LIGHT EMITTING DEVICE HAVING LIGHT EMITTING ELEMENTS

• US 20090108272A1
• Filed: 01/12/2009
• Published: 04/30/2009
• Est. Priority Date: 08/29/2002
• Status: Active Grant

• Current Assignee: Seoul Semiconductor Co., Ltd.
• Original Assignee: Seoul Semiconductor Co., Ltd.
• Inventors: Ao, Jin-Ping, Ono, Yasuo, Sakai, Shiro
• Granted Patent: US 8,097,889 B2
• Time in Patent Office: Days
• US Class Current: 257/88
• CPC Class Codes: H01L 2224/24 of an individual high density interconnect connector
• CPC Class Codes: H01L 27/15 including semiconductor components having potential barriers, specially adapted for light emission
• CPC Class Codes: H01L 27/153 in a repetitive configuration, e.g. LED bars
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

A light-emitting device operating on a high drive voltage and a small drive current. LEDs (1) are two-dimensionally formed on an insulating substrate (10) of e.g., sapphire monolithically and connected in series to form an LED array. Two such LED arrays are connected to electrodes (32) in inverse parallel. Air-bridge wiring (28) is formed between the LEDs (1) and between the LEDs (1) and electrodes (32). The LED arrays are arranged zigzag to form a plurality of LEDs (1) to produce a high drive voltage and a small drive current. Two LED arrays are connected in inverse parallel, and therefore an AC power supply can be used as the power supply.

Claims

1. A light emitting device, comprising:

a single insulating substrate;

at least a first array of GaN-based light emitting elements connected in series and disposed on the single insulating substrate,

wherein the first array of light emitting elements form a current path comprising a first part, a second part, and a third part, the first part extending from a first side of the substrate to a second side of the substrate, the second part extending along the second side of the substrate, and the third part extending from the second side of the substrate to the first side of the substrate.

2. The light emitting device of claim 1, wherein the current path further comprises a fourth part and a fifth part, the fourth part extending along the first side of the substrate, and the fifth part extending from the first side of the substrate to the second side of the substrate.

3. The light emitting device of claim 2, further comprising a first electrode and a second electrode, the first electrode being disposed at a first distal end of the current path and the second electrode being disposed at a second distal end of the current path.

4. The light emitting device according to claim 3 wherein each of the light emitting elements and electrodes has a substantially square planar shape.

5. The light emitting device according to claim 3 wherein each of the light emitting elements and electrodes has a substantially triangular planar shape.

6. The light emitting device according to claim 1 wherein the light emitting elements are connected by air bridge lines.

7. The light emitting device according to claim 3 wherein at least one of the first and second electrodes is an electrode for an alternate power supply

8. The light emitting device according to claim 1 wherein the light emitting elements are separated electrically by sapphire which is used as the substrate.

9. The light-emitting device according to claim 1 further comprising a second array of Ga—

N based light-emitting elements connected in series wherein the second array of light-emitting elements is connected in inverse parallel with the first array of light-emitting elements.

10. A light emitting device comprising:

a single substrate;

a first array of light-emitting elements connected in series on the substrate;

a second array of light-emitting elements connected in series on the substrate, wherein the first array forms a first current path and the second array forms a second current path wherein said first and second paths are arranged in a pattern.

11. The light-emitting device according to claim 10 wherein each of the light emitting elements and electrodes has a substantially square shape.

12. The light-emitting device according to claim 10 wherein each of the light emitting elements and electrodes has a substantially triangular shape.

13. The light-emitting device according to claim 10 wherein the first array and second array are connected in inverse parallel between two electrodes.