Semiconductor chip assembly with post/base heat spreader and cavity in post

• US 8,193,556 B2
• Filed: 02/26/2010
• Issued: 06/05/2012
• Est. Priority Date: 03/25/2008
• Status: Expired due to Fees

• Current Assignee: Bridge Semiconductor Corporation
• Original Assignee: Bridge Semiconductor Corporation
• Inventors: Lin, Charles W. C., Wang, Chia-Chung, Lim, Sangwhoo
• Primary Examiner(s): Nadav, Ori
• Application Number:
  US12/714,413
• Publication Number:
  US 20100155768A1
• Time in Patent Office: 830 Days
• Field of Search: 257/99, 257/706, 257/707, 257/711, 257/712, 257/717
• US Class Current: 257/99
• CPC Class Codes: H01L 21/486 Via connections through the substrate with or without pins
• CPC Class Codes: H01L 21/4882 Assembly of heatsink parts
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/32188 the layer connector connecting to a bonding area protruding from the surface of the item
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2224/85205 Ultrasonic bonding
• CPC Class Codes: H01L 2224/8592 Applying permanent coating, e.g. protective coating
• CPC Class Codes: H01L 23/3677 Wire-like or pin-like cooling fins or heat sinks
• CPC Class Codes: H01L 24/45 of an individual wire connector
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01012 Magnesium [Mg]
• CPC Class Codes: H01L 2924/01019 Potassium [K]
• CPC Class Codes: H01L 2924/01046 Palladium [Pd]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01087 Francium [Fr]
• CPC Class Codes: H01L 2924/15153 : the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/16152 : Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 33/483 : Containers
• CPC Class Codes: H01L 33/62 : Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H01L 33/642 : characterized by the shape
• CPC Class Codes: H05K 1/0204 : using means for thermal conduction connection in the thickness direction of the substrate H05K1/0207 takes precedence
• CPC Class Codes: H05K 1/021 : Components thermally connected to metal substrates or heat-sinks by insert mounting
• CPC Class Codes: H05K 1/182 : associated with components mounted in the printed circuit board, e.g. insert mounted components [IMC]
• CPC Class Codes: H05K 2201/09054 : Raised area or protrusion of metal substrate
• CPC Class Codes: H05K 2201/09745 : Recess in conductor, e.g. in pad or in metallic substrate
• CPC Class Codes: H05K 2201/10106 : Light emitting diode [LED]
• CPC Class Codes: H05K 3/0061 : onto a metallic substrate, e.g. a heat sink heat sinks for electric apparatus H05K7/20

Abstract

A semiconductor chip assembly includes a semiconductor device, a heat spreader, a conductive trace and an adhesive. The heat spreader includes a post and a base. The semiconductor device extends into a cavity in the post, is electrically connected to the conductive trace and is thermally connected to the heat spreader. The post extends upwardly from the base into an opening in the adhesive, and the base extends laterally from the post. The adhesive extends between the post and the conductive trace and between the base and the conductive trace. The conductive trace is located outside the cavity and provides signal routing between a pad and a terminal.

Claims

1. A semiconductor chip assembly, comprising:

a semiconductor device;

an adhesive that includes an opening;

a heat spreader that includes a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, and the base extends below the post in a downward direction opposite the upward direction, covers the post in the downward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions; and

a conductive trace that includes a pad and a terminal;

wherein a cavity in the post faces in the upward direction, extends into the opening, is defined by and laterally surrounded by the post and is covered by the post in the downward direction;

wherein the semiconductor device extends into the cavity and is covered by the cavity in the downward direction, is electrically connected to the pad and thereby electrically connected to the terminal, and is thermally connected to the post and thereby thermally connected to the base;

wherein the adhesive is mounted on and extends above the base, contacts the post and the base, is located outside the cavity, extends between the post and the pad, extends laterally from the post to or beyond the terminal and is sandwiched between the base and the pad;

wherein the conductive trace is located outside the cavity; and

wherein the post extends into the opening and is sandwiched between the base and the cavity and between the adhesive and the cavity, and the base extends below the semiconductor device and the pad.

2. The assembly of claim 1, wherein the semiconductor device is located within the cavity.

3. The assembly of claim 1, wherein the semiconductor device is an LED chip.

4. The assembly of claim 1, wherein the semiconductor device is electrically connected to the pad using a wire bond that extends outside the cavity and is thermally connected to the post using a die attach that is located within the cavity.

5. The assembly of claim 1, wherein the adhesive is located above the base.

6. The assembly of claim 1, wherein the adhesive has a flat top surface at the opening and adjacent to the post and above a bottom surface of the pad.

7. The assembly of claim 1, wherein the adhesive conformally coats sidewalls of the post and a top surface of the base outside the post.

8. The assembly of claim 1, wherein the adhesive contacts the terminal.

9. The assembly of claim 1, wherein the adhesive extends laterally from the post beyond the terminal.

10. The assembly of claim 1, wherein the adhesive extends to peripheral edges of the assembly.

11. The assembly of claim 1, wherein the post is coplanar with the pad.

12. The assembly of claim 1, wherein the post extends above a bottom surface of the pad, does not extend above a top surface of the pad and is coplanar with the adhesive at the base.

13. The assembly of claim 1, wherein the post has a diameter that decreases as it extends upwardly in the opening, and the cavity has a diameter that increases as it extends upwardly in the post.

14. The assembly of claim 1, wherein the base covers the semiconductor device, the adhesive and the conductive trace in the downward direction and extends to peripheral edges of the assembly.

15. The assembly of claim 1, wherein the base and the terminal are the same metallic material, have the same thickness and are coplanar with one another.

16. A semiconductor chip assembly, comprising:

a semiconductor device;

an adhesive that includes an opening;

a heat spreader that includes a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, and the base extends below the post in a downward direction opposite the upward direction, covers the post in the downward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions;

a substrate that includes a dielectric layer, wherein an aperture extends through the substrate; and

a conductive trace that includes a pad and a terminal;

wherein a cavity in the post faces in the upward direction, extends into the opening and the aperture, is defined by and laterally surrounded by the post and is covered by the post in the downward direction;

wherein the semiconductor device is mounted on the post, extends into the cavity and is covered by the cavity in the downward direction, is electrically connected to the pad and thereby electrically connected to the terminal, and is thermally connected to the post and thereby thermally connected to the base;

wherein the adhesive is mounted on and extends above the base, is located outside the cavity, extends into a gap in the aperture between the post and the substrate, extends across the dielectric layer in the gap, contacts and is sandwiched between the post and the dielectric layer in the gap and between the base and the dielectric layer outside the gap and extends laterally from the post to or beyond the terminal;

wherein the substrate is mounted on the adhesive and extends above the base;

wherein the conductive trace is located outside the cavity and the pad is mounted on and extends above the dielectric layer; and

wherein the post extends into the opening and the aperture and is sandwiched between the base and the cavity and between the adhesive and the cavity, and the base extends below the semiconductor device, the adhesive, the substrate and the pad.

17. The assembly of claim 16, wherein the semiconductor device is an LED chip.

18. The assembly of claim 16, wherein the semiconductor device is electrically connected to the pad using a wire bond that extends within and outside the cavity and is thermally connected to the post using a die attach that is located within the cavity.

19. The assembly of claim 16, wherein the adhesive is located above the base.

20. The assembly of claim 16, wherein the adhesive has a flat top surface at the opening and adjacent to the post and above a bottom surface of the pad.

21. The assembly of claim 16, wherein the adhesive fills the gap.

22. The assembly of claim 16, wherein the adhesive conformally coats sidewalls of the post and a top surface of the base outside the post.

23. The assembly of claim 16, wherein the adhesive extends laterally from the post beyond the terminal.

24. The assembly of claim 16, wherein the adhesive extends to peripheral edges of the assembly.

25. The assembly of claim 16, wherein the post is coplanar with the pad above the dielectric layer.

26. The assembly of claim 16, wherein the post extends above a bottom surface of the pad, does not extend above a top surface of the pad and is coplanar with the adhesive below the dielectric layer.

27. The assembly of claim 16, wherein the post has a diameter that decreases as it extends upwardly in the opening, and the cavity has a diameter that increases as it extends upwardly in the post.

28. The assembly of claim 16, wherein the base covers the semiconductor device, the substrate, the adhesive and the conductive trace in the downward direction and extends to peripheral edges of the assembly.

29. The assembly of claim 16, wherein the substrate is spaced from the post and the base and is a laminated structure that includes the pad.

30. The assembly of claim 16, wherein the base and the terminal are the same metallic material, have the same thickness and are coplanar with one another.

31. A semiconductor chip assembly, comprising:

a semiconductor device;

an adhesive that includes an opening;

a heat spreader that includes a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, and the base extends below the post in a downward direction opposite the upward direction, covers the post in the downward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions;

a substrate that includes a dielectric layer, wherein an aperture extends through the substrate;

a conductive trace includes a pad and a terminal; and

an encapsulant;

wherein a cavity in the post faces in the upward direction, extends into the opening and the aperture and below the pad and is located above the base, is defined by and laterally surrounded by the post and is covered by the post in the downward direction;

wherein the semiconductor device is mounted on the post, is located within the cavity, is electrically connected to the pad and thereby electrically connected to the terminal, and is thermally connected to the post and thereby thermally connected to the base;

wherein the adhesive is mounted on and extends above the base, is located outside the cavity, extends into a gap in the aperture between the post and the substrate, extends across the dielectric layer in the gap, contacts and is sandwiched between the post and the dielectric layer within the gap, contacts and is sandwiched between the base and the dielectric layer outside the gap, is sandwiched between the base and the pad outside the gap, extends above a bottom surface of the pad, is overlapped by the pad, extends laterally from the post to or beyond the terminal and extends to peripheral edges of the assembly;

wherein the substrate is mounted on the adhesive, extends above the base and is located outside the cavity;

wherein the conductive trace is located outside the cavity and the pad contacts and extends above the dielectric layer and overlaps the adhesive;

wherein the encapsulant extends into the cavity and covers the semiconductor device in the upward direction; and

wherein the post extends into the opening and the aperture and above and below the dielectric layer, is sandwiched between the base and the cavity and between the adhesive and the cavity and is coplanar with the pad above the dielectric layer and with the adhesive below the dielectric layer, and the base extends below the semiconductor device, the adhesive, the encapsulant, the substrate and the pad.

32. The assembly of claim 31, wherein the semiconductor device is an LED chip, is electrically connected to the pad using a wire bond that extends within and outside the cavity and is thermally connected to the post using a die attach that is located within the cavity.

33. The assembly of claim 31, wherein the substrate is spaced from the post and the base, the adhesive fills the gap and conformally coats sidewalls of the post and a top surface of the base outside the post, and the encapsulant contacts the semiconductor device and the post in the cavity and is spaced from the base.

34. The assembly of claim 31, wherein the post has a diameter that decreases as it extends upwardly from the base to its top surface, and the cavity has a diameter that increases as it extends upwardly from its floor in the post to its entrance at the top surface of the post.

35. The assembly of claim 31, wherein the post is coplanar with the adhesive below the dielectric layer at the base and the cavity extends below the dielectric layer.

36. A semiconductor chip assembly, comprising:

a semiconductor device;

an adhesive that includes an opening;

a heat spreader that includes a post and a base, wherein the post is adjacent to and integral with the base and extends above the base in an upward direction, and the base extends below the post in a downward direction opposite the upward direction, covers the post in the downward direction and extends laterally from the post in lateral directions orthogonal to the upward and downward directions; and

a conductive trace that includes a pad and a terminal;

wherein a cavity in the post faces in the upward direction, extends into the opening, is defined by and laterally surrounded by the post and is covered by the post in the downward direction;

wherein the semiconductor device is mounted on the post, extends into the cavity and is covered by the cavity in the downward direction, is electrically connected to the pad and thereby electrically connected to the terminal, and is thermally connected to the post and thereby thermally connected to the base;

wherein the adhesive is mounted on and extends above the base, contacts the post and the base, is located outside the cavity, is sandwiched between the base and the pad, extends laterally from the post to or beyond the terminal and extends to peripheral edges of the assembly;

wherein the conductive trace is located outside the cavity; and

wherein the post extends into the opening and is coplanar with the pad, and the base extends below the semiconductor device and the pad.

37. The assembly of claim 36, wherein the semiconductor device is located within the cavity, is electrically connected to the pad using a wire bond that extends within and outside the cavity and is thermally connected to the post using a die attach that is located within the cavity.

38. The assembly of claim 36, wherein the adhesive is located above the base, has a flat top surface at the opening and adjacent to the post and above a bottom surface of the pad and conformally coats sidewalls of the post.

39. The assembly of claim 36, wherein the post is coplanar with the terminal.

40. The assembly of claim 36, wherein the post has a diameter that decreases as it extends upwardly in the opening, and the cavity has a diameter that increases as it extends upwardly in the post.

41. The assembly of claim 36, wherein the post extends through an aperture in a dielectric layer that contacts and is sandwiched between the adhesive and the pad, is located below the pad and is spaced from the post and the base, the cavity extends into and above the aperture, the adhesive and the opening extend through the aperture and the adhesive contacts and is sandwiched between the post and the dielectric layer in the aperture and between the base and the dielectric layer outside the aperture.

42. The assembly of claim 36, wherein the cavity extends across a majority of a height and diameter of the post.

43. The assembly of claim 36, wherein the base covers the semiconductor device, the adhesive and the conductive trace in the downward direction and extends to peripheral edges of the assembly.

44. The assembly of claim 36, wherein the post, the base, the pad and the terminal are primarily copper.

45. The assembly of claim 36, wherein the post, the base, the pad and the terminal consist of copper and a plated contact that includes a gold or silver surface layer.