LED chip thermal management and fabrication methods

• US 7,846,751 B2
• Filed: 11/19/2007
• Issued: 12/07/2010
• Est. Priority Date: 11/19/2007
• Status: Active Grant

• Current Assignee: IQE, PLC
• Original Assignee: Wang Nang Wang
• Inventors: Wang, Wang Nang
• Primary Examiner(s): Thai; Luan C
• Application Number:
  US11/942,109
• Publication Number:
  US 20090127567A1
• Time in Patent Office: 1,114 Days
• Field of Search: 438/22, 438/24, 257/79, 257/80, 257/E33.001
• US Class Current: 438/22
• CPC Class Codes: C23C 18/1662 Use of incorporated material in the solution or dispersion, e.g. particles, whiskers, wires
• CPC Class Codes: C25D 15/00 Electrolytic or electrophoretic production of coatings containing embedded materials, e.g. particles, whiskers, wires
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• 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 2933/0075 relating to heat extraction or cooling elements
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/508 having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material
• CPC Class Codes: H01L 33/641 characterized by the materials

Abstract

The present invention relates to a method of fabricating a high power light-emitting device using an electrolessly or electrolytically plated metal composite heat dissipation substrate having a high thermal conductivity and a thermal expansion coefficient matching with the device.

Claims

1. A method for fabricating a thermal expansion coefficient matching substrate for a high power light-emitting device using a metal composite substrate, wherein the metal composite substrate is fabricated by one of either electroless or electrolytic plating of a metal material containing suspended particulates on to a light emitting device.

2. The method according to claim 1, wherein the metal composite substrate comprises metal and thermally conductive nano- and micro-particulates.

3. The method according to claim 1, wherein the metal material is one of either a metal or a metal solution containing suspended particulates.

4. The method according to claim 3, wherein the metal is a metal alloy.

5. The method according to claim 1, wherein the metal composite substrate comprises a metal deposited by electroless plating or electroplating.

6. The according to claim 1, wherein the thermal expansion coefficient of the metal composite substrate is tuned to match the high power light-emitting device by varying the composition of the metal material used.

7. The method according to claim 2, wherein the thermal expansion coefficient of the metal composite substrate is tuned to match the high power light-emitting device by varying one characteristic of the composite of the substrate selected from the group consisting of the composition of the particulate material, the size distribution of the particulates, and the different volume percentages of the particulates.

8. The method according to claim 1, wherein the light-emitting device comprises one of either a vertical p-side down or n-side down device.

9. The method according to claim 1, wherein the light-emitting device comprises a phosphor device to convert light output from the device to a white light.

10. The method according to claim 9, wherein the phosphor device is in the form of multiple layers comprising alternating polymer layers and phosphor layers.

11. The method according to claim 9, wherein the phosphor device is applied directly to the light-emitting device.

12. The method according to claim 9, wherein the phosphor device is a discrete component.

13. The method according to claim 12, wherein the phosphor device comprises various optical patterns to enhance the uniformity of the light output of the light-emitting device.

14. The method according to claim 9, wherein the phosphor device comprises one of either a single material or multiple types of material of different emission wavelength.

15. The method according to claim 10, wherein the phosphor layer of the phosphor device closer to the light-emitting device is thicker.

16. The method according to claim 1, wherein the light-emitting device is mounted into a package containing an electrically insulating and a thermally conducting medium.

17. The method according to claim 16, wherein the medium comprises one of either an electrically insulating and thermally conducting liquid or high thermal conductivity nano- and micro-particles.

18. A high power light-emitting device having a metal composite substrate which comprises a high thermal conductivity and thermal expansion coefficient matching substrate, wherein the substrate includes a metal material containing suspended particulates, the metal material having been electroless or electrolytically plated on to the light emitting device.