portions of an integral structure.

11. A heat sink for cooling an electronic component, said heat sink comprising:

a base;

a support member connected to said base; and

a heat exchanger supported substantially on said support member and surrounding at least a substantial portion of said support member, wherein;

said heat exchanger defines at least one entry hole adjacent said base and at least one exit hole at a distance from said entry hole, said exit hole being in flow communication with ambient air adjacent to said heat sink, said distance being sufficient for a thermal gradient in said heat exchanger between said entry hole and said exit hole to cause movement of ambient air from said entry hole to said exit hole by natural convection;

said heat exchanger defines at least one channel adjacent said support member and in flow communication with said entry hole and said exit hole; and

said heat exchanger comprises a sponge.

12. An assembly comprising an electronic module and a heat sink mounted on said electronic module, said heat sink comprising:

a base attached to said electronic module;

a support member connected to said base; and

a heat exchanger having a length smaller than the length of said support member and supported on said support member, said heat exchanger defining at least one entry hole facing said base, said heat exchanger further defining at least one exit hole and a channel adjacent said support member in flow communication with said entry hole and said exit hole.

13. The assembly of claim 12 wherein said base is mounted in intimate thermal contact with a portion of said electronic component to minimize the junction to case resistance.

14. The assembly of claim 13 wherein said base of said heat sink is embedded in said electronic component and wherein said portion of said electronic component is a copper slug.

15. A method for cooling an electronic component comprising:

generating heat in said electronic component, said heat passes from said electronic component into a support member mounted transverse to said electronic component;

using a heat exchanger supported by said support member such that said heat from said electronic component generates a thermal gradient in said heat exchanger between an entry hole and an exit hole of said heat exchanger thereby causing said ambient air to move from said entry hole to said exit hole by natural convection due to said thermal gradient, wherein;

ambient air enters said entry hole, and flows through at least one channel of said heat due to said thermal gradient;

air in said channel leaves said heat exchanger through said exit hole; and

air in said heat exchanger absorbs heat from a plurality of radial members connected to said support member.

16. The method of claim 15 wherein air in said heat exchanger travels adjacent to said support member without being moved by a fan.

17. The method of claim 15 wherein said entry hole faces said electronic component and air adjacent said electronic component enters said heat exchanger through said entry hole.

18. The method of claim 15 wherein ambient air further enters said heat exchanger through an external hole transverse to said electronic component.