KR102165742B1 - A organic light emitting display device and the method thereof - Google Patents

Abstract

The present invention relates to an organic light emitting display device capable of etching an encapsulation layer without a metal mask using process while using inorganic films formed by an atomic layer deposition method as an encapsulation layer, and a manufacturing method thereof. According to the present invention, the organic light emitting display device includes: a substrate; a display part formed on the substrate and including an organic light emitting element; a pad electrode formed on the substrate at a predetermined distance from the display part; at least one encapsulation layer formed in a structure in which an organic film and an inorganic film are formed alternately on the substrate; a buffer layer formed on the encapsulation layer such that an upper part of the pad electrode is exposed, and protecting the encapsulation layer and improving adhesiveness; and a protection layer formed on the buffer layer to cover the buffer layer, and functioning as a mask for etching the inorganic film and the buffer layer in a lower part. The encapsulation layer has a structure which is an inorganic film of which the uppermost and lowermost layers are formed through an atomic layer deposition method, the organic film is formed limitedly in the inorganic film formation area while covering the entire area of the display part, and the inorganic film has a shape outwardly inclined from a part coming in contact with an end of the protection layer.

Description

Organic light emitting display device and manufacturing method {A ORGANIC LIGHT EMITTING DISPLAY DEVICE AND THE METHOD THEREOF}

The present invention relates to an organic light emitting display device and a manufacturing method, and more particularly, an organic light emitting display device capable of etching an encapsulation layer without a metal mask process while using inorganic films formed by an atomic layer deposition method as an encapsulation layer. And a manufacturing method.

An organic light-emitting display device is a display device using an organic light-emitting device containing a fluorescent organic compound that emits light when an electric current flows through it. Unlike a liquid crystal display (LCD), it can emit light itself and does not require a separate light source. , High contrast, wide viewing angle, and high-speed response are available, attracting recent attention. In addition, since the organic light emitting display device can be implemented in a thinner shape compared to an LCD, the application of a flexible display is being actively studied.

A conventional flexible organic light emitting display device has a structure in which a display unit 20 is formed on a substrate 10 made of a flexible glass, plastic, or metal thin film having flexible characteristics, as shown in FIG. A pad electrode 30 that is exposed to the outside and receives power from an external power source is formed in a non-display area outside the display unit 20.

In addition, a thin film transistor (TFT) that is specifically driven for each pixel is formed on the display unit 20, a first electrode connected to the thin film transistor, an organic light emitting layer formed on the first electrode, and formed on the organic light emitting layer. And an organic light emitting device comprising a second electrode.

Meanwhile, an encapsulation layer 40 is formed on the display unit 20 to protect the organic light-emitting device from external environments such as oxygen or moisture. In the case of a flexible organic light-emitting display device, a radius of curvature that is a measure of securing flexible characteristics In order to reduce, there is a trend that a laminate of the inorganic layers 42 and 46 and the organic layer 44 having excellent moisture permeability prevention properties while having a thin lamination thickness as the encapsulation layer 40 is used.

Therefore, as shown in FIG. 1, in order to contact the pad electrodes with the inorganic layers 42 and 46 formed by a method such as PECVD, the pad electrode 30 is formed by performing a deposition process using a metal mask 50 in general. The inorganic layers 42 and 26 are not deposited on the upper part.

In addition, in order to improve the barrier properties, a technique of using an aluminum oxide (Al ₂ O ₃ ) film as the inorganic film has been proposed, and the aluminum oxide (Al ₂ O ₃ ) films 42 and 46 are batch-type atomic layer deposition methods ( Film formation through Batch Type Atomic Layer Deposition) is preferred for process efficiency.

However, in the case of depositing an aluminum oxide (Al ₂ O ₃ ) film by the batch-type atomic layer deposition method, aluminum oxide (Al ₂ O ₃ ) is also deposited on the pad electrode in the non-display area, resulting in contact failure. A process of removing the aluminum oxide (Al ₂ O ₃ ) layer on the pad portion must be performed.

The technical problem to be solved of the present invention is to provide an organic light-emitting display device and a manufacturing method that are manufactured by etching the encapsulation layer without the use of a metal mask while using inorganic films formed by the atomic layer deposition method as encapsulation layers.

An organic light emitting display device according to the present invention for solving the above-described technical problem includes: a substrate; A display unit formed on the substrate and including an organic light emitting device; A pad electrode formed on the substrate to be spaced apart from the display unit by a predetermined distance; An encapsulation layer having at least one or more structures in which inorganic and organic layers are alternately formed on the substrate; A buffer layer formed on the encapsulation layer to expose an upper portion of the pad electrode, and to protect the encapsulation layer and improve adhesion; A protective layer formed on the buffer layer to cover the buffer layer and functioning as a mask for etching the lower buffer layer and the inorganic layer, wherein the encapsulation layer includes an inorganic layer in which the lowermost layer and the uppermost layer are formed using an atomic layer deposition method. It has a structure as a film, and the organic film is formed to be limited in the inorganic film formation region while covering the entire display portion, and the inorganic films of the plurality of layers have a continuous slope shape.

In the present invention, it is preferable that a blocking layer disposed outside the display unit is further provided on the substrate, and the organic layer is formed only inside the blocking layer forming region.

In addition, in the present invention, the inorganic layer is preferably an aluminum oxide (Al ₂ O ₃ ) layer.

In addition, in the present invention, it is preferable that the buffer layer is made of an inorganic material different from the inorganic layer.

In addition, in the present invention, the buffer layer is preferably made of a thickness of 100nm ~ 400nm.

In addition, in the present invention, the buffer layer is preferably any one of a silicon nitride film (SiN _x ), a silicon oxide film (SiO _x ), or a silicon oxynitride film (SiO _x N _y ).

In addition, in the present invention, the buffer layer preferably has a refractive index of 1.45 to 2.

In addition, in the present invention, the protective layer is preferably a second organic layer.

In addition, in the present invention, the protective layer may include an adhesive layer formed by being adhered to the buffer layer; It is preferable to include a base layer formed by bonding on the adhesive layer.

In addition, in the present invention, the base layer is preferably any one selected from a polarizing plate, a touch panel, a color filter, or a protective film.

In addition, in the present invention, it is preferable that the inclined surfaces of the buffer layer and the inorganic layers are continuous outward from a portion in contact with the end of the protective layer.

Meanwhile, the present invention includes the steps of 1) preparing a substrate on which a display unit including an organic light emitting device and a pad electrode are formed; 2) sequentially forming an encapsulation layer having at least one or more structures in which an inorganic film and an organic film for blocking oxygen and moisture are alternately formed on the substrate; 3) forming a buffer layer on the encapsulation layer to protect the encapsulation layer and improve adhesion; 4) forming a protective layer functioning as a mask for etching the lower buffer layer and the inorganic layer on a region of the upper surface of the buffer layer excluding an upper portion of the pad electrode; 5) etching and removing the buffer layer and the inorganic layer so as to have a shape inclined outward from a portion of the buffer layer and the inorganic layer in contact with the end of the protective layer, using the protective layer as a mask; It also provides a manufacturing method.

And in the present invention, the encapsulation layer is made of an inorganic film in which the lowermost layer and the uppermost layer are formed on the entire surface of the substrate using an atomic layer deposition method, and the organic film is formed limited in the inorganic film formation region while covering the entire display part. It is desirable.

In addition, in the method of manufacturing an organic light emitting display device according to the present invention, a blocking layer is further formed between the display unit and the pad electrode, the inorganic layer is deposited over the entire surface of the substrate, and the organic layer is formed of the blocking layer of the substrate. It is preferably formed only inside the formation region.

In addition, in the present invention, the buffer layer is preferably formed to a thickness of 100nm ~ 400nm.

In addition, in step 3) in the method for manufacturing an organic light emitting display device according to the present invention, it is preferable to form the buffer layer by a chemical vapor deposition method.

In addition, in the present invention, the protective layer may include an adhesive layer formed by being adhered to the buffer layer; It is preferable to include a base layer formed by bonding on the adhesive layer.

In addition, in the present invention, it is preferable that the protective layer is coated by a laminating method.

In addition, in step 5) in the present invention, it is preferable to remove the inorganic layers and the buffer layer formed on the pad electrode and the peripheral region thereof by a dry etching method.

In addition, in step 5) in the present invention, it is preferable to use a dry etching method of an Induced Coupled Plasma (ICP) method.

According to the organic light emitting display device and its manufacturing method of the present invention, the width of the bezel area can be significantly reduced to less than half compared to the conventional organic light emitting display device while maintaining the overall light transmittance high, and moisture and oxygen transmittance. There is also an advantage that can be significantly reduced.

1 is a diagram illustrating a structure and a manufacturing method of a conventional organic light emitting display device.
2 is a diagram illustrating a structure of an organic light emitting display device according to an exemplary embodiment of the present invention.
3 to 9 are flowcharts illustrating a method of manufacturing an organic light emitting display device according to an exemplary embodiment of the present invention.
10 to 12 are flowcharts illustrating a method of manufacturing an organic light emitting display device according to another exemplary embodiment of the present invention.

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

As shown in FIG. 2, the organic light emitting display device 100 according to the present embodiment includes a substrate 110, a display unit 120, a pad electrode 130, an encapsulation layer 140, a buffer layer 150, and a protective layer. It consists of 160, including.

First, the substrate 110 forms a basis on which other components may be installed, and is preferably made of a material having a flexible characteristic. Accordingly, the substrate 110 may be made of thin glass, plastic film, thin metal, or the like, and may be made of, for example, a plastic film such as polyimide.

Next, as shown in FIG. 2, the display unit 120 is a component formed on the substrate 110 and including an organic light emitting device. That is, the display unit 120 is formed in a matrix form on the substrate 110 to display an image, and specifically includes a thin film transistor (TFT) and an organic light emitting device. Here, since the specific structures of the thin film transistor and the organic light emitting device are substantially the same as those of the known structures, detailed descriptions thereof will be omitted.

Next, as shown in FIG. 2, the pad electrode 130 is a component formed in a non-display area on the substrate 110 by being spaced apart from the display unit 120 by a predetermined distance. That is, the pad electrode 130 is installed in a non-display area outside the display unit 120 and has a structure in which the upper surface thereof is exposed to be connected to an external power source.

Next, the encapsulation layer 140 has a structure in which at least one layer is formed in which an inorganic layer and an organic layer are alternately formed on the substrate 110 as shown in FIG. 2, and the display unit 120 It is a component that encapsulates ). That is, the encapsulation layer 140 is formed to cover the display unit 120 to seal the display unit 120 so that it is not exposed to external moisture and oxygen.

To this end, in this embodiment, the encapsulation layer 140 is formed in a structure in which the inorganic layer 142 and the organic layer 144 are alternately formed as shown in FIG. 2 to achieve an effective encapsulation effect. At this time, it is preferable that the lowermost layer and the uppermost layer of the encapsulation layer 140 are made of an inorganic film.

In addition, in the present embodiment, the organic layer 144 is formed to be limited in the area where the inorganic layer 142 is formed while covering the entire display unit 120 as shown in FIG. 2. Accordingly, the organic layer 144 also has a structure that is not exposed to external air.

In addition, the inorganic layers 142 and 146 are formed wider than the organic layer 144 to completely cover the display unit 120 and the organic layer 144 on the substrate 110, as shown in FIG. It is preferable to have a shape inclined outward from the portion in contact with the end of the protective layer 160. When the ends of the inorganic layers 142 and 146 of the plurality of layers have a continuous inclined surface structure, penetration of moisture and oxygen between each inorganic layer or between the inorganic layer and the substrate becomes more difficult, which is preferable.

In particular, when the blocking layer 170 is further formed in the organic light emitting display device 100 according to the present embodiment as shown in FIG. 2, the inorganic layers 142 and 146 are formed of the blocking layer 170. Inorganic layers are formed to the outside of the blocking layer 170 forming area to completely cover the barrier layer 170. On the other hand, it is preferable that the organic layer 144 is formed only inside the area where the blocking layer 170 is formed.

Meanwhile, in the present embodiment, the inorganic films 142 and 146 are preferably inorganic films formed using an atomic layer deposition method, since they can most reliably block external moisture and oxygen. For example, the inorganic layers 142 and 146 may be formed of an aluminum oxide (Al ₂ O ₃ ) layer.

Next, the buffer layer 150 is formed so that the upper portion of the pad electrode 130 is exposed on the encapsulation layer 140, as shown in FIG. 2, protects the encapsulation layer 140 and improves adhesion. It is a component to make. That is, the buffer layer 150 improves adhesion between the inorganic layer 146 and the adhesive layer 162, which is the uppermost layer of the encapsulation layer 140, and at the same time, the pressure applied in the process of forming the protective layer 160 It absorbs and protects the inorganic layers 142 and 146 by minimizing the impact received.

Meanwhile, in this embodiment, since the buffer layer 150 is a layer through which light emitted from the display unit 120 transmits, it is preferable that the buffer layer 150 is made of a material having excellent transmittance and refractive index, and the refractive index of the buffer layer 150 is It is preferably 1.45-2.

To this end, in the present embodiment, the buffer layer 150 is formed of an inorganic material different from the inorganic layers 142 and 146, for example, a silicon nitride film (SiN _x ), a silicon oxide film (SiO _x ), or a silicon oxynitride film (SiO _It can be made of any one of _x N _y ).

And in this embodiment, the buffer layer 150 is preferably made of a thickness of 100nm ~ 400nm, if less than 100nm, there is a problem that the encapsulation layer 140 is not sufficiently protected, and if it exceeds 400nm, the transmittance is lowered. There is a problem.

Next, the protective layer 160 is formed on the buffer layer 150 to cover the buffer layer 150, as shown in FIG. 2, and functions as a mask for etching the lower buffer layer 150 and the inorganic layer. It is a component that does. Therefore, the protective layer 160 may be made of a material that is not etched in a dry etching process, and may be formed of a second organic layer different from the organic layer 144.

In addition, since the area where the protective layer 160 is formed is the same as the area in which the inorganic layers 142 and 146 are formed, as shown in FIG. 2, it is outside the blocking layer 170 and the pad electrode 130 ) Is formed not to cover.

Meanwhile, in the present embodiment, the protective layer 160 may be formed of an adhesive layer 162 and a base layer 164 as shown in FIG. 2. Here, the adhesive layer 162 is a component that adheres the base layer 164 to the buffer layer 150, and the base layer 164 is a component that is formed by being adhered to the adhesive layer 162, It performs the mask function.

Therefore, the base layer 164 is preferably any one selected from a polarizing plate, a touch panel, a color filter, or a protective film, as it is a component to be installed in the organic light emitting display device 100 and can also perform a mask function. .

Hereinafter, a method of manufacturing an organic light emitting display device according to the present embodiment will be described with reference to the drawings.

First, as shown in FIG. 3, a step (S100) of preparing the substrate 110 on which the display unit 120 including the organic light emitting device and the pad electrode 130 are formed is performed. A detailed method of forming a display unit and a method of forming a pad electrode performed in this step S100 are substantially the same as those previously known, so a detailed description thereof will be omitted.

Next, as shown in FIGS. 4 to 6, at least one or more layers of the structure in which inorganic layers 142A and 146A for blocking oxygen and moisture and organic layers 144 are alternately formed on the substrate 110 The step (S200) of sequentially forming an encapsulation layer formed as a result proceeds. Therefore, this step (S200) is divided into sub-steps of forming a first inorganic layer, forming an organic layer, and forming a second inorganic layer.

First, as shown in FIG. 4, a first inorganic layer 142A is formed on the substrate 110 to cover the entire display unit 120 and the pad electrode 130 by using an atomic layer deposition method. In this case, as described above, the first inorganic layer 142A is preferably an aluminum oxide (Al ₂ O ₃ ) layer.

In addition, as shown in FIG. 5, the organic layer 144 is formed so as to be confined within the region where the first inorganic layer 142 is formed while covering the entire display unit 120. A specific method of forming the organic layer 144 may use a method such as inkjet.

Next, as shown in FIG. 6, a step of forming a second inorganic layer 146A entirely on the substrate 110 on which the organic layer 144 is formed is performed. A specific method of forming the second inorganic layer 146A is the same as the method of forming the first inorganic layer 142A.

Next, as shown in FIG. 7, a step S300 of forming a buffer layer 150A that protects the encapsulation layer and improves adhesiveness on the encapsulation layer 140A is performed. As described above, the buffer layer 150A is preferably any one of a silicon nitride film (SiN _x ), a silicon oxide film (SiO _x ) or a silicon oxynitride film (SiO _x N _y ), and chemical vapor deposition (Chemical Vapor Deposition) Formed in a way.

And in this embodiment, the buffer layer 150A is preferably formed to have a thickness of 100 nm to 400 nm, and when it has a thickness of less than 100 nm, the inorganic layers 142A and 146A cannot be sufficiently protected, and when it exceeds 400 nm There is a problem in that the transmittance is inferior.

Next, as shown in FIG. 8, a protective layer serving as a mask for etching the lower buffer layer 150A and the inorganic layers 142A and 146A on the upper surface of the buffer layer 150A excluding the upper portion of the pad electrode 130 ( 160) is formed (S400). Since the protective layer 160 functions as a mask in the etching of the buffer layer 150A and the inorganic layers 142A and 146A, the portion where the buffer layer 150A and the inorganic layers 142A and 146A are removed during the etching process, that is, It is formed on a portion other than the upper surface of the pad electrode 130.

Specifically, the protective layer 160 may be formed of an adhesive layer 162 and a base layer 164 adhered thereto, as shown in FIG. 8, and the base layer 164 is, as described above, It is preferable that it is any one selected from a polarizing plate, a touch panel, a color filter, or a protective film.

Therefore, the protective layer 160 in the form of a film is specifically formed by being coated with a laminating method. In this process, pressure is applied to the inorganic layers 142A and 146A, and the buffer layer 150A absorbs pressure and impact to prevent damage to the inorganic layers 142A and 146A by this pressure. .

Next, as shown in FIG. 9, using the protective layer 160 as a mask, the inorganic layers 142A and 146A may have a shape inclined outward from the portion in contact with the end of the protective layer 160. A step (S500) of etching and removing the buffer layer 150A and the inorganic layers 142A and 146A is performed. In this step (S500), the inorganic layers 142A and 146A and the buffer layer 150A formed on the pad electrode 130 and the surrounding region are removed by a dry etching method. Specifically, ICP (Induced Coupled Plasma) is removed. ) It is preferable to use the dry etching method.

At this time, the side ends of the buffer layer 150 and the inorganic layers 142 and 146 remaining after being removed by etching are formed as continuous inclined surfaces as shown in FIG. 9.

Meanwhile, as shown in FIG. 10, a blocking layer 170 may be further formed between the display unit 120 and the pad electrode 130. Two or more blocking layers 170 may be formed. When the blocking layer 170 is further formed in this way, as shown in FIG. 11, the area in which the organic layer 144 is formed is limited within the blocking layer 170.

In addition, the other steps are performed in the same manner, and as shown in FIG. 12, the area where the protective layer 160 is formed is formed to cover the outside of the blocking layer 170. In addition, when etching is performed using the protective layer 160 as a mask, as shown in FIG. 2, the ends of the buffer layer 150 and the inorganic layers 142 and 146 cover the outer region of the blocking layer 170. Is formed to be

100: organic light emitting display device according to an embodiment of the present invention
110: substrate 120: display
130: pad electrode 140: encapsulation layer
150: buffer layer 160: protective layer
170: blocking layer

Claims (23)

Board;
A display unit formed on the substrate and including an organic light emitting device;
A pad electrode formed on the substrate to be spaced apart from the display unit by a predetermined distance;
An encapsulation layer having at least one or more structures in which inorganic and organic layers are alternately formed on the substrate;
A buffer layer formed on the encapsulation layer to expose an upper portion of the pad electrode, and to protect the encapsulation layer and improve adhesion;
And a protective layer formed on the buffer layer to cover the buffer layer and functioning as a mask for etching the lower buffer layer and the inorganic layer; and
The encapsulation layer has a structure in which the lowermost layer and the uppermost layer are inorganic films formed using an atomic layer deposition method,
The organic layer is formed to be limited in the inorganic layer formation region while covering the entire display portion,
The inorganic layer has a shape inclined outward from a portion in contact with an end of the protective layer. The method of claim 1,
An organic light-emitting display device, wherein a blocking layer disposed outside the display unit is further provided on the substrate, and the organic layer is formed only inside the blocking layer forming region. The method of claim 1, wherein the inorganic film,
An organic light emitting display device comprising an aluminum oxide (Al ₂ O ₃ ) layer. The method of claim 1, wherein the buffer layer,
An organic light emitting display device comprising an inorganic material different from the inorganic layer. The method of claim 4, wherein the buffer layer,
An organic light emitting display device comprising a thickness of 100 nm to 400 nm. The method of claim 4, wherein the buffer layer,
An organic light emitting display device comprising any one of a silicon nitride film (SiN _x ), a silicon oxide film (SiO _x ), or a silicon oxynitride film (SiO _x N _y ). The method of claim 4, wherein the buffer layer,
The organic light emitting display device, characterized in that the refractive index (Refractive Index) is 1.45 ~ 2. The method of claim 1, wherein the protective layer,
An organic light emitting display device comprising a second organic layer. The method of claim 1, wherein the protective layer,
An adhesive layer formed by adhering to the buffer layer;
And a base layer formed by being adhered to the adhesive layer. The method of claim 9, wherein the base layer,
An organic light emitting display device comprising any one selected from a polarizing plate, a touch panel, a color filter, or a protective film. The method of claim 1,
The organic light emitting display device, wherein the inorganic layers have a continuous shape. 1) preparing a substrate on which a display unit including an organic light-emitting device and a pad electrode are formed;
2) sequentially forming an encapsulation layer having at least one or more structures in which an inorganic film and an organic film for blocking oxygen and moisture are alternately formed on the substrate;
3) forming a buffer layer on the encapsulation layer to protect the encapsulation layer and improve adhesion;
4) forming a protective layer functioning as a mask for etching the lower buffer layer and the inorganic layer on a region of the upper surface of the buffer layer excluding an upper portion of the pad electrode;
5) etching and removing the buffer layer and the inorganic layer so as to have a shape inclined outward from the portion of the inorganic layer in contact with the end of the protective layer using the protective layer as a mask; and a method for manufacturing an organic light emitting display device comprising: . The method of claim 12, wherein the encapsulation layer,
Fabrication of an organic light-emitting display device, characterized in that the lowermost layer and the uppermost layer are formed of an inorganic film formed on the entire surface of the substrate using an atomic layer deposition method, and the organic film is formed to be limited within the inorganic film formation region while covering the entire display part. Way. The method of claim 13,
A blocking layer is further formed between the display unit and the pad electrode,
The inorganic layer is formed by depositing over the entire surface of the substrate, and the organic layer is formed only inside the blocking layer forming region of the substrate. The method of claim 13, wherein the inorganic film,
An organic light emitting display device manufacturing method comprising an aluminum oxide (Al ₂ O ₃ ) layer. The method of claim 12, wherein the buffer layer,
A method of manufacturing an organic light emitting display device, comprising any one of a silicon nitride film (SiN _x ), a silicon oxide film (SiO _x ), or a silicon oxynitride film (SiO _x N _y ). The method of claim 12, wherein the buffer layer,
Method for manufacturing an organic light emitting display device, characterized in that formed to a thickness of 100nm ~ 400nm. The method of claim 16, wherein in step 3),
A method of manufacturing an organic light-emitting display device, comprising forming the buffer layer by a chemical vapor deposition method. The method of claim 13, wherein the protective layer,
An adhesive layer formed by adhering to the buffer layer;
And a base layer formed by being adhered to the adhesive layer. The method of claim 19, wherein the base layer,
A method of manufacturing an organic light emitting display device, characterized in that it is any one selected from a polarizing plate, a touch panel, a color filter, or a protective film. The method of claim 19, wherein the protective layer,
A method of manufacturing an organic light-emitting display device, characterized in that it is coated by a laminating method. The method of claim 12, wherein in step 5),
A method of manufacturing an organic light-emitting display device, comprising removing the inorganic layers and the buffer layer formed on the pad electrode and a peripheral region thereof by a dry etching method. The method of claim 22, wherein in step 5),
A method of manufacturing an organic light emitting display device, characterized in that a dry etching method of an Induced Coupled Plasma (ICP) method is used.

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