LED with integral via

• US 7,505,275 B2
• Filed: 03/10/2006
• Issued: 03/17/2009
• Est. Priority Date: 11/04/2005
• Status: Expired due to Fees

• Current Assignee: NeoGraf Solutions, LLC
• Original Assignee: Graftech International Holdings Inc (Graftech International Limited)
• Inventors: Cartiglia, James R., Reis, Bradley E.
• Primary Examiner(s): Gandhi; Jatprakash N
• Assistant Examiner(s): Smith; Courtney L
• Application Number:
  US11/377,662
• Publication Number:
  US 20070139895A1
• Time in Patent Office: 1,103 Days
• Field of Search: 361/710, 361/719, 361/703, 361/707, 361/717, 165/80.3, 165/185, 165/46, 165/172, 257 13- 14, 257/79, 257/99, 174/16.3, 428/195.1, 313/600
• US Class Current: 361/717
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/642 characterized by the shape
• CPC Class Codes: H05K 1/021 Components thermally connected to metal substrates or heat-sinks by insert mounting
• CPC Class Codes: H05K 1/182 associated with components mounted in the printed circuit board, e.g. insert mounted components [IMC]
• CPC Class Codes: H05K 2201/10106 Light emitting diode [LED]

Abstract

A light emitting diode comprising a body and a thermal via integral therewith and which extends from the body.

Claims

1. A circuit assembly comprising a substrate which comprises a dielectric layer, a heat spreader layer which comprises at least one sheet of compressed particles of exfoliated graphite, wherein the heat spreader layer is located at a first surface of the substrate, a light emitting diode and a circuit located at a second surface of the substrate, the light emitting diode comprising a body and a thermal via integral therewith, wherein the thermal via extends from the body through the dielectric layer and further wherein the heat spreader layer has an opening therein into which the thermal via extends such that it is in thermal connection with the heat spreader layer.

2. The circuit assembly of claim 1, wherein the dielectric layer comprises a material selected from the group consisting of glass fiber impregnated with resin;

polytetrafluoroethylene;

expanded polytetrafluoroethylene;

a polymer;

a ceramic material;

or combinations thereof.

3. The circuit assembly of claim 1, wherein the dielectric layer comprises anodized aluminum, aluminum nitride, aluminum oxide or alumina.

4. The circuit assembly of claim 1, wherein the thermal via comprises a high thermal conductivity material.

5. The circuit assembly of claim 4, wherein the thermal conductivity of the thermal via is greater than the through-thickness thermal conductivity of the dielectric layer.

6. The circuit assembly of claim 4, wherein the thermal via comprises copper, aluminum, or alloys thereof.

7. The circuit assembly of claim 1, further comprising a dielectric layer on the thermal via, wherein the dielectric layer comprises anodized aluminum, aluminum nitride, aluminum oxide or alumina.

8. A circuit assembly comprising a substrate comprising a dielectric layer, a light emitting diode and a circuit located at a surface of the substrate, a heat spreader layer which comprises at least one sheet of compressed particles of exfoliated graphite, the heat spreader layer located at a surface of the substrate, wherein the light emitting diode is in thermal connection with the heat spreader layer through a thermal via integral therewith, where the thermal via extends from the light emitting diode through the dielectric layer and further wherein the heat spreader layer has an opening therein into which the thermal via extends.

9. The circuit assembly of claim 8, wherein the dielectric layer is disposed between the heat spreader layer and the circuit.

10. The circuit assembly of claim 8, wherein the dielectric layer comprises a material selected from the group consisting of glass fiber impregnated with resin;

polytetrafluoroethylene;

expanded polytetrafluoroethylene;

a polymer;

a ceramic material;

or combinations thereof.

11. The circuit assembly of claim 8, wherein the dielectric layer comprises anodized aluminum, aluminum nitride, aluminum oxide or alumina.

12. The circuit assembly of claim 8 wherein the thermal via is sized to extend through the dielectric layer.