Semiconductor light emitting device

Patent metadata

Field	Value
Publication number	US-2016072004-A1
Application number	US-201514714117-A
Country	US
Kind code	A1
Filing date	May 15, 2015
Priority date	Sep 5, 2014
Publication date	Mar 10, 2016
Grant date	—

Abstract

A semiconductor light emitting device includes: a light emitting structure including a first conductivity-type semiconductor layer, a second conductivity-type semiconductor layer, and an active layer disposed therebetween; a first electrode disposed on the light emitting structure to be electrically connected to the first conductivity-type semiconductor layer; and a second electrode disposed on the light emitting structure to be electrically connected to the second conductivity-type semiconductor layer. The second electrode includes a first layer disposed on the second conductivity-type semiconductor layer, and a second layer disposed on the first layer, having a sheet resistance higher than that of the first layer, and having a thickness less than that of the first layer.

First claim

1 . A semiconductor light emitting device, the device comprising:
a light emitting structure including a first conductivity-type semiconductor layer, a second conductivity-type semiconductor layer, and an active layer disposed therebetween; a first electrode disposed on the light emitting structure to be electrically connected to the first conductivity-type semiconductor layer; and a second electrode disposed on the light emitting structure to be electrically connected to the second conductivity-type semiconductor layer, wherein the second electrode includes a first layer disposed on the second conductivity-type semiconductor layer, and a second layer disposed on the first layer, having a sheet resistance higher than that of the first layer, and having a thickness less than that of the first layer, and a resistivity of a material included in the second layer is greater than a resistivity of a material included in the first layer.

2 . The device of claim 1 , wherein the second layer has an area smaller than that of the first layer.

3 . The device of claim 1 , wherein currents applied to the light emitting structure through the first electrode and the second electrode flow at an interface between the first layer and the second layer in a direction parallel to the interface between the first layer and the second layer.

4 . The device of claim 1 , wherein the first layer is a reflective electrode in ohmic contact with the second conductivity-type semiconductor layer.

5 . The device of claim 1 , wherein the first layer includes silver (Ag).

6 . The device of claim 5 , wherein the second layer includes at least one of chromium (Cr), indium tin oxide (ITO), titanium (Ti), tungsten (W), titanium-tungsten —(TiW), platinum (Pt), and zinc oxide (ZnO).

7 . The device of claim 1 , wherein the thickness of the second layer is less than a half of a thickness of the first layer.

8 . The device of claim 1 , wherein the thickness of the second layer is less than 1,000 angstrom (Å).

9 . The device of claim 1 , wherein the first electrode is electrically connected to the first conductivity-type semiconductor layer through at least one contact hole.

10 . The device of claim 1 , wherein the first conductivity-type semiconductor layer includes a plurality of nanocores, and the active layer and the second conductivity-type semiconductor layer are sequentially disposed on the plurality of nanocores.

11 . The device of claim 1 , wherein the second electrode includes a third layer disposed on the second layer and including an Ag-palladium (Pd)-copper (Cu) alloy.

12 . A semiconductor light emitting device, the device comprising:
a light emitting structure including a first conductivity-type semiconductor layer, an active layer, and a second conductivity-type semiconductor layer sequentially laminated therein; a first electrode disposed on the light emitting structure to be electrically connected to the first conductivity-type semiconductor layer; and a second electrode disposed on the light emitting structure to be electrically connected to the second conductivity-type semiconductor layer, wherein the second electrode includes a first layer disposed on the second conductivity-type semiconductor layer, and a second layer disposed on the first layer, having an area smaller than that of the first layer, and having a sheet resistance higher than that of the first layer, and a resistivity of a material included in the second layer is greater than a resistivity of a material included in the first layer.

13 . The device of claim 12 , wherein the second layer has a thickness less than that of the first layer.

14 . The device of claim 13 , wherein the thickness of the second layer is a half of a thickness of the first layer.

15 . The device of claim 12 , wherein currents applied to the light emitting structure through the first electrode and the second electrode flow at an interface between the first layer and the second layer in a direction parallel to the interface between the first layer and the second layer.

16 . A semiconductor light emitting device, the device comprising:
a light emitting structure including a first conductivity-type semiconductor layer, a second conductivity-type semiconductor layer, and an active layer disposed therebetween; a first electrode electrically connected to the first conductivity-type semiconductor layer; and a second electrode including first and second layers and electrically connected to the second conductivity-type semiconductor layer, wherein the first layer of the second electrode is interposed between the second layer of the second electrode and the second conductivity-type semiconductor layer, and a sheet resistance of the second layer is greater than that of the first layer, and a resistivity of a material included in the second layer is greater than a resistivity of a material included in the first layer.

17 . The device of claim 16 , wherein a thickness of the second layer is less than a thickness of the first layer.

18 . The device of claim 17 , wherein the thickness of the second layer is less than a half of the thickness of the first layer.

19 . The device of claim 17 , wherein the thickness of the second layer is less than 1,000 angstrom (Å).

20 . The device of claim 16 , wherein the second layer has an area less than that of the first layer.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Song Sang Yeob
• Yoon Ju Heon
• Kim Gi Bum
• Kim Hyun Young
• Ha Jong Hoon

Classifications

• H10H20/832 Primary

  characterised by their material · CPC title

• H01L33/04

  Electricity · mapped topic

• H01L33/002 Primary

  Electricity · mapped topic

• H01L33/40

  Electricity · mapped topic