Heat spreader having thermal interface material retainment

Patent metadata

Field	Value
Publication number	US-10079191-B2
Application number	US-201514928765-A
Country	US
Kind code	B2
Filing date	Oct 30, 2015
Priority date	Oct 16, 2015
Publication date	Sep 18, 2018
Grant date	Sep 18, 2018

Abstract

In embodiments described herein, an integrated circuit (IC) package is provided. The IC package may include a substrate, an IC die, and a heat spreader. The IC die may have opposing first and second surfaces, where the first surface of the IC die is coupled to a surface of the substrate. The heat spreader may have a surface coupled to the second surface of the IC die by a thermal interface (TI) material. The surface of the heat spreader may have a micro-recess which may include a micro-channel or a micro-dent to direct a flow of TI material towards or away from a predetermined area of the second surface of the IC die based on temperatures of the substrate, the IC die, and/or the heat spreader.

First claim

What is claimed is:

1. An integrated circuit (IC) package, comprising:
a substrate having a first surface;
an IC die having opposing first and second surfaces, the first surface of the IC die coupled to the first surface of the substrate; and
a heat spreader having a first surface coupled to the second surface of the IC die by a thermal interface (TI) material, the first surface of the heat spreader including a micro-recess configured to affect a flow of TI material towards or away from a predetermined area of the second surface of the IC die based on a temperature of the substrate, the IC die, or the heat spreader,
wherein the micro-recess includes a textured surface having a flow resistance for the TI material flowing towards the predetermined area that is less than a flow resistance for the TI material flowing away from the predetermined area.

2. The IC package of claim 1 , wherein the micro-recess is a micro-channel on the first surface of the heat spreader configured to direct the flow of the TI material towards or away from the predetermined area.

3. The IC package of claim 2 , wherein the micro-channel extends from the predetermined area of the second surface of the IC die to or beyond an edge of the second surface of the IC die.

4. The IC package of claim 2 , wherein the micro-channel is formed into a shape on the first surface of the heat spreader.

5. The IC package of claim 2 , wherein the micro-channel includes a shaped micro-channel and a straight micro-channel.

6. The IC package of claim 5 , wherein the straight micro-channel intersects with the shaped micro-channel.

7. The IC package of claim 5 , wherein the straight micro-channel connects to the shaped micro-channel and extends to or beyond an edge of the second surface of the IC die.

8. The IC package of claim 2 , wherein a cross-sectional shape of the micro-channel is one of a V-shape, a half oval shape, a rectangular shape, or a trapezoidal shape.

9. The IC package of claim 2 , wherein a cross-sectional depth of the micro-channel is less than half a cross-sectional height of the heat spreader.

10. The IC package of claim 1 , wherein the predetermined area of the second surface of the IC die is an area having a known thermal hotspot.

11. The IC package of claim 1 , wherein the micro-recess is formed by a surface removal method.

12. The IC package of claim 1 , wherein the micro-recess extends from an outer portion of the predetermined area of the second surface of the IC die to or beyond an edge of the second surface of the IC die.

13. The IC package of claim 1 , wherein the micro-recess is a micro-dent configured to store the TI material.

14. The IC package of claim 13 , wherein the micro-dent is one of a conical shape, an oval shape, or a rectangular shape.

15. The IC package of claim 1 , wherein the micro-recess is a micro-channel connected to a micro-dent.

16. The IC package of claim 1 , wherein the micro-recess is arranged in a pattern based on a location of a predetermined thermal hotspot of the second surface of the IC die and the micro-recess facilitates retention of the TI material at the location of the predetermined thermal hotspot.

17. An integrated circuit (IC) package, comprising:
an IC die;
thermal interface (TI) material; and
a heat spreader comprising a first surface configured to couple to a surface of the IC die through the TI material, the first surface of the heat spreader comprising a micro-recess configured to direct a flow of the TI material towards or away from a predetermined area of the IC die based on a temperature of the IC die and the heat spreader,
wherein the micro-recess includes a textured surface having a flow resistance for the TI material flowing towards the predetermined area that is less than a flow resistance for the TI material flowing away from the predetermined area.

18. The IC package of claim 17 , wherein the micro-recess is a micro-channel.

19. The IC package of claim 17 , wherein the micro-recess is a micro-dent.

20. The IC package of claim 17 , further comprising:
a reservoir of the TI material disposed along an edge of the IC die and aligned with an end of the micro-recess.

Assignees

• Avago Technologies General Ip

Inventors

• Zhao Sam Ziqun
• Khan Rezaur Rahman

Classifications

• H10W90/736

  between a chip and a stacked lead frame, conducting package substrate or heat sink · CPC title

• H10W90/734

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W90/724

  between a chip and a stacked insulating package substrate, interposer or RDL · CPC title

• H10W76/67

  characterised by their materials · CPC title

• H10W74/15

  on active surfaces of flip-chip devices, e.g. underfills · CPC title