Aligned multiple emitter package

• US 20100155748A1
• Filed: 01/14/2009
• Published: 06/24/2010
• Est. Priority Date: 01/14/2009
• Status: Active Grant

• Current Assignee: Cree Huizhou Solid State Lighting Company Limited (Smart Global Holdings Incorporated)
• Original Assignee: CREE Hong Kong Limited (Wolfspeed, Inc.)
• Inventors: Lau, Yue Kwong Victor, Chan, Chi Keung Alex, Wang, Xuan
• Granted Patent: US 8,368,112 B2
• Time in Patent Office: Days
• US Class Current: 257/89
• CPC Class Codes: H01L 2224/32245 the item being metallic
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 23/49861 Lead-frames fixed on or encapsulated in insulating substrates H01L23/4985, H01L23/49805 take precedence
• CPC Class Codes: H01L 24/73 Means for bonding being of different types provided for in two or more of groups H01L24/10, H01L24/18, H01L24/26, H01L24/34, H01L24/42, H01L24/50, H01L24/63, H01L24/71
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 2924/14 Integrated circuits
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• 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: H01L 33/647 the elements conducting electric current to or from the semiconductor body

Abstract

A multiple element emitter package is disclosed for increasing color fidelity and heat dissipation, improving current control, increasing rigidity of the package assembly. In one embodiment, the package comprises a surface-mount device a casing with a cavity extending into the interior of the casing from a first main surface is provided. A lead frame is at least partially encased by the casing, the lead frame comprising a plurality of electrically conductive parts carrying a linear array of light emitting devices (LEDs). Electrically conductive parts, separate from parts carrying the LEDs have a connection pad, wherein the LEDs are electrically coupled to a connection pad, such as by a wire bond. This lead frame arrangement allows for a respective electrical signal can be applied to each of the LEDs. The emitter package may be substantially waterproof, and an array of the emitter packages may be used in an LED display such as an indoor and/or outdoor LED screen.

Claims

1. An electrically conductive lead frame for a multiple emitter package, comprising:

a plurality of electrically conductive cathode parts each having an attach pad for carrying at least one light emitting device, with each attach pad being electrically coupled to its said at least one light emitting device;

a corresponding plurality of electrically conductive anode parts separate from said cathode parts, each of said anode parts each having a connection pad arranged to allow electrical connection to one of said at least one light emitting device, wherein said attach pads and connection pads are arranged to hold light emitting devices in linear alignment.

2. The lead frame of claim 1, wherein said light emitting devices are adapted to be energized to produce in combination a substantially full range of colors.

3. The lead frame of claim 1, wherein said light emitting devices comprise light emitting diodes (LEDs).

4. The lead frame of claim 3, wherein said LEDs comprise at least two contacts, one of which is electrically coupled to one of said attach pads and the other of which is electrically coupled to one of said connection pads.

5. The lead frame of claim 1, wherein the linear array of light emitting devices extends in a first direction and each of said anode parts are disposed in parallel relationship with each other and said cathode parts are disposed in parallel relationship with each other, and each of which extending in a direction orthogonal to said first direction.

10. The lead frame of claim 1, further comprising a casing of dark and/or black ceramic.

11. The lead frame of claim 1, further comprising through-holes.

12. The lead frame of claim 1, further comprising V-cuts.

6. (canceled)

7. (canceled)

8. (canceled)

9. (canceled)

13. An emitter package, comprising:

a casing comprising a cavity extending into the interior of said casing from a top surface of said casing; and

a lead frame integral to said casing, said lead frame comprising conductive parts holding a plurality of light emitting devices in linear alignment and emitting out said cavity, said lead frame also allowing for an electrical signal to be applied to said light emitting devices through said lead frame.

14. The emitter package of claim 13, wherein said lead frame comprises a plurality of electrically conductive cathode parts each having an attach pad for carrying at least one of said light emitting devices, each said attach pad being electrically coupled to its one of said light emitting devices, and a corresponding plurality of electrically conductive anode parts separate from each said cathode part, each of said anode parts having a connection pad arranged to allow electrical connection to one of said light emitting devices, wherein said attach pads and connection pads are arranged to hold light emitting devices in linear alignment.

15. The emitter package of claim 13, wherein said light emitting devices comprise LEDs, which are adapted to be energized to produce in combination a substantially full range of colors.

16. The emitter package of claim 13, wherein said lead frame is arranged to allow for surface mounting of said package.

17. The device of claim 13, wherein said lead frame further comprises through-holes and/or V-cuts, said holes and cuts improving the overall stability of the surface mount device and enabling it to be substantially waterproof.

18. The device of claim 13, further comprising a thermally conductive body extending at least partially through said carrier.

20. The device of claim 13, wherein said second electrical terminal of each of said light emitters is electrically coupled to a connection pad by a wire bond.

19. (canceled)

21. (canceled)

22. (canceled)

23. (canceled)

24. (canceled)

25. (canceled)

26. (canceled)

27. (canceled)

28. (canceled)

29. An emitter package, comprising:

a casing comprising a cavity extending into the interior of the casing from its top surface; and

a lead frame integral to and bonded to said casing, said lead frame comprising conductive parts holding a plurality of light emitting devices emitting out said casing, said lead frame further comprising features or shapes that cooperate with said casing to provide an improved watertight rigid connection between said lead frame and casing compared to package having a lead frame without said features and shapes.

30. The emitter package of claim 29, wherein said features or shapes comprise through holes in said lead frame.

31. The emitter package of claim 29, wherein said features or shapes comprise V-cuts in said lead frame.

32. The emitter package of claim 29, wherein said features or shapes comprise side indentations.

33. The emitting package of claim 29, wherein said features or shapes comprise side tabs.