KR102482986B1 - Organic light emitting display device and method of manufacturing the same - Google Patents

Abstract

The present invention relates to an organic light emitting display device capable of reducing the resistance of a second electrode and preventing corrosion and metal transition of a pad electrode while not adding or reducing a mask process, and a manufacturing method thereof, In the organic light emitting display device according to the present invention, the auxiliary wire is connected to the second electrode through an auxiliary electrode provided on the same layer as the first electrode, and the pad cover electrode is a pad so that the pad connection electrode connected to the pad is not exposed to the outside. Cover the top and side surfaces of the connecting electrode.

Description

Organic light emitting display device and manufacturing method thereof

The present invention relates to an organic light emitting display device and a method for manufacturing the same, and more particularly, to reduce the resistance of a second electrode and prevent corrosion and metal transition of a pad electrode while not adding a separate mask process or reducing a mask process. It relates to an organic light emitting display device and a manufacturing method thereof.

An organic light emitting display device (OLED) is a self-light emitting device and has low power consumption, high speed response speed, high luminous efficiency, high luminance, and wide viewing angle, and thus has attracted attention as a next-generation flat panel display device.

The organic light emitting display device (OLED) is divided into a top emission type and a bottom emission type according to a transmission direction of light emitted through the organic light emitting device. Since the bottom emission method has a problem of lowering the aperture ratio, the top emission method has recently been mainly used.

1 is a schematic cross-sectional view of a conventional top emission type organic light emitting display device.

A conventional top emission type organic light emitting display device includes a substrate 10, a thin film transistor T, a passivation layer 20, a planarization layer 30, a first electrode 40, an auxiliary electrode 50, and a bank 60. , an organic light emitting layer 70 and a second electrode 80.

Although not shown in the drawings, gate lines and data lines are provided on the substrate 10 to cross each other to define pixel areas, and thin film transistors (T) are provided in each pixel area.

The passivation layer 20 covers the thin film transistor T and is provided on the entire surface of the substrate 10 , and the planarization layer 30 covers the entire surface of the passivation layer 20 .

The first electrode 40 is provided on the planarization layer 30 and is electrically connected to the thin film transistor T. In this case, the first electrode 40 may include a material having high reflectivity, for example, a silver alloy layer.

The auxiliary electrode 50 is provided on the same layer as the first electrode 40 . The auxiliary electrode 50 is connected to the second electrode 80 and serves to lower the resistance of the second electrode 80 .

The bank 60 is provided at the boundary of each pixel area. The bank 60 is provided between the first electrode 40 and the auxiliary electrode 50 to insulate the first electrode 40 and the auxiliary electrode 50 . The organic emission layer 70 is provided on the first electrode 40 .

The second electrode 80 is provided on the entire surface of the substrate 10 and is connected to the auxiliary electrode 50 . The second electrode 80 may be made of a metallic material thinly formed to a thickness of several hundreds of angstroms or less.

In such a conventional top emission organic light emitting display device, since the thickness of the second electrode 80 is formed thin, resistance may be relatively high. In order to lower the resistance of the second electrode 80, the second electrode 80 and the auxiliary electrode 50 may be connected as described above, but the auxiliary electrode is on the same layer as the first electrode 40. Since the auxiliary electrode 50 must be provided, there is a spatial restriction in increasing the size of the auxiliary electrode 50. Accordingly, there is a limit to lowering the resistance of the second electrode 80 .

Also, although not shown in the drawing, when the source electrode 14 and the drain electrode 15 of the thin film transistor T are provided in the pixel area on the substrate 10, the pad area on the substrate 10 has a pad. Electrodes may be provided. However, since the pad electrode is vulnerable to corrosion, corrosion and metal migration may occur in the pad area as the subsequent process proceeds. A separate process for only the pad area may be added to prevent corrosion and metal transition in the pad area, but in this case, the productivity of the display device may decrease due to the additional process.

The present invention is to solve the above problems, and the present invention reduces the resistance of the second electrode and prevents corrosion and metal transition of the pad electrode while not adding a separate mask process or reducing the mask process. A technical problem is to provide a display device and a manufacturing method thereof.

In order to achieve the above object, in the organic light emitting diode display according to the present invention, an auxiliary wire is connected to the second electrode through an auxiliary electrode provided on the same layer as the first electrode, and the pad connection electrode connected to the pad is exposed to the outside. The pad cover electrode covers the top and side surfaces of the pad connection electrode so as not to In addition, the organic light emitting diode display according to the present invention includes a bank disposed along an edge of the first electrode.

According to embodiments of the present invention, an auxiliary wire connected to the auxiliary electrode is provided below the auxiliary electrode, and since the auxiliary wire is connected to the second electrode through the auxiliary electrode, resistance of the second electrode can be reduced. can

In addition, according to embodiments of the present invention, since a pad connection electrode is provided on the pad and a pad cover electrode is provided to cover the top and side surfaces of the pad connection electrode, corrosion in the pad electrode will not occur. and metal transition can be prevented accordingly. In addition, reliability and productivity of the organic light emitting display device may be improved without adding a separate mask process.

In addition, in the present invention, since the bank and the first electrode can be formed through the same single mask process, and the pad protection pattern and the protective film can be formed through the same single mask process, productivity can be improved and costs can be reduced. can

1 is a schematic cross-sectional view of a conventional top emission type organic light emitting display device.
2 is a cross-sectional view of an organic light emitting display device according to a first embodiment of the present invention.
3A to 3C are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a first embodiment of the present invention.
4 is a cross-sectional view of an organic light emitting display device according to a second exemplary embodiment of the present invention.
5A to 5G are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a second embodiment of the present invention.
6 is a cross-sectional view of an organic light emitting display device according to a third exemplary embodiment of the present invention.
7A to 7D are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a third exemplary embodiment of the present invention.
8 is a cross-sectional view of an organic light emitting display device according to a fourth exemplary embodiment of the present invention.
FIG. 9 is a plan view specifically illustrating the bank shown in FIG. 8 .
10A to 10F are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a fourth embodiment of the present invention.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only the present embodiments make the disclosure of the present invention complete, and common knowledge in the art to which the present invention belongs. It is provided to fully inform the holder of the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative, so the present invention is not limited to the details shown. Like reference numbers designate like elements throughout the specification. In addition, in describing the present invention, if it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. When 'includes', 'has', 'consists of', etc. mentioned in this specification is used, other parts may be added unless 'only' is used. In the case where a component is expressed in the singular, the case including the plural is included unless otherwise explicitly stated.

In interpreting the components, even if there is no separate explicit description, it is interpreted as including the error range.

In the case of a description of a positional relationship, for example, 'on top of', 'on top of', 'at the bottom of', 'next to', etc. Or, unless 'directly' is used, one or more other parts may be located between the two parts.

In the case of a description of a temporal relationship, for example, 'immediately' or 'directly' when a temporal precedence relationship is described in terms of 'after', 'following', 'next to', 'before', etc. It can also include non-continuous cases unless is used.

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

Each feature of the various embodiments of the present invention can be partially or entirely combined or combined with each other, technically various interlocking and driving are possible, and each embodiment can be implemented independently of each other or can be implemented together in a related relationship. may be

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

2 is a cross-sectional view of an organic light emitting display device according to a first embodiment of the present invention.

As can be seen from FIG. 2 , the organic light emitting diode display according to the first exemplary embodiment includes a pixel area AA and a pad area PA.

In the pixel area AA on the substrate 100, a thin film transistor T, a passivation layer 135, a planarization layer 145, a connection wire 161, an auxiliary wire 165, a protective layer 150, a first An electrode 171 , an auxiliary electrode 175 , a bank 180 , an organic emission layer 173 , and a second electrode 172 are provided.

The thin film transistor T includes an active layer 130 , a gate insulating layer 120 , a gate electrode 110 , an interlayer insulating layer 125 , a source electrode 141 and a drain electrode 142 .

The active layer 130 is provided on the substrate 100 to overlap the gate electrode 110 . The active layer 130 includes one end region 131 located on the side of the source electrode 141, the other end region 132 located on the side of the drain electrode 142, and one end region 131 and the other end region 133. It may consist of a central region 133 located in between. The central region 133 may be made of a semiconductor material not doped with a dopant, and the one end region 131 and the other end region 132 may be made of a semiconductor material doped with a dopant.

The gate insulating layer 120 is provided on the active layer 130 . The gate insulating layer 120 serves to insulate the active layer 130 from the gate electrode 110 . The gate insulating layer 120 covers the active layer 130 and is formed on the entire surface of the pixel area AA. The gate insulating layer 120 may be formed of an inorganic insulating material, such as silicon oxide (SiO _X ), silicon nitride (SiN _X ), or multiple layers thereof, but is not limited thereto.

The gate electrode 110 is provided on the gate insulating layer 120 . The gate electrode 110 is provided to overlap the central region 133 of the active layer 130 with the gate insulating layer 120 interposed therebetween. The gate electrode 110 is any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd) and copper (Cu) or It may be a single layer or multi-layer made of these alloys, but is not limited thereto.

The interlayer insulating layer 125 is provided on the gate electrode 110 . The interlayer insulating layer 125 is provided on the entire surface of the pixel area AA including the gate electrode 110 . The interlayer insulating layer 125 may be formed of the same inorganic insulating material as the gate insulating layer 120 , for example, silicon oxide (SiO _X ), silicon nitride (SiN _X ), or multiple layers thereof. However, it is not limited thereto.

The source electrode 141 and the drain electrode 142 are spaced apart from each other on the interlayer insulating layer 125 . The gate insulating film 120 and the interlayer insulating film 125 described above are provided with a first contact hole CH1 exposing a part of the region 131 at one end of the active layer 130, and at the other end of the active layer 130. A second contact hole CH2 exposing a part of the region 132 is provided. Accordingly, the source electrode 141 is connected to the one end region 131 of the active layer 130 through the first contact hole CH1, and the drain electrode 142 is connected to the second contact hole CH2. ) is connected to the other end region 132 of the active layer 130.

The source electrode 141 and the drain electrode 142 may be, for example, molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), or neodymium (Nd). ) and copper (Cu), or may be a single layer or a multi-layer made of any one of these alloys, but is not limited thereto.

The thin film transistor T configured as described above may be formed in each pixel area AA on the substrate 100 . The configuration of the thin film transistor (T) is not limited to the above-described example, and can be variously modified into a known configuration that can be easily implemented by those skilled in the art.

The passivation layer 135 is provided on the thin film transistor T. The passivation layer 135 is provided on the entire surface of the pixel area AA including the source electrode 141 and the drain electrode 142 . The passivation layer 135 serves to protect the thin film transistor T. The passivation layer 135 may be formed of an inorganic insulating material, for example, silicon oxide (SiO _X ) or silicon nitride (SiN _X ), but is not limited thereto.

The planarization layer 145 is provided on the passivation layer 135 . The planarization layer 145 performs a function of flattening the upper portion of the substrate 100 on which the thin film transistor T is provided. The planarization layer 145 may be, for example, acrylic resin, epoxy resin, phenolic resin, polyamides resin, polyimides resin, etc. It may consist of, but is not limited thereto.

A third contact hole CH3 exposing the drain electrode 142 is provided in the passivation layer 135 and the planarization layer 145 described above. The drain electrode 142 and the connection wire 161 are connected through the third contact hole CH3 .

The connection wire 161 is provided on the planarization layer 145 . The connection wire 161 serves to connect the drain electrode 142 and the first electrode 171 . The connection wire 161 may be, for example, molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu). It may be a single layer or multi-layer made of any one or alloy thereof, but is not limited thereto.

The auxiliary wire 165 is provided on the same layer as the connection wire 161 . The auxiliary wire 165 is provided to be spaced apart from the connection wire 161 . The auxiliary wire 165 may be simultaneously formed through the same process as the connection wire 161 and may be made of the same material. The auxiliary wire 165 is connected to the auxiliary electrode 175 .

The protective layer 150 covers upper portions of the connection wire 161 and the auxiliary wire 165 and is provided. The protective layer 150 includes a fourth contact hole CH4 exposing a portion of the connection wire 161 and a fifth contact hole CH5 exposing a portion of the auxiliary wire 165 . The protective layer 150 may be, for example, acrylic resin, epoxy resin, phenolic resin, polyamides resin, polyimide resin, etc. It may consist of, but is not limited thereto.

The first electrode 171 is provided on the protective layer 150 . The first electrode 171 is provided in the pixel area AA on the substrate 100 and is electrically connected to the thin film transistor T. The first electrode 171 is connected to the connection wire 161 exposed through the fourth contact hole CH4 . Since the connection wire 161 is connected to the drain electrode 142 , the first electrode 171 is connected to the drain electrode 142 through the connection wire 161 .

The first electrode 171 serves as an anode electrode or a cathode electrode according to the type of the thin film transistor T. In the present invention, the first electrode 171 serves as an anode of the organic light emitting device, and is a transparent conductive material having a relatively high work function value, for example, indium-tin-oxide (ITO) or indium-zinc- Oxide (IZO). In addition, the first electrode 171 may be composed of at least two or more layers including a metal material having excellent reflection efficiency, for example, aluminum (Al), silver (Ag), APC (Ag; Pb; Cu), etc. there is.

The auxiliary electrode 175 is provided on the same layer as the first electrode 171 . The auxiliary electrode 175 and the first electrode 171 are spaced apart from each other. The auxiliary electrode 175 is simultaneously formed through the same process as the first electrode 171 and may be made of the same material.

The auxiliary electrode 175 is connected to the auxiliary wire 165 exposed through the fifth contact hole CH5. As will be described later, the auxiliary electrode 175 is provided to contact the second electrode 172 in order to lower the resistance of the second electrode 172 . In addition, in order to lower the resistance of the second electrode 172, it is provided to be in contact with the above-described auxiliary wire 165.

The bank 180 is disposed between the first electrode 171 and the auxiliary electrode 175, and serves to insulate the first electrode 171 and the auxiliary electrode 175. The bank 180 may be formed of, for example, a transparent organic film or a black organic film such as polyimide resin, acryl resin, or benzocyclobutene (BCB), but is not limited thereto. .

The organic emission layer 173 is provided on the first electrode 171 . The organic emission layer 173 may have a hole transport layer/emission layer/electron transport layer structure or a hole injection layer/hole transport layer/emission layer/electron transport layer/electron injection layer structure. Furthermore, the organic light emitting layer 173 may further include at least one functional layer for improving light emitting efficiency and/or lifetime of the light emitting layer.

The second electrode 172 is provided to cover upper portions of the organic emission layer 173 and the bank 180 . The second electrode 172 extends to cover the bank 180 and is connected to the auxiliary electrode 175 .

When the first electrode 171 serves as an anode electrode, the second electrode 172 serves as a cathode electrode. A metallic material having a very thin thickness and a low work function may be used as the second electrode 172 . For example, the second electrode 172 is a metallic material such as silver (Ag), titanium (Ti), aluminum (Al), molybdenum (Mo), or an alloy of silver (Ag) and magnesium (Mg). can be used In addition, metallic materials as described above may be formed to a thickness of several hundred angstroms or less, for example, 200 angstroms or less, and used as the second electrode 172 . In this case, the second electrode 172 becomes a transflective layer and can be used as a substantially transparent cathode.

When the second electrode 172 is used as a transparent cathode, resistance may be relatively high because the thickness thereof is reduced. To lower the resistance of the second electrode 172, the second electrode 172 and the auxiliary electrode 175 are connected. However, since the auxiliary electrode 175 is provided on the same layer as the first electrode 171, space for providing the auxiliary electrode 175 is limited. That is, the larger the area of the auxiliary electrode 175 in contact with the second electrode 172 is, the more the resistance of the second electrode 172 can be reduced. However, since the auxiliary electrode 175 can be disposed only in an area where the first electrode 171 is not provided, there is a restriction in increasing the size of the auxiliary electrode 175, and thus the second electrode 172 There is a limit to lowering the resistance of

In the first embodiment of the present invention, in order to solve this problem, an auxiliary wire 165 connected to the auxiliary electrode 175 is provided below the auxiliary electrode 175 . Since the second electrode 172 is connected to the auxiliary electrode 175 and the auxiliary wire 165, compared to the related art in which the second electrode 172 and the auxiliary electrode 175 are connected, the second electrode 172 is connected to the auxiliary wire 165. Resistance of the electrode 172 may further decrease.

Although not shown in the drawing, a sealing portion may be additionally provided on the second electrode 172 . The sealing portion protects elements such as the organic light emitting element and the driving transistor T from external impact and prevents penetration of moisture.

A gate insulating layer 120 , an interlayer insulating layer 125 , a pad 240 , and a passivation layer 135 are provided in the pad area PA on the substrate 100 .

The gate insulating layer 120 extends from the pixel area AA and is provided on the entire surface of the pad area PA.

The interlayer insulating layer 125 is disposed on the gate insulating layer 120 , extends from the pixel area AA, and is provided on the entire surface of the pad area PA.

The pad 240 is located in the pad area PA and is provided on the interlayer insulating layer 125 . The pad 240 may be simultaneously formed through the same process as the source electrode 141 and the drain electrode 142 and may be made of the same material.

The passivation layer 135 extends from the pixel area AA and covers the entire surface of the pad area PA. However, a pad contact hole CHp exposing a part of the pad 240 is provided in the passivation layer 135 . A portion of the upper surface of the pad 240 may be exposed to the outside through the pad contact hole CHp.

In this case, the pad 240 may be corroded by an etching solution used in a photo mask process for forming the first electrode 171 . In addition, when the pad connection electrode 261 is exposed to the outside atmosphere, the pad 240 may be easily oxidized due to exposure to moisture in the air. Accordingly, corrosion and metal migration may occur in the pad area PA of the organic light emitting display device.

In order to prevent corrosion and metal transition of the pad area PA as described above, the pad contact hole CHp is formed by adding a separate process after the first electrode 171 is formed, or the clad ( Clad) or the like can be used to seal the pad connection electrode 261, but in this case, a photo mask process is added and productivity may decrease. Accordingly, in the second to fourth embodiments of the present invention to be described later, an organic light emitting diode display capable of preventing corrosion of the pad area PA without adding a photo mask will be described.

Hereinafter, the manufacturing method according to the first embodiment of the present invention will be described first in order to compare the number of masks, and then the second to fourth embodiments of the present invention and their manufacturing method will be described in detail.

3A to 3C are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a first embodiment of the present invention, which relates to the method of manufacturing the organic light emitting display device according to FIG. 2 described above. Therefore, the same reference numerals are assigned to the same components, and redundant descriptions of repetitive parts in the materials and structures of each component are omitted.

First, as shown in FIG. 3A , a thin film transistor T is formed in the pixel area AA on the substrate 100 and a pad 240 is formed in the pad area PA on the substrate 100 . The pad 240 is simultaneously formed through the same process as the source electrode 141 and the drain electrode 142 of the thin film transistor T. For convenience of description, a process of forming the pad 240, the source electrode 141, and the drain electrode 142 is referred to as a first mask process.

Next, as shown in FIG. 3B , a passivation layer 135 is formed on the entire surface of the pixel area AA including the thin film transistor T and the pad area PA including the pad 240 . The passivation layer 135 is formed to have a third contact hole CH3 exposing the drain electrode 142 of the thin film transistor T. Here, the entire surface of the pad area PA is covered by the passivation layer 135 . A process of forming the passivation layer 135 to have the third contact hole CH3 is referred to as a second mask process.

Next, a planarization layer 145 is formed on the passivation layer 135 positioned in the pixel area AA. In this case, the planarization layer 145 is not formed in the pad area PA. The planarization layer 145 is formed to have a third contact hole CH3 exposing the drain electrode 142 of the thin film transistor T. A process of forming the planarization layer 145 in the pixel area PA to have the third contact hole CH3 is referred to as a third mask process.

Next, a connection wire 161 connected to the thin film transistor T and an auxiliary wire 165 spaced apart from the connection wire 161 are formed on the planarization layer 145 . A process of forming the connection wire 161 and the auxiliary wire 165 is referred to as a fourth mask process.

Next, as shown in FIG. 3C , a passivation layer 150 is formed in the pixel area AA. In this case, the protective layer 150 is not formed in the pad area PA. The protective layer 150 is formed to have a fourth contact hole CH4 exposing the connection wire 161 and a fifth contact hole CH5 exposing the auxiliary wire 165 . A process of forming the protective layer 150 to have the fourth contact hole CH4 and the fifth contact hole CH5 is referred to as a fifth mask process.

Next, a first electrode 171 connected to the connection wire 161 and an auxiliary electrode 175 connected to the auxiliary wire 165 are formed on the protective layer 150 . The first electrode 171 and the auxiliary electrode 175 are spaced apart from each other. The process of forming the first electrode 171 and the auxiliary electrode 175 is referred to as a sixth mask process.

In order to form the first electrode 171 and the auxiliary electrode 175, a metal material, for example, ITO/Ag alloy/ITO is etched with an etching solution. Here, when the pad 240 is exposed to the outside, corrosion may occur on the pad 240 by the etching solution.

However, as in the first embodiment of the present invention, when the passivation layer 135 covers the entire surface of the pad 240, the passivation layer 135 protects the pad 240 from the etching solution. , Corrosion does not occur in the pad 240. However, in this case, as will be described later, a separate mask process for forming a pad contact hole CHp for exposing a part of the upper surface of the pad, that is, a seventh mask process is added.

Next, as described above, a pad contact hole CHp exposing a part of the upper surface of the pad 240 is formed in the passivation layer 135 provided in the pad area PA. A process of forming the pad contact hole CHp is referred to as a seventh mask process.

Next, a bank 180 for separating the first electrode 171 and the auxiliary electrode 175 is formed. The process of forming the bank 180 is referred to as an eighth mask process.

Finally, an organic emission layer 173 is formed on the first electrode 171 , and a second electrode 172 is formed on the organic emission layer 173 . In this case, the second electrode 172 extends along the bank 180 and is connected to the auxiliary electrode 175 .

As described above, in the first embodiment of the present invention, a total of eight photo masks are used from the process of forming the source electrode 141 and the drain electrode 172 to the process of forming the bank 180 .

4 is a cross-sectional view of an organic light emitting display device according to a second exemplary embodiment of the present invention. In the organic light emitting diode display according to the second embodiment of the present invention, a connection cover wire 192 is provided on the connection wire 161, and an auxiliary cover wire 190 is provided on the auxiliary wire 165. It is the same as the first embodiment of the present invention described above except that the pad connection electrode 261 and the pad cover electrode 290 are provided on the pad 240 . Therefore, the same reference numerals are assigned to the same components, and redundant descriptions of repetitive parts in the materials and structures of each component are omitted.

The thin film transistor T, the passivation layer 135, the planarization layer 145, the connection wiring 161, and the connection cover wiring 192 are formed in the pixel area AA on the substrate 100 according to the second embodiment of the present invention. , auxiliary wire 165, auxiliary cover wire 190, protective layer 150, first electrode 171, auxiliary electrode 175, bank 180, organic light emitting layer 173 and second electrode 172 is provided.

The connection cover wire 192 is provided on the connection wire 161 . The connection cover wire 192 is provided to cover the top and side surfaces of the connection wire 161 . In this case, the oxidation degree of the connection cover wire 192 may be lower than that of the connection wire 161, and thus the upper surface of the connection wire 161 is not easily corroded. The connection cover wire 192 may be formed of, for example, indium-tin-oxide (ITO) or indium-zinc-oxide (IZO).

The auxiliary cover wire 190 is provided on the same layer as the connection cover wire 192 . The auxiliary cover wire 190 and the connection cover wire 192 are spaced apart from each other. The auxiliary cover wire 190 is provided on the auxiliary wire 165 and is provided to cover the top and side surfaces of the auxiliary wire 165 .

The auxiliary cover wire 190 may be simultaneously formed through the same process as the connection cover wire 192 and may be made of the same material. Accordingly, the oxidation degree of the auxiliary cover wire 190 may be smaller than that of the auxiliary wire 165, and thus the upper surface of the auxiliary wire 165 is not easily corroded.

A gate insulating film 120, an interlayer insulating film 125, a pad 240, a passivation layer 135, a pad connection electrode 261, and a pad cover electrode 290 are provided in the pad area PA on the substrate 100. has been

The pad 240 is located in the pad area PA and is provided on the interlayer insulating layer 125 .

The passivation layer 135 extends from the pixel area AA and covers the entire surface of the pad area PA. However, a pad contact hole CHp exposing a part of the pad 240 is provided in the passivation layer 135 .

The pad connection electrode 261 is provided on the passivation layer 135 to overlap the pad 240 . The pad connection electrode 261 is connected to the pad 240 through the pad contact hole CHp. The pad connection electrode 261 may be simultaneously formed through the same process as the connection wire 161 and the auxiliary wire 165 and may be made of the same material.

The pad cover electrode 290 is provided on the pad connection electrode 261 . The pad cover electrode 290 covers side surfaces and upper surfaces of the pad connection electrode 261 so that the pad connection electrode 261 is not exposed to the outside. In addition, the pad cover electrode 290 covers a portion of the passivation layer 135 contacting the pad connection electrode 261 . Accordingly, the side surface and top surface of the pad connection electrode 261 may be completely sealed by the pad cover electrode 290 . The pad cover electrode 290 may be simultaneously formed through the same process as the auxiliary cover wire 190 and may be made of the same material.

According to the second embodiment of the present invention, since the pad cover electrode 290 is provided on the pad 240 to cover the pad 240, the generation by the etching solution used in the subsequent photo mask process Corrosion and metal migration of the pad area PA may be prevented. Accordingly, reliability of the organic light emitting display device may be improved.

5A to 5G are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a second embodiment of the present invention. Therefore, the same reference numerals are assigned to the same components, and redundant descriptions of repetitive parts in the materials and structures of each component are omitted.

First, as shown in FIG. 5A , source and drain electrodes 141 and 142 of the thin film transistor T are formed in the pixel area AA on the substrate 100 using a first mask process, and the substrate 100 ), the pad 240 is simultaneously formed in the pad area PA.

Next, a passivation layer 135 is formed on the entire surface of the pixel area AA including the thin film transistor T and the pad area PA including the pad 240 by using a second mask process. In this case, the passivation layer 135 is provided with a third contact hole CH3 exposing the drain electrode 142 of the thin film transistor T and a pad contact hole CHp exposing the pad 240. .

Next, as shown in FIG. 5B , a planarization layer 145 is formed on the passivation layer 135 positioned in the pixel area PA using the photoresist pattern PR formed through a third mask process. At this time, the third contact hole CH3 is formed to pass through the planarization layer 145 located in the pixel area AA excluding the pad area PA to expose the drain electrode 142 .

Meanwhile, in FIGS. 5A and 5B, the case where the pad contact hole (CHp) is formed in the second mask process and the planarization layer 145 is formed in the third mask process is described as an example, but in addition to this, FIGS. 5C and 5D show As described above, the planarization layer 145 may be formed in the second mask process and the pad contact hole CHp may be formed in the third mask process.

Specifically, as shown in FIG. 5C , a passivation layer 135 is formed on the entire surface of the substrate 100 to cover the source and drain electrodes 141 and 142 and the pad 240 formed through the first mask process.

Next, a planarization layer 145 is formed on the passivation layer 135 positioned in the pixel area PA by using a second mask process. In this case, a third contact hole CH3 exposing the drain electrode 142 is provided in the planarization layer 145 positioned in the pixel area AA excluding the pad area PA.

Next, as shown in FIG. 5D , the passivation layer 135 is patterned using the photoresist pattern PR formed through the third mask process. Accordingly, a pad contact hole CHp exposing the pad 240 is provided in the passivation layer, and the third contact hole CH3 is formed to penetrate the passivation layer 135 to expose the drain electrode 142 .

Meanwhile, while the formation of the passivation layer 135, the planarization layer 145, the third contact hole CH3, and the pad contact hole CHp have been described as being formed through two mask processes as an example, in addition to the halftone mask or slit It may also be formed through a single mask process using a mask.

Next, as shown in FIG. 5E , a connection wire 161 , an auxiliary wire 165 , and a pad connection electrode 261 are formed through a fourth mask process. In this case, the pad connection electrode 261 is connected to the pad 240 through the pad contact hole CHp.

Next, a connection cover wire 192 is formed to cover the connection wire 161 through a fifth mask process, and the auxiliary cover wire 190 is formed to cover the auxiliary wire 165 . In addition, a pad cover electrode 290 covering the pad connection electrode 261 is formed simultaneously with the connection cover wire 192 and the auxiliary cover wire 190 .

Next, a passivation layer 150 is formed in the pixel area AA and a pad protection pattern 152a is formed in the pad area PA by using a sixth mask process. In this case, the protective layer 150 and the pad protective pattern 152a may be formed using a halftone mask. The halftone mask is a mask having a light-blocking part, a light-transmitting part, and a semi-transmitting part, wherein the light-blocking part is a part that blocks light, the light-transmitting part is a part that transmits light, and the semi-light-transmitting part is a part that transmits light. It refers to the part that is smaller than the light emitter. When the halftone mask is used, patterns having different heights may be formed by differentially applying light amounts. Accordingly, the pad protection pattern 152a may be formed in the pad area PA, and the protective layer 150 may be formed in the pixel area AA.

Next, as shown in FIG. 5F, the first electrode 171 and the auxiliary electrode 175 are formed on the entire surface of the substrate 110 using a seventh mask process. In this case, in order to form the first electrode 171 and the auxiliary electrode 175, a metal material, for example, ITO/Ag alloy/ITO is etched with an etching solution, and the pad protection pattern 152a Since it covers the pad cover electrode 290, corrosion does not occur in the pad area PA.

Next, as can be seen in FIG. 5G , a bank 180 for distinguishing the first electrode 171 from the auxiliary electrode 175 is formed using an eighth mask process.

Finally, the pad protection pattern 152a provided in the pad area PA is removed, an organic light emitting layer 173 is formed on the first electrode 171, and a second organic light emitting layer 173 is formed on the organic light emitting layer 173. An electrode 172 is formed.

Meanwhile, although the removal of the pad protection pattern 152a after forming the bank has been described as an example, the pad protection pattern 152a is used as a mask when forming the first electrode 171. During the stripping process of the photoresist pattern, the photo It may also be removed simultaneously with the resist pattern. In this case, the pad protection pattern 152a is formed of a material that reacts to the strip liquid during the strip process, for example, photoresist.

As described above, in the second embodiment of the present invention, a total of eight photo masks are used from the process of forming the source electrode 141 and the drain electrode 172 to the process of forming the bank 180 . That is, compared to the first embodiment of the present invention, the pad connection electrode 261 is formed on the pad 240 using the same number of photo masks, and the pad cover electrode covers the pad connection electrode 261. It is possible to form (290). Accordingly, corrosion and metal transition in the pad area PA may be prevented without adding a separate mask, and reliability and productivity of the organic light emitting display device may be improved.

6 is a cross-sectional view of an organic light emitting display device according to a third exemplary embodiment of the present invention. In the organic light emitting diode display according to the third exemplary embodiment of the present invention, the protective layer 150 includes a first protective layer 151 and a second protective layer 152, and the first protective layer 151 and the connection wiring The connection cover wire 192 is provided between 161 and the auxiliary cover wire 195 is provided between the second protective layer 152 and the auxiliary wire 165. It is the same as Example 2. Therefore, the same reference numerals are assigned to the same components, and redundant descriptions of repetitive parts in the materials and structures of each component are omitted.

The thin film transistor T, the passivation layer 135, the planarization layer 145, the connection wiring 161, and the connection cover wiring 192 are formed in the pixel area AA on the substrate 100 according to the third embodiment of the present invention. , auxiliary wire 165, auxiliary cover wire 190, protective layer 150, first electrode 171, auxiliary electrode 175, bank 180, organic light emitting layer 173 and second electrode 172 is provided.

The connection cover wire 192 is provided on the connection wire 161 . The connection cover wire 192 is provided to cover the top and side surfaces of the connection wire 161 .

The auxiliary cover wire 190 is provided on the same layer as the connection cover wire 192 . The auxiliary cover wire 190 and the connection cover wire 192 are spaced apart from each other. The auxiliary cover wire 190 is provided on the auxiliary wire 165 and is provided to cover the top and side surfaces of the auxiliary wire 165 .

The protective layer 150 includes a first protective layer 151 and a second protective layer 152 .

The first protective layer 151 is provided on the connection cover wire 192 . The first protective layer 151 is provided to cover the upper surface of the connection cover wire 192 . In this case, the first protective layer 151 does not cover the side surface of the connection cover wire 192 . Accordingly, the side surface of the connection cover wire 192 may be provided to be exposed. This will be easily understood by referring to the manufacturing method described later.

The second protective layer 152 is provided on the auxiliary cover wire 190 . The second protective layer 152 is provided to cover the upper surface of the auxiliary cover wire 190 . In this case, the second protective layer 152 does not cover the side surface of the auxiliary cover wire 190 .

The first protective layer 151 and the second protective layer 152 are spaced apart from each other. As will be described later, a bank 180 is provided between the first protective layer 151 and the second protective layer 152 that are spaced apart from each other.

A first electrode 171 is provided on the first passivation layer 151 , and an auxiliary electrode 175 is provided on the second passivation layer 152 .

The bank 180 is provided between the first electrode 171 and the auxiliary electrode 175 to insulate the first electrode 171 and the auxiliary electrode 175 . In this case, the bank 180 is provided between the first protective layer 151 and the second protective layer 152 facing each other, and the connection cover wiring disposed under the first protective layer 151 192 and the auxiliary cover wire 190 disposed under the second protective layer 152 are insulated.

7A to 7D are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a third exemplary embodiment of the present invention. Therefore, the same reference numerals are assigned to the same components, and redundant descriptions of repetitive parts in the materials and structures of each component are omitted.

First, as shown in FIG. 7A , a thin film transistor T is formed in the pixel area AA on the substrate 100 using a first mask process, and a pad is formed in the pad area PA on the substrate 100. (240).

Next, a passivation layer 135 is formed on the entire surface of the pixel area AA including the thin film transistor T and the pad area PA including the pad 240 by using a second mask process. In this case, the passivation layer 135 is provided with a third contact hole CH3 exposing the drain electrode 142 of the thin film transistor T and a pad contact hole CHp exposing the pad 240. .

Next, a planarization layer 145 is formed on the passivation layer 135 positioned in the pixel area PA by using a third mask process.

Next, as can be seen in FIG. 7B, a connection wire 161, an auxiliary wire 165, and a pad connection electrode 261 are formed through a fourth mask process, and an auxiliary cover wire material 190a is applied to the entire surface of the substrate. do.

Next, by using a fifth mask process, a first passivation layer 151 and a second passivation layer 152 are formed in the pixel area AA to be spaced apart from the first passivation layer 151, and the pad area A pad protection pattern 152a is formed on (PA). Here, the fourth contact hole CH4 is provided in the first protective layer 151 , and the fifth contact hole CH5 is provided in the second protective layer 152 . The first protective layer 151, the second protective layer 152, and the pad protective pattern 152a may be formed using a halftone mask.

Next, as can be seen in FIG. 7C, the first electrode 171 is formed on the first protective layer 151 using a sixth mask process, and the auxiliary layer is formed on the second protective layer 152. An electrode 175 is formed. When the first electrode 171 and the auxiliary electrode 172 are formed, the cover wiring material 190a positioned in the pad area PA is simultaneously etched, and thus, the pad area PA has a pad. A cover electrode 290 is formed. In addition, when the first electrode 171 and the auxiliary electrode 172 are formed, the cover wiring material 190a located in the pixel area AA is etched simultaneously, and the connection cover in the pixel area AA is etched. A wire 192 and an auxiliary cover wire 195 are formed. Accordingly, the side surface of the connection cover wire 192 may be provided to be exposed to the outside. Since the connection cover wire 192 is made of a material with a low degree of oxidation, it is not easily corroded even when exposed to the outside.

Next, a bank 180 for separating the first electrode 171 and the auxiliary electrode 175 is formed by using a seventh mask process. In this case, the bank 180 is provided between the first protective layer 151 and the second protective layer 152 to insulate the connection cover wire 161 and the auxiliary cover wire 165 .

Finally, as shown in FIG. 7D , the pad protection pattern 152a is removed, an organic emission layer 173 is formed on the first electrode 171, and a second electrode is formed on the organic emission layer 173. (172).

As described above, in the third embodiment of the present invention, a total of seven photo masks are used from the process of forming the source electrode 141 and the drain electrode 172 to the process of forming the bank 180 . That is, in the third embodiment of the present invention, the pad connection electrode 261 is formed on the pad 240 using a smaller number of photo masks than in the first embodiment, and the pad connection electrode 261 It is possible to form the pad cover electrode 290 to cover the . Accordingly, corrosion and metal transition in the pad area PA may be prevented while reducing the number of masks.

FIG. 8 is a cross-sectional view of an organic light emitting display device according to a fourth exemplary embodiment of the present invention, and FIG. 9 is a plan view for explaining a bank shown in FIG. 8 in detail. The organic light emitting diode display according to the fourth embodiment of the present invention is the same as the second embodiment except that the bank 180 is formed along the edge of the first electrode 171 . Therefore, the same reference numerals have been assigned to the same components, and redundant descriptions of repetitive parts in the materials and structures of each component will be omitted.

The bank 180 shown in FIGS. 8 and 9 has an inner surface IS spaced a certain distance inward from the side surface of the first electrode 171 and a certain distance spaced outward from the side surface of the first electrode 171. It has an outer surface (OS). The bank 180 having an inner surface IS and an outer surface OS is formed to cover the top and side surfaces of the first electrode 180 except for the light emitting region where the organic light emitting layer 173 is formed. Accordingly, since the bank 180 is formed to cover the side surface of the first electrode 171 along the edge of the first electrode 171 excluding the light emitting area, the light emitting area has an open island shape.

10A to 10F are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a fourth embodiment of the present invention. Since the first to fifth mask processes in the manufacturing method of the organic light emitting diode display according to the fourth embodiment of the present invention are the same as those of the second embodiment of the present invention, detailed descriptions thereof will be omitted.

As shown in FIG. 10A , a protective layer 150 is formed in the pixel area AA using a sixth mask process, and a pad protection pattern 152a made of the same material as the protective layer 150 is formed in the pad area PA. ) to form At this time, the protective layer 150 is formed to have a fourth contact hole CH4 exposing the connection cover wiring 192 and a fifth contact hole CH5 exposing the auxiliary cover wiring 190 .

Next, as shown in FIG. 10B , a conductive material 171a and a photoresist film are sequentially formed on the substrate 100 on which the protective layer 150 and the pad protective pattern 152a are formed. In this case, the conductive material 171a has a multilayer structure in which a transparent conductive material, a metal material, and a transparent conductive material are sequentially stacked. For example, the conductive material 171a is formed of ITO/Ag alloy/ITO. The photoresist film is formed of, for example, photoacrylic (PAC).

Next, the photoresist layer is exposed and developed through a seventh mask process using a halftone mask or a slit mask, thereby forming a multi-layered photoresist layer pattern 180a having different first and second heights in the pixel area AA. The multi-layered photoresist pattern 180a is formed to have a first thickness in an area corresponding to the transflective portion of the halftone mask, and to have a second thickness thicker than the first thickness in an area corresponding to the light blocking portion of the halftone mask. In addition, since the photoresist layer is removed in the region corresponding to the transmissive portion of the halftone mask, the photoresist layer pattern 180a is not formed.

Next, as shown in FIG. 10C , the first electrode 171 and the auxiliary electrode 175 are formed by wet etching the conductive material 171a using the multi-layered photoresist pattern 180a as a mask. During this etching process, since the pad protection pattern 152a covers the pad cover electrode 290, corrosion of the pad cover electrode 290, the pad connection electrode 261, and the pad 240 located in the pad area PA is prevented. It can be prevented.

Next, as shown in FIG. 10D, the photoresist film pattern 180a is reflowed through a curing process, so that the photoresist film pattern 180a is formed of the exposed first electrode 171 and auxiliary electrode 175. It is formed to cover the side. Accordingly, it is possible to prevent the first electrode 171 from being electrically shorted with the second electrode 172 to be formed later.

Next, as shown in FIG. 10E, the photoresist pattern 180a and the pad protection pattern 152a are ashed or dry etched. Accordingly, the pad protection pattern 152a located in the pad area PA is removed to expose the pad cover electrode 290, and at the same time, the thickness of the photoresist film pattern 180a located in the pixel area AA is reduced to form a bank ( 180). The bank 180 is formed along an edge of each of the first electrode 171 and the auxiliary electrode 175 to cover side surfaces of the first electrode 171 and the auxiliary electrode 175 . At this time, the bank 180 exposes the light emitting region on the first electrode 171 and simultaneously exposes the upper surface of the auxiliary electrode 175 connected to the second electrode 172 .

Next, as shown in FIG. 10F, an organic light emitting layer 173 is formed on each light emitting region of the first electrode 171 exposed by the bank 180, and a second electrode ( 172) is formed. At this time, the second electrode 172 is electrically connected to the auxiliary electrode 175 to compensate for the resistance component of the second electrode 172 .

As described above, in the fourth embodiment of the present invention, a total of seven photo masks are used from the process of forming the source electrode 141 and the drain electrode 172 to the process of forming the bank 180 . That is, in the fourth embodiment of the present invention, a pad connection electrode 261 is formed on the pad 240 using a smaller number of photo masks than in the first embodiment, and the pad connection electrode 261 It is possible to form the pad cover electrode 290 to cover the . Accordingly, in the fourth embodiment of the present invention, it is possible to prevent corrosion and metal transition in the pad area PA while reducing the number of masks. Specifically, in the fourth embodiment of the present invention, since the pad cover electrode 290 can be protected during the etching process of the first electrode 171 by the pad protection pattern 152a formed simultaneously with the protective film 150, the pad Corrosion and fasting transition phenomena in the area PA may be prevented. In addition, in the fourth embodiment of the present invention, the bank 180 and the first electrode 171 can be formed through the same single mask process, and the pad protection pattern 152a and the protective film 150 can be formed using the same mask process. Since it can be formed through a process, productivity can be improved and costs can be reduced.

The above description is merely illustrative of the present invention, and various modifications may be made by those skilled in the art without departing from the technical spirit of the present invention. Therefore, the embodiments disclosed in the specification of the present invention are not intended to limit the present invention. The scope of the present invention should be construed by the claims below, and all techniques within the scope equivalent thereto should be construed as being included in the scope of the present invention.

100: substrate 145: passivation layer
151: first protective layer 152: second protective layer
161: connection wiring 165: auxiliary wiring
261: pad electrode 171: first electrode

Claims (15)

a substrate including a pixel region and a pad region;
a thin film transistor provided in a pixel area of the substrate;
a first electrode electrically connected to the thin film transistor through a connection wire;
a connection cover wire positioned on the connection wire to cover top and side surfaces of the connection wire;
an organic light emitting layer provided on the first electrode;
a second electrode provided on the organic light emitting layer;
an auxiliary electrode connected to the second electrode and provided on the same layer as the first electrode;
an auxiliary wire connected to the auxiliary electrode and provided under the auxiliary electrode;
an auxiliary cover wire positioned on the auxiliary wire to cover top and side surfaces of the auxiliary wire;
a pad provided on a pad area of the substrate;
a pad connection electrode connected to the pad on the pad; a pad cover electrode positioned on the pad connection electrode to cover top and side surfaces of the pad connection electrode;
a first protective layer positioned between the first electrode and the connection cover wire and exposing a side surface of the connection cover wire;
a second protective layer positioned between the auxiliary electrode and the auxiliary cover wire and exposing a side surface of the auxiliary cover wire; and
An organic light emitting display device comprising a bank disposed between the first protective layer and the second protective layer facing each other and covering the exposed side surface of the connection cover wire and the exposed side surface of the auxiliary cover wire. According to claim 1,
The oxidation degree of the pad cover electrode is lower than that of the pad connection electrode. According to claim 1,
The pad connection electrode is made of the same material as the auxiliary wire. According to claim 1,
The auxiliary cover wire is made of the same material as the pad cover electrode. According to claim 1,
The connection wire is provided on the same layer as the auxiliary wire. According to claim 1,
The first passivation layer and the second passivation layer are provided to be spaced apart from each other. delete delete According to claim 1,
The bank is further disposed along an edge of the first electrode. forming a thin film transistor in a pixel region on a substrate and forming a pad in a pad region on the substrate;
forming a planarization layer on the thin film transistor;
forming a connection wire connected to the thin film transistor and an auxiliary wire spaced apart from the connection wire on the planarization layer, and forming a pad connection electrode connected to the pad;
A connection cover wire is formed to cover the top and side surfaces of the connection wire, an auxiliary cover wire is formed to cover the top and side surfaces of the auxiliary wire, and a pad cover electrode is formed to cover the top and side surfaces of the pad connection electrode. doing;
forming a passivation layer on the pixel area and forming a pad protection pattern on the pad area;
forming a first electrode connected to the connection wire and an auxiliary electrode connected to the auxiliary wire on the protective layer;
forming a bank dividing the first electrode and the auxiliary electrode;
forming an organic light emitting layer on the first electrode; and
Forming a second electrode connected to the auxiliary electrode on the organic light emitting layer;
The pad protection pattern is removed after forming the bank or removed during a stripping process of the photoresist pattern used in forming the first electrode. delete According to claim 10,
The protective layer and the pad protective pattern are simultaneously formed of the same material. According to claim 12,
The step of forming a first electrode connected to the connection wire and an auxiliary electrode connected to the auxiliary wire on the protective layer,
stacking a conductive material on the substrate on which the protective layer and the pad protective pattern are formed;
forming a multi-layered photoresist film pattern on the substrate on which the conductive material is stacked;
and forming the first electrode and the auxiliary electrode by etching the conductive material using the photoresist pattern as a mask. According to claim 13,
Forming a bank dividing the first electrode and the auxiliary electrode is
and ashing the photoresist pattern and the pad protection pattern to form a bank disposed along an edge of the first electrode and simultaneously exposing the pad cover electrode. forming a thin film transistor in a pixel region on a substrate and forming a pad in a pad region on the substrate;
forming a planarization layer on the thin film transistor;
forming a connection wire connected to the thin film transistor and an auxiliary wire spaced apart from the connection wire on the planarization layer, forming a pad connection electrode connected to the pad, and applying an auxiliary cover material on the entire surface of the substrate;
forming a first passivation layer in the pixel area and a second passivation layer spaced apart from the first passivation layer, and forming a pad protection pattern on the pad area;
A first electrode is formed on the first passivation layer, an auxiliary electrode is formed on the second passivation layer, and the auxiliary cover material is etched when the first electrode and the auxiliary electrode are formed to form the connection wire. forming a connection cover wire covering top and side surfaces, an auxiliary cover wire covering top and side surfaces of the auxiliary wiring, and a pad cover electrode covering the top and side surfaces of the pad connection electrode;
forming a bank dividing the first electrode and the auxiliary electrode and removing the pad protection pattern;
forming an organic light emitting layer on the first electrode; and
Forming a second electrode connected to the auxiliary electrode on the organic light emitting layer;
The pad protection pattern is removed after forming the bank or removed during a stripping process of the photoresist pattern used in forming the first electrode,
The first protective layer is located between the first electrode and the connection cover wire and exposes a side surface of the connection cover wire,
The second protective layer is positioned between the auxiliary electrode and the auxiliary cover wire and exposes a side surface of the auxiliary cover wire,
The bank is positioned between the first protective layer and the second protective layer facing each other and covers the exposed side surface of the connection cover wire and the exposed side surface of the auxiliary cover wire. .

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