Light-emitting diode with enhanced brightness and method for fabricating the same

• US 6,809,341 B2
• Filed: 03/11/2003
• Issued: 10/26/2004
• Est. Priority Date: 03/12/2002
• Status: Expired due to Term

• Current Assignee: OPTO Tech University
• Original Assignee: OPTO Tech University
• Inventors: Tsai, Chang-Da, Lin, San Bao, Lin, Ming-Der, Hsu, Jung-Kuei, Wang, Kwang-Ru, Lu, Hung-Yuan, Hwang, Yung-Chiang, Yu, Hsueh-Chih, Chang, Chui-Chuan
• Primary Examiner(s): QUACH, TUAN N
• Application Number:
  US10/384,619
• Publication Number:
  US 20040178415A1
• Time in Patent Office: 595 Days
• Field of Search: 257/79, 257/86, 257/91, 257/99
• US Class Current: 257/79
• CPC Class Codes: H01L 21/42 Bombardment with radiation
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/14 with a carrier transport control structure, e.g. highly-doped semiconductor layer or current-blocking structure
• CPC Class Codes: H01L 33/382 the electrode extending partially in or entirely through the semiconductor body
• CPC Class Codes: H01L 33/387 with a plurality of electrode regions in direct contact with the semiconductor body and being electrically interconnected by another electrode layer
• CPC Class Codes: H01L 33/405 Reflective materials

Abstract

A light-emitting diode with enhanced brightness and a method for fabricating the diode is provided. The light-emitting diode includes an epitaxial LED structure having at least one lighting-emitting active layer with a plurality of windows formed in a highly doped layer. At least one conductive contact is formed on the bottom surface of the highly doped layer. A transparent material layer is formed in the windows. An adhesion layer is formed between the transparent material layer and a permanent substrate. A bottom electrode is formed on the bottom surface of the permanent substrate and an opposed electrode is formed on the top surface of the epitaxial LED structure.

Claims

1. A light-emitting diode with enhanced brightness, comprising:

an epitaxial LED structure having at least one light-emitting active layer and a highly doped layer, said highly doped layer having a plurality of windows formed therethrough;

at least one conductive contact formed on a bottom surface of said highly doped layer;

a transparent material layer formed in said windows;

an adhesion layer formed between said transparent material layer and a permanent substrate;

a bottom electrode formed on a bottom surface of said permanent

an opposed electrode formed on a top surface of said epitaxial LED structure.

2. The light-emitting diode of claim 1, further comprising a reflective layer formed between said transparent layer and said adhesion layer.

3. The light-emitting diode of claim 2, wherein said reflective layer and said adhesion layer are formed of a same material composition.

4. The light-emitting diode of claim 1, further comprising a current diffusion layer formed between said epitaxial LED structure and said opposed electrode.

5. The light-emitting diode of claim 1, wherein said adhesion layer is a bottom electrode.

6. The light-emitting diode of claim 1, wherein said transparent material layer is selected from the group of conductive materials consisting of ITO, zinc oxide, tin oxide, indium oxide and combinations thereof.

7. The light-emitting diode of claim 1, wherein said transparent material layer is selected from the group of insulating materials consisting of polymer, quartz, glass and combinations thereof.

8. The light-emitting diode of claim 1, wherein said permanent substrate is formed of a material with good thermal conductivity characteristics.

9. The light-emitting diode of claim 8, wherein said permanent substrate is formed of one of Si, BN, AIN, A1₂O₃, MgO, MgO₂ and combinations thereof.

10. The light-emitting diode of claim 1, wherein said epitaxial LED structure is selected from a vertical LED structure and a planar LED structure.