Method of manufacturing an organic light emitting diode

• US 7,622,864 B2
• Filed: 09/29/2006
• Issued: 11/24/2009
• Est. Priority Date: 09/30/2005
• Status: Active Grant

• Current Assignee: Industry-University Cooperation Foundation Hanyang University, Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Industry-University Cooperation Foundation Hanyang University, Samsung Electronics Co. Ltd.
• Inventors: Kim, Tae-Whan, Choo, Dong-Chul
• Primary Examiner(s): Williams; Joseph L
• Application Number:
  US11/540,389
• Publication Number:
  US 20070075637A1
• Time in Patent Office: 1,152 Days
• Field of Search: 313504-506, 445 23- 25
• US Class Current: 313/506
• CPC Class Codes: H10K 50/17 Carrier injection layers

Abstract

A manufacturing method of an organic light emitting diode (“OLED”) includes forming an anode on a substrate, forming an inorganic buffer layer on the anode, forming a hole transport layer on the buffer layer, forming a light emission layer on the hole transport layer, forming an electron transport layer on the light emission layer, and forming a cathode on the electron transport layer. The forming an inorganic buffer layer includes thermal evaporation and oxidation.

Claims

1. A manufacturing method of an organic light emitting diode, comprising:

forming an anode on a substrate;

forming an inorganic buffer layer, the forming the inorganic buffer layer comprising forming a metal layer on the anode by thermal evaporation and subjecting the formed metal layer to heat treatment;

forming a hole transport layer on the buffer layer;

forming a light emission layer on the hole transport layer;

forming an electron transport layer on the light emission layer; and

forming a cathode on the electron transport layer.

2. The method of claim 1, further comprising:

forming an electron injection layer between the light emission layer and the cathode.

3. The method of claim 1, further comprising:

forming a hole injection layer between the inorganic buffer layer and the hole transport layer.

4. The method of claim 1, wherein the inorganic buffer layer comprises at least one of Ni, Zn, and Mg.

5. The method of claim 1, wherein the heat treatment is performed at about 550°

C. to about 600°

C.

6. The method of claim 1, wherein the buffer layer has a thickness of about 5 nm to 10 nm.

7. The method of claim 1, wherein the anode comprises indium tin oxide.

8. An organic light emitting diode comprising:

a first electrode formed on a substrate;

an inorganic buffer layer formed through forming a metal layer on the first electrode by thermal evaporation and subjecting the formed metal layer to heat treatment;

a first transport layer formed on the first electrodes;

a light emission layer formed on the first transport layers;

a second transport layer formed on the light emission layer;

a first injection layer formed on the second transport layer; and

a second electrode formed on the electron injection layer.

9. The organic light emitting diode of claim 8, wherein

the first and second electrode are an anode and a cathode, respectively;

and

the first and second transport layer are a hole transport layer and an electron transport layer, respectively.

10. The organic light emitting diode of claim 9, wherein

the first injection layer is an electron injection layer.

11. The organic light emitting diode of claim 10, further comprising a second injection layer disposed between the buffer layer and the hole transport layer, the second injection layer being a hole injection layer.

12. The organic light emitting diode of claim 8, wherein the inorganic buffer layer comprises at least one of Ni, Zn, Mg and a combination including at least one of the foregoing.

13. The organic light emitting diode of claim 8, wherein the heat treatment is performed at about 550°

C. to about 600°

C.

14. The organic light emitting diode of claim 8, wherein the buffer layer has a thickness of about 5 nm to 10 nm.

15. The organic light emitting diode of claim 8, wherein the first electrode comprises indium tin oxide.

16. An organic light emitting diode comprising:

a first electrode formed directly on a substrate;

an inorganic buffer layer formed directly on the first electrode;

a hole injection layer formed on the inorganic buffer layer such that the inorganic buffer layer is disposed between the hole injection layer and the first electrode;

a hole transport layer formed on the hole injection layer such that the hole injection layer is disposed between the hole transport layer and the inorganic buffer layer;

a light emission layer formed directly on the hole transport layer;

an electron transport layer formed directly on the light emission layer;

an electron injection layer formed directly on the electron transport layer; and

a second electrode formed directly on the electron injection layer.