Multi-chip package having a contiguous heat spreader assembly

• US 6,963,129 B1
• Filed: 06/18/2003
• Issued: 11/08/2005
• Est. Priority Date: 06/18/2003
• Status: Expired due to Term

• Current Assignee: Bell Northern Research, LLC (Hilco Inc. (d/b/a Hilco Global))
• Original Assignee: LSI Logic Corporation (Broadcom, Inc.)
• Inventors: Evans, Thomas, Miller, Leah M., Nagarajan, Kumar, Mihelcic, Stan, Fulcher, Edwin M.
• Primary Examiner(s): Cao, Phat X.
• Application Number:
  US10/464,178
• Time in Patent Office: 874 Days
• Field of Search: 257/723, 257/706, 257/707
• US Class Current: 257/706
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/73253 Bump and layer connectors
• CPC Class Codes: H01L 23/36 Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks H01L23/28, H01L23/40, H01L23/42, H01L23/44, H01L23/46 take precedence; heating H01L23/345
• CPC Class Codes: H01L 25/0655 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/15153 the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/1517 Multilayer substrate
• CPC Class Codes: H01L 2924/15311 being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/16195 Flat cap [not enclosing an internal cavity]
• CPC Class Codes: H01L 2924/19105 in a side-by-side arrangement on a common die mounting substrate

Abstract

A system and method are provided for forming a multi-chip package. The multi-chip package includes a multi-layer substrate and a heat spreader of single, unibody construction. At least two integrated circuits are coupled between the multi-layer substrate and the heat spreader. The integrated circuits are spaced from one another to allow airflow between those circuits and a portion of the underside surface of the heat spreader. Depending on the layout of the package, a passive device can also be placed in the space between integrated circuits. The passive device extends upward a spaced distance from the underneath surface of the heat spreader so as not to block the airflow therebetween. The multi-chip package can accommodate integrated circuits that are either all packaged, all unpackaged, or a combination of each. If packaged and unpackaged integrated circuits are placed on the multi-layer substrate, the heat spreader can extend in two separate planes to accommodate the different thicknesses of those packaged and unpackaged integrated circuits. Alternatively, a second heat spreader can be placed on a relatively thin integrated circuit so that the upper surface of the second heat spreader is coplanar with an upper surface of a relatively thick integrated circuit. This will allow a planar heat spreader to be arranged across the thick integrated circuit and the second heat spreader. In all instances, however, the heat spreader extends as a single, contiguous unibody element across the entire multi-chip package.

Claims

1. A heat spreader assembly, comprising:

a single, unibody heat spreader configured to extend across substantially the entire first surface of at least two spaced integrated circuits opposite a second surface of the integrated circuits having a bonding pad;

adhesive placed between the heat spreader and the first surface for securing the heat spreader to the first surface of the integrated circuits at a spaced distance above at least one passive device arranged in the area between the spaced integrated circuits; and

a second heat spreader interposed between the heat spreader and only of the at least two spaced integrated circuits.

2. The heat spreader assembly as recited in claim 1, wherein the heat spreader extends along a single plane.

3. The heat spreader assembly as recited in claim 1, wherein the beat spreader extends along two planes.

4. The heat spreader assembly as recited in claim 1, wherein an upper surface of the second heat spreader is coplanar with an upper surface of only one of the at least two spaced integrated circuits.

5. The heat spreader assembly as recited in claim 1, wherein the heat spreader is thermally conductive.

6. The heat spreader assembly as recited in claim 1, wherein the heat spreader comprises copper or other metal material.