White Light Apparatus and Method

• US 20110186874A1
• Filed: 02/02/2011
• Published: 08/04/2011
• Est. Priority Date: 02/03/2010
• Status: Abandoned Application

• Current Assignee: Soraa, Inc.
• Original Assignee: Soraa, Inc.
• Inventors: Shum, Frank Tin Chung
• Application Number:
  US13/019,897
• Publication Number:
  US 20110186874A1
• Time in Patent Office: Days
• US Class Current: 257/88
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: F21K 9/232 specially adapted for generating an essentially omnidirectional light distribution, e.g. with a glass bulb
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• 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 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 33/60 Reflective elements

Abstract

A method of manufacturing LED devices using substrate scale processing includes providing a substrate member having a surface region. A reflective layer is disposed on the surface region, the reflective surface having a reflectivity of at least 85%, An array of conductive regions is spatially disposed on the reflective surface. LED devices are affixed to each of the array regions.

Claims

1. A method of manufacturing LED devices using substrate scale processing, the method comprising:

providing a substrate member having a surface region;

forming a reflective surface on the surface region, the reflective surface being characterized by a reflectivity of at least 85%;

forming an array of regions spatially disposed over the reflective surface; and

providing a plurality of LED devices, individual ones of which are disposed on corresponding ones of the array of regions.

2. The method of claim 1 wherein the substrate member comprises a silicon substrate.

3. The method of claim 1 wherein the reflective surface comprises a silver or aluminum material.

4. The method of claim 1 wherein the array of regions comprises an N by M array, where N is an integer of at least 2 and M is an integer of at least 1.

5. The method of claim 1 wherein each LED device comprises gallium and nitrogen formed from bulk substrate material.

6. The method of claim 1 further comprising encapsulating each of the plurality of LED devices with an encapsulating material comprising a wavelength conversion material.

7. The method of claim 6 wherein the wavelength conversion material comprises at least one of a phosphor, a semiconductor, and a luminescent material.

8. The method of claim 1 wherein the step of forming a reflective surface comprises depositing a silver material or aluminum over the surface region.

9. The method of claim 1 wherein the step of forming a reflective surface comprises:

forming a reflective metal material over the surface region;

forming at least one dielectric material over the metal material; and

forming a plurality of electrically conductive array regions over dielectric material

10. The method of claim 1 wherein the step of forming a reflective surface comprises:

forming a dielectric material over the substrate surface region; and

forming a plurality of electrically conductive reflective array regions over the dielectric material.

11. The method of claim 1 wherein the step of forming a reflective surface comprises:

forming a dielectric material over the substrate surface region;

forming a plurality of electrically conductive array regions over the dielectric material; and

forming a electrically insulating but optically reflective layer on top one portion of dielectric material or electrically conductive array region.

12. A light emitting diode apparatus comprising:

a substrate member having a surface region;

a reflective layer overlaying the surface region, the reflective layer having a first reflectivity level;

an isolation layer overlying the reflective layer;

an array of regions disposed on the isolation layer;

a plurality of LED devices disposed on corresponding ones of the array regions.

13. The apparatus of claim 12 wherein each of the array of regions includes a conductive pattern.

14. The apparatus of claim 12 wherein the reflective layer and the isolation layer have a combined reflectivity of greater than 93%.

15. The apparatus of claim 12 wherein the substrate has a conductivity of greater than 40 W/(m-K).

16. The apparatus of claim 12 wherein the isolation layer comprises SiN material.

17. An LED apparatus comprising:

a substrate having a surface region;

a reflective layer overlying the surface region, the reflective layer being characterized by a first reflectivity level;

an isolation layer over the reflective layer;

an array of conductive regions disposed on the isolation layer;

a plurality of LED devices, individual ones of which are positioned on each of the array regions; and

a cover member overly the plurality of LED devices.

18. The apparatus of claim 17 further comprising a rectifier circuit coupled to the array of conductive regions.

19. The apparatus of claim 18 further comprising a resistor electrically coupled to the rectifier circuit.

20. The apparatus of claim 17 wherein the plurality of LED devices include a first LED set and a second LED set, each of the LED sets including a plurality of LED devices connected in series, the first LED set and the second LED set being configured in parallel to each other.