High efficiency lighting device

• US 7,947,991 B2
• Filed: 07/29/2008
• Issued: 05/24/2011
• Est. Priority Date: 07/29/2008
• Status: Active Grant

• Current Assignee: Epistar Corporation
• Original Assignee: Huga Optotech Incorporated (Epistar Corporation)
• Inventors: Wang, Wei-Kai, Shih, Wen-Chung, Lin, Su-Hui
• Primary Examiner(s): Tran; Long K
• Application Number:
  US12/181,916
• Publication Number:
  US 20100025704A1
• Time in Patent Office: 1,029 Days
• Field of Search: 257/79, 257/98, 257/103, 257/E33.063, 257/E33.069, 257/E51.021
• US Class Current: 257/79
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector

Abstract

A high efficiency lighting device comprising a light emitting diode structure, an eutectic layer and a distributed-Bragg reflecting layer (DBR) therebetween is disclosed. The distributed-Bragg reflecting layer is attached to said light emitting diode structure by vapor deposition and comprises a plurality of high refraction layers, a plurality of low refraction layers and a micro-contact layer array. The high refraction layers and said low refraction layers are arranged in an alternating manner, so as to form a stacked thin film having an alternate high/low refraction pattern. The micro-contact layers are in said stacked thin film and extend vertically through the stacked thin film, therefore connecting said light emitting diode structure and said eutectic layer.

Claims

1. A high efficiency lighting device, comprising:

a light emitting diode structure;

an eutectic layer; and

a distributed-Bragg reflecting layer (DBR) between said light emitting diode structure and said eutectic layer, said distributed-Bragg reflecting layer being attached to said light emitting diode structure by vapor deposition, wherein said distributed-Bragg reflecting layer comprises;

a plurality of high refraction layers;

a plurality of low refraction layers, wherein said high refraction layers and said low refraction layers are arranged in an alternating manner, so as to form a stacked thin film having an alternate high/low refraction pattern; and

a micro-contact layer array in said stacked thin film and including at least one micro-contact layer, wherein said eutectic layer is made of heat dissipation materials and in direct contact with said distributed-Bragg reflecting layer, and wherein said micro-contact layer array extends vertically through the stacked thin film and connects said light emitting diode structure and said eutectic layer.

2. The device of claim 1, wherein said high refraction layers are titanium dioxide layers, and said low refraction layers are silicon dioxide layers.

3. The device of claim 1, wherein said micro-contact layers are formed by using metal materials.

4. The device of claim 1, wherein said eutectic layer is made from gold/tin alloy.

5. The device of claim 1, wherein the thickness of said eutectic layer is around 1.5 micrometers.