Power surface mount light emitting die package

• US 8,530,915 B2
• Filed: 02/07/2011
• Issued: 09/10/2013
• Est. Priority Date: 09/04/2002
• Status: Expired due to Term

• Current Assignee: Creeled Incorporated
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Andrews, Peter Scott, Loh, Ban P.
• Primary Examiner(s): Weiss, Howard
• Assistant Examiner(s): Rao, Steven
• Application Number:
  US13/022,365
• Publication Number:
  US 20110121345A1
• Time in Patent Office: 946 Days
• Field of Search: 257/98, 257/99, 257/E33.072, 438/108, 438/26, 438/28, 438/43
• US Class Current: 257/96
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• 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 2924/0102 Calcium [Ca]
• CPC Class Codes: H01L 2924/01025 Manganese [Mn]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/52 Encapsulations
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/58 Optical field-shaping elements
• CPC Class Codes: H01L 33/60 Reflective elements
• 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 33/64 Heat extraction or cooling elements
• CPC Class Codes: H01L 33/641 characterized by the materials
• CPC Class Codes: H01L 33/642 characterized by the shape
• CPC Class Codes: H01L 33/647 the elements conducting electric current to or from the semiconductor body

Abstract

A light emitting die package is provided which includes a metal substrate having a first surface and a first conductive lead on the first surface. The first conductive lead is insulated from the substrate by an insulating film. The first conductive lead forms a mounting pad for mounting a light emitting device. The package includes a metal lead electrically connected to the first conductive lead and extending away from the first surface.

Claims

1. A light emitting die package, comprising:

a substrate having a first surface;

a first conductive lead on the first surface that is insulated from the substrate by an insulating film, the first conductive lead forming a mounting pad for mounting a light emitting device;

a lead electrically connected to the first conductive lead and extending away from the first surface; and

a reflective surface disposed on the first surface of the substrate at least partially on top of the first conductive lead, the reflective surface substantially surrounding the mounting pad while leaving other portions of the first surface of the substrate and portions of the first conductive lead exposed.

2. The package of claim 1, further comprising:

a second conductive lead, and a light emitting diode (LED) mounted on the substrate and connected to the first and second conductive leads.

3. The package of claim 2, wherein the LED is encapsulated within optically clear polymer.

4. The package of claim 1, wherein the substrate comprises a metal selected from the group consisting of copper, aluminum and a copper/aluminum alloy.

5. The package of claim 1, wherein the insulating film comprises a ceramic polymer film.

6. The package of claim 2, wherein the substrate comprises a second surface opposite the first surface, and further comprising at least one via hole through the substrate.

7. The package of claim 6, wherein a surface of the via hole is coated with an insulating film coating.

8. The package of claim 6, wherein the via hole includes a conductive trace there through, the conductive trace being insulated from the substrate by the insulating film coating, being in electrical contact with one of the first and second conductive leads.

9. The package of claim 1, wherein the lead electrically connected to the first conductive lead extends away from the mounting pad and around a side of the substrate.

10. The package of claim 1, wherein the reflective surface is disposed on a reflector that comprises at least one leg mechanically engaging the substrate for increased thermal transfer.

11. The package of claim 1, wherein the substrate comprises flanges along at least one side for mechanically engaging a reflector on which the reflective surface resides.

12. The package of claim 1, wherein the reflective surface comprises a material having high thermal conductivity.

13. The package of claim 1, further comprising:

a lens substantially covering the mounting pad.

14. The package of claim 13, wherein the lens comprises a trough adapted to receive optical chemicals.

15. The package of claim 13, wherein the lens comprises materials selected from the group consisting of frequency shifting compounds, a diffusant, and a phosphor.

16. A light emitting die package comprising:

a substrate;

a first conductive element on the substrate;

a second conductive element on the substrate, the second conductive element spaced apart from the first conductive element and at least one of the first and second conductive elements comprising a mounting pad for mounting a light emitting die thereon;

a reflective surface coupled to the substrate and substantially surrounding the mounting pad and the reflective surface comprising a ledge; and

an encapsulation material comprising an optically clear polymer for encapsulating the light emitting die, the encapsulation material residing within the reflective surface over the mounting pad and ledge; and

a lens substantially covering the mounting pad and resting on the encapsulation material above the ledge of the reflective surface.

17. The light emitting die package of claim 16 further comprising a light emitting diode (LED) mounted on the substrate and connected to the first and second conductive elements.

18. The light emitting die package of claim 16, wherein the first and second conductive elements comprise metal traces.

19. The light emitting die package of claim 16, wherein the substrate comprises a metal selected from the group consisting of copper and aluminum.

20. The light emitting die package of claim 16, wherein the substrate comprises a metal consisting of a copper/aluminum alloy.

21. The light emitting die package of claim 16, wherein the substrate comprises a second surface opposite the first surface, and further comprising at least one via hole through the substrate.

22. The light emitting die package of claim 16, wherein the surface of the via hole is coated with an insulating film coating.

23. The light emitting die package of claim 22, wherein the via hole comprises a conductive trace therethrough, the conductive trace is insulated from the substrate by the insulating film coating, and the conductive trace is in electrical contact with one of the first and second conductive elements.

24. The light emitting die package of claim 23, wherein the second surface of the substrate comprises a thermally conductive insulating film on at least a portion of the second surface and wherein the package further comprises a third conductive element on the second surface, the third conductive element is insulated from the substrate by the thermally conductive insulating film, and the third conductive element is in electrical contact with the conductive trace through the via hole.

25. The light emitting die package of claim 16, further comprising an external heat sink coupled to the substrate.

26. The light emitting die package of claim 25, wherein the substrate has a bottom side plated with metals for coupling with the external heat sink.

27. The light emitting die package of claim 16, wherein at least one conductive element extends from the mounting pad to a side of the substrate.

28. The light emitting die package of claim 16, wherein the reflective surface resides on a reflector that is coupled to the substrate.

29. The light emitting die package of claim 28, wherein the substrate comprises flanges along at least one side for mechanically engaging the reflector.

30. The light emitting die package of claim 28, wherein the reflector comprises a material selected from the group consisting of aluminum, copper, ceramics and plastics.

31. The light emitting die package of claim 28, wherein the reflector comprises at least one leg mechanically engaging the substrate for increased thermal transfer.

32. The light emitting die package of claim 16, wherein the lens comprises diffusant.

33. The light emitting die package of claim 16, wherein the lens comprises a phosphor.