Semiconductor light emitting diodes having multiple bond pads and current spreading structures

• US 9,362,455 B2
• Filed: 02/24/2011
• Issued: 06/07/2016
• Est. Priority Date: 02/24/2011
• Status: Active Grant

• Current Assignee: CREE Led Incorporated (Smart Global Holdings Incorporated)
• Original Assignee: CREE Incorporated (Wolfspeed, Inc.)
• Inventors: Edmond, John Adam, Donofrlo, Matthew, Pyles, Shawn
• Primary Examiner(s): Mondt, Johannes P
• Application Number:
  US13/034,267
• Publication Number:
  US 20120217530A1
• Time in Patent Office: 1,930 Days
• US Class Current: 1/1
• 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 33/38 with a particular shape
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• 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

A light emitting device includes a diode region comprising a first face and opposing edges, and a bond pad structure comprising at least three bond pads along only one of the opposing edges of the first face.

Claims

1. A light emitting device comprising:

a diode region comprising a first face and opposing edges; and

a bond pad structure comprising at least three bond pads along only one of the opposing edges of the first face without bond pads on any other opposing edges, wherein each of the at least three bond pads of the bond pad structure forms an ohmic contact with a common, electrically continuous n- or p-layer of the diode region,

wherein the bond pad structure comprises current spreading fingers extending from the at least three bond pads, and at least two bond pad unit cells arranged in a row along the first face of the diode region, each bond pad unit cell comprising a bond pad and at least two of the current spreading fingers, and each of the bond pad unit cells comprises a different pattern of current spreading fingers.

2. The light emitting device of claim 1, wherein at least one of the plurality of bond pad unit cells comprises a pattern of current spreading fingers that represents information.

3. The light emitting device of claim 2, wherein the pattern of current spreading fingers that represents information is arranged to form alphanumeric characters and the current spreading fingers comprise metal.

4. The light emitting device of claim 3, wherein the pattern of current spreading fingers is arranged to form alphanumeric characters that communicate information relating to an operating property of the light emitting diode.

5. The light emitting device of claim 3, wherein the pattern of current spreading fingers are arranged to form alphanumeric characters that communicate information relating to the color temperature, wavelength, and/or luminous intensity of light emitted by the light emitting diode.

6. The light emitting device of claim 1, wherein each of the bond pads is configured to receive a wire bond structure.

7. The light emitting device of claim 1, wherein the diode region comprises a second face opposite the first face, and the opposing edges comprise first and second opposing edges running along a width of the first face of the diode region, and the first face further comprises third and fourth opposing edges running along a length of the first face of the diode region, wherein the at least three bond pads are spaced apart along the first face from the third edge to the fourth edge of the first face and offset towards the first edge of the first face of the diode region.

8. The light emitting device of claim 7, wherein a ratio of the width of the first face to the length of the first face is greater than one.

9. The light emitting device of claim 7, wherein the current spreading bond pad structure comprises at least five bond pads spaced apart along the first face from the third edge to the fourth edge of the first face.

10. The light emitting device of claim 7, wherein the current spreading bond pad structure comprises at least eight bond pads spaced apart along the first face from the third edge to the fourth edge of the first face.

11. The light emitting device of claim 1, wherein the current spreading fingers are curved.

17. The light emitting device of claim 1, wherein a length of the diode region is greater than a width of the diode region, and the at least three bond pads are along the length of the diode region.

18. The light emitting device of claim 1, wherein the bond pad structure forms an ohmic contact with a cathode or anode of the diode region.

19. The light emitting device of claim 8, wherein the at least three bond pads comprise a single row along the first face from the third edge to the fourth edge.

21. The light emitting device of claim 1, wherein the at least three bond pads are electrically continuous.

12. A light emitting device comprising:

a semiconductor region comprising a first face; and

a contact pattern arranged on the first face to convey information, wherein the contact pattern comprises metal that forms current spreading fingers, at least some of the current spreading fingers being electrically interconnected to others of the current spreading fingers and being arranged to form alphanumeric characters, wherein the alphanumeric characters of the contact pattern form an ohmic contact with a common, electrically continuous layer of the semiconductor region, wherein the bond pad structure comprises at least two bond pad unit cells arranged in a row along the first face of the semiconductor region, each bond pad unit cell comprising a bond pad and at least two of the current spreading fingers, and each of the bond pad unit cells comprises a different pattern of current spreading fingers, each of the different patterns of current spreading fingers forming the alphanumeric characters.

13. The light emitting device of claim 12, wherein the alphanumeric characters form communicate information relating to an operating property of the light emitting device.

14. The light emitting device of claim 12, wherein the alphanumeric characters form communicate information relating to the color temperature, wavelength, and/or luminous intensity of light emitted by the light emitting device.

15. The light emitting device of claim 12, wherein the current spreading fingers are curved.

16. A light emitting device comprising:

a diode region comprising a first face and opposing edges and a second face opposite the first face, and the opposing edges comprise first and second opposing edges running along a width of the first face of the diode region, and the first face further comprises third and fourth opposing edges running along a length of the first face of the diode region; and

a bond pad structure comprising at least four bond pads along only one of the opposing edges of the first face without bond pads on any other opposing edges, wherein the at least four bond pads are spaced apart along the first face from the third edge to the fourth edge of the first face and offset towards the first edge of the first face of the diode region, and wherein the bond pad structure further comprises current spreading fingers extending from the at least four bond pads onto the diode region and a ratio of the width of the first face to the length of the first face is greater than one, wherein the at least four bond pads of the bond pad structure form an ohmic contact with a common, electrically continuous n- or p-layer of the diode region, wherein the bond pad structure comprises at least two bond pad unit cells arranged in a row along the first face of the diode region, each bond pad unit cell comprising one of the at least four bond pads and at least two of the current spreading fingers, and each of the bond pad unit cells comprises a different pattern of current spreading fingers.

20. The light emitting device of claim 16, wherein the at least four bond pads comprise a single row along the first face from the third edge to the fourth edge.

22. The light emitting device of claim 16, wherein the at least four bond pads are electrically continuous.