Power surface mount light emitting die package

• US 8,188,488 B2
• Filed: 03/22/2007
• Issued: 05/29/2012
• Est. Priority Date: 05/27/2003
• Status: Active Grant

• Current Assignee: Creeled Incorporated
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Andrews, Peter Scott, Loh, Ban P.
• Primary Examiner(s): Pizarro, Marcos D.
• Assistant Examiner(s): MONTALVO, EVA Y
• Application Number:
  US11/689,868
• Publication Number:
  US 20070200127A1
• Time in Patent Office: 1,895 Days
• Field of Search: 257/98, 257/99, 257/100, 257/81, 257/691, 257/700, 257/706, 257/680, 257/E33.056
• US Class Current: 257/81
• 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 and a second surface opposite the first surface,

a via hole through the substrate, wherein an internal surface of the via hole is coated with an insulating film coating;

a conductive lead extending from the first surface to the second surface, the conductive lead insulated from the substrate by an insulating film, the insulating film being the same or different than the insulating film coating on the internal surface of the via hole;

a metal contact pad on one of the first and second surfaces electrically connected to the conductive lead, the metal contact pad having a light emitting diode (LED) mounted thereon;

a conductive trace on the top surface of the substrate, the conductive trace comprising electrically conductive material and extending from the metal contact pad to a side edge of the substrate; and

a reflector attached to the top surface of the substrate, the reflector substantially surrounding the metal contact pad while leaving other portions of the top surface of the substrate and portions of the conductive trace exposed.

2. The package of claim 1, wherein the via hole includes a conductive trace therethrough that is insulated from the substrate by the insulating film coating and is in electrical contact with the conductive lead.

3. The package of claim 1, wherein the reflector plate comprises at least one leg mechanically engaging the substrate for increased thermal transfer.

4. The package of claim 1, wherein the substrate comprises flanges along at least one side for mechanically engaging the reflector plate.

5. The package of claim 1, wherein the reflector plate is composed of a material having high thermal conductivity.

6. The package of claim 1, further comprising:

a lens substantially covering the metal contact pad.

7. The package of claim 6, wherein the lens includes a trough adapted to receive optical chemicals.

8. The package of claim 6, wherein the lens includes materials selected from the group consisting of frequency shifting compounds, a diffusant, and a phosphor.

9. A light emitting die package comprising:

a substrate having a first surface and a second surface opposite the first surface;

a first conductive trace on the first surface that is insulated from the substrate by a first insulating film, the first conductive trace forming a mounting pad for mounting a light emitting device and extending from the mounting pad to a side edge of the substrate;

at least one via hole formed through the substrate, an internal surface of the via hole being coated with a second insulating film; and

a reflector attached to the first surface of the substrate, the reflector substantially surrounding the mounting pad while leaving other portions of the first surface of the substrate and portions of the first conductive trace exposed.

10. The package of claim 9, further comprising:

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

11. The package of claim 10, wherein the at least one via hole includes a conductive trace there through, the conductive trace being insulated from the substrate by the second insulating film and being in electrical contact with one of the first and second conductive traces.

12. The package of claim 10, wherein the LED is encapsulated within optically clear polymer.

13. The package of claim 9, further comprising:

a second trace electrically connected to the first conductive trace and extending away from the first surface.

14. The package of claim 9, wherein one of the first and second insulating films comprises a ceramic polymer film.

15. The package of claim 9, wherein the substrate comprises one of a ceramic or a metal selected from the group consisting of copper, aluminum and a copper/aluminum alloy.

16. The package of claim 9, further comprising:

a second conductive trace on the first surface electrically connected to the first conductive trace, wherein one of the first and second traces extends away from the mounting pad and around a side of the substrate and the reflector substantially surrounding the mounting pad while leaving other portions of the first surface of the substrate and portions of the first and second conductive traces exposed.

17. The package of claim 9, wherein the reflector plate comprises at least one leg mechanically engaging the substrate for increased thermal transfer.

18. The package of claim 9, wherein the substrate comprises flanges along at least one side for mechanically engaging the reflector plate.

19. The package of claim 9, wherein the reflector plate is composed of a material having high thermal conductivity.

20. The package of claim 9, further comprising:

a lens substantially covering the mounting pad.

21. The package of claim 20, wherein the lens includes a trough adapted to receive optical chemicals.

22. The package of claim 20, wherein the lens includes materials selected from the group consisting of frequency shifting compounds, a diffusant, and a phosphor.

23. The package of claim 9, wherein the substrate is composed of a material which is both thermally conductive and electrically conductive.

24. A light emitting die package comprising:

a substrate having a top surface and a bottom surface,

a plurality of conductive traces on the top surface connected to a light emitting device and each conductive trace extending to a side edge of the substrate and at least one conductive element attached to the bottom surface;

at least two via holes formed through the substrate, an internal surface of each via hole being coated with an insulating material, each via hole including an electrical conductor therein which electrically connects the conductive traces on the top surface with the at least one conductive element on the bottom surface of the substrate; and

a reflector attached to the top surface of the substrate, the reflector surrounding the light emitting device while leaving other portions of the top surface of the substrate and portions of the conductive traces exposed.

25. The package of claim 24, wherein the insulating material is a ceramic/polymer film.

26. The package of claim 24, wherein at least one conductive trace on the top surface forms a mounting pad for mounting the light emitting device.

27. The package of claim 26,

further comprising a light emitting diode (LED) mounted on the mounting pad and connected to the first and second conductive traces.

28. The package of claim 24, wherein the plurality of conductive traces is insulated from the substrate by an insulating film, the insulating film being the same or different than the insulating material on the internal surface of the via hole.

29. The package of claim 24, wherein

the plurality of conductive traces on the top surface includes a first conductive trace forming a mounting pad for mounting the light emitting device and a second conductive trace electrically connected to the light emitting device,

the at least one conductive element on the bottom surface includes a bond pad electrically connected to the first conductive trace by an electrical conductor in one via hole, and a solder pad electrically connected to the second conductive trace by an electrical conductor in another via hole.

30. A light emitting die package, comprising:

a substrate having a first surface and a second surface opposite the first surface;

a via hole through the substrate;

a conductive lead extending from the first surface to the second surface, the conductive lead insulated from the substrate by an insulating film;

a metal contact pad on one of the first and second surfaces electrically connected to the conductive lead, the metal contact pad having a light emitting diode (LED) mounted thereon;

a reflector coupled to said substrate and substantially surrounding the mounting pad and said reflector including a ledge formed therein;

an encapsulation material for encapsulating the light emitting diode, the encapsulation material residing within the reflector 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 reflector.

31. The package of claim 30, wherein a surface of the via hole is coated with an insulating film coating, the via hole including a conductive trace there through that is insulated from the substrate by the insulating film coating and is in electrical contact with the conductive lead.

32. A semiconductor die package, comprising:

a substrate having a top surface;

an insulating film covering at least a portion of the top surface of the substrate;

a pair of conductive traces on the insulating film and insulated from the top surface of the substrate by the insulating film, one of the traces of the pair including a trace portion that serves as a mounting pad for mounting a light emitting die (LED) thereon;

a reflector plate coupled to the substrate and substantially surrounding the LED and mounting pad, the reflector plate including an opening and a ledge within the opening, and

a lens coupled on the ledge of the reflector plate within the opening.

33. The semiconductor die package of claim 32, wherein the reflector plate further defines a reflection surface.

34. The semiconductor die package of claim 32, wherein the lens substantially covers the mounting pad and LED, the package further comprising an encapsulant covering the LED within at least part of the opening, the lens adhering to the encapsulant so that the lens floats on the encapsulant within the opening.

35. The semiconductor die package of claim 32, wherein the reflector plate and substrate serve as corresponding top and bottom heat sinks for removing heat away from the LED during package operation.