Method of making a semiconductor chip assembly with a post/base heat spreader and a signal post

• US 7,951,622 B2
• Filed: 12/21/2009
• Issued: 05/31/2011
• Est. Priority Date: 03/25/2008
• Status: Active Grant

• Current Assignee: Bridge Semiconductor Corporation
• Original Assignee: Bridge Semiconductor Corporation
• Inventors: Lin, Charles W. C., Wang, Chia-Chung
• Primary Examiner(s): Graybill; David E
• Application Number:
  US12/642,859
• Publication Number:
  US 20100167436A1
• Time in Patent Office: 526 Days
• Field of Search: None
• US Class Current: 438/26
• CPC Class Codes: H01L 21/486 Via connections through the substrate with or without pins
• CPC Class Codes: H01L 2224/32013 the layer connector being larger than the bonding area, e.g. bond pad
• 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 2224/45144 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 23/3677 Wire-like or pin-like cooling fins or heat sinks
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/19041 being a capacitor
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• 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 2201/09054 : Raised area or protrusion of metal substrate
• CPC Class Codes: H05K 2201/10106 : Light emitting diode [LED]
• CPC Class Codes: H05K 2203/0369 : Etching selective parts of a metal substrate through part of its thickness, e.g. using etch resist
• CPC Class Codes: H05K 3/0061 : onto a metallic substrate, e.g. a heat sink heat sinks for electric apparatus H05K7/20

Abstract

A method of making a semiconductor chip assembly includes providing a thermal post, a signal post and a base, mounting an adhesive on the base including inserting the thermal post into a first opening in the adhesive and the signal post into a second opening in the adhesive, mounting a conductive layer on the adhesive including aligning the thermal post with a first aperture in the conductive layer and the signal post with a second aperture in the conductive layer, then flowing the adhesive into and upward in a first gap located in the first aperture between the thermal post and the conductive layer and in a second gap located in the second aperture between the signal post and the conductive layer, solidifying the adhesive, then providing a conductive trace that includes a pad, a terminal, the signal post and a selected portion of the conductive layer, mounting a semiconductor device on a heat spreader that includes the thermal post and the base, electrically connecting the semiconductor device to the conductive trace and thermally connecting the semiconductor device to the heat spreader.

Claims

1. A method of making a semiconductor chip assembly, comprising:

providing a thermal post, a signal post, a base, an adhesive and a conductive layer, wherein

the thermal post is adjacent to the base, extends above the base in an upward direction, extends into a first opening in the adhesive and is aligned with a first aperture in the conductive layer,

the signal post is adjacent to the base, extends above the base in the upward direction, extends into a second opening in the adhesive and is aligned with a second aperture in the conductive layer,

the base extends below the posts in a downward direction opposite the upward direction and extends laterally from the posts in lateral directions orthogonal to the upward and downward directions,

the adhesive is mounted on and extends above the base, is sandwiched between the base and the conductive layer and is non-solidified, and

the conductive layer is mounted on and extends above the adhesive;

then

flowing the adhesive into and upward in a first gap located in the first aperture between the thermal post and the conductive layer and in a second gap located in the second aperture between the signal post and the conductive layer;

solidifying the adhesive;

then

providing a conductive trace that includes a pad, a terminal, the signal post and a selected portion of the conductive layer;

mounting a semiconductor device on a heat spreader that includes the thermal post and the base, wherein the semiconductor device overlaps the thermal post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal, wherein an electrically conductive path between the pad and the terminal includes the signal post; and

thermally connecting the semiconductor device to the thermal post, thereby thermally connecting the semiconductor device to the base.

2. The method of claim 1, wherein providing the thermal post, the signal post and the base includes:

providing a metal plate;

forming an etch mask on the metal plate that selectively exposes the metal plate;

etching the metal plate in a pattern defined by the etch mask, thereby forming a recess in the metal plate that extends into but not through the metal plate; and

then

removing the etch mask, wherein the thermal post includes a first unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, the signal post includes a second unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, and the base includes an unetched portion of the metal plate below the posts and the recess.

3. The method of claim 1, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and

solidifying the adhesive includes curing the uncured epoxy.

4. The method of claim 1, wherein flowing the adhesive includes filling the gaps with the adhesive.

5. The method of claim 1, wherein mounting the conductive layer includes mounting the conductive layer alone on the adhesive.

6. The method of claim 1, wherein providing the pad includes removing selected portions of the conductive layer after solidifying the adhesive.

7. The method of claim 1, wherein providing the terminal includes removing selected portions of the base after solidifying the adhesive.

8. The method of claim 1, including providing a cap on the thermal post that extends above and is adjacent to and covers in the upward direction and extends laterally in the lateral directions from a top of the thermal post and that overlaps and is adjacent to the adhesive after solidifying the adhesive and before mounting the semiconductor device, wherein the heat spreader includes the cap.

9. The method of claim 1, wherein mounting the semiconductor device includes providing a first solder joint between the semiconductor device and the pad and a second solder joint between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing the first solder joint between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the second solder joint between the semiconductor device and the heat spreader.

10. The method of claim 1, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the heat spreader.

11. A method of making a semiconductor chip assembly, comprising:

providing a thermal post, a signal post and a base, wherein the thermal post is adjacent to and integral with the base and extends above the base in an upward direction, the signal post is adjacent to and integral with the base and extends above the base in the upward direction, and the base extends below the posts in a downward direction opposite the upward direction and extends laterally from the posts in lateral directions orthogonal to the upward and downward directions;

providing an adhesive, wherein first and second openings extend through the adhesive;

providing a conductive layer, wherein first and second apertures extend through the conductive layer;

mounting the adhesive on the base, including inserting the thermal post into the first opening and the signal post into the second opening, wherein the adhesive extends above the base, the thermal post extends into the first opening and the signal post extends into the second opening;

mounting the conductive layer on the adhesive, including aligning the thermal post with the first aperture and the signal post with the second aperture, wherein the conductive layer extends above the adhesive and the adhesive is sandwiched between the base and the conductive layer and is non-solidified;

then

applying heat to melt the adhesive;

moving the base and the conductive layer towards one another, thereby moving the thermal post upward in the first aperture, moving the signal post upward in the second aperture and applying pressure to the molten adhesive between the base and the conductive layer, wherein the pressure forces the molten adhesive to flow into and upward in a first gap located in the first aperture between the thermal post and the conductive layer and in a second gap located in the second aperture between the signal post and the conductive layer;

applying heat to solidify the molten adhesive, thereby mechanically attaching the posts and the base to the conductive layer;

then

providing a conductive trace that includes a pad, a terminal, a routing line and the signal post, wherein the conductive trace includes a selected portion of the conductive layer and an electrically conductive path between the pad and the terminal includes the routing line and the signal post;

mounting a semiconductor device on a heat spreader that includes the thermal post and the base, wherein the semiconductor device overlaps the thermal post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the thermal post, thereby thermally connecting the semiconductor device to the base.

12. The method of claim 11, wherein providing the thermal post, the signal post and the base includes:

providing a metal plate;

forming an etch mask on the metal plate that selectively exposes the metal plate;

etching the metal plate in a pattern defined by the etch mask, thereby forming a recess in the metal plate that extends into but not through the metal plate; and

then

removing the etch mask, wherein the thermal post includes a first unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, the signal post includes a second unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, and the base includes an unetched portion of the metal plate below the posts and the recess.

13. The method of claim 11, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and

solidifying the adhesive includes curing the uncured epoxy.

14. The method of claim 11, wherein providing the pad and the routing line includes removing selected portions of the conductive layer using an etch mask that defines the pad and the routing line after solidifying the adhesive.

15. The method of claim 11, wherein providing the pad and the routing line includes:

grinding the posts, the adhesive and the conductive layer such that the posts, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that faces in the upward direction; and

then

removing selected portions of the conductive layer using an etch mask that defines the pad and the routing line.

16. The method of claim 15, wherein providing the pad, the routing line and a cap includes:

grinding the posts, the adhesive and the conductive layer such that the posts, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that faces in the upward direction;

then

depositing a second conductive layer on the posts, the adhesive and the conductive layer;

forming an etch mask on the second conductive layer;

etching the conductive layers using the etch mask to define the pad and the routing line;

etching the second conductive layer using the etch mask to define the cap; and

then

removing the etch mask, wherein the heat spreader includes the cap.

17. The method of claim 11, wherein providing the terminal includes removing selected portions of the base after solidifying the adhesive.

18. The method of claim 11, wherein providing the terminal includes:

forming an etch mask after solidifying the adhesive and before mounting the semiconductor device;

etching the base in a pattern defined by the etch mask; and

then

removing the etch mask, wherein the terminal includes an unetched portion of the base that is adjacent to the signal post and is spaced and separated from and no longer part of the base.

19. The method of claim 11, wherein mounting the semiconductor device includes mounting an LED package that includes an LED chip on the pad using a first solder joint and on the heat spreader using a second solder joint, electrically connecting the semiconductor device includes providing the first solder joint between the LED package and the pad, and thermally connecting the semiconductor device includes providing the second solder joint between the LED package and the heat spreader.

20. The method of claim 11, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the heat spreader.

21. A method of making a semiconductor chip assembly, comprising:

providing a thermal post, a signal post and a base, wherein the thermal post is adjacent to and integral with the base and extends above the base in an upward direction, the signal post is adjacent to and integral with the base and extends above the base in the upward direction, and the base extends below the posts in a downward direction opposite the upward direction and extends laterally from the posts in lateral directions orthogonal to the upward and downward directions;

providing an adhesive, wherein first and second openings extend through the adhesive;

providing a conductive layer, wherein first and second apertures extend through the conductive layer;

mounting the adhesive on the base, including inserting the thermal post through the first opening and the signal post through the second opening, wherein the adhesive extends above the base, the thermal post extends through the first opening and the signal post through the second opening;

mounting the conductive layer alone on the adhesive, including inserting the thermal post into the first aperture and the signal post into the second aperture, wherein the conductive layer extends above the adhesive, the thermal post extends through the first opening into the first aperture, the signal post extends through the second opening into the second aperture, the adhesive is sandwiched between the base and the conductive layer and is non-solidified, a first gap is located in the first aperture between the thermal post and the conductive layer and a second gap is located in the second aperture between the signal post and the conductive layer;

then

applying heat to melt the adhesive;

moving the base and the conductive layer towards one another, thereby moving the thermal post upward in the first aperture, moving the signal post upward in the second aperture and applying pressure to the molten adhesive between the base and the conductive layer, wherein the pressure forces the molten adhesive to flow into and upward in the gaps;

applying heat to solidify the molten adhesive, thereby mechanically attaching the posts and the base to the conductive layer;

then

providing a conductive trace that includes a pad, a terminal, a routing line and the signal post, including removing selected portions of the conductive layer using a first etch mask that defines the pad and the routing line and removing selected portions of the base using a second etch mask that defines the terminal, wherein the pad and the routing line include selected portions of the conductive layer, the terminal includes an unetched portion of the base that is adjacent to the signal post and is spaced and separated from and no longer part of the base, and an electrically conductive path between the pad and the terminal includes the routing line and the signal post;

then

mounting a semiconductor device on a heat spreader that includes the thermal post and the base, wherein the semiconductor device overlaps the thermal post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the thermal post, thereby thermally connecting the semiconductor device to the base.

22. The method of claim 21, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the conductive layer; and

solidifying the adhesive includes curing the uncured epoxy.

23. The method of claim 21, wherein providing the pad, the routing line and a cap includes:

grinding the posts, the adhesive and the conductive layer such that the posts, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that faces in the upward direction;

then

depositing a second conductive layer on the posts, the adhesive and the conductive layer;

forming the first etch mask on the second conductive layer;

etching the conductive layers using the first etch mask to define the pad and the routing line;

etching the second conductive layer using the first etch mask to define the cap; and

then

removing the first etch mask, wherein the heat spreader includes the cap.

24. The method of claim 21, wherein mounting the semiconductor device includes mounting an LED package that includes an LED chip on the pad using a first solder joint and on the heat spreader using a second solder joint, electrically connecting the semiconductor device includes providing the first solder joint between the LED package and the pad, and thermally connecting the semiconductor device includes providing the second solder joint between the LED package and the heat spreader.

25. The method of claim 21, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the heat spreader.

26. A method of making a semiconductor chip assembly, comprising:

providing a thermal post, a signal post, a base, an adhesive and a substrate, wherein

the substrate includes a conductive layer and a dielectric layer,

the thermal post is adjacent to the base, extends above the base in an upward direction, extends through a first opening in the adhesive and extends into a first aperture in the substrate,

the signal post is adjacent to the base, extends above the base in the upward direction, extends through a second opening in the adhesive and extends into a second aperture in the substrate,

the base extends below the posts in a downward direction opposite the upward direction and extends laterally from the posts in lateral directions orthogonal to the upward and downward directions,

the adhesive is mounted on and extends above the base, is sandwiched between the base and the substrate and is non-solidified,

the substrate is mounted on and extends above the adhesive, and the conductive layer extends above the dielectric layer,

a first gap is located in the first aperture between the thermal post and the substrate, and

a second gap is located in the second aperture between the signal post and the substrate;

then

flowing the adhesive into and upward in the gaps;

solidifying the adhesive;

then

mounting a semiconductor device on a heat spreader that includes the thermal post and the base, wherein the semiconductor device overlaps the thermal post, a conductive trace includes a pad, a terminal, the signal post and a selected portion of the conductive layer and an electrically conductive path between the pad and the terminal includes the signal post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the thermal post, thereby thermally connecting the semiconductor device to the base.

27. The method of claim 26, wherein providing the thermal post, the signal post and the base includes:

providing a metal plate;

forming an etch mask on the metal plate that selectively exposes the metal plate;

etching the metal plate in a pattern defined by the etch mask, thereby forming a recess in the metal plate that extends into but not through the metal plate; and

then

removing the etch mask, wherein the thermal post includes a first unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, the signal post includes a second unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, and the base includes an unetched portion of the metal plate below the posts and the recess.

28. The method of claim 26, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the substrate; and

solidifying the adhesive includes curing the uncured epoxy.

29. The method of claim 26, wherein flowing the adhesive includes filling the gaps with the adhesive.

30. The method of claim 26, wherein mounting the substrate includes contacting the dielectric layer and the adhesive.

31. The method of claim 26, wherein providing the pad includes removing selected portions of the conductive layer after solidifying the adhesive.

32. The method of claim 26, wherein providing the terminal includes removing selected portions of the base after solidifying the adhesive.

33. The method of claim 26, including providing a cap on the thermal post that extends above and is adjacent to and covers in the upward direction and extends laterally in the lateral directions from a top of the thermal post and that overlaps and is adjacent to the adhesive after solidifying the adhesive and before mounting the semiconductor device, wherein the heat spreader includes the cap.

34. The method of claim 26, wherein mounting the semiconductor device includes providing a first solder joint between the semiconductor device and the pad and a second solder joint between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing the first solder joint between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the second solder joint between the semiconductor device and the heat spreader.

35. The method of claim 26, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the heat spreader.

36. A method of making a semiconductor chip assembly, comprising:

providing a thermal post, a signal post and a base, wherein the thermal post is adjacent to and integral with the base and extends above the base in an upward direction, the signal post is adjacent to and integral with the base and extends above the base in the upward direction, and the base extends below the posts in a downward direction opposite the upward direction and extends laterally from the posts in lateral directions orthogonal to the upward and downward directions;

providing an adhesive, wherein first and second openings extend through the adhesive;

providing a substrate that includes a conductive layer and a dielectric layer, wherein first and second apertures extend through the substrate;

mounting the adhesive on the base, including inserting the thermal post through the first opening and the signal post through the second opening, wherein the adhesive extends above the base, the thermal post extends through the first opening and the signal post extends through the second opening;

mounting the substrate on the adhesive, including inserting the thermal post into the first aperture and the signal post into the second aperture, wherein the substrate extends above the adhesive, the conductive layer extends above the dielectric layer, the thermal post extends through the first opening into the first aperture, the signal post extends through the second opening into the second aperture, the adhesive is sandwiched between the base and the substrate and is non-solidified, a first gap is located in the first aperture between the thermal post and the substrate and a second gap is located in the second aperture between the signal post and the substrate;

then

applying heat to melt the adhesive;

moving the base and the substrate towards one another, thereby moving the thermal post upward in the first aperture, moving the signal post upward in the second aperture and applying pressure to the molten adhesive between the base and the substrate, wherein the pressure forces the molten adhesive to flow into and upward in the gaps and the posts and the molten adhesive extend above the dielectric layer;

applying heat to solidify the molten adhesive, thereby mechanically attaching the posts and the base to the substrate;

then

mounting a semiconductor device on a heat spreader that includes the thermal post and the base, wherein the semiconductor device overlaps the thermal post, a conductive trace includes a pad, a terminal, the signal post and a selected portion of the conductive layer and an electrically conductive path between the pad and the terminal includes the signal post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the thermal post, thereby thermally connecting the semiconductor device to the base.

37. The method of claim 36, wherein providing the thermal post, the signal post and the base includes:

providing a metal plate;

forming an etch mask on the metal plate that selectively exposes the metal plate;

etching the metal plate in a pattern defined by the etch mask, thereby forming a recess in the metal plate that extends into but not through the metal plate; and

then

removing the etch mask, wherein the thermal post includes a first unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, the signal post includes a second unetched portion of the metal plate that protrudes above the base and is laterally surrounded by the recess, and the base includes an unetched portion of the metal plate below the posts and the recess.

38. The method of claim 36, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the substrate; and

solidifying the adhesive includes curing the uncured epoxy.

39. The method of claim 36, wherein providing the pad includes removing selected portions of the conductive layer using an etch mask that defines the pad after solidifying the adhesive.

40. The method of claim 36, wherein providing the pad includes:

grinding the posts, the adhesive and the conductive layer such that the posts, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that faces in the upward direction; and

then

removing selected portions of the conductive layer using an etch mask that defines the pad.

41. The method of claim 36, wherein providing the pad and a cap includes:

grinding the posts, the adhesive and the conductive layer such that the posts, the adhesive and the conductive layer are laterally aligned with one another at a top lateral surface that faces in the upward direction;

then

depositing a second conductive layer on the posts, the adhesive and the conductive layer;

forming an etch mask on the second conductive layer;

etching the conductive layers using the etch mask to define the pad;

etching the second conductive layer using the etch mask to define the cap; and

then

removing the etch mask, wherein the heat spreader includes the cap.

42. The method of claim 36, wherein providing the terminal includes removing selected portions of the base after solidifying the adhesive.

43. The method of claim 36, wherein providing the terminal includes:

forming an etch mask after solidifying the adhesive and before mounting the semiconductor device;

etching the base in a pattern defined by the etch mask; and

then

removing the etch mask, wherein the terminal includes an unetched portion of the base that is adjacent to the signal post and is spaced and separated from and no longer part of the base.

44. The method of claim 36, wherein mounting the semiconductor device includes mounting an LED package that includes an LED chip on the pad using a first solder joint and on the heat spreader using a second solder joint, electrically connecting the semiconductor device includes providing the first solder joint between the LED package and the pad, and thermally connecting the semiconductor device includes providing the second solder joint between the LED package and the heat spreader.

45. The method of claim 36, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the heat spreader, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and the heat spreader.

46. A method of making a semiconductor chip assembly, comprising:

providing a thermal post, a signal post and a base, wherein the thermal post is adjacent to and integral with the base and extends above the base in an upward direction, the signal post is adjacent to and integral with the base and extends above the base in the upward direction, and the base extends below the posts in a downward direction opposite the upward direction and extends laterally from the posts in lateral directions orthogonal to the upward and downward directions;

providing an adhesive, wherein first and second openings extend through the adhesive;

providing a substrate that includes a first conductive layer and a dielectric layer, wherein first and second apertures extend through the substrate;

mounting the adhesive on the base, including inserting the thermal post through the first opening and the signal post through the second opening, wherein the adhesive extends above the base, the thermal post extends through the first opening and the signal post extends through the second opening;

mounting the substrate on the adhesive, including inserting the thermal post into the first aperture and the signal post into the second aperture, wherein the substrate extends above the adhesive, the first conductive layer extends above the dielectric layer, the thermal post extends through the first opening into the first aperture, the signal post extends through the second opening into the second aperture, the adhesive is sandwiched between the base and the substrate and is non-solidified, a first gap is located in the first aperture between the thermal post and the substrate and a second gap is located in the second aperture between the signal post and the substrate;

then

applying heat to melt the adhesive;

moving the base and the substrate towards one another, thereby moving the thermal post upward in the first aperture, moving the signal post upward in the second aperture and applying pressure to the molten adhesive between the base and the substrate, wherein the pressure forces the molten adhesive to flow into and upward in the gaps and the posts and the molten adhesive extend above the dielectric layer;

applying heat to solidify the molten adhesive, thereby mechanically attaching the posts and the base to the substrate;

then

depositing a second conductive layer on the posts, the adhesive and the first conductive layer;

providing a conductive trace that includes a pad, a terminal and the signal post, including removing selected portions of the conductive layers using a first etch mask that defines the pad and removing selected portions of the base using a second etch mask that defines the terminal, wherein the pad includes selected portions of the conductive layers, the terminal includes an unetched portion of the base that is adjacent to the signal post and is spaced and separated from and no longer part of the base, and an electrically conductive path between the pad and the terminal includes the signal post;

providing a cap on the thermal post that includes a selected portion of the second conductive layer, including removing selected portions of the second conductive layer using the first etch mask, wherein the cap extends above and is adjacent to and covers in the upward direction and extends laterally in the lateral directions from a top of the thermal post;

then

mounting a semiconductor device on the cap, wherein a heat spreader includes the thermal post, the base and the cap and the semiconductor device overlaps the thermal post;

electrically connecting the semiconductor device to the pad, thereby electrically connecting the semiconductor device to the terminal; and

thermally connecting the semiconductor device to the cap, thereby thermally connecting the semiconductor device to the base.

47. The method of claim 46, wherein:

providing the adhesive includes providing a prepreg with uncured epoxy;

flowing the adhesive includes melting the uncured epoxy and compressing the uncured epoxy between the base and the substrate; and

solidifying the adhesive includes curing the uncured epoxy.

48. The method of claim 46, wherein providing the pad and the cap includes:

grinding the posts, the adhesive and the first conductive layer such that the posts, the adhesive and the first conductive layer are laterally aligned with one another at a top lateral surface that faces in the upward direction; and

then

depositing the second conductive layer on the posts, the adhesive and the first conductive layer.

49. The method of claim 46, wherein mounting the semiconductor device includes mounting an LED package that includes an LED chip on the pad using a first solder joint and on the cap using a second solder joint, electrically connecting the semiconductor device includes providing the first solder joint between the LED package and the pad, and thermally connecting the semiconductor device includes providing the second solder joint between the LED package and the cap.

50. The method of claim 46, wherein mounting the semiconductor device includes providing a die attach between the semiconductor device and the cap, electrically connecting the semiconductor device includes providing a wire bond between the semiconductor device and the pad, and thermally connecting the semiconductor device includes providing the die attach between the semiconductor device and cap.