TRANSPARENT CONDUCTIVE LAYER STRUCTURE OF LIGHT EMITTING DIODE

• US 20160087157A1
• Filed: 09/24/2014
• Published: 03/24/2016
• Est. Priority Date: 09/24/2014
• Status: Active Grant

• Current Assignee: Tekcore Co Limited (Tekcore)
• Original Assignee: Tekcore Co Limited (Tekcore)
• Inventors: HSU, Hai-Wen, YANG, Ruei-Ming
• Granted Patent: US 9,478,711 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 33/145 with a current-blocking structure
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector

Abstract

A transparent conductive layer structure for an LED is provided. The LED includes a reflecting layer, an N-type electrode, an N-type semiconductor layer, a light emitting layer, a P-type semiconductor layer, a current block layer, a transparent conductive layer and a P-type electrode that are stacked on a substrate. The current block layer is disposed between and separates the P-type electrode and the P-type semiconductor layer. The transparent conductive layer is disposed between the P-type electrode and the current block layer, and connects to the P-type electrode and the P-type semiconductor layer. At a region corresponding to the P-type electrode, a plurality of holes are disposed at the transparent conductive layer to reduce an area of and hence an amount of light absorbed by the transparent conductive layer, thereby increasing light extraction efficiency of excited light from the light emitting layer and enhancing light emitting efficiency of the LED.

Claims

1. A transparent conductive layer structure of a light emitting diode (LED), applied to an LED, the LED comprising a reflecting layer, an N-type electrode, an N-type semiconductor layer, a light emitting layer, a P-type semiconductor layer, a current block layer, a transparent conductive layer and a P-type electrode that are stacked on a substrate;

the reflecting layer located on the substrate, the N-type semiconductor layer located on the reflecting layer, the N-type semiconductor layer comprising divided areas respectively connected to the N-type electrode and the light emitting layer, the P-type semiconductor layer located on the light emitting layer, the current block layer located on the P-type semiconductor layer and having a pattern corresponding to and completely covering the P-type electrode, the transparent conductive layer covering the current block layer and connected to the P-type semiconductor layer, the P-type electrode located on the transparent conductive layer;

the transparent conductive layer structure being characterized that;

at a region corresponding to the P-type electrode, the transparent conductive layer is disposed with a plurality of holes.

2. The transparent conductive layer structure of an LED of claim 1, wherein the region of the transparent conductive layer disposed with the plurality of holes is extended to correspond to the current block layer.

3. The transparent conductive layer structure of an LED of claim 2, wherein a ratio of a width of the plurality of holes to a width of the current block layer is 0.1 to 1.

4. The transparent conductive layer structure of an LED of claim 1, wherein the P-type electrode is divided into a contact area that is in contact with the transparent conductive layer and a non-contact area that is not in contact with the transparent conductive layer, an area of the non-contact area being 0.15% to 80% of that of the contact area.

5. The transparent conductive layer structure of an LED of claim 1, wherein the plurality of holes have a constant area size, and a number of the plurality of holes gets larger as a size of the LED becomes larger.

6. The transparent conductive layer structure of an LED of claim 1, wherein the plurality of holes are evenly distributed on the region corresponding to the P-type electrode.

7. The transparent conductive layer structure of an LED of claim 1, wherein the P-type electrode is divided into a P-type joint and a P-type extension electrode that are connected to each other, and the plurality of holes are disposed on the region corresponding to the P-type joint and the P-type extension electrode.

8. The transparent conductive layer structure of an LED of claim 7, wherein the P-type joint is a circle, and the P-type extension electrode is a long quadrilateral.

9. The transparent conductive layer structure of an LED of claim 1, wherein at the region with the plurality of holes, the P-type electrode is in direct contact with the current block layer.

10. The transparent conductive layer structure of an LED of claim 1, wherein the transparent conductive layer is made of indium tin oxide (ITO), aluminum-doped zinc oxide (AZO) or fluoride-doped tin oxide (FTO).