Flip chip heat sink package and method

• US 7,180,745 B2
• Filed: 10/10/2003
• Issued: 02/20/2007
• Est. Priority Date: 10/10/2003
• Status: Active Grant

• Current Assignee: Delphi Technologies Ip Limited (BorgWarner Incorporated)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Zimmerman, David W., Sarma, Dwadasi H., Chengalva, Suresh K., Gertiser, Kevin M., Mandel, Larry M
• Primary Examiner(s): Datskovskiy, Michael
• Application Number:
  US10/683,015
• Publication Number:
  US 20050078456A1
• Time in Patent Office: 1,229 Days
• Field of Search: 257/706, 257/713, 361/704, 361/707, 361/719
• US Class Current: 361/719
• CPC Class Codes: H01L 21/4878 Mechanical treatment, e.g. deforming
• CPC Class Codes: H01L 21/4882 Assembly of heatsink parts
• CPC Class Codes: H01L 21/563 Encapsulation of active face of flip-chip device, e.g. underfilling or underencapsulation of flip-chip, encapsulation preform on chip or mounting substrate
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2224/73204 the bump connector being embedded into the layer connector
• CPC Class Codes: H01L 2224/73253 Bump and layer connectors
• CPC Class Codes: H01L 23/3675 characterised by the shape of the housing
• CPC Class Codes: H01L 23/3677 Wire-like or pin-like cooling fins or heat sinks
• CPC Class Codes: H01L 23/42 Fillings or auxiliary members in containers or encapsulations selected or arranged to facilitate heating or cooling
• CPC Class Codes: H01L 23/427 Cooling by change of state, e.g. use of heat pipes by liquefied gas H01L23/445
• CPC Class Codes: Y10T 29/49144 by metal fusion

Abstract

An electronic package having enhanced heat dissipation is provided exhibiting dual conductive heat paths in opposing directions. The package includes a substrate having electrical conductors thereon and a flip chip mounted to the substrate. The flip chip has a first surface, solder bumps on the first surface, and a second surface oppositely disposed from the first surface. The flip chip is mounted to the substrate such that the solder bumps are registered with the conductors on the substrate. The package further includes a stamped metal heat sink in heat transfer relationship with the second surface of the flip chip. The heat sink includes a cavity formed adjacent to the flip chip containing a thermally conductive material.

Claims

1. An electronic package comprising:

a substrate having electrical conductors thereon;

a flip chip mounted to the substrate, the flip chip having a first surface, solder bumps on the first surface, and a second surface oppositely disposed from the first surface, the flip chip being mounted to the substrate such that the solder bumps are registered with the conductors on the substrate;

a heat sink in heat transfer relationship with the second surface of the flip chip, wherein the heat sink includes a cavity formed in a region adjacent to the flip chip; and

a case in heat transfer relationship with the substrate, with the heat sink comprising a cover.

2. The package as defined in claim 1 further comprising a thermally conductive material disposed within the cavity of the heat sink.

3. The package as defined in claim 2, wherein the thermally conductive material comprises a metal insert.

4. The package as defined in claim 2, wherein the thermally conductive material comprises solder.

5. The package as defined in claim 2, wherein the thermally conductive material comprises a phase change material.

6. The package as defined in claim 1, wherein the heat sink provides a first heat conduction path and the case provides a second heat conduction path for dissipating heat energy away from the flip chip.

7. The package as defined in claim 6 further comprising a plurality of conductive vias formed within the substrate for conducting heat from the first surface of the flip chip through the substrate to the thermally conductive member.

8. The package as defined in claim 1, wherein the heat sink comprises a stamped metal heat sink.

9. The package as defined in claim 1 further comprising a plurality of cooling fins.

10. The package as defined in claim 1 further comprising a thermally conductive interface material disposed between the second surface of the flip chip and the heat sink.