Light emitting device

• US 9,437,784 B2
• Filed: 03/15/2013
• Issued: 09/06/2016
• Est. Priority Date: 10/29/2012
• Status: Active Grant

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Lee, Gun Kyo
• Primary Examiner(s): Such, Matthew W
• Assistant Examiner(s): Smith, Stephen C
• Application Number:
  US13/841,271
• Publication Number:
  US 20140117389A1
• Time in Patent Office: 1,271 Days
• Field of Search: 257/81
• US Class Current: 1/1
• CPC Class Codes: F21K 9/23 Retrofit light sources for lighting devices with a single fitting for each light source, e.g. for substitution of incandescent lamps with bayonet or threaded fittings
• CPC Class Codes: F21V 29/77 with essentially identical diverging planar fins or blades, e.g. with fan-like or star-like cross-section
• CPC Class Codes: F21V 29/83 the elements having apertures, ducts or channels, e.g. heat radiation holes
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/12032 Schottky diode
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• 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

Disclosed is a light emitting device including a light emitting structure comprising a first semiconductor layer, an active layer and a second semiconductor layer, a phosphor plate disposed on the second semiconductor layer, a first electrode portion disposed on the phosphor plate, and a plurality of bonding portions disposed between the light emitting structure and the phosphor plate, the bonding portions bonding the phosphor plate to the light emitting structure, wherein each bonding portion includes at least one first bonding portion electrically connected to the first electrode portion.

Claims

1. A light emitting device comprising:

a light emitting structure comprising a first semiconductor layer, an active layer and a second semiconductor layer;

a pad disposed on the second semiconductor layer;

an extension electrode extending from the pad and disposed on the second semiconductor layer;

a phosphor plate disposed on the second semiconductor layer;

a first electrode disposed on the phosphor plate;

at least one first bonding portion disposed between a portion of the first electrode passing through the phosphor plate and the second semiconductor layer; and

at least one second bonding portion disposed between a lower surface of the phosphor plate and an upper surface of the extension electrode,

wherein the at least one first bonding portion contacts the portion of the first electrode passing through the phosphor plate, and

wherein an upper surface of the at least one second bonding portion contacts only the lower surface of the phosphor plate and is spaced from the first electrode.

2. The light emitting device according to claim 1, wherein the first electrode comprises:

a pad portion disposed on an upper surface of the phosphor plate; and

a connection portion passing through the phosphor plate and connecting the pad portion to the first bonding portion, and

wherein the at least one second bonding portion is spaced from the connection portion.

3. The light emitting device according to claim 2, wherein the second bonding portion comprises:

a first bonding layer disposed on the lower surface of the phosphor plate; and

a second bonding layer disposed on the light emitting structure and bonded to the first bonding layer.

4. The light emitting device according to claim 2, wherein the first bonding portion comprises:

a first bonding electrode disposed on the second semiconductor layer; and

a second bonding electrode disposed on the lower surface of the phosphor plate and on the connection portion, and bonded to the first bonding electrode.

5. The light emitting device according to claim 4, wherein the second bonding electrode is fused to the first bonding electrode.

6. The light emitting device according to claim 5, wherein a fused interface is present between the first bonding electrode and the second bonding electrode.

7. The light emitting device according to claim 4, wherein a melting point of the second bonding electrode is different from a melting point of the first bonding electrode.

8. The light emitting device according to claim 2, wherein the first electrode further comprises an extension electrode disposed on the second semiconductor layer, and

wherein the first bonding portion comprises a third bonding electrode disposed between the connection portion and the extension electrode, and bonds the connection portion to the extension electrode.

9. The light emitting device according to claim 8, wherein a melting point of the third bonding electrode is different from a melting point of the extension electrode.

10. The light emitting device according to claim 9, wherein the third bonding electrode is fused to the extension electrode.

11. The light emitting device according to claim 10, wherein a fused interface is present between the third bonding electrode and the extension electrode.

12. The light emitting device according to claim 8, wherein a width of one portion of the extension electrode bonded to the third bonding electrode is different from a width of another portion of the extension electrode.

13. The light emitting device according to claim 8, wherein a width of the third bonding electrode is smaller than or equivalent to width of the extension electrode.

14. The light emitting device according to claim 1, wherein an air void (gap) is present between the phosphor plate and the light emitting structure.

15. The light emitting device according to claim 2, wherein the first electrode further comprises an extension electrode disposed on the second semiconductor layer,

wherein the first bonding portion comprises a third bonding electrode being disposed between a lower surface of the phosphor plate and the extension electrode and bonding the phosphor plate to the extension electrode, and

wherein the third bonding electrode is arranged in the extension electrode.

16. The light emitting device according to claim 15, wherein the first bonding portion further comprises a bonding electrode being disposed between the connection portion and the extension electrode and bonding the connection portion to the extension electrode.

17. The light emitting device according to claim 4, wherein the first bonding electrode and the second bonding electrode comprise at least one identical metal.

18. The light emitting device according to claim 2, wherein the pad portion is disposed at a side of the phosphor plate.

19. A light emitting device package comprising:

a package body;

a first lead frame and a second lead frame disposed on the package body;

a light emitting device disposed on the second lead frame; and

a resin layer surrounding the light emitting device,

wherein the light emitting device comprises;

a light emitting structure comprising a first semiconductor layer, an active layer and a second semiconductor layer;

a pad disposed on the second semiconductor layer;

an extension electrode extending from the pad and disposed on the second semiconductor layer;

a phosphor plate disposed on the second semiconductor layer;

a first electrode disposed on the phosphor plate;

at least one first bonding portion disposed between a portion of the first electrode passing through the phosphor plate and the second semiconductor layer; and

at least one second bonding portion disposed between a lower surface of the phosphor plate and an upper surface of the extension electrode,

wherein the at least one first bonding portion contacts the portion of the first electrode passing through the phosphor plate, and

wherein an upper surface of the at least one second bonding portion contacts only the lower surface of the phosphor plate and is spaced from the first electrode.