Organic Light Emitting Component, and Production Method

• US 20090309492A1
• Filed: 09/03/2007
• Published: 12/17/2009
• Est. Priority Date: 09/04/2006
• Status: Abandoned Application

• Current Assignee: Novaled AG, Evonik Degussa GmbH (Rag-Stiftung)
• Original Assignee: Novaled AG, Evonik Degussa GmbH (Rag-Stiftung)
• Inventors: Adam, Dieter, Inhester, Martina, Birnstock, Jan, Hofmann, Michael, Luethge, Thomas
• Application Number:
  US12/439,796
• Publication Number:
  US 20090309492A1
• Time in Patent Office: Days
• US Class Current: 313/504
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H10K 2102/101 comprising transparent conductive oxides [TCO]
• CPC Class Codes: H10K 2102/102 comprising tin oxides, e.g. fluorine-doped SnO2
• CPC Class Codes: H10K 2102/331 Nanoparticles used in non-emissive layers, e.g. in packaging layer
• CPC Class Codes: H10K 50/155 comprising dopants
• CPC Class Codes: H10K 50/165 comprising dopants
• CPC Class Codes: H10K 50/81 Anodes
• CPC Class Codes: H10K 50/858 comprising refractive means, e.g. lenses
• CPC Class Codes: H10K 71/611 using printing deposition, e.g. ink jet printing

Abstract

The invention relates to an organic light emitting component, particularly an organic light emitting diode, in which an arrangement is formed that comprises a bottom electrode, a top electrode, and an organic layer region which is located between and is in electrical contact with the bottom electrode and the top electrode and contains at least one hole transport layer, at least one electron transport layer, and a light-emitting area. The bottom electrode is formed from a dispersion as a structured, binder-free, and optically transparent bottom electrode layer made of a bottom electrode material by means of a wet chemical application process, said bottom electrode material being an optically transparent, electrically conductive oxide. The bottom electrode layer has a sheet resistance of less than about 500 Ω/square and an optical refractive index of less than 1.8.

Claims

1. An organic light-emitting component, especially an organic light-emitting diode, in which an arrangement with a base electrode and a cover electrode as well as an organic layer region is formed that is arranged between the base electrode and the cover electrode and in electrical contact with the base electrode and the cover electrode, and which comprises at least one hole transport layer, at least one electron transport layer and one light-emitting region, in which:

the base electrode is formed by wet-chemical application from a dispersion as a structured, optically transparent base electrode layer free of binding agent from a base electrode material, namely, an optically transparent, electrically conductive oxide,

the base electrode layer has a surface resistance of less that approximately 500 Ω

/square,

the base electrode layer has an optical refraction index of less than 1.8, and

a reverse blocking current less than approximately 10-2 mA/cm2 is in a current-voltage characteristic of the arrangement at a voltage of approximately −

3V applied on the arrangement.

2. The component according to claim 1, characterized in that the base electrode material is formed by nanoparticles of electrically conductive materials.

3. The component according to claim 1, characterized in that the base electrode material is material of at least one material class selected from the following group of material classes:

ternary material system such as In2O3;

Sn (ITO), SnO₂;

Sb (ATO), SnO2;

F, ZnO;

Al, ZnO;

In, Zn—

Sn—

O, Mg—

In—

O, Ga—

In—

O, Zn—

In—

O;

quarternary material systems such as Zn—

In—

Sn—

O (ZITO), Zn—

In—

Li—

O, chemically modified variant of the ternary material system, chemically modified variant of the quarternary material system, physically modified variants of the ternary material system, physically modified variants of the quarternary material system, and their mixtures.

4. The component according to claim 1, characterized in that the base electrode layer has a layer thickness between approximately 0.05 μ

m and approximately 20 μ

m, preferably between approximately 0.1 μ

m and approximately 2 μ

m.

5. The component according to claim 1, characterized in that the base electrode layer has an RMS roughness in the range of at least approximately 2 nm to at the most approximately 20 nm and preferably in the range of at the most approximately 10 nm.

6. The component according to claim 1, characterized in that the surface resistance of the base electrode layer is less than approximately 100 Ω

/square.

7. The component according to claim 1, characterized in that the optical refraction index of the base electrode layer is less than approximately 1.5.

8. The component according to claim 1, characterized in that the base electrode layer scatters light and is formed with a material porosity between approximately 1% and approximately 99%, preferably between approximately 20% and approximately 60%.

9. The component according to claim 1, characterized in that the base electrode layer has a transmission capacity of at least 60% and preferably of at least 80% in the wavelength range of visible light.

10. The component according to claim 1, characterized in that the organic layer range between the base electrode and the light-emitting region comprises at least one layer with a layer thickness of at least 100 nm that transports charge carriers, with which a surface roughness of the base electrode layer is at least partially compensated.

11. The component according to claim 10, characterized in that the at least one layer transporting charge carriers is electrically doped.

12. The component according to claim 1, characterized in that the arrangement according to at least one construction type is selected from the following group of construction types:

Transparent construction;

construction emitting light through the cover electrode;

construction emitting light through the base electrode;

construction with a layer arrangement with a non-inverted structure in which the base electrode is an anode; and

construction with a layer arrangement with an inverted structure in which the base electrode is a cathode.

13. The component according to claim 1, characterized in that the organic layer comprises one or more layers that are selectively multiply formed, selected from the following group of layers:

Electrically non-doped charge carrier transport layer, electrically doped charge carrier transport layer such as p-doped and n-doped charge carrier transport layer, block layer, electrically non-doped charge carrier injection layer and electrically doped charge carrier injection layer.

14. The component according to claim 1, characterized in that that the arrangement is formed on a carrier material selected from the following group of carrier materials:

glass, flexible carrier material, metallic carrier material, plastic.

25. An article in a construction type selected from the following group of construction types:

Illumination apparatus, display apparatus such as display or contact-sensitive surface, and characterizing device such as label or icon, characterized by at least one organic electronic component in accordance with claim 1.

15. A process for producing an organic light-emitting component, especially an organic light-emitting diode, in which an arrangement with a base electrode and a cover electrode as well as an organic layer region is formed that is arranged between the base electrode and the cover electrode and in electrical contact with the base electrode and the cover electrode, and which is formed with at least one hole transport layer, at least one electron transport layer and one light-emitting region, in which process the base electrode is formed wet-chemically from a dispersion of a base electrode material as a structured base electrode layer free of binding agent from a base electrode material, namely, an optically transparent, electrically conductive oxide, and in which the base electrode layer and the arrangement are configured in accordance with the following features:

(i) A surface resistance of the base electrode layer is smaller than approximately 500 Ω

/square, (ii) an optical refraction index of the base electrode layer is smaller than 1.8, and (iii) a inverse current is less than approximately 10-2 mA/cm2 in a current-voltage characteristic of the arrangement at a voltage of approximately −

3 V applied on the arrangement.

16. The process according to claim 15, characterized in that that the base electrode layer is printed on in a structured manner by a structuring process selected from the following group of structuring processes:

Inkjet printing, offset printing, engraved printing, intaglio printing, thermotransfer printing, laser printing, flexo printing, silk screen printing and tampon printing.

17. The process according to claim 15, characterized in that the base electrode layer is subsequently treated after the wet-chemical application from the dispersion of the base electrode material.

18. The process according to claim 17, characterized in that that the base electrode layer is sintered during the subsequent treatment at a temperature in a range between approximately 200°

C. and approximately 1500°

C., preferably between approximately 200°

C. and approximately 800°

C. and more preferably between approximately 300°

C. and approximately 650°

C. under gaseous atmosphere.

19. The process according to claim 18, characterized in that that the gaseous atmosphere during the sintering comprises at least one gas selected from the following group of gasses:

Ambient air, at least one protective gas such as argon, CO2, nitrogen, noble gas and other non-reactive gas such as perhalogenated hydrocarbons.

20. The process according to one of the claim 17, characterized in that the base electrode layer is formed during the subsequent treatment at a temperature in the range between approximately 20°

C. and approximately 500°

C. and preferably between approximately 150°

C. and approximately 400°

C. under a further gaseous atmosphere selectively formed equal to the gaseous atmosphere in the ratio of 99.9;

0.1 to 0.1;

99.9.

21. The process according to claim 20, characterized in that the further gaseous atmosphere comprises during the forming at least one gas selected from the following group of gases:

hydrogen and at least one protective gas such as argon, CO2, nitrogen, noble gas.

22. The process according to one of the claim 15, characterized in that the organic layer range is formed consisting exclusively of vapor-deposited, low molecular layers.

23. The process according to one of the claim 15, characterized in that the cover electrode is formed by sputtering or thermal vaporization of a cover electrode material.

24. The process according to one of the claim 15, characterized in the organic, light-emitting component is produced in a roller-to-roller process.