Ac Light Emitting Diode and Method for Fabricating the Same

• US 20080191222A1
• Filed: 08/01/2006
• Published: 08/14/2008
• Est. Priority Date: 08/09/2005
• Status: Active Grant

• Current Assignee: Seoul Viosys Co., Ltd. (Seoul Semiconductor Co., Ltd.)
• Original Assignee: Seoul Optodevice Company Limited (Seoul Semiconductor Co., Ltd.)
• Inventors: Lee, Jae Ho
• Granted Patent: US 8,901,575 B2
• Time in Patent Office: Days
• US Class Current: 257/91
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• 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 33/58 Optical field-shaping elements
• 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

The present invention relates to an AC light emitting diode. An object of the present invention is to provide an AC light emitting diode wherein various designs for enhancement of the intensity of light, prevention of flickering of light or the like become possible, while coming out of a unified method of always using only one metal wire with respect to one electrode when electrodes of adjacent light emitting cells are connected through metal wires. To this end, the present invention provides an AC light emitting diode comprising a substrate; bonding pads positioned on the substrate; a plurality of light emitting cells arranged in a matrix form on the substrate; and a wiring means electrically connecting the bonding pads and the plurality of light emitting cells, wherein the wiring means includes a plurality of metal wires connecting an electrode of one of the light emitting cells with electrodes of other electrodes adjacent to the one of the light emitting cells.

Claims

1. An AC light emitting diode comprising:

a substrate;

bonding pads positioned on the substrate;

a plurality of light emitting cells arranged in a matrix form on the substrate; and

a wiring means electrically connecting the bonding pads and the plurality of light emitting cells,

wherein the wiring means includes a plurality of metal wires connecting an electrode of one of the light emitting cells with electrodes of other light emitting cells adjacent to the one of the light emitting cells.

2. The AC light emitting diode as claimed in claim 1, wherein the plurality of metal wires connect a P-type electrode of one of the light emitting cells with electrodes of other light emitting cells adjacent to the one of the light emitting cells.

3. The AC light emitting diode as claimed in claim 1, wherein the plurality of metal wires connect an N-type electrode of one of the light emitting cells with electrodes of other light emitting cells adjacent to the one of the light emitting cells.

4. The AC light emitting diode as claimed in claim 1, wherein the bonding pads are arranged together with the plurality of light emitting cells as elements of the matrix.

5. The AC light emitting diode as claimed in claim 1, wherein each of the plurality of light emitting cells has first and second electrodes of a P-type and an N-type, a light emitting cell adjacent to two light emitting cells among the plurality of light emitting cells has a first electrode connected to a second electrode of one of the adjacent two light emitting cells through a metal wire, and a second electrode connected to a first electrode of the other of the adjacent two light emitting cells through another metal wire.

6. The AC light emitting diode as claimed in claim 4, wherein each of the plurality of light emitting cells has first and second electrodes of a P-type and an N-type, a light emitting cell adjacent to two elements of the matrix having the elements of which are the light emitting cells or bonding pad has a first electrode connected to a second electrode of an adjacent light emitting cell or the bonding pad through a metal wire, and a second electrode connected to a first electrode of another adjacent light emitting cell or the bonding pad through another metal wire.

7. The AC light emitting diode as claimed in claim 1, wherein each of the plurality of light emitting cells has first and second electrodes of a P-type and an N-type, a light emitting cell adjacent to three light emitting cells among the plurality of light emitting cells has a first electrode connected to a second electrode of one of the adjacent three light emitting cells through a metal wire, and a second electrode connected to first electrodes of the others of the adjacent three light emitting cells through other two metal wires.

8. The AC light emitting diode as claimed in claim 4, wherein each of the plurality of light emitting cells has first and second electrodes of a P-type and an N-type, a light emitting cell adjacent to a bonding pad and two light emitting cells among the plurality of light emitting cells has a first electrode connected to a second electrode of one of the adjacent two light emitting cells through a metal wire, and a second electrode connected to a first electrode of the other of the adjacent two light emitting cells and the adjacent bonding pad through other two metal wires.

9. The AC light emitting diode as claimed in claim 1, wherein each of the plurality of light emitting cells has first and second electrodes of a P-type and an N-type, a light emitting cell adjacent to four light emitting cells among the plurality of light emitting cells has a first electrode connected to first electrodes of two of the adjacent four light emitting cells through two metal wires, and a second electrode connected to second electrodes of the others of the adjacent four light emitting cells through other two metal wires.

10. The AC light emitting diode as claimed in claim 4, wherein each of the plurality of light emitting cells has first and second electrodes of a P-type and an N-type, a light emitting cell adjacent to a bonding pad and three light emitting cells among the plurality of light emitting cells has a first electrode connected to second electrodes of two of the adjacent three light emitting cells through two metal wires, and a second electrode connected to a first electrode of the other of the adjacent three light emitting cells and the bonding pad through other two metal wires.

11. The AC light emitting diode as claimed in claim 1, further comprising light guide means formed as an element of the matrix to focus light emitted from the plurality of light emitting cells adjacent to the light guide means and to radiate the light to the outside.

12. The AC light emitting diode as claimed in claim 11, wherein the light guide means consist of a plurality of light guide portions regularly arranged at a predetermined interval.

13. The AC light emitting diode as claimed in claim 1, wherein the plurality of metal wires are formed through air-bridge or step-cover process.

14. The AC light emitting diode as claimed in claim 1, wherein the plurality of light emitting cells include at least a pair of arrays of first and second arrays, and the plurality of metal wires comprise a metal wire connecting the same kinds of electrodes of adjacent two of the light emitting cells provided in the same first or second array and a metal wire connecting first and second electrodes of adjacent two of the light emitting cells respectively provided in the first and second arrays.

15. The AC light emitting diode as claimed in claim 14, wherein the bonding pads are respectively arranged near both ends of the pair of arrays and electrically connected to the light emitting cells provided at both the ends of the pair of arrays through some of the plurality of metal wires.

16. The AC light emitting diode as claimed in claim 15, wherein two facing electrodes of adjacent two of the light emitting cells in the same array are the same as the first or second electrode.

17. The AC light emitting diode as claimed in claim 16, wherein two facing electrodes of adjacent two of the light emitting cells provided in the first and second arrays, respectively, are first and second electrodes different from each other.

18. A method of fabricating an AC light emitting diode, comprising the steps of:

preparing a substrate;

forming bonding pads and a plurality of light emitting cells on the substrate, the plurality of light emitting cells being arranged in a matrix form; and

electrically connecting the bonding pads and the plurality of light emitting cells through a plurality of metal wires, the plurality of metal wires comprising at least two metal wires connecting an electrode of one of the light emitting cells and electrodes of others of the light emitting cells adjacent to the one of the light emitting cells.

19. The method as claimed in claim 18, further comprising at least one light guide portion further formed as an element of the matrix to focus light emitted from the plurality of light emitting cells adjacent to the at least light guide portion and to radiate the light to the outside.

20. The method as claimed in claim 19, wherein a plurality of light guide portions are formed to be regularly arranged at a predetermined interval.

21. The method as claimed in claim 18, wherein the plurality of metal wires are formed through air-bridge or step-cover process.

22. The method as claimed in claim 18, wherein the plurality of light emitting cells are formed to constitute at least one pair of arrays of first and second arrays, and the plurality of light emitting cells are electrically connected through a first metal wire connecting the same kinds of electrodes of adjacent two of the light emitting cells provided in each of the first and second arrays and through metal wires connecting first and second electrodes of adjacent two of the light emitting cells respectively provided in the first and second arrays.

23. The method as claimed in claim 22, wherein the bonding pads are formed to be respectively arranged near both ends of the pair of arrays, and the bonding pads and the light emitting cells provided at both the ends of the pair of arrays are connected through different metal wires.

24. The method as claimed in claim 22, wherein adjacent two of the light emitting cells provided in the same array are arranged so that the same kinds of electrodes face each other.

25. The method as claimed in claim 24, wherein adjacent two of the light emitting cells respectively provided in the first and second arrays are arranged so that different kinds of electrodes face each other.