High-performance LED fabrication

• US 10,693,041 B2
• Filed: 10/23/2018
• Issued: 06/23/2020
• Est. Priority Date: 09/18/2009
• Status: Active Grant

• Current Assignee: Korrus Incorporated (MKD Electric, Inc.)
• Original Assignee: Soraa, Inc.
• Inventors: Cich, Michael J., David, Aurelien J. F., Hurni, Christophe, Aldaz, Rafael, Krames, Michael Ragan
• Primary Examiner(s): Vu, Jimmy T
• Application Number:
  US16/168,311
• Publication Number:
  US 20190165212A1
• Time in Patent Office: 609 Days
• CPC Class Codes: F21V 29/70 characterised by passive heat-dissipating elements, e.g. heat-sinks
• CPC Class Codes: H01L 2224/14 of a plurality of bump connectors
• CPC Class Codes: H01L 2933/0033 relating to semiconductor body packages
• CPC Class Codes: H01L 2933/0066 relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 33/02 characterised by the semiconductor bodies
• CPC Class Codes: H01L 33/16 with a particular crystal structure or orientation, e.g. polycrystalline, amorphous or porous
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• 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

Abstract

High-performance light-emitting diode together with apparatus and method embodiments thereto are disclosed. The light emitting diode devices emit at a wavelength of 390 nm to 470 nm or at a wavelength of 405 nm to 430 nm. Light emitting diode devices are characterized by having a geometric relationship (e.g., aspect ratio) between a lateral dimension of the device and a vertical dimension of the device such that the geometric aspect ratio forms a volumetric light emitting diode that delivers a substantially flat current density across the device (e.g., as measured across a lateral dimension of the active region). The light emitting diode devices are characterized by having a current density in the active region of greater than about 175 Amps/cm².

Claims

1. An LED package comprising:

a substrate having a substrate top surface;

a plurality of contacts;

a reflective material disposed over at least a portion of said top surface, said reflective material not extending above said plurality of contacts; and

a first plurality of flip-chip LEDs and a second plurality of flip-chip LEDs, each having LED contacts, said LED contacts contacting said plurality of contacts, wherein the first and second pluralities of flip-chip LEDs have different emission colors.

2. The LED package of claim 1, wherein one of the plurality of flip-chip LEDs is blue.

3. The LED package of claim 1, wherein one of the plurality of flip-chip LEDs is violet.

4. The LED package of claim 1, wherein the substrate comprises silicon.

5. The LED package of claim 1, wherein the substrate comprises ceramic.

6. The LED package of claim 1, wherein the reflective material comprises silver and at least one layer of dielectric.

7. The LED package of claim 1, wherein the reflective material comprises TiOx.

8. The LED package of claim 7, wherein the reflective material comprises at least one homogenous layer of TiOx.

9. The LED package of claim 1, further comprising a wavelength-converting material configured over the first and second pluralities of flip-chip LEDs.

10. The LED package of claim 9, wherein the wavelength-converting material is optically coupled to an emission from the first plurality of flip-chip LEDs and the second plurality of flip-chip LEDs.

11. The LED package of claim 10, wherein said wavelength-converting material comprises at least a red phosphor and at least a green phosphor.

12. The LED package of claim 1, wherein the first and second pluralities of flip-chip LEDs are grown on bulk GaN.

13. The LED package of claim 1, wherein said reflective material electrically connects at least a portion of said contacts.

14. The LED package of claim 13, wherein said LED contacts comprise an n-contact and a p-contact, and wherein said reflective material comprises at least a first conductive region and a second conductive region to provide separate electrical connections to each of said n-contact and said p-contact.

15. The LED package of claim 14, wherein the first conductive region and the second conductive region are electrically isolated.

16. The LED package of claim 15, wherein said first and second conductive regions are isolated by a separation street.

17. The LED package of claim 1, further comprising a plurality of traces electrically connecting said contacts.

18. The LED package of claim 17, wherein the plurality of traces comprise copper.

19. The LED package of claim 18, wherein the reflective material comprises TiOx.

20. The LED package of claim 19, wherein the reflective material comprises at least one homogenous layer of TiOx.