Diode having vertical structure

• US 10,326,055 B2
• Filed: 06/29/2018
• Issued: 06/18/2019
• Est. Priority Date: 10/26/2001
• Status: Expired due to Term

• Current Assignee: Suzhou Lekin Semiconductor Company Limited
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Yoo, Myung Cheol
• Primary Examiner(s): Tran, Minh Loan
• Application Number:
  US16/024,112
• Publication Number:
  US 20180331259A1
• Time in Patent Office: 354 Days
• Field of Search: None
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01L 33/0093 Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector
• CPC Class Codes: H01L 33/12 with a stress relaxation structure, e.g. buffer layer
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/325 characterised by the doping materials
• CPC Class Codes: H01L 33/405 Reflective materials
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• 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
• CPC Class Codes: H01S 5/3013 AIIIBV compounds

Abstract

A light emitting device includes a first conductive-type layer, an active layer, and a second conductive-type layer; a first electrode on a first surface of the first conductive-type layer, the first electrode having a multilayer structure including Pt; a first pad on the first electrode, the first pad disposed on an edge of the first surface of the first conductive-type layer in a cross-sectional view; and a second electrode and a second pad on a second surface of the second conductive-type layer, the second electrode having a metal layer including Ti. In addition, the first pad include Au, further the second electrode is unitary with the second pad, and also the second electrode includes a reflective layer configured to reflect light from the active layer.

Claims

1. A light emitting device, comprising:

a first conductive-type layer, an active layer, and a second conductive-type layer;

a first electrode on a first surface of the first conductive-type layer, the first electrode having a multilayer structure including Pt;

a first pad on the first electrode, the first pad disposed on an edge of the first surface of the first conductive-type layer in a cross-sectional view; and

a second electrode and a second pad on a second surface of the second conductive-type layer, the second electrode having a metal layer including Ti,

wherein the first pad include Au,

wherein the second electrode is unitary with the second pad, and

wherein the second electrode includes a reflective layer configured to reflect light from the active layer.

2. The light emitting device according to claim 1, wherein the first electrode is overlapped with the second electrode and the second pad in a thickness direction of the semiconductor layer.

3. The light emitting device according to claim 1, further comprising a buffer layer disposed between the second electrode and the second surface of the second conductive-type layer.

4. The light emitting device according to claim 1, wherein the second electrode directly contacts the second surface of the second conductive-type layer.

5. The light emitting device according to claim 1, wherein the first surface is opposite the second surface with respect to the active layer.

6. The light emitting device according to claim 1, further comprising a cladding layer disposed between the active layer and the first conductive-type layer.

7. The light emitting device according to claim 6, wherein the cladding layer comprises AlGaN.

8. The light emitting device according to claim 1, wherein a width of the first pad is smaller than a width of the second pad.

9. The light emitting device according to claim 1, wherein the metal layer of the second electrode further comprises Au.

10. The light emitting device according to claim 1, wherein the active layer comprises a multiple quantum well (MQW) layer on the second conductive-type layer.

11. The light emitting device according to claim 1, wherein each of the first conductive-type layer and the second conductive-type layer includes a gallium-nitride based semiconductor layer.

12. The light emitting device according to claim 1, wherein the first conductive-type layer is doped with magnesium with a doping concentration of 10¹⁷ cm⁻

3 or greater.

13. The light emitting device according to claim 1, wherein the second conductive-type layer is doped with silicon with a doping concentration of 10¹⁷ cm⁻

3 or greater.

14. The light emitting device according to claim 1, wherein the active layer includes indium having a composition of 22% to 40%.

15. The light emitting device according to claim 1, wherein the first pad has a thickness of 0.5 μ

m or higher.

16. The light emitting device according to claim 1, wherein the metal layer is disposed at a bottom of the light emitting device.

17. The light emitting device according to claim 1, wherein the first conductive-type is p-type and the second conductive-type is n-type.

18. The light emitting device according to claim 1, further comprising an undoped gallium-nitride layer on the reflective layer.

19. The light emitting device according to claim 1, further comprising a transparent conductive layer on the first conductive-type semiconductor layer, the transparent conductive layer comprising indium-tin-oxide (ITO).

20. The light emitting device according to claim 1, wherein the reflective layer includes Al.