KR102285679B1 - Organic light emitting diode device - Google Patents

Abstract

a lower electrode, an organic light emitting layer on the lower electrode, an upper electrode on the organic light emitting layer, a passivation layer disposed on the upper electrode to be spaced apart from the upper electrode, a barrier rib for providing a chamber between the upper electrode and the passivation layer, and the Provided in a chamber, an organic light emitting diode device including a micro lens array disposed on the upper surface of the upper electrode, the interior of the chamber may be maintained in a vacuum state or may be filled with an inert gas.

Description

Organic light emitting diode device {ORGANIC LIGHT EMITTING DIODE DEVICE}

The present invention relates to an organic light emitting diode device, and more particularly, to a light extraction structure of the organic light emitting diode device.

Recently, as the size of the display device increases, the demand for a flat display device that occupies less space is increasing. BACKGROUND ART As one of the flat panel display devices, an organic light emitting diode (OLED) device is rapidly developing. An organic light emitting diode device generates an exciton by recombination of holes and electrons provided from an anode and a cathode in an organic light emitting layer, and when the exciton is deactivated, light of a specific wavelength is emitted. or video, etc. The organic light emitting diode device has the advantage of having a wide viewing angle and excellent contrast as well as a fast response speed, and thus attracts attention as a next-generation display device. In addition, the organic light emitting diode device is a self-emission type display device, and since it can be driven at a low voltage, it has an advantage of low power consumption.

The light emitted from the organic light emitting layer may not be emitted to the outside of the substrate because it is trapped within each layer and is waveguided for reasons such as total reflection while passing through the interface between layers having different refractive indices. In this way, the light trapped in each layer in the organic light emitting diode device and guided inside the layer is called waveguided light, and the light trapped in the glass substrate is called substrate mode light. It is said In a panel-type surface light source device, converting waveguide mode light and substrate mode light trapped inside the device and substrate into emission mode light and emitting it to the outside of the device is called light extraction.

An object of the present invention is to provide an organic light emitting diode device having high light extraction efficiency.

Another object to be solved by the present invention is to provide an organic light emitting diode device with improved stability.

The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

An organic light emitting diode device according to embodiments of the present invention for solving the above technical problems is disposed on a lower electrode, an organic light emitting layer on the lower electrode, an upper electrode on the organic light emitting layer, and spaced apart from the upper electrode on the upper electrode It may include a protective layer to be used, a barrier rib providing a chamber between the upper electrode and the protective layer, and a microlens array provided in the chamber and disposed on the upper surface of the upper electrode. The interior of the chamber may be maintained in a vacuum state or may be filled with an inert gas.

The organic light emitting diode device according to embodiments of the present invention may have a space between the microlenses and the protective layer having a large difference in refractive index from the microlenses. Accordingly, light extraction efficiency of light scattered from the microlenses may be increased. As light extraction of the microlenses increases, scattering of light from the microlenses may increase, and optical characteristics according to the viewing angle of the organic light emitting diode device may be improved.

According to embodiments of the present invention, the space inside the chamber may have a refractive index similar to that of the atmosphere outside the device. Accordingly, when light extracted from the microlenses passes through the protective layer, light absorption by the protective layer may be small.

According to the present invention, the protective layer is disposed to be spaced apart from the organic light emitting layer, so that the organic light emitting layer can be protected from external air or external impact.

1 is a cross-sectional view illustrating an organic light emitting diode device according to embodiments of the present invention.
2 and 3 are plan views illustrating an organic light emitting diode device according to embodiments of the present invention.
4 is a cross-sectional view illustrating an organic light emitting diode device according to embodiments of the present invention.

In order to fully understand the configuration and effects of the present invention, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and may be embodied in various forms and various modifications may be made. However, it is provided so that the disclosure of the present invention is complete through the description of the present embodiments, and to completely inform those of ordinary skill in the art to which the present invention belongs, the scope of the invention. Those of ordinary skill in the art will understand that the inventive concept may be practiced in any suitable environment.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. As used herein, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, 'comprises' and/or 'comprising' refers to the presence of one or more other components, steps, operations and/or elements mentioned. or addition is not excluded.

In this specification, when a film (or layer) is referred to as being on another film (or layer) or substrate, it may be formed directly on the other film (or layer) or substrate or a third film (or layer) between them. or layer) may be interposed.

In various embodiments of the present specification, the terms first, second, third, etc. are used to describe various regions, films (or layers), etc., but these regions and films should not be limited by these terms. do. These terms are only used to distinguish one region or film (or layer) from another region or film (or layer). Accordingly, a film quality referred to as a first film quality in one embodiment may be referred to as a second film quality in another embodiment. Each embodiment described and illustrated herein also includes a complementary embodiment thereof. Parts indicated with like reference numerals throughout the specification indicate like elements.

Unless otherwise defined, terms used in the embodiments of the present invention may be interpreted as meanings commonly known to those of ordinary skill in the art.

Hereinafter, an organic light emitting diode device according to the concept of the present invention will be described with reference to the drawings.

1 is a cross-sectional view illustrating an organic light emitting diode device according to embodiments of the present invention. 2 and 3 are plan views illustrating an organic light emitting diode device according to embodiments of the present invention. FIG. 1 corresponds to cross-sections taken along line I-I' of FIGS. 2 and 3 . For convenience of description, some components of the organic light emitting diode are omitted in FIGS. 2 and 3 .

Referring to FIG. 1 , the organic light emitting diode device may be an active matrix device. For example, each organic light emitting diode device may have individually driven pixels.

A substrate 10 may be provided. The substrate 10 may have a pixel area PA. The pixel area PA of the substrate 10 may be defined as an area in which a pixel of the organic light emitting diode device is provided. In some embodiments, a plurality of pixel areas PA may be provided. In this case, the pixels of the organic light emitting diode device may be provided in a one-to-one correspondence in the pixel areas PA of the substrate 10 provided in plurality. Hereinafter, for convenience of description, one pixel will be described as a reference.

The circuit unit 22 may be disposed on the substrate 10 . The circuit unit 22 may be disposed in the pixel area PA. The circuit unit 22 may include a thin film transistor (TFT). The circuit portion 22 may be covered by an overcoat layer 26 .

A protective layer 80 may be disposed on the overcoat layer 26 . The protective layer 80 may be spaced apart from the overcoat layer 26 . The protective layer 80 may include a transparent substrate. The protective layer 80 may protect the organic light emitting layer 50 and the micro lenses 72 to be described later from external air and external impact.

A partition wall 30 may be disposed between the overcoat layer 26 and the passivation layer 80 . The barrier rib 30 may surround the edge of the pixel area PA of the substrate 10 in a plan view. As shown in FIG. 2 , the partition wall 30 may have a grid shape in a plan view. Alternatively, as shown in FIG. 3 , the barrier rib 30 may have linear patterns extending in one direction. The sidewall of the partition wall 30 may be inclined with respect to the upper surface of the overcoat layer 26 . According to another embodiment, the sidewall of the partition wall 30 may be perpendicular to the top surface of the overcoat layer 26 . The barrier rib 30 may provide a chamber C between the overcoat layer 26 and the protective layer 80 . In detail, the barrier rib 30 may separate the overcoat layer 26 and the passivation layer 80 , and may seal between the overcoat layer 26 and the passivation layer 80 . The inside of the chamber (C) may be filled with an inert gas, or may be in a vacuum state. For example, a lamination process for adhesion of the protective layer 80 and the barrier rib 30 may be performed under an inert gas atmosphere. Accordingly, the inside of the chamber (C) may be filled with an inert gas. Alternatively, a lamination process for bonding the protective layer 80 and the barrier rib 30 may be performed in a vacuum atmosphere. Accordingly, the interior of the chamber C may have a vacuum atmosphere. The partition wall 30 may be transparent. The refractive index of the barrier rib 30 may be 1.5 to 1.8.

An adhesive layer 82 may be provided between the partition wall 30 and the protective layer 80 . For example, the adhesive layer 82 may be provided between the upper surface of the barrier rib 30 and the lower surface of the passivation layer 80 to adhere the barrier rib 30 and the passivation layer 80 . The adhesive layer 82 may include a thermosetting adhesive material, a photocurable adhesive material, or a pressure adhesive material.

A lower electrode 40 may be disposed in the chamber C. The lower electrode 40 may be disposed on the upper surface of the overcoat layer 26 . The lower electrode 40 may be electrically connected to the circuit unit 22 . For example, the lower electrode 40 may be connected to the circuit portion 22 through a conductive via 24 passing through the overcoat layer 26 . The lower electrode 40 may include a metal or a transparent conductive material.

An organic light emitting layer 50 may be disposed on the lower electrode 40 . The organic emission layer 50 may include a hole injection layer, a hole transport layer, an emission layer, an electron transport layer, and an electron injection layer. When the lower electrode 40 is an anode, the organic emission layer 50 may be stacked in the order of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. Alternatively, when the lower electrode 40 is a cathode, the organic light emitting layer 50 may be stacked in the order of an electron injection layer, an electron transport layer, a light emitting layer, a hole transport layer, and a hole injection layer. The organic emission layer 50 may generate light by receiving electrons and holes from the lower electrode 40 and the upper electrode 60 to be described later. Light generated from the organic emission layer 50 may be radiated to the outside through the passivation layer 80 . The organic light emitting layer 50 includes polyfluorene, (poly) paraphenylenevinylene, polyphenylene, polyvinylcarbazole, polythiophene, Anthracene, butadiene, tetracene, distyrylarylene, benzazole or carbazole, or derivatives thereof may be included. The hole injection layer, the hole transport layer, the electron transport layer, and the electron injection layer may be omitted if necessary.

An upper electrode 60 may be disposed on the organic emission layer 50 . The upper electrode 60 may include a transparent conductive material. For example, the upper electrode 60 may include indium tin oxide (ITO) or fluorine-doped tin oxide films (FTO). The upper electrode 60 may be a counter electrode of the lower electrode 40 . The upper electrode 60 and the lower electrode 40 may provide electrons and holes to the organic emission layer 50 .

A plurality of micro lenses 72 may be provided on the upper electrode 60 . The micro lenses 72 may be included in a micro lens array arranged in a matrix form. The upper surfaces of the micro lenses 72 may be curved. The refractive index of the micro lenses 72 may be 1.6 to 1.8. The micro lenses 72 may include an organic material or an organometallic compound. In this case, the organic material or the organometallic compound may be a material having a pi-conjugation bond. For example, the micro lenses 72 may include benzene, naphthalene, phenanthrene, biphenyl, quinolone, fluorine, or phenylpyrazole. , phenanthroline, quinodimethane, quinoxaline, indolocarbazole, carbazole, spirobifluorene, pyridine, thi thiophene, dibenzothiophene, furan, diazafluoren, benzofuropyridine, triazine, anthracene, pyrene, Benzothiazole, coumarin, quinacridone, phenylpyridine, oxadiazole, phenoxazine, or derivatives thereof may be included. Alternatively, the micro lenses 72 are NPB (N, N′-Di(1-naphthyl)-N, N′-diphenyl-(1, 1′-biphenyl)-4, 4′-diamine), aluminum oxynate (Tris-(8-hydroxyquinoline) aluminum), or derivatives thereof. The microlenses 72 may control a path of light emitted from the organic emission layer 50 . For example, the micro lenses 72 may scatter light into the chamber (C).

The organic light emitting diode device may include a light refraction control layer 74 or a thin film encapsulation layer 76 disposed between the upper electrode 60 and the micro lenses 72 . The refractive index of the light refraction control layer 74 may be 1.6 to 1.8. The light refraction control layer 74 may improve light extraction efficiency of light emitted from the organic light emitting layer 50 . The thin film encapsulation layer 76 may protect the organic light emitting layer 50 from external oxygen or moisture. According to embodiments of the present invention, either one of the light refraction control layer 74 and the thin film encapsulation layer 76 may be provided, or the light refraction control layer 74 and the thin film encapsulation layer 76 may not be provided.

An organic light emitting diode device, which is an active matrix device, has been described with reference to FIG. 1, but the present invention is not limited thereto. The organic light emitting diode device according to embodiments of the present invention may be a surface light source device. For example, the organic light emitting diode device may include pixels driven collectively or a single light source having a large area. 4 is a cross-sectional view illustrating an organic light emitting diode device according to embodiments of the present invention. For convenience of description, description of overlapping contents is omitted.

Referring to FIG. 4 , the lower electrode 40 , the organic emission layer 50 , and the upper electrode 60 may be sequentially disposed on the substrate 10 . The lower electrode 40 , the organic emission layer 50 , and the upper electrode 60 may cover the upper surface of the substrate 10 . A protective layer 80 may be disposed on the upper electrode 60 . The protective layer 80 may be spaced apart from the upper electrode 60 .

The barrier rib 30 may be disposed between the upper electrode 60 and the protective layer 80 . In this case, the barrier rib 30 may be disposed on the upper surface of the upper electrode 60 . The barrier rib 30 may provide a chamber C between the upper electrode 60 and the protective layer 80 . In detail, the barrier rib 30 may separate the upper electrode 60 and the protective layer 80 , and may seal between the upper electrode 60 and the protective layer 80 . The inside of the chamber (C) may be filled with an inert gas, or may be in a vacuum state. The partition wall 30 may have a grid shape in a plan view or may have linear patterns extending in one direction.

Micro lenses 72 may be provided in the chamber C. The micro lenses 72 may be disposed on the upper surface of the upper electrode 60 . The micro lenses 72 may be included in a micro lens array arranged in a matrix form.

In the organic light emitting diode device according to embodiments of the present invention, the inner space of the chamber C between the microlenses 72 and the protective layer 80 may be in a vacuum state or may be filled with an inert gas. The space may have a large difference in refractive index from the microlenses 72 . For example, the space inside the chamber C may have a refractive index of about 1.0, and the microlenses 72 may have a refractive index of 1.6 to 1.8. Accordingly, light extraction efficiency of light traveling from the microlenses 72 into the chamber C may be increased. As light extraction of the microlenses 72 increases, scattering of light from the microlenses 72 may increase, and optical characteristics according to the viewing angle of the organic light emitting diode device may be improved.

According to embodiments of the present invention, the space inside the chamber C may have a refractive index similar to that of the atmosphere outside the device. Accordingly, when light extracted from the microlenses 72 passes through the protective layer 80 , light absorption by the protective layer 80 may be small.

According to the present invention, the protective layer 80 may be disposed to be spaced apart from the organic emission layer 50 . Accordingly, the organic light emitting layer 50 may be protected from external air (eg, containing oxygen or hydrogen) or external impact.

In the above, embodiments of the present invention have been described with reference to the accompanying drawings, but those of ordinary skill in the art to which the present invention pertains may practice the present invention in other specific forms without changing its technical spirit or essential features. You will understand that there is Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

10: substrate 22: circuit part
30: barrier rib 40: lower electrode
50: organic light emitting layer 60: upper electrode
72: micro lens 80: protective layer

Claims (10)

Board;
a lower electrode on the substrate;
an organic light emitting layer on the lower electrode;
an upper electrode on the organic light emitting layer;
a protective layer disposed on the upper electrode and spaced apart from the upper electrode;
a barrier rib providing at least one chamber between the upper electrode and the protective layer; and
Provided in the chamber, including a micro lens array disposed on the upper surface of the upper electrode,
The interior of the chamber is maintained in a vacuum state or filled with an inert gas,
the barrier rib extends from a lower surface of the protective layer toward the substrate through the upper electrode, the organic light emitting layer, and the lower electrode;
An organic light emitting diode device in which a region surrounded by the barrier rib is defined as one pixel in a plan view. delete The method of claim 1,
The barrier rib has a grid shape in a plan view, or an organic light emitting diode device having linear patterns extending in one direction. delete The method of claim 1,
An organic light emitting diode device having a refractive index of 1.5 to 1.8 of the barrier rib. The method of claim 1,
between the substrate and the lower electrode,
The organic light emitting diode device further comprising: a circuit portion disposed on the substrate; and an overcoat layer covering the circuit portion on the substrate. The method of claim 1,
The organic light emitting diode device further comprising a light refraction control layer provided between the upper electrode and the microlens. The method of claim 1,
The protective layer is an organic light emitting diode device including a transparent substrate. a substrate having a pixel area;
a circuit portion on the substrate;
an overcoat layer covering the circuit unit on the substrate;
a protective layer on the overcoat layer;
a partition wall separating the overcoat layer and the protective layer from each other and enclosing an edge of the pixel area in a plan view; and
A lower electrode, an organic light emitting layer and an upper electrode sequentially stacked on the overcoat layer in a space between the overcoat layer and the protective layer,
The space defined by the overcoat layer, the protective layer and the barrier rib is maintained in a vacuum state or filled with an inert gas,
The barrier rib penetrates the upper electrode, the organic light emitting layer, and the lower electrode to contact the overcoat layer. 10. The method of claim 9,
and a micro lens array disposed on an upper surface of the upper electrode in a space between the overcoat layer and the protective layer.

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