Light-emitting diode

• US 8,134,174 B2
• Filed: 03/11/2010
• Issued: 03/13/2012
• Est. Priority Date: 10/02/2009
• Status: Expired due to Fees

• Current Assignee: Chi Mei Lighting Technology Corp. (CHI MEI Corporation)
• Original Assignee: CHI MEI Lighting Technology Group
• Inventors: Yu, Kuohui, Wang, Chienchun, Chu, Changhsin, Li, Menghsin
• Primary Examiner(s): Landau, Matthew
• Assistant Examiner(s): Malek, Maliheh
• Application Number:
  US12/721,923
• Publication Number:
  US 20110079805A1
• Time in Patent Office: 733 Days
• Field of Search: 257/9, 257 11- 14, 257/23, 257/37, 257/79, 257/86, 257/88, 257/90, 257/91, 257 94-100, 257/183, 257/200, 257/594, 257/684, 257/688, 257/E33.001, 257/E33.002, 257E33005-E33007, 257E33055-E33059, 257/E33.061, 257/E33.062, 257E33066-E33073, 257/E25.028, 438 26- 27, 438 29- 32, 438 38- 43, 438 46- 47
• US Class Current: 257/99
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/382 the electrode extending partially in or entirely through the semiconductor body
• CPC Class Codes: H01L 33/54 having a particular shape

Abstract

A light-emitting diode and a method for manufacturing the same are described. The light-emitting diode includes a bonding substrate, a first conductivity type electrode, a bonding layer, an epitaxial structure, a second conductivity type electrode, a growth substrate and an encapsulant layer. The first conductivity type electrode and the bonding layer are respectively disposed on two surfaces of the bonding substrate. The epitaxial structure includes a first conductivity type semiconductor layer, an active layer and a second conductivity type semiconductor layer. A trench is set around the epitaxial structure and extends from the second conductivity type semiconductor layer to the first conductivity type semiconductor layer. The second conductivity type electrode is electrically connected to the second conductivity type semiconductor layer. The growth substrate is disposed on the epitaxial structure and includes a cavity exposing the epitaxial structure and the trench. The encapsulant layer is filled in the cavity.

Claims

1. A light-emitting diode, comprising:

a bonding substrate comprising a first surface and a second surface on opposite sides;

a first conductivity type electrode disposed on the second surface of the bonding substrate;

a bonding layer disposed on the first surface of the bonding substrate;

an epitaxial structure including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer stacked on the bonding layer in sequence, wherein the first conductivity type semiconductor layer and the second conductivity type semiconductor layer have different conductivity types, and a trench is set around the epitaxial structure and extends from the second conductivity type semiconductor layer to the first conductivity type semiconductor layer;

a second conductivity type electrode electrically connected to the second conductivity type semiconductor layer; and

a growth substrate disposed on the epitaxial structure, wherein the growth substrate comprises a cavity exposing a portion of the epitaxial structure and the trench.

2. The light-emitting diode according to claim 1, wherein the bonding substrate comprises Si, Al, Cu, Mo, Ni, CuW, or a combination thereof.

3. The light-emitting diode according to claim 1, wherein the first conductivity type electrode comprises a eutectic metal or a noneutectic metal, and wherein the eutectic metal comprises AuSn, AgSn, AgSnCu, AuSnCu, AuBe, or a combination thereof, and the noneutectic metal comprises Au, Pt, Cr, Ti, Ni, Al, or a combination thereof.

4. The light-emitting diode according to claim 1, further comprising a first conductivity type contact layer between the bonding layer and the first conductivity type semiconductor layer.

5. The light-emitting diode according to claim 4, wherein the first conductivity type contact layer comprises a Ni/Au structure, a Ni/Ag structure, an ITO layer, a ZnO layer, a GZO layer, an AZO layer or an InO₂ layer.

6. The light-emitting diode according to claim 4, further comprising the first conductivity type contact layer between a reflective layer and the first conductivity type semiconductor layer.

7. The light-emitting diode according to claim 1, wherein the epitaxial structure is made of a material comprising an InAlGaN-based material or an InAlGaP-based material.

8. The light-emitting diode according to claim 1, wherein the epitaxial structure further comprises:

an undoped semiconductor layer disposed on the second conductivity type semiconductor layer; and

a buffer layer disposed between the growth substrate and the undoped semiconductor layer.

9. The light-emitting diode according to claim 1, wherein the second conductivity type electrode is disposed on the second conductivity type semiconductor layer, and the cavity exposes the second conductivity type electrode.

10. The light-emitting diode according to claim 9, further comprising a protection layer, wherein the protection layer covers a portion of the second conductivity type electrode, the exposed portion of the epitaxial structure, and a side surface and a bottom surface of the trench.

11. The light-emitting diode according to claim 1, further comprising a contact hole, wherein the contact hole extends from the first conductivity type semiconductor layer to the second conductivity type semiconductor layer, and wherein the contact hole exposes a portion of the second conductivity type semiconductor layer.

12. The light-emitting diode according to claim 11, wherein the second conductivity type electrode is disposed on the portion of the second conductivity type semiconductor layer.

13. The light-emitting diode according to claim 12, further comprising:

an insulation layer covering a portion of the second conductivity type electrode and a bottom surface and a side surface of the contact hole; and

a second conductivity type metal electrode layer filling up the contact hole.

14. The light-emitting diode according to claim 13, further comprising a protection layer, wherein the protection layer covers the exposed portion of the epitaxial structure, and a side surface and a bottom surface of the trench.

15. The light-emitting diode according to claim 14, further comprising an optical structure disposed on the portion of the epitaxial structure, wherein the optical structure is a part of the growth substrate.

16. The light-emitting diode according to claim 11, wherein a depth of the contact hole is between about 10 μ

m and about 400 μ

m.

17. The light-emitting diode according to claim 1, wherein the growth substrate comprises Al₂O₃, SiC, or GaAs.

18. The light-emitting diode according to claim 1, wherein the growth substrate comprises a sidewall, and wherein a thickness of the sidewall of the growth substrate is between about 1 μ

m and about 200 μ

m.

19. The light-emitting diode according to claim 1, wherein the growth substrate comprises a sidewall, and wherein the light-emitting diode further comprises a reflective layer extending on the sidewall and a side surface of the trench.

20. The light-emitting diode according to claim 1, further comprising

a spectrum-converted material layer or a light-scattering material layer covering the exposed portion of the epitaxial structure;

and

an encapsulant layer disposed in the cavity.