KR20160066288A - Organic light emitting display device and method of manufacturing the same - Google Patents

Abstract

Provided is an organic light emitting display device. The organic light emitting display device includes an over coating layer. An anode is placed on the over coating layer. An auxiliary electrode is placed on the over coating layer as placed apart from the anode. A bank layer is placed to cover a side part of the auxiliary electrode and a side part of the anode. A partition is placed on the auxiliary electrode, and includes a pillar part and a roof part. An organic light emitting layer is placed at least on the anode. A cathode is formed at least on the organic light emitting layer, and electrically connected to the auxiliary electrode. According to an embodiment of the present invention, the organic light emitting display device is capable of minimizing a contact area between the auxiliary electrode and the organic light emitting layer by making the roof part of the partition cover the auxiliary electrode, and keeping the brightness uniform by making a contact area between the cathode and the auxiliary electrode uniform.

Description

Technical Field [0001] The present invention relates to an organic light emitting diode (OLED) display device,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting diode (OLED) display and a method of manufacturing the same. More particularly, the present invention relates to an organic light emitting display and a method of manufacturing the same.

The organic light emitting diode (OLED) is a self-emissive type display device, and unlike a liquid crystal display (LCD), a separate light source is not required, so that it can be manufactured in a light and thin shape. Further, the organic light emitting display device is not only advantageous from the viewpoint of power consumption by low voltage driving, but also excellent in color implementation, response speed, viewing angle, and contrast ratio (CR), and is being studied as a next generation display.

The top emission type organic light emitting display device refers to an organic light emitting display device in which light emitted from an organic light emitting device is emitted to an upper portion of the organic light emitting display device, Refers to an organic light emitting display device which emits in the direction of the top surface of a substrate on which a thin film transistor for driving an apparatus is formed. In the case of the top emission type organic light emitting display, a transparent electrode or a transflective electrode is used as a cathode to emit light emitted from the organic light emitting layer. In the case of using the electrode of the transparent characteristic as the cathode and the case of using the electrode of the transflective characteristic, the thickness of the cathode is made thin to improve the transmittance, but the decrease of the cathode thickness increases the electrical resistance of the cathode. In particular, in the case of a large-area organic light emitting display device, the voltage drop becomes more serious as the distance from the voltage supply pad portion increases, and thus the problem of luminance non-uniformity of the organic light emitting display device may arise. In this specification, the voltage drop means a phenomenon in which the potential difference formed in the organic light emitting element decreases, specifically, a phenomenon in which the potential difference between the anode and the cathode of the organic light emitting element decreases.

A method using an auxiliary electrode is used to solve the voltage drop as described above. That is, a method of electrically connecting a separate auxiliary electrode to the cathode is used to prevent the increase of the electrical resistance of the cathode.

A method of forming a reverse tapered barrier rib on the auxiliary electrode in order to electrically connect the auxiliary electrode and the cathode is used. When the step coverage of the material used as the organic light emitting layer is different from the material used as the organic light emitting layer, the material used as the organic light emitting layer is used as an area disposed in an area on the auxiliary electrode covered with the reverse tapered barrier rib, The area where the material is disposed in the region on the auxiliary electrode covered with the reverse tapered barrier ribs is different. As the step coverage of the material used as the cathode is improved than the step coverage of the material used as the organic light emitting layer, the area in which the cathode contacts the auxiliary electrode is increasing.

However, the incident angle at which the material used as the organic light emitting layer is deposited on the organic light emitting display panel differs depending on the source position of the material used as the organic light emitting layer. Particularly, in the large-area top emission organic light emitting display, the incident angle at which the material used as the organic light emitting layer is deposited on the organic light emitting display panel may vary. Specifically, since the source is heated and deposited in the crucible, the deposited incident angle to be deposited based on the position of the crucible in the chamber is determined.

When a material used as the organic light emitting layer is incident at an angle smaller than the reverse taper angle of the barrier rib, the organic light emitting layer is also formed in the region on the auxiliary electrode covered with the barrier rib. In addition, since the deposition angle of the substance used as the organic light emitting layer in the large-area top emission organic light emitting display varies, the area of the organic light emitting layer that can be formed in the region on the auxiliary electrode covered with the barrier can be varied. Depending on the area of the organic light emitting display panel formed on the area of the auxiliary electrode, the area of contact of the cathode with the auxiliary electrode differs depending on the position of the organic light emitting display panel. Accordingly, in the large-area top emission organic light emitting display, the resistance of the cathode may vary according to the position of the organic light emitting display panel, and the luminance depending on the resistance of the cathode may vary, There is a difficult problem. Particularly, as the area of contact between the cathode and the auxiliary electrode decreases, an overcurrent may flow in a narrow contact area, so that a burnt defect may occur.

Accordingly, there is a need for a method of uniformly maintaining the contact area between the auxiliary electrode and the cathode in order to ensure luminance uniformity regardless of the position of the organic light emitting display panel in the large-area top emission organic light emitting display .

[Related Technical Literature]

One. White white light emitting organic electroluminescent display device (Patent Application No. 10-2008-0127996)

2. An encapsulation structure of an OLED device having high permeability and high heat dissipation property and a method for manufacturing the same (Patent Application No. 10-2011-0036930)

The inventors of the present invention have proposed an organic light emitting display device having the same area in which the cathode and the auxiliary electrode are in contact with each other regardless of their positions in the organic light emitting display panel in order to solve the problem that the luminance uniformity is lowered in the organic light emitting display device, And a method of manufacturing the same.

Accordingly, it is an object of the present invention to provide an organic light emitting display device and an organic light emitting display device capable of minimizing an area in which a depression is formed in a barrier rib disposed on an auxiliary electrode, .

Another problem to be solved by the present invention is to provide an organic light emitting display device capable of minimizing the probability of depositing a material used as an organic light emitting layer on an auxiliary electrode at a lower portion of a barrier rib by forming a roof portion and a column portion of the barrier rib, And a method of manufacturing the organic light emitting display device.

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

An organic light emitting display according to an embodiment of the present invention is provided. The organic light emitting display includes an overcoat layer. The anode is disposed on the overcoat layer. The auxiliary electrode is disposed apart from the anode on the overcoat layer. The bank layer is arranged to cover one side of the auxiliary electrode and one side of the anode. The barrier rib is disposed on the auxiliary electrode, and includes a column portion and a roof portion. The organic light emitting layer is disposed at least on the anode. The cathode is formed on at least the organic light emitting layer and is electrically connected to the auxiliary electrode. In the organic light emitting diode display according to an embodiment of the present invention, the roof portion of the barrier rib covers the auxiliary electrode to minimize the contact area of the organic light emitting layer with the auxiliary electrode, and uniform the contact area of the cathode with the auxiliary electrode, The uniformity of the luminance of the display device can be improved.

According to another aspect of the present invention, the column portion and the roof portion are integrally formed.

According to another aspect of the present invention, the barrier rib is characterized in that a depression is formed in a lower portion of the barrier rib.

According to another aspect of the present invention, the columnar section has a rectangular or inverted tapered cross section.

According to another aspect of the present invention, the column and the roof are made of the same material.

According to another aspect of the present invention, the pillars and the roof portions are formed of a negative photoresist.

According to another aspect of the present invention, the column and the roof are physically separated.

According to another aspect of the present invention, the roof section has a rectangular or regular tapered cross section.

According to another aspect of the present invention, the lower surface of the roof portion completely covers the upper surface of the column portion, and the area of the lower surface of the roof portion is larger than that of the upper surface of the column portion.

According to another aspect of the present invention, the area of the upper surface of the column portion and the lower surface of the roof portion is smaller than or equal to the area of the lower surface of the column portion and the upper surface of the auxiliary electrode.

According to another aspect of the present invention, the column and roof portions are made of different materials.

According to another aspect of the present invention, the column portion is made of a non-photosensitive resist and the roof portion is made of a positive photoresist.

According to another aspect of the present invention, there is provided a method of manufacturing an organic light emitting diode display, comprising: forming an auxiliary electrode spaced apart from an anode and an anode on an overcoat layer; forming a bank layer covering one side of the auxiliary electrode and one side of the anode Depositing a negative photoresist on the anode, the auxiliary electrode and the bank layer, exposing using a mask on the negative photoresist, developing the negative photoresist, developing the negative photoresist at a temperature above the critical temperature of the negative photoresist, Curing the resist to form a barrier, forming at least an organic light-emitting layer on the anode, and forming a cathode, which is formed on at least the organic light-emitting layer and is electrically connected to the auxiliary electrode. According to another exemplary embodiment of the present invention, a recess is formed in a lower portion of a barrier rib to reduce the probability of forming an organic emission layer on the auxiliary electrode, The area in contact with the electrode can be kept uniform.

According to another feature of the invention, the mask comprises an opening corresponding to at least a portion of the top of the auxiliary electrode, the step of exposing comprises the steps of disposing a mask on the negative photoresist, And a step of irradiating the light source with the light beam.

According to another aspect of the present invention, the step of forming the barrier includes the step of curing the negative photoresist at a temperature of 100 ° C to 150 ° C for 5 minutes or more.

According to another aspect of the present invention, there is provided a method of fabricating an organic light emitting display, comprising: forming an auxiliary electrode spaced apart from an anode and an anode on an overcoat layer; forming a bank layer covering one side of the auxiliary electrode and one side of the anode; Disposing a non-photosensitive resist on the anode, the auxiliary electrode and the bank layer; placing a positive photoresist on the non-photosensitive resist; exposing using a mask on the positive photoresist; Forming an organic light emitting layer on at least the anode, and forming a cathode at least on the organic light emitting layer and electrically connected to the auxiliary electrode, wherein the developing rate of the positive photoresist ( rate and the development speed of the non-photosensitive resist are different. According to another embodiment of the present invention, a positive photoresist having a low developing speed constitutes a roof portion of a barrier rib, and an area where the cathode contacts the auxiliary electrode regardless of the position of the organic light emitting display panel So that the resistance of the cathode and the luminance of the organic light emitting display can be uniformly ensured.

According to another aspect of the present invention, the developing speed of the non-photosensitive resist is faster than the developing speed of the positive photoresist.

According to another aspect of the present invention, a mask includes a light shielding portion covering at least a part of an upper portion of an auxiliary electrode, and the step of exposing includes the steps of disposing a mask on the positive photoresist and irradiating ultraviolet The method comprising the steps of:

The details of other embodiments are included in the detailed description and drawings.

The organic light emitting display device according to the present invention can minimize the contact area between the auxiliary electrode and the organic light emitting layer in the lower part of the barrier rib regardless of the position of the organic light emitting display panel and uniformly contact the area of the auxiliary electrode and the cathode in the lower part of the barrier rib. .

In addition, the present invention can produce an organic light emitting display capable of ensuring a uniform luminance irrespective of the position of the organic light emitting display panel.

The effects according to the present invention are not limited by the contents exemplified above, and more various effects are included in the specification.

1 is a schematic cross-sectional view illustrating an organic light emitting display according to an embodiment of the present invention.
2 is a flowchart illustrating a method of manufacturing an organic light emitting display according to an exemplary embodiment of the present invention.
3A to 3G are cross-sectional views illustrating a method of manufacturing an organic light emitting display according to an exemplary embodiment of the present invention.
4 is a schematic cross-sectional view illustrating an OLED display according to another embodiment of the present invention.
FIG. 5 is a flowchart illustrating a method of manufacturing an organic light emitting display according to another embodiment of the present invention. Referring to FIG.
6A to 6E are cross-sectional views illustrating a method of manufacturing an organic light emitting display according to another embodiment of the present invention.
7 is a schematic cross-sectional view illustrating an organic light emitting diode display according to another embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, and the like disclosed in the drawings for describing the embodiments of the present invention are illustrative, and thus the present invention is not limited thereto. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Where the terms "comprises", "having", "done", and the like are used in this specification, other portions may be added unless "only" is used. Unless the context clearly dictates otherwise, including the plural unless the context clearly dictates otherwise.

In interpreting the constituent elements, it is construed to include the error range even if there is no separate description.

In the case of a description of the positional relationship, for example, if the positional relationship between two parts is described as 'on', 'on top', 'under', and 'next to' Or " direct " is not used, one or more other portions may be located between the two portions.

It will be understood that when an element or layer is referred to as being on another element or layer, it encompasses the case where it is directly on or intervening another element or intervening another element or element.

Although the first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are used only to distinguish one component from another. Therefore, the first component mentioned below may be the second component within the technical spirit of the present invention.

Like reference numerals refer to like elements throughout the specification.

The sizes and thicknesses of the individual components shown in the figures are shown for convenience of explanation and the present invention is not necessarily limited to the size and thickness of the components shown.

It is to be understood that each of the features of the various embodiments of the present invention may be combined or combined with each other partially or entirely and technically various interlocking and driving is possible as will be appreciated by those skilled in the art, It may be possible to cooperate with each other in association.

Various embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

1 is a schematic cross-sectional view illustrating an organic light emitting display according to an embodiment of the present invention. Referring to FIG. 1, the organic light emitting diode display 100 includes an overcoat layer 110, an organic light emitting diode 120, an auxiliary electrode 130, a bank layer 140, and a barrier 150.

Although not shown in FIG. 1, the overcoat layer 110 has a contact hole for exposing a source electrode or a drain electrode of the thin film transistor. The overcoat layer 110 is a layer for flattening the top of the thin film transistor for driving the organic light emitting diode 120.

Referring to FIG. 1, an anode 121 and an auxiliary electrode 130 are disposed on an overcoat layer 110. Specifically, the anode 121 is disposed on the overcoat layer 110 so as to be electrically connected to the thin film transistor through the contact hole of the overcoat layer 110. Since the OLED display 100 is a top emission type OLED display, the anode 121 includes a reflective layer and a transparent conductive layer. Accordingly, although not shown in FIG. 1, the anode 121 may be formed of a plurality of layers.

The anode 121 is made of a conductive material having a high work function to supply holes to the organic light emitting layer 122. For example, the anode 121 may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), zinc oxide, tin oxide, But not limited to, a transparent conductive oxide (TCO).

Referring to FIG. 1, an auxiliary electrode 130 is disposed on the overcoat layer 110 and spaced apart from the anode 121. Here, the auxiliary electrode 130 may have the same structure as the anode 121 on the overcoat layer 110. That is, the auxiliary electrode 130 may be formed to include a reflective layer and a transparent conductive layer like the anode 121. Accordingly, the auxiliary electrode 130 may be disposed on the overcoat layer 110 to have the same thickness as the anode 121.

The auxiliary electrode 130 is formed to reduce the increased resistance of the cathode 123 as the cathode 123 is made thin. Accordingly, the auxiliary electrode 130 is made of a material capable of reducing the resistance of the cathode 123. That is, the auxiliary electrode 130 is made of a material having small electrical resistance and high conductivity. For example, the auxiliary electrode 130 may include a conductive material having a high work function, such as the anode 121.

Referring to FIG. 1, a bank layer 140 is disposed on the overcoat layer 110. Specifically, the bank layer 140 is disposed so as to cover one side of the auxiliary electrode 130 and one side of the anode 121. The bank layer 140 is disposed so that the auxiliary electrode 130 made of a conductive material and the anode 121 are not electrically connected to each other.

Referring to FIG. 1, the barrier rib 150 is disposed on the auxiliary electrode 130. The partition 150 disposed on the auxiliary electrode 130 includes a column portion 151 and a roof portion 153. The columnar portion 151 contacts the upper surface of the auxiliary electrode 130 to the lower portion of the barrier rib 150. [ The roof portion 153 is connected to an upper portion of the partition wall 150 and an upper portion of the column portion 151. Referring to FIG. 1, in the partition 150, the column 151 and the roof 153 are integrally formed.

The barrier rib 150 is made of photoresist which is an insulating material. Specifically, the barrier rib 150 may be formed of a negative photoresist. That is, the columnar portion 151 and the roof portion 153 in the barrier rib 150 may all be formed of negative photoresist. The formation process of the barrier rib 150 according to the properties of the negative photoresist will be described later with reference to FIGS. 3A to 3G.

Referring to FIG. 1, the partition 150 has a depression 159 formed in a lower portion of the partition 150. Specifically, the depression 159 is a region where the partition 150 is depressed toward the pillar 151 from the outside, and the partition 150 may have various shapes depending on the depression degree. The lower part of the roof part 153 can be protruded toward the auxiliary electrode 130 as the distance from the pillar part 151 is increased by the depressed part 159 and can be increased as it approaches the pillar part 151. Accordingly, the barrier ribs 150 may have an umbrella shape, an overhang, a mushroom shape, or an eave shape. Here, the upper surface of the roof portion 153 may include a curved surface that is not flat, and the cross section of the columnar portion 151 may be reverse tapered.

The barrier ribs 150 are formed to minimize an area where the organic light emitting layer 122 is disposed on the auxiliary electrode 130. That is, the area where the organic light emitting layer 122 is disposed on the auxiliary electrode 130 may vary depending on the shape of the barrier rib 150. 1, the area of the lower surface of the columnar portion 151 and the upper surface of the auxiliary electrode 130 is smaller than the area of the upper surface of the auxiliary electrode 130, As shown in FIG. Both side portions of the roof portion 153 protrude toward the auxiliary electrode 130 and the side walls of the roof portion 153 of the bank 150 and the side walls of the bank layer 140 The space between them becomes narrower. This makes it difficult for the material constituting the organic light emitting layer 122 to enter the space between the side surface of the roof portion 153 of the bank 150 and the inclined surface of the bank layer 140, The light emitting layer 122 becomes difficult to be disposed.

The organic light emitting layer 122 is disposed on the anode 121. [ Referring to FIG. 1, the organic light emitting layer 122 is also disposed on a part of the upper part of the bank layer 140. The material constituting the organic light emitting layer 122 may also be deposited on the barrier ribs 150.

The organic light emitting layer 122 is made of a material having poor step coverage. The organic light emitting layer 122 is disposed only on a part of the upper part of the bank layer 140 but not on the auxiliary electrode 130 under the roof part 153. [

The cathode 123 is disposed on the organic light emitting layer 122. Specifically, the cathode 123 is disposed on the anode 121 and the organic luminescent layer 122 to constitute the organic luminescent element 120. Here, the cathode 123 is made of a conductive material having a low work function to supply electrons to the organic light emitting layer 122. For example, the cathode 123 may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), zinc oxide, tin oxide, (TCO) containing carbon nanotubes (CNTs) and / or a graphene based composition material, but the present invention is not limited thereto.

In addition, the cathode 123 is electrically connected to the auxiliary electrode 130. Specifically, the cathode 123 is disposed so as to cover the bank layer 140, and also on the auxiliary electrode 130 below the roof portion 153 of the partition 150. The cathode 123 may be made of a material having excellent step coverage so as to be in contact with the auxiliary electrode 130 disposed under the roof portion 153 of the barrier rib 150. [ In particular, the cathode 123 is formed of a transparent conductive oxide (TCO), and the transparent conductive oxide (TCO) is formed to be connected to the auxiliary electrode 130 through sputtering. That is, the cathode 123 has a better step coverage than the organic light emitting layer 122 formed by evaporation, and can be formed up to the top of the auxiliary electrode 130 disposed under the barrier ribs 150. Accordingly, the organic light emitting layer 122 can not contact the auxiliary electrode 130 disposed under the roof portion 153 of the partition 150, but the cathode 123 can be disposed on the auxiliary electrode 130 . Also, since the cathode 123 is a conductive material, it is disposed on the auxiliary electrode 130 and electrically connected thereto.

The organic light emitting display device 100 according to an embodiment of the present invention may include a depression 159 at a lower portion of the barrier rib 150 to prevent the organic light emitting layer 122 from being disposed on the auxiliary electrode 130. Specifically, the partition 150 having an umbrella shape by the depression 159 reduces the space between the bank layer 140 and the partition 150. Particularly, both side portions of the roof portion 153 protrude toward the auxiliary electrode 130, and the probability that a material having a poor step coverage is disposed on the auxiliary electrode 130 is greatly reduced. Accordingly, since the organic light emitting layer 122 is made of a material having poor step coverage, the auxiliary electrode 130 under the depression 159 can not be formed. On the other hand, since the cathode 123 is made of a material having a better step coverage than the material of the organic light emitting layer 122, the cathode 123 is also disposed on the auxiliary electrode 130 under the depression 159. That is, the partition wall 150 having the umbrella shape by the depression 159 minimizes the space in which the material constituting the organic light emitting layer 122 can enter. Accordingly, the cathode 123 made of a material having excellent step coverage contacts the auxiliary electrode 130 with a certain area irrespective of the incident angle at which the material constituting the organic light emitting layer 122 is deposited, The voltage drop irregularity due to the resistance variation of the resistor 123 can be reduced. That is, the luminance uniformity of the OLED display 100 can be improved.

2 is a flowchart illustrating a method of manufacturing an organic light emitting display according to an exemplary embodiment of the present invention. 3A to 3G are cross-sectional views illustrating a method of manufacturing an organic light emitting display according to an exemplary embodiment of the present invention. 3A to 3G are process cross-sectional views illustrating a method of manufacturing the organic light emitting diode display 100 shown in FIG. 1, and overlapping descriptions of the components described with reference to FIG. 1 are omitted.

First, the anode 121 and the auxiliary electrode 130 are formed on the overcoat layer 110 (S21).

Referring to FIG. 3A, the anode 121 is formed corresponding to the contact hole of the overcoat layer 110. The auxiliary electrode 130 is formed apart from the anode 121. Here, the anode 121 and the auxiliary electrode 130 may be simultaneously formed by a single patterning process. Accordingly, the anode 121 and the auxiliary electrode 130 may be made of the same material.

Subsequently, the bank layer 140 is formed to cover one side of the auxiliary electrode 130 and one side of the anode 121 (S22).

Referring to FIG. 3B, a bank layer 140 is formed on the overcoat layer 110 to cover one side of the auxiliary electrode 130 and one side of the anode 121. The bank layer 140 insulates an area between the anode 121 and the auxiliary electrode 130 on the overcoat layer 110.

Subsequently, a negative photoresist 350 is disposed on the anode 121, the auxiliary electrode 130, and the bank layer 140 (S23).

Referring to FIG. 3C, the negative photoresist 350 is disposed on the front surface of the organic light emitting display panel so as to cover both the anode 121, the auxiliary electrode 130, and the bank layer 140. The negative photoresist 350 may be disposed in various ways. Specifically, the negative photoresist 350 may be arranged to cover both the anode 121, the auxiliary electrode 130 and the bank layer 140 by spin coating.

Next, the negative photoresist 350 is exposed using the mask 360 on the negative photoresist 350 (S24).

Referring to FIG. 3D, the mask 360 includes an opening 365. The mask 360 is disposed on the negative photoresist 350 such that the opening 365 of the mask 360 corresponds to the upper portion of the auxiliary electrode 130. [ Here, the mask 360 may be disposed such that the opening 365 corresponds to only the upper portion of the auxiliary electrode 130. That is, the mask 360 may be disposed such that the lower region of the opening 365 is overlapped only within the upper region of the auxiliary electrode 130 and is not overlapped with the upper region of the bank layer 140.

Then, ultraviolet light (UV) is irradiated onto the mask 360 through the opening 365 of the mask 360. [ Thus, the ultraviolet ray (UV) is irradiated only to the negative photoresist 350 corresponding to the opening 365. The negative photoresist 350 may change in characteristics due to ultraviolet (UV) light and may not react with the developer.

Subsequently, the negative photoresist 350 is developed (S25).

Referring to FIG. 3E, only the developed negative photoresist 355 of the negative photoresist 350 is disposed on the auxiliary electrode 130. That is, the portion of the negative photoresist 350 irradiated with ultraviolet light (UV) is not reacted with the developing solution, and only the portion not irradiated with ultraviolet light (UV) reacts with the developing solution and is removed. As a result, the negative photoresist 350 irradiated with ultraviolet light (UV) is not removed by the developer, and only the developed negative photoresist 355 remains. In this case, the negative photoresist 355 developed in accordance with the characteristics of the negative photoresist 350 has an inverted taper shape.

Subsequently, the negative photoresist 350 is cured at a temperature equal to or higher than the critical temperature of the negative photoresist 350 to form the barrier 150 (S26).

Referring to FIG. 3F, the developed negative photoresist 355 is cured at a temperature above the critical temperature of the negative photoresist 350 to form a barrier 150 having a curved surface. In general, the critical temperature of the negative photoresist 350 is about 100 占 폚, and the negative photoresist 350 may lose its inherent material properties above the critical temperature. Specifically, the forming temperature of the barrier ribs 150 is higher than the critical temperature of the negative photoresist 350. For example, the forming temperature of the barrier ribs 150 may be 100 ° C to 150 ° C. Thus, if the developed negative photoresist 355 is cured at 100 ° C to 150 ° C, which is the forming temperature of the barrier 150, the shape of the developed negative photoresist 355 can be changed. Specifically, when the negative photoresist 355 developed through the heater or hot plate in the chamber is cured at a temperature of 100 ° C to 150 ° C, the developed negative photoresist 355 is made to have fluidity The shape of the upper portion of the developed negative photoresist 355 is deformed from the top of the developed negative photoresist 355 due to the reverse tapered shape of the developed negative photoresist 355, I can get off. As the curing time elapses, the thickness of the upper portion of the developed negative photoresist 355 is lowered, and the upper portion of the developed negative photoresist 355 spreads to the left and right sides. As the elapsed time increases, some of the sides of the developed negative photoresist 355 may collapse. Here, the barrier rib 150 may have a desired shape by controlling the heating time of the lower portion of the barrier rib 150 at the forming temperature of the barrier rib 150. Accordingly, the developed negative photoresist 355 may be cured to form the barrier ribs 150, and the barrier ribs 150 may have the depressions 159 formed thereunder.

As the depression 159 is formed, the shape of the developed negative photoresist 355 is deformed. Specifically, as the shape of the developed negative photoresist 355 is modified, the barrier rib 150 can be divided into the columnar portion 151 and the roof portion 153. The columnar portion 151 of the partition 150 may have a reverse tapered shape and the upper surface of the roof portion 153 of the partition 150 may be curved. Accordingly, the barrier ribs 150 may have an umbrella shape, an overhang, a mushroom shape, or an eave shape.

Then, an organic light emitting layer 122 is formed on the anode 121 (S27). Next, a cathode 123 is formed on the organic light emitting layer 122 and electrically connected to the auxiliary electrode 130 (S28).

Referring to FIG. 3G, the organic light emitting layer 122 is formed on the anode 121. FIG. The organic luminescent layer 122 may be disposed on a part of the bank layer 140 and the organic luminescent layer 122 may be disposed on the barrier rib 150. However, the organic light emitting layer 122 is made of a material having poor step coverage and is not disposed on the auxiliary electrode 130.

The cathode 123 is disposed on the organic light emitting layer 122 and also on the bank layer 140 and the auxiliary electrode 130. Also, the material constituting the cathode 123 may be disposed on the upper portion of the barrier rib 150. The cathode 123 is formed along the shape of the bank layer 140 and the barrier ribs 150 and is also disposed on the auxiliary electrode 130 because the cathode 123 is made of a material having excellent step coverage. The cathode 123 is formed up to the upper portion of the auxiliary electrode 130 around the columnar portion 151 of the barrier 150 so that the area of the auxiliary electrode 130 where the cathode 123 contacts the auxiliary electrode 130 . The cathode 123 is electrically connected to the auxiliary electrode 130 and the resistance between the voltage supply pad portion and the cathode 123 is reduced by the auxiliary electrode 130. [

In the method of fabricating an OLED display device according to an embodiment of the present invention, the negative photoresist 355 is cured at a temperature equal to or higher than the critical temperature to form barrier ribs 150 having various shapes. Specifically, if the developed negative photoresist 355 is cured for 5 minutes or more at a temperature of 100 占 폚 to 150 占 폚, which is the critical temperature of the negative photoresist 350, the shape of the initially developed negative photoresist 355 The barrier ribs 150 are formed. Accordingly, the barrier ribs 150 may be formed in various shapes such as an umbrella shape, an overhang, a mushroom shape, or an eave shape, and the barrier ribs 150 of various shapes may be formed on the auxiliary electrode 130, It is possible to effectively prevent the material constituting the organic light emitting layer 122 from being incident.

4 is a schematic cross-sectional view illustrating an OLED display according to another embodiment of the present invention. The OLED display 400 of FIG. 4 is different from the OLED display 100 of FIG. 1 only in the shape and configuration of the barrier 450, and the other structures are substantially the same, .

Referring to FIG. 4, the barrier rib 450 has a structure including two layers. Specifically, the partition wall 450 includes a column portion 451 and a roof portion 453. [ The column portion 451 is in contact with the upper surface of the auxiliary electrode 130 and the roof portion 453 is disposed on the column portion 451. The column portion 451 and the roof portion 453 may be a part physically separated from the partition 450. In this case, the column portion 451 and the roof portion 453 may be a part of the partition 450 made of a different material. Specifically, the material constituting the columnar section 451 is a non-photosensitive resist, and the material constituting the roof section 453 may be a positive photoresist. That is, the material constituting the columnar section 451 and the material constituting the roof section 453 are different from each other in light-induced characteristics. Due to the difference in the materials constituting the column portion 451 and the roof portion 453, the column portion 451 and the roof portion 453 have different shapes. The formation process of the column portion 451 and the roof portion 453 due to the difference of materials will be described later with reference to FIGS. 6A to 6E.

4, the cross section of the columnar section 451 is rectangular in shape. Specifically, the shape of the cross section of the columnar section 451 may be a rectangle or a constant taper shape. That is, the area of the upper surface of the column portion 451 and the lower surface of the roof portion 453 may be smaller than or equal to the area of the lower surface of the column portion 451 and the upper surface of the auxiliary electrode 130 . The shape of the cross section of the roof portion 453 is rectangular. Specifically, the shape of the cross section of the roof portion 453 may be a rectangular shape or a constant taper shape.

4, the lower surface of the roof portion 453 completely covers the upper surface of the column portion 451, and the area of the lower surface of the roof portion 453 is wider than that of the upper surface of the column portion 451. [ That is, the roof portion 43 completely covers the upper portion of the column portion 451 and protrudes in the direction parallel to the upper surface of the auxiliary electrode 130 from the center of the column portion 451. The height h of the roof portion 430 may vary depending on the method of disposing the positive photoresist and the length 1 protruding from the column portion 451 of the roof portion 430 may vary depending on the development time . The change of the height h of the roof part 430 and the length l protruding from the column part 451 of the roof part 430 according to the process will be described later with reference to Figs. 6A to 6E.

The probability of the material forming the organic light emitting layer 122 being incident on the upper portion of the auxiliary electrode 130 is greatly reduced according to the shape of the partition 450 including the columnar portion 451 and the roof portion 453. [

The OLED display 400 according to another exemplary embodiment of the present invention may include a columnar portion 451 made of a different material and a partition wall 450 including a roof portion 453, The area of the surface where the cathode 123 and the auxiliary electrode 130 are in contact increases. Specifically, the material constituting the columnar section 451 and the roof section 453 are different, so that the speed at which the material constituting the column section 451 reacts with the developing liquid and the material constituting the roof section 453, And the rate at which they react with each other. The positive photoresist with a low developing speed is used as the material constituting the roof portion 453 and the roof portion 453 is made of the material constituting the column portion 451. In this case, It is possible to completely cover the portion 451 and cover a part of the upper portion of the auxiliary electrode 130. Both side portions of the roof portion 453 protrude from the column portion 451 toward the bank layer 140 and the roof portion 453 of the partition wall 150 and the bank layer 140 is narrowed. This makes it difficult for the material constituting the organic light emitting layer 122 to enter into the space between the roof portion 453 of the bank 450 and the inclined surface of the bank layer 140. The organic light emitting layer 122 are difficult to be disposed. The cathode 123 contacts the auxiliary electrode 130 with a predetermined area irrespective of the incident angle at which the material constituting the organic light emitting layer 122 is deposited so that the voltage supply pad portion and the cathode 123 are electrically connected to the auxiliary electrode 130, The resistance variation in each position can be reduced.

FIG. 5 is a flowchart illustrating a method of manufacturing an organic light emitting display according to another embodiment of the present invention. Referring to FIG. 6A to 6E are cross-sectional views illustrating a method of manufacturing an organic light emitting display according to another embodiment of the present invention. 6A to 6E are process cross-sectional views illustrating a method of manufacturing the organic light emitting diode display 400 shown in FIG. 4, and overlapping descriptions of the components described with reference to FIG. 4 are omitted.

First, the anode 121 and the auxiliary electrode 130 are formed on the overcoat layer 110 (S51). Subsequently, the bank layer 140 is formed to cover one side of the auxiliary electrode 130 and one side of the anode 121 (S52).

The steps S51 and S52 are the same as the steps corresponding to FIGS. 3A and 3B in the manufacturing method of the organic light emitting diode display 100 shown in FIG. 1, Which will be described later.

Next, a non-photosensitive resist 651 is disposed on the anode 121, the auxiliary electrode 130, and the bank layer 140 (S53).

Referring to FIG. 6A, the non-photosensitive resist 651 is disposed on the entire surface of the organic light emitting display panel so as to cover both the anode 121, the auxiliary electrode 130, and the bank layer 140. The non-photosensitive resist 651 may be disposed by spin coating. For example, the non-photosensitive resist 651 may be applied by spin coating at a revolution rate of 250 rpm.

Subsequently, a positive photoresist 653 is disposed on the non-photosensitive resist 651 (S54).

Referring to FIG. 6B, the positive photoresist 653 is arranged to be thinner than the non-photosensitive resist 651. The positive photoresist 653 may also be disposed by spin coating. For example, the positive photoresist 653 may be applied by spin coating at a speed of 300-350 rpm. Accordingly, since the positive photoresist 653 is applied at a higher spinning rate than the non-photosensitive resist 651, it can be disposed thinner than the non-photosensitive resist 651 on the non-photosensitive resist 651. [

Subsequently, the positive photoresist 653 is exposed using the mask 660 on the positive photoresist 653 (S55).

Referring to FIG. 6C, the mask 660 includes a light shielding portion 665. The mask 660 is disposed on the positive photoresist 653 such that the light shielding portion 665 of the mask 660 corresponds to the upper portion of the auxiliary electrode 130. [ Here, the mask 660 may be disposed so that the light-shielding portion 665 corresponds to only the upper portion of the auxiliary electrode 130. [ That is, the mask 660 may be disposed so that the lower region of the light-shielding portion 665 is overlapped only within the upper region of the auxiliary electrode 130 and is not overlapped with the upper region of the bank layer 140.

Subsequently, ultraviolet light (UV) is irradiated onto the mask 660 through a region other than the shielding portion 665 of the mask 660. [ That is, the ultraviolet light (UV) is irradiated onto the positive photoresist 653 through the opening of the mask 660, whereby the positive photoresist 653 corresponding to the light shielding portion 665 is irradiated with ultraviolet (UV) is not irradiated. The ultraviolet light (UV) passed through the opening of the mask 660 is irradiated to the positive photoresist 653 and the non-photosensitive resist 651. The positive photoresist 653 and the non-photosensitive resist 651 may be changed in properties by ultraviolet (UV) and react with the developer.

Then, the positive photoresist 653 and the non-photosensitive resist 651 are developed (S56).

6D, the positive photoresist 653 in the region not irradiated with ultraviolet light (UV) is not removed by the developer, and the positive photoresist 653 in the region irradiated with ultraviolet light (UV) is removed by the developer do. The non-photosensitive resist 651 can be easily removed by the developing solution. The portion of the positive photoresist 653 that is developed and remains becomes the roof portion 453 of the partition wall 450 and the remaining portion of the non-photosensitive resist 651 is developed and the column portion 451 of the partition wall 450, .

Here, the rate at which the non-photosensitive resist 651 is developed by the developing solution (hereinafter, developing rate) is faster than the developing rate of the positive photoresist 653 in the region irradiated with the ultraviolet ray (UV). Further, since the non-photosensitive resist 651 can be easily removed by the developing solution, the non-photosensitive resist 651 is quickly removed by the developer in the region where the positive photoresist 653 is removed. On the other hand, in the region where the positive photoresist 653 is not removed, it takes time for the developer to contact the non-photosensitive resist 651 under the positive photoresist 653, (651) remains. Thus, the longer the development time is, the less the non-photosensitive resist 651 is under the positive photoresist 653 because the rate at which the non-photosensitive resist 651 is removed is faster than the rate at which the positive photoresist 653 is removed. do. That is, as the developing time becomes longer, the column portion 451 of the partition wall 450 becomes thinner and the length 1 protruding from the column portion 451 of the roof portion 430 becomes longer.

Then, an organic light emitting layer 122 is formed on the anode 121 (S56). Next, a cathode 123 is formed on the organic light emitting layer 122 to be electrically connected to the auxiliary electrode 130 (S57).

Referring to FIG. 6E, the organic light emitting layer 122 is formed on the anode 121. FIG. The organic light emitting layer 122 may be disposed on a part of the bank layer 140 and the organic light emitting layer 122 may be disposed on the partition wall 450. However, the organic light emitting layer 122 is made of a material having poor step coverage and is not disposed on the auxiliary electrode 130. The cathode 123 is disposed on the organic light emitting layer 122 and is also disposed on the bank layer 140 and the auxiliary electrode 130. In addition, since the cathode 123 is made of a material having excellent step coverage, the material constituting the cathode 123 may be disposed on the upper and side portions of the barrier ribs 450. Accordingly, since the cathode 123 is formed along the shape of the barrier rib 150 and also on the auxiliary electrode 130, the area in which the cathode 123 and the auxiliary electrode 130 are in contact with each other on the auxiliary electrode 130 is widened All. The cathode 123 is electrically connected to the auxiliary electrode 130 and the resistance between the voltage supply pad portion and the cathode 123 is reduced by the auxiliary electrode 130. [

In the method of manufacturing an organic light emitting diode display according to another embodiment of the present invention, the roof portion 453 is formed by the positive photoresist 653 and the non-photosensitive resist 651, The partition 450 having the lower surface of the roof portion 453 and having an area larger than that of the upper surface of the column portion 451 is formed. Specifically, the developing speed of the positive photoresist 653 forming the upper portion of the barrier rib 450 is slow and the developing speed of the non-photosensitive resist 651 forming the lower portion of the barrier rib 450 is fast. Accordingly, the upper portion of the partition 450 is formed wider than the lower portion of the partition 450 to form the roof portion 453 and the column portion 451. The two-layer structure of the barrier ribs 450 reduces the space between the roof portions 453 and the bank layer 140 to form the organic light-emitting layer 122 having a poor step coverage over the auxiliary electrode 130 It is possible to effectively prevent the material from being incident. This increases the contact area of the cathode 123 with the auxiliary electrode 130 so that the contact area between the cathode 123 and the auxiliary electrode 130 can be constantly maintained regardless of the position of the organic light emitting display panel. And the resistance variation of the cathode 123 is also reduced, so that the organic light emitting display device can secure a uniform luminance.

7 is a schematic cross-sectional view illustrating an organic light emitting diode display according to another embodiment of the present invention. The organic light emitting display 700 of FIG. 7 is different from the organic light emitting display 100 of FIG. 1 in that the material of the cathode 123 is changed and only the configuration of the connecting electrode 724 is added. , So redundant explanations are omitted.

Referring to FIG. 7, the cathode 123 is made of a conductive material having a low work function to supply electrons to the organic light emitting layer 122. Here, the cathode 123 may be formed of a material having low transmittance. For example, the cathode 123 may be formed of an alloy of Ag, Ti, Al, Mo, or Ag and Mg, (CNT) and / or a graphene based composition material.

The connection electrode 724 is disposed so that the cathode 123 can be electrically connected to the auxiliary electrode 130 as the cathode 123 is made of a material having low transmittance and inadequate step coverage. The connection electrode 724 is made of a conductive material having a high light transmittance so as to allow light to pass through the organic light emitting diode 120. Accordingly, the connecting electrode 724 may be formed of a material selected from the group consisting of indium zinc oxide (IZO), indium tin oxide (ITO), indium tin zinc oxide (ITZO), zinc oxide, tin oxide, But it is not limited thereto.

The cathode 123 may be made of a metal material having low transmittance and may be electrically connected to the connection electrode (not shown) in order to electrically connect the auxiliary electrode 130 and the cathode 123. In the OLED display 700 according to another exemplary embodiment of the present invention, 724 are disposed on the cathode 123. Specifically, the cathode 123 made of metal materials having low transmittance may have a low step coverage, but may form a micro-cavity together with the anode 121 and the organic light-emitting layer 122 to increase the luminous efficiency . Accordingly, the connection electrode 724 can be further disposed to reduce the resistance of the cathode 123 while increasing the luminous efficiency by the micro-cavity. The connection electrode 724 is disposed on the auxiliary electrode 130 such that the cathode 123 is electrically connected to the auxiliary electrode 130. The connecting electrode 724 is a conductive material having high light transmittance and is excellent in step coverage. The auxiliary electrode 130 can be easily and electrically connected to the auxiliary electrode 130 under the barrier 150 by the connection electrode 724 while maintaining the micro cavity by the cathode 123. Therefore, The resistance variation of the cathode 123 can be reduced irrespective of the position of the light emitting display panel and brightness uniformity can be secured.

Although the embodiments of the present invention have been described in detail with reference to the accompanying drawings, it is to be understood that the present invention is not limited to those embodiments and various changes and modifications may be made without departing from the scope of the present invention. . Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

100, 400, 700: organic light emitting display
110: overcoat layer
120: Organic light emitting device
121: anode
122: organic light emitting layer
123: cathode
130: auxiliary electrode
140: bank layer
150, 450:
151, 451:
153, 453: roof part
159: Depression
350: Negative photoresist
355: Developed Negative Photoresist
360, 660: mask
365: opening
651: Non-photosensitive resist
653: positive photoresist
665: Light shield
724: connecting electrode

Claims (18)

An overcoat layer;
An anode disposed on the overcoat layer;
An auxiliary electrode disposed on the overcoat layer and spaced apart from the anode;
A bank layer disposed to cover one side of the auxiliary electrode and one side of the anode;
A barrier disposed on the auxiliary electrode, the barrier including a column and a roof;
An organic light emitting layer disposed on at least the anode; And
And at least a cathode formed on the organic light emitting layer and electrically connected to the auxiliary electrode. The method according to claim 1,
Wherein the column portion and the roof portion are integrally formed. 3. The method of claim 2,
Wherein the barrier ribs are formed with depressions at a lower portion of the barrier ribs. 3. The method of claim 2,
Wherein the columnar section has a rectangular or inverted tapered cross section. 3. The method of claim 2,
Wherein the column portion and the roof portion are made of the same material. 6. The method of claim 5,
Wherein the column portion and the roof portion are made of a negative photoresist. The method according to claim 1,
Wherein the column portion and the roof portion are physically separated from each other. 8. The method of claim 7,
Wherein the roof portion has a rectangular or regular tapered cross section. 8. The method of claim 7,
The lower surface of the roof portion completely covers the upper surface of the column portion,
Wherein an area of a bottom surface of the roof portion is larger than an area of an upper surface of the column portion. 8. The method of claim 7,
Wherein an area of a surface of the column portion that is in contact with a lower surface of the roof portion is smaller than or equal to an area of a surface of the column portion that is in contact with an upper surface of the auxiliary electrode. 8. The method of claim 7,
Wherein the column portion and the roof portion are made of different materials. 12. The method of claim 11,
Wherein the column portion is made of a non-photosensitive resist,
Wherein the roof portion is made of a positive photoresist. Forming an anode on the overcoat layer and an auxiliary electrode spaced apart from the anode;
Forming a bank layer to cover one side of the auxiliary electrode and one side of the anode;
Disposing a negative photoresist on the anode, the auxiliary electrode, and the bank layer;
Exposing the negative photoresist using a mask;
Developing the negative photoresist;
Curing the negative photoresist at a temperature equal to or higher than a critical temperature of the negative photoresist to form a partition;
Forming an organic light emitting layer on at least the anode; And
And forming a cathode that is disposed on at least the organic light emitting layer and is electrically connected to the auxiliary electrode. 14. The method of claim 13,
Wherein the mask includes an opening corresponding to at least a portion of an upper portion of the auxiliary electrode,
Wherein the step of exposing comprises:
Disposing the mask on the negative photoresist; And
And irradiating ultraviolet light onto the mask through the opening of the mask. 14. The method of claim 13,
Wherein the step of forming the barrier includes curing the negative photoresist at a temperature of 100 DEG C to 150 DEG C for 5 minutes or more. Forming an anode on the overcoat layer and an auxiliary electrode spaced apart from the anode;
Forming a bank layer to cover one side of the auxiliary electrode and one side of the anode;
Disposing a non-photosensitive resist on the anode, the auxiliary electrode, and the bank layer;
Disposing a positive photoresist on the non-photosensitive resist;
Exposing the positive photoresist using a mask;
Developing the non-photosensitive resist and the positive photoresist;
Forming an organic light emitting layer on at least the anode; And
Forming a cathode formed on at least the organic light emitting layer and electrically connected to the auxiliary electrode,
Wherein the developing rate of the positive photoresist is different from the developing rate of the non-photosensitive resist. 17. The method of claim 16,
Wherein the developing speed of the non-photosensitive resist is faster than the developing speed of the positive photoresist. 17. The method of claim 16,
Wherein the mask includes a light shielding portion covering at least a part of an upper portion of the auxiliary electrode,
Wherein the step of exposing comprises:
Disposing the mask on the positive photoresist; And
And irradiating ultraviolet light onto the mask through the mask.

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