Fully reflective and highly thermoconductive electronic module and method of manufacturing the same

• US 8,304,660 B2
• Filed: 04/29/2010
• Issued: 11/06/2012
• Est. Priority Date: 02/07/2008
• Status: Active Grant

• Current Assignee: National Taiwan University (Government of The Republic of China)
• Original Assignee: National Taiwan University (Government of The Republic of China)
• Inventors: Tuan, Wei-Hsing, Lee, Shao-Kuan
• Primary Examiner(s): Smith, Courtney
• Application Number:
  US12/769,889
• Publication Number:
  US 20100212942A1
• Time in Patent Office: 922 Days
• Field of Search: None
• US Class Current: 174/258
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 23/3735 Laminates or multilayers, e.g. direct bond copper ceramic substrates
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/49 of a plurality of wire connectors
• 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 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01L 2924/207 Diameter ranges
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/64 Heat extraction or cooling elements
• CPC Class Codes: H05K 1/0274 Optical details, e.g. printed circuits comprising integral optical means H05K1/0269 takes precedence; coupling light guides with opto-electronic components G02B6/42
• CPC Class Codes: H05K 1/053 the metal substrate being covered by an inorganic insulating layer
• CPC Class Codes: H05K 2201/0108 Transparent
• CPC Class Codes: H05K 2201/10106 : Light emitting diode [LED]
• CPC Class Codes: H05K 2201/2054 : Light-reflecting surface, e.g. conductors, substrates, coatings, dielectrics

Abstract

A fully reflective and highly thermoconductive electronic module includes a metal bottom layer, a transparent ceramic layer and a patterned metal wiring layer. The metal bottom layer has a lower reflective surface. The transparent ceramic layer has an upper surface and a lower surface. The lower surface of the transparent ceramic layer is bonded to the lower reflective surface of the metal bottom layer. The metal wiring layer is bonded to the upper surface of the transparent ceramic layer. The lower reflective surface reflects a first light ray, transmitting through the transparent ceramic layer, to the upper surface of the transparent ceramic layer. A method of manufacturing the fully reflective and highly thermoconductive electronic module is also disclosed.

Claims

1. A fully reflective and highly thermoconductive electronic module, comprising:

a metal bottom layer having a first reflective surface;

a transparent ceramic layer having an upper surface and a lower surface, wherein the lower surface of the transparent ceramic layer is bonded to the first reflective surface of the metal bottom layer; and

a patterned metal wiring layer disposed on the upper surface of the transparent ceramic layer, wherein the first reflective surface reflects a first light ray, transmitting through the transparent ceramic layer, to the upper surface of the transparent ceramic layer, the metal wiring layer has a second reflective surface, the second reflective surface is disposed opposite the first reflective surface the first reflective surface reflects a second light ray, transmitting through the transparent ceramic layer, to the second reflective surface, and the second reflective surface reflects the second light ray to the first reflective surface, which finally reflects the second light ray to transmit through the transparent ceramic layer.

2. The electronic module according to claim 1, wherein the metal wiring layer is bonded to the upper surface of the transparent ceramic layer.

3. The electronic module according to claim 2, wherein the metal bottom layer and the metal wiring layer are made of copper, and a first bonding interface between the metal bottom layer and the transparent ceramic layer is the same as a second bonding interface between the transparent ceramic layer and the metal wiring layer.

4. The electronic module according to claim 1, wherein the transparent ceramic layer is composed of sapphire, glass or silicon oxide.

5. The electronic module according to claim 1, further comprising:

an electrical component, mounted on the upper surface of the transparent ceramic layer or the metal wiring layer, for outputting the first light ray; and

a plurality of wires, electrically connected to the electrical component and the metal wiring layer.

6. The electronic module according to claim 5, wherein the electrical component is mounted on the metal wiring layer through a transparent or translucent thermally conductive adhesive or a solder.

7. The electronic module according to claim 5, wherein the electrical component is mounted on the upper surface of the transparent ceramic layer through a transparent or translucent thermally conductive adhesive.

8. The electronic module according to claim 5, further comprising:

a package material layer covering the transparent ceramic layer, the metal wiring layer, the electrical component and the wires, wherein the electrical component further outputs a third light ray, the third light ray is reflected, by a boundary surface of the package material layer, back to the transparent ceramic layer and transmits through the transparent ceramic layer, and is reflected, by the metal bottom layer, to transmit through the transparent ceramic layer and the package material layer, and then the third light ray is output from the package material layer.

9. The electronic module according to claim 5, further comprising:

a package material layer covering the transparent ceramic layer, the metal wiring layer, the electrical component and the wires, wherein the package material layer comprises a plurality of fluorescent particles.

10. The electronic module according to claim 9, wherein the electrical component further outputs a fourth light ray, each of the fluorescent particles receives the fourth light ray and then generates a fifth light ray, the fifth light ray transmits through the transparent ceramic layer and is then reflected, by the metal wiring layer, to transmit through the transparent ceramic layer and the package material layer, and finally output from the package material layer.

11. A method of manufacturing a fully reflective and highly thermoconductive electronic module, the method comprising the steps of:

grinding and oxidizing a metal bottom layer to make the metal bottom layer have a first reflective surface;

providing a patterned metal wiring layer;

interposing a transparent ceramic layer between the metal wiring layer and the metal bottom layer to form an assembly; and

placing the assembly in a high-temperature environment to make the transparent ceramic layer bond the metal bottom layer and the metal wiring layer together, so that the fully reflective and highly thermoconductive electronic module comprises;

providing the metal bottom layer with the first reflective surface;

bonding a lower surface of the transparent ceramic layer to the first reflective surface of the metal bottom layer; and

disposing the patterned metal wiring layer on an upper surface of the transparent ceramic layer, wherein the first reflective surface reflects a first light ray, transmitting through the transparent ceramic layer, to the upper surface of the transparent ceramic layer, the metal wiring layer has a second reflective surface, the second reflective surface is disposed opposite the first reflective surface, the first reflective surface reflects a second light ray, transmitting through the transparent ceramic layer, to the second reflective surface, and the second reflective surface reflects the second light ray to the first reflective surface, which finally reflects the second light ray to transmit through the transparent ceramic layer.

12. The method according to claim 11, wherein a temperature of the high-temperature environment ranges from 1060°

C. to 1080°

C.

13. The method according to claim 11, further comprising the steps of:

mounting an electrical component onto the transparent ceramic layer; and

providing a plurality of wires to electrically connect the electrical component to the metal wiring layer.

14. The method according to claim 13, further comprising the steps of:

covering the transparent ceramic layer, the metal wiring layer, the electrical component and the wires with a package material layer.

15. The method according to claim 11, wherein the step of providing the metal wiring layer comprises:

grinding and oxidizing the metal wiring layer to form the second reflective surface disposed opposite the first reflective surface.

16. A method of manufacturing a fully reflective and highly thermoconductive electronic module, the method comprising the steps of:

grinding and oxidizing a metal bottom layer to make the metal bottom layer have a first reflective surface;

combining a transparent ceramic layer with the metal bottom layer with a lower surface of the transparent ceramic layer contacting with the first reflective surface of the metal bottom layer to form an assembly;

placing the assembly in a high-temperature environment to bond the transparent ceramic layer to the metal bottom layer; and

forming a patterned metal wiring layer on an upper surface of the transparent ceramic layer, so that the fully reflective and highly thermoconductive electronic module comprises;

providing the metal bottom layer with the first reflective surface;

bonding the lower surface of the transparent ceramic layer to the first reflective surface of the metal bottom layer; and

disposing the patterned metal wiring layer on the upper surface of the transparent ceramic layer, wherein the first reflective surface reflects a first light ray, transmitting through the transparent ceramic layer, to the upper surface of the transparent ceramic layer, the metal wiring layer has a second reflective surface, the second reflective surface is disposed opposite the first reflective surface, the first reflective surface reflects a second light ray, transmitting through the transparent ceramic layer, to the second reflective surface, and the second reflective surface reflects the second light ray to the first reflective surface, which finally reflects the second light ray to transmit through the transparent ceramic layer.