Electronic device with heat dissipater

Patent metadata

Field	Value
Publication number	US-9620438-B2
Application number	US-201514615673-A
Country	US
Kind code	B2
Filing date	Feb 6, 2015
Priority date	Feb 14, 2014
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

An electronic device includes an integrated circuit chip mounted to a heat slug. The heat slug has a peripheral region having first thickness along a first direction, the peripheral region surrounding a recess region (having a second, smaller, thickness along the first direction) that defines a chip mounting surface along a second direction perpendicular to the first direction. The recess region defines side borders and a nook extends into the heat slug along the side borders. An insulating body embeds the integrated circuit one chip and heat slug. Material of the insulating body fills the nook.

First claim

What is claimed is:

1. An electronic device, comprising:
at least one chip wherein at least one electronic component is integrated;
an insulating body embedding said at least one chip, the insulating body having a mounting surface configured to mount the electronic device on a board;
a heat slug in contact with said at least one chip and configured to dissipate heat generated by said at least one electronic component toward the mounting surface, the heat slug having a first thickness along a first direction perpendicular to the mounting surface, the heat slug being embedded in said insulating body with a bottom surface exposed from the insulating body at the mounting surface, wherein:
the heat slug is provided with a recess that defines a recessed portion of the heat slug having a second thickness along the first direction smaller than the first thickness;
said recess having a main surface, perpendicular to the first direction and opposed to the bottom surface, and side borders;
said at least one chip is in contact with the main surface of the recess;
said recess comprising nooks extending into said side borders.

2. The electronic device of claim 1 , wherein said side borders are slanted with respect to the first direction.

3. The electronic device of claim 2 , wherein said nooks have a substantially triangular profile along a plane perpendicular to the main surface.

4. The electronic device of claim 1 , wherein the recess has a rectangular shape in plan view and comprises four side borders, the nooks extending inward the heat slug from each one of said side borders being connected to each other to form a continuous nook surrounding the main surface.

5. The electronic device of claim 1 , wherein said recess comprises a plurality of holes extending inward the heat slug from the main surface.

6. The electronic device of claim 5 , wherein the holes are arranged on the main surface to surround said at least one chip.

7. The electronic device of claim 6 , wherein the holes are located at borders of the main surface.

8. The electronic device of claim 1 , wherein the heat slug comprises a groove extending inward the heat slug and surrounding the recess.

9. The electronic device of claim 1 , wherein the electronic device is a power device for power applications, and the at least one chip integrates at least a power MOS transistor.

10. A leadframe for use in manufacturing at least one electronic device, wherein said leadframe comprises a heat slug for each electronic device, said heat slug having a first thickness along a first direction perpendicular to a mounting surface, wherein:
the heat slug is provided with a recess that defines a recessed portion of the heat slug having a second thickness along the first direction smaller than the first thickness;
said recess having a main surface, perpendicular to the first direction and opposed to the bottom surface, and side borders;
said main surface of the recess configured to support an integrated circuit; and
said recess comprising nooks extending into said side borders.

11. The leadframe of claim 10 , wherein said side borders are slanted with respect to the first direction.

12. The leadframe of claim 11 , wherein said nooks have a substantially triangular profile along a plane perpendicular to the main surface.

13. The leadframe of claim 10 , wherein the recess has a rectangular shape in plan view and comprises four side borders, the nooks extending inward the heat slug from each one of said side borders being connected to each other to form a continuous nook surrounding the main surface.

14. The leadframe of claim 10 , wherein said recess comprises a plurality of holes extending inward the heat slug from the main surface.

15. The leadframe of claim 14 , wherein the holes are arranged on the main surface to surround said main surface.

16. The leadframe of claim 14 , wherein the holes are located at borders of the main surface.

17. The leadframe of claim 10 , wherein the heat slug comprises a groove extending inward the heat slug and surrounding the recess.

18. An electronic device, comprising:
an integrated circuit chip;
a heat slug having a peripheral region having a first thickness along a first direction perpendicular to a mounting surface and a recess region surrounded by the peripheral region and having a second thickness along the first direction smaller than the first thickness, the recess region defining a chip mounting surface, the heat slug further including a side border of the recess region extending around the chip mounting surface;
wherein said integrated circuit chip is mounted to said chip mounting surface;
said recess region including a nook extending into said side border at the peripheral region in a second direction perpendicular to the first direction; and
an insulating body embedding said integrated circuit chip and the heat slug, wherein material of the insulating body fills said nook.

19. The device of claim 18 , wherein said nook is defined by a slanted surface.

20. The device of claim 19 , wherein the slanted surface defines a triangular shape for the nook in cross-section taken by a plane perpendicular to the chip mounting surface.

21. The device of claim 18 , wherein the recess region has a rectangular shape in plan view and comprises four side borders, wherein the nook extends from each of said side borders.

22. The device of claim 18 , further comprising a plurality of holes extending into the heat slug in the first direction from the chip mounting surface.

23. The device of claim 18 , further comprising a groove formed in the peripheral region surrounding the recess.

Assignees

• Stmicroelectronics (Malta) Ltd
• St Microelectronics Srl
• St Microelectronics Pte Ltd

Inventors

• Duca Roseanne
• Motta Valter
• Zhang Xueren
• Goh Kim-Yong

Classifications

• H10W90/756

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

• H10W74/127

  characterised by arrangements for sealing or adhesion · CPC title

• H10W72/536

  the connected ends being ball-shaped · CPC title

• H10W40/778 Primary

  in encapsulations · CPC title

• H10W70/461 Primary

  specially adapted for cooling · CPC title