Conformable heat sink interface with a high thermal conductivity

Patent metadata

Field	Value
Publication number	US-2020146183-A1
Application number	US-201816180499-A
Country	US
Kind code	A1
Filing date	Nov 5, 2018
Priority date	Nov 5, 2018
Publication date	May 7, 2020
Grant date	—

Abstract

A conformable heat sink interface for an integrated circuit package comprises a mounting plate having a first surface and a deformable membrane having a portion bonded to a second surface of the plate. A cavity is between the second surface of the plate and the deformable membrane. A flowable heat transfer medium is within the cavity. The flowable heat transfer medium has a thermal conductivity of not less than 30 W/m K. The deformable membrane is to conform to a three-dimensional shape of an IC package and the mounting plate has a second surface that is to be adjacent to a heat sink base.

First claim

We claim:

1 . A conformable heat sink interface for an integrated circuit package, comprising:
a mounting plate having a first surface; a deformable membrane having a portion thereof bonded to a second surface of the plate, wherein a cavity is between the second surface of the plate and the deformable membrane; and a flowable heat transfer medium within the cavity, wherein the flowable heat transfer medium has a thermal conductivity of not less than 30 W/m K, wherein the deformable membrane is to conform to a three-dimensional shape of a integrated circuit package and the mounting plate has a second surface that is to be adjacent to a heat sink base.

2 . The conformable heat sink interface of claim 1 , wherein the flowable heat transfer medium is a liquid metal having a liquidus temperature of not more than 30° C.

3 . The conformable heat sink interface of claim 2 , wherein the liquid metal comprises at least one of gallium, indium tin or zinc.

4 . The conformable heat sink interface of claim 1 , wherein at least one orifice extends through the plate over the cavity, and wherein the at least one orifice is surrounded by the deformable membrane.

5 . The conformable heat sink interface of claim 1 , wherein the deformable membrane has a thickness in the range of 10 and 50 microns.

6 . The conformable heat sink interface of claim 1 , wherein the deformable membrane comprises at least one of tungsten, tantalum, niobium, titanium, molybdenum, iron or nickel.

7 . The conformable heat sink interface of claim 1 , wherein the deformable membrane is bonded to the plate by at least one of a brazed joint, a weld joint, a solder joint, or an organic adhesive seal between the deformable membrane and the plate.

8 . The conformable heat sink interface of claim 1 , wherein the deformable membrane comprises a shape memory alloy comprising at least one of nickel, titanium, cobalt, copper, aluminum, zinc, iron, manganese or silicon.

9 . The conformable heat sink interface of claim 8 , wherein:
the deformable membrane comprises one or more mesas that protrude a distance over a surface of the deformable membrane; an integrated circuit package comprises at least one die attached to a substrate; the one or more mesas have lateral dimensions comprising a length and a width that are not less than the lateral dimensions of the at least one die; and the distance is complimentary to the z-height of the at least one die.

10 . The heat-exchange mount of claim 1 , wherein the thermal interface comprises a sealable opening in the deformable membrane, wherein the sealable opening comprises a fill hole.

11 . The conformable heat sink interface of claim 1 , wherein an overflow tube extends from an opening in the deformable membrane, and wherein the tube comprises at least one of a polymer or a metal.

12 . A integrated circuit package mounting assembly, comprising:
a integrated circuit package coupled to a printed circuit board; a power supply coupled to the integrated circuit package through the printed circuit board; a heat sink; a conformable heat sink interface between the integrated circuit package and the heat sink, the conformable heat sink interface comprising:
a mounting plate having a first surface adjacent to a base of the heat sink;
a deformable membrane having a portion thereof bonded to a second surface of the mounting plate, wherein a cavity is between the second surface of the plate and the deformable membrane; and
a flowable heat transfer medium within the cavity, wherein the flowable heat transfer medium has a thermal conductivity of not less than 30 W/m K,
wherein the deformable membrane is to conform to a three-dimensional shape of the integrated circuit package to enhance heat transfer between the integrated circuit package and the plate.

13 . The integrated circuit package mounting assembly of claim 12 , wherein the integrated circuit package comprises a microprocessor.

14 . The integrated circuit package mounting assembly of claim 12 , wherein the integrated circuit package comprises one or more dies attached to a substrate, wherein the deformable membrane comprises a shape memory alloy (SMA) and is embossed with one or more mesas, wherein the mesas are aligned to the one or more dies such that the one or more dies are abutted by the one or more mesas.

15 . The integrated circuit package mounting assembly of claim 12 , wherein a thermal interface material (TIM) layer is between the integrated circuit package and the deformable membrane.

16 . The integrated circuit package mounting assembly of claim 12 , wherein the cavity is coupled to pressure compensation tubing through orifices extending through the heat sink.

17 . A method for making a conformable thermal interface, comprising:
bonding a deformable membrane to a plate to form a seal around a cavity between the deformable membrane and the plate; and injecting a flowable thermal medium into the cavity, wherein the flowable heat transfer medium has a thermal conductivity of not less than 30 W/m K.

18 . The method for making a conformable thermal interface of claim 17 , wherein bonding the deformable membrane to the plate comprises at least one of braze welding the deformable membrane to the plate, soldering the deformable membrane to the plate or adhering the deformable membrane to the plate with an organic adhesive.

19 . The method for making the conformable thermal interface of claim 17 , wherein injecting the flowable thermal medium into the cavity comprises:
injecting the flowable thermal medium into the cavity through one or more orifices in the plate, wherein the one or more orifices extend though the plate and into the cavity, injecting the flowable thermal medium into the cavity through a sealable fill hole in the deformable membrane; or injecting the flowable thermal medium into the cavity through a tube extending into the cavity,
wherein the flowable thermal medium is a liquid metal or an organic liquid.

20 . The method for making the conformable thermal interface of claim 17 , wherein the deformable membrane comprises a shape memory alloy, wherein the deformable membrane is embossed by hot forming above a transition temperature of the shape memory alloy to form raised regions having lateral dimensions comprising a length and a width that are not less than the lateral dimensions of an integrated circuit package.

Assignees

• Intel Corp

Inventors

• Lofgreen Kelly
• Petrini Joseph
• Coons Todd
• Ackerman Christopher Wade
• Cetegen Edvin
• Jiao Yang
• Rutigliano Michael
• Liu Kuang

Classifications

• H05K7/20454 Primary

  with a conformable or flexible structure compensating for irregularities, e.g. cushion bags, thermal paste · CPC title

• H05K7/20254 Primary

  Cold plates transferring heat from heat source to coolant · CPC title

• H05K7/20927

  Liquid coolant without phase change · CPC title