KR102141691B1 - Organic Light Emitting Diode Display Device and Method for Manufacturing The Same - Google Patents

Abstract

An organic light emitting display device according to an aspect of the present invention includes a first substrate and a second substrate facing each other; An organic light emitting device disposed on the first substrate and including a first electrode, a second electrode, and an organic emission layer positioned between the first electrode and the second electrode; And a color conversion layer disposed on the second substrate and including a color conversion member and a black matrix located between the color conversion members, wherein the black matrix has an upper surface with a width of a lower surface adjacent to the second substrate. It is characterized in that the tapered shape is smaller than the width of the.

Description

Organic Light Emitting Diode Display Device and Method for Manufacturing The Same

The present invention relates to an organic light emitting display device and a manufacturing method thereof, and more particularly, to an organic light emitting display device including a color conversion layer and a manufacturing method thereof.

As the information age matures, the market for display devices that display information is rapidly developing. Accordingly, research and development of the display device has been actively conducted, and particularly, a lightweight and thin flat panel display device has gained great popularity.

The flat panel display device includes a liquid crystal display (LCD), a plasma display panel (PDP), and an organic light emitting diode (OLED). Among them, an organic light emitting diode (OLED) is a remarkable growth in research and development.

In the organic light emitting display device, as the exciton transitions from the organic light emitting layer located between the two electrodes to the ground state, energy as much as the band gap of the organic material constituting the organic light emitting layer is emitted as light. Is displayed.

The organic light emitting display device includes an RGB-independent method in which organic substances that emit light of different colors for each pixel are independently deposited, and organic substances that emit white light are located in all pixels, and each color has a color conversion layer, so that each pixel has a different color. There is a WRGB method that emits light.

1 is a cross-sectional view showing a portion of a conventional WRGB organic light emitting display device 100.

As shown in FIG. 1, the organic light emitting display device 100 includes a first substrate 110, an organic light emitting device 120, an encapsulation layer 130, an adhesive layer 140, a color conversion layer 150, and 2 includes a substrate 160.

The organic light emitting device 120 and the encapsulation layer 130 are sequentially stacked on the first substrate 110, and the color including the color conversion member 151 and the black matrix 152 on the second substrate 160 The conversion layer 150 is located. The first substrate 110 and the second substrate 160 face each other and are bonded via the adhesive layer 140. That is, the adhesive layer 140 is positioned between the color conversion layer 150 and the encapsulation layer 130.

The color conversion member 151 may be formed while overlapping the black matrix 152 on the second substrate 160 on which the black matrix 152 is first formed, and the black matrix 152 is generally a color conversion member 151. The height is lower, and thus, the color conversion member 151 is formed to cover the black matrix 152 at a portion where the color conversion member 151 and the black matrix 152 overlap.

When the color conversion layer 150 is formed as described above, light emitted from the organic light emitting device 120 leaks to adjacent pixels before passing through the color conversion layer 150, resulting in lower luminance. However, there may be problems with gradation expression.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an organic light emitting display device capable of improving aperture ratio and luminance.

An organic light emitting display device according to an aspect of the present invention for achieving the above object includes a first substrate and a second substrate facing each other; An organic light emitting device disposed on the first substrate and including a first electrode, a second electrode, and an organic emission layer positioned between the first electrode and the second electrode; And a color conversion layer disposed on the second substrate and including a color conversion member and a black matrix located between the color conversion members, wherein the black matrix has a width of a lower surface adjacent to the second substrate having an upper surface. It is characterized by having a reverse taper shape smaller than the width.

A method of manufacturing an organic light emitting display device according to an aspect of the present invention for achieving the above object includes forming an organic light emitting device including a first electrode, an organic light emitting layer and a second electrode on a first substrate; Forming a color conversion layer including a reverse-tapered black matrix on a second substrate and a color conversion member positioned between the black matrix; Forming a reflective layer on the black matrix; And bonding the first substrate and the second substrate.

According to the present invention, it is possible to improve the aperture ratio by forming the black matrix of the color conversion layer in an inverted taper shape.

In addition, according to the present invention, the black matrix of the color conversion layer is formed higher than the color conversion member, thereby preventing light leakage between adjacent pixels.

In addition, according to the present invention, by arranging the reflective layer on the black matrix to prevent the absorption of light from the black matrix and by emitting light to the outside, there is an effect that can improve the luminance.

1 is a sectional view showing a conventional organic light emitting display device;
2 is a cross-sectional view showing an organic light emitting display device according to an embodiment of the present invention;
3 is a cross-sectional view showing an organic light emitting display device according to another embodiment of the present invention;
4 is an enlarged cross-sectional view of a pixel of an organic light emitting display device according to an exemplary embodiment of the present invention; And
5A to 5G are cross-sectional views showing a method of manufacturing an organic light emitting display device according to an embodiment of the present invention.

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

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

As shown in Figure 2, the organic light emitting display device according to an embodiment of the present invention, the first substrate 210, the organic light emitting device 220, the encapsulation layer 230, the light extraction layer 240, It includes an adhesive layer 250, a color conversion layer 260 and the second substrate 270.

The organic light emitting device 220 and the encapsulation layer 230 are positioned on the first substrate 210, and the light extraction layer 240 may be further positioned on the encapsulation layer 230. The color conversion layer 260 is positioned on the second substrate 270, and the color conversion layer 260 includes a black matrix 261 and a color conversion member 262. In addition, the color conversion layer 260 may further include a reflective layer 263 positioned on the black matrix 261.

The first substrate 210 and the second substrate 270 are bonded to each other and may be bonded through the adhesive layer 250.

First, the first substrate 210 and the second substrate 270 may include glass, metal, or plastic depending on the size or use of the organic light emitting display device. The plastic material can be implemented in various types of panels, including curved surfaces, and it is also possible to implement flexible panels.

The plastic material includes, for example, polyethersulphone (PES), polyacrylate (PAR), polyetherimide (PEI), polyethylene naphthalate (Polyethyelenen Napthalate; PEN), polyethylene terephthalide (Polyethyelene Terepthalate; PET), Polyphenylene Sulfide (PPS), Polyallylate, Polyimide (PI), Polycarbonate (PC), Triacetyl Cellulose (TAC) ), cellulose acetate propionate (CAP), and the like, and the first substrate 210 and the second substrate 270 may include at least one of glass, metal, and the plastic material.

The organic light emitting device 220 is positioned on the first substrate 210. The organic light emitting device 220 is a unit device in which the organic light emitting layer 223 emits light, and includes a first electrode 221, a bank layer 222, an organic light emitting layer 223, and a second electrode 224. The organic emission layer 223 is positioned between the first electrode 221 and the second electrode 224. A driving circuit (not shown) for driving the organic light emitting device 220 may be further disposed between the first substrate 210 and the organic light emitting device 220.

The first electrode 221 is positioned for each pixel area PA on the first substrate 210. The bank layer 222 overlaps the edge of the first electrode 221, divides the pixel area PA, and defines the light emitting area EA. The organic emission layer 223 is disposed on the bank layer 222, and the second electrode 224 is disposed on the organic emission layer 223.

The emission area EA is defined as an area in which the organic emission layer 223 contacts the first electrode 221 and the second electrode 224 or is an area in which the first electrode 221 is opened by the bank layer 222. Can be defined.

Meanwhile, holes are supplied from the first electrode 221, electrons are supplied from the second electrode 224, and the holes and electrons are the first electrode 221 and the organic light emitting layer 223. The second electrode 224 moves in the vertical direction. Accordingly, the emission area EA may be defined as an area in which the organic emission layer 223 contacts the first electrode 221 and also the second electrode 224. Alternatively, the emission region EA may be defined as a region in which the organic emission layer 223 overlaps the first electrode 221 and simultaneously overlaps the second electrode 224.

In addition, since the second electrode 224 is positioned above the first electrode 221, the area of the region in which the organic light emitting layer 223 contacts the second electrode 224 is the area of the region in contact with the first electrode 221. Since it is smaller than the area, the emission area EA may be defined as an area where the organic emission layer 223 contacts the second electrode 224. Alternatively, the emission area EA may be defined as an area where the organic emission layer 223 overlaps the second electrode 224.

The encapsulation layer 230 is positioned on the organic light emitting device 220. The encapsulation layer 230 may be a thin film encapsulation layer structure in which an organic material layer that covers and flattens foreign substances such as particles that may occur during the process and an inorganic material layer that prevents water infiltration are alternately stacked alternately. Alternatively, it may be a face seal structure.

The color conversion layer 260 is positioned on the second substrate 270. The color conversion layer 260 includes a black matrix 261 and a color conversion member 262 positioned on the second substrate 270. A color conversion member 262 corresponding to the emission area EA is positioned in each pixel area PA between the black matrices 261. That is, the black matrix 261 is positioned between the color conversion members 262. The area between the color conversion member 262 or the black matrix 261 may be defined as an opening area OA through which light emitted from the emission area EA is emitted.

The black matrix 261 is formed higher than the color conversion member 262 to prevent light from the light emitting area EA from leaking into the adjacent pixel area PA. The higher the height of the black matrix 261, the better the light leakage prevention effect.

Also, the black matrix 261 may be formed on the second substrate 270 in a reverse taper shape. When the black matrix 261 is formed in an inverse taper shape, the width of the lower surface of the black matrix 261 contacting or adjacent to the second substrate 270 becomes smaller than the width of the upper surface, and thus, in the organic light emitting device 220. The opening area OA, which is an emission area of emitted light, may be larger. That is, the aperture ratio of the organic light emitting display device can be improved.

On the other hand, the light emitting area EA may be smaller than the opening area OA. The light emitted from the light emitting area EA of a smaller area is emitted to the larger opening area OA, thereby improving the aperture ratio, increasing luminance, and reducing power consumption. However, the area of the light emitting area EA and the opening area OA is not limited to the above description.

The color conversion layer 260 may further include a reflective layer 263 positioned on the black matrix 261 to improve luminance. The reflective layer 263 may be formed of a material having a relatively high reflectivity, for example, a metal or a material containing a metal.

The reflective layer 263 may be positioned to surround only the side surface of the black matrix 261 as illustrated in FIG. 2 or to surround the side surface and top surface as illustrated in FIG. 3. The shape of the reflective layer 263 may vary depending on the forming process, and more details will be described when describing the manufacturing method.

The reflective layer 263 positioned on the side of the black matrix 261 reflects light emitted from the organic emission layer 223 toward the side of the black matrix 261 to the color conversion member 262. As described above, by reflecting light that can be absorbed and disappeared by the black matrix 261, luminance can be improved.

Although not shown in detail in the drawing, the reflective layer 263 positioned on the side surface of the black matrix 261 is thinner than other regions from a point adjacent to the color conversion member 262 to a point contacting the color conversion member 262. It may or may not contact the color conversion member 262. This does not directly help to improve the aperture ratio, but it can help to emit more light, which can be of some help in improving brightness.

An adhesive layer 250 for bonding the first substrate 210 and the second substrate 270 is positioned between the encapsulation layer 230 and the color conversion layer 260, and the adhesive layer 250 has an adhesive resin. It can be formed as.

A light extraction layer 240 may be further formed between the adhesive layer 250 and the encapsulation layer 230. The light extraction layer 240 may improve luminance by refracting and scattering light that may be extinguished by total reflection due to irregularities or patterns in the direction in which light emitted from the organic emission layer 223 is emitted. The light extraction layer 240 may refract and scatter light to cause a light leakage phenomenon, but the black matrix 261 having an inverse taper shape may be positioned at the boundary of the pixel area PA to prevent light leakage. Therefore, the inclination and height of the side surface of the black matrix 261 may be calculated to prevent light leakage.

In FIG. 2, the light extraction layer 240 is formed on the first substrate 210 and is shown to be positioned between the adhesive layer 250 and the encapsulation layer 230, but is not limited thereto, and on the second substrate 270 It may be formed on the color conversion layer 260 and the adhesive layer 250 may be formed between. When the light extraction layer 240 is formed on the color conversion layer 260 of the second substrate 270, the light leakage phenomenon that may be caused by the light extraction layer 240 is eliminated, so it may be more advantageous to improve luminance and prevent light leakage. have.

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

As illustrated in FIG. 3, the organic light emitting display device according to another exemplary embodiment of the present invention includes a reflective layer 263 surrounding side and top surfaces of the black matrix 261.

As shown in FIG. 2, when the reflective layer 263 is positioned only on the side surface of the black matrix 261, light directed toward the upper surface of the black matrix 261 may be absorbed by the black matrix 261 and extinguished. However, when the reflective layer 263 is also positioned on the upper surface of the black matrix 261, light toward the upper surface of the black matrix 261 is scattered by the light extraction layer 240 and then reflected by the reflective layer 263 to be a pixel area. (PA) You can head inside. In this case, light that can be extinguished can be recycled, which can help improve luminance.

4 is an enlarged cross-sectional view of a pixel area PA of an organic light emitting display device according to an exemplary embodiment of the present invention.

As illustrated in FIG. 4, light emitted from the organic light emitting layer 223 passes through the second electrode 224, the encapsulation layer 230, the light extraction layer 240, and the adhesive layer 250 in various directions. It is refracted and scattered, passes through the color conversion layer 260, is converted into light of a desired gray level, and then is emitted to the outside through the second substrate 270.

Light emitted from the organic emission layer 223 may pass through the second electrode 224 and the encapsulation layer 230, so that luminance and intensity may be weakened, but color does not disappear while passing through the light extraction layer 240. It may be scattered in the direction of the conversion member 262.

In addition, light directed toward the side of the black matrix 261 is also reflected from the reflective layer 263 in the direction of the color conversion member 262, which may help improve luminance.

Therefore, although the black matrix 261 is formed in an inverse taper shape, the area of the light emitting area EA is smaller than the area of the opening area OA, and while the scattering and reflection process is performed as described above, low consumption without deteriorating luminance The organic light emitting display device can be driven by electric power.

5A to 5G are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to an embodiment of the present invention.

First, as illustrated in FIG. 5A, the organic light emitting device 220, the encapsulation layer 230, and the light extraction layer 240 are sequentially formed on the first substrate 210. First, after forming the first electrode 221 for each pixel area PA, the bank layer 222 is formed to partially overlap the edge of the first electrode 221 to define the light emitting area EA. The organic emission layer 220 is formed by forming the organic emission layer 223 and the second electrode 224 on the first electrode 221 and the bank layer 222 in common with the pixel area PA.

Next, an organic layer (not shown) and an inorganic layer (not shown) are alternately stacked to form an encapsulation layer 230.

Next, the light extraction layer 240 is formed on the encapsulation layer 230. In order to form the unevenness, a laser may be transferred to the surface of the light extraction layer 240 to partially melt the surface of the light extraction layer 240 and then harden immediately. Alternatively, the layer formed on the top by double forming the light extraction layer 240 may finish the deposition process before forming a dense surface, and harden immediately to form irregularities.

Next, as shown in FIG. 5B, a photosensitive material is applied to form a black matrix 261 on the second substrate 270 to form a photosensitive layer 260a. The photosensitive layer 260a may use a negative photoresist. The negative photoresist is advantageous for forming a reverse tapered pattern by relatively etching the lower layer.

Next, as shown in FIG. 5C, the photosensitive layer 260a is patterned to form a black matrix 261. The shape of the black matrix 261 may be changed according to the etching time, but the longer the etching time, the lower the surface of the black matrix 261 exposed to the light source when exposed. Since it is more etched, an inverted tapered black matrix 261 can be formed.

Next, as illustrated in FIG. 5D, a color conversion member 262 is formed between the black matrices 261. A color conversion member 262 having a different color is formed for each pixel area PA, and the color conversion member 262 may be formed of a photosensitive material having various colors.

For example, when a red color conversion member 262 is formed in one pixel area PA, after applying a red photosensitive material to all pixel areas PA, exposure and Through the development process, only the red (red) photosensitive material is left in the corresponding pixel area PA to form the red color conversion member 262. The color conversion member 262 of other colors can also be formed in the same manner as above.

Next, as shown in Figure 5e, after applying the sacrificial pattern 260c on the color conversion layer 260 including the color conversion member 262 and the black matrix 261, the sacrificial pattern 260c and color A reflective material layer is formed by applying a reflective material to sufficiently cover the conversion layer 260. Inside the reflective material layer 260c, a crack is formed in an area corresponding to the edge region of the sacrificial pattern 260c, so that an etchant permeates between the cracks to allow a lift-off process. You can do it.

Next, as illustrated in FIG. 5F, by removing the sacrificial pattern 260c while simultaneously removing the reflective material layer 260c positioned on the sacrificial pattern 260c, the reflective layer 263 on the side of the black matrix 261 is removed. ). In this case, when the height becomes smaller as the sacrificial pattern 260c approaches the black matrix 261, the reflective layer 263 may be formed to surround or cover the side surface of the black matrix 261.

In the process of forming the reflective layer 263, when one of the black matrix 261 and the sacrificial pattern 260c is hydrophilic and the other is hydrophobic, when forming the sacrificial pattern 260c, sacrificial on the top surface of the black matrix 261 Since the pattern 260c is not formed, the reflective layer 263 may be formed on the top surface as well as the side surface of the black matrix 261. In this case, the reflective layer 263 may be formed to surround or cover the side and top surfaces of the black matrix 261.

Next, as shown in Figure 5g, the first substrate 210, the color conversion layer 260 and the reflection layer 263, the organic light emitting device 220, the encapsulation layer 230 and the light extraction layer 240 is formed The formed second substrate 270 is adhered by the adhesive layer 250.

The present invention can implement a larger opening area (OA) with a light emitting area (EA) of a small area by forming a reflective layer (263) on the black matrix (261) and the black matrix (261) formed in a reverse tapered shape as described above. Therefore, the aperture ratio is improved, and the reflective layer 263 is characterized by being capable of improving luminance and reducing power consumption.

Those skilled in the art to which the present invention pertains will appreciate that the above-described present invention can be implemented in other specific forms without changing its technical spirit or essential features.

Therefore, it should be understood that the above-described embodiments are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the following claims rather than the above detailed description, and it should be interpreted that all changes or modifications derived from the meaning and scope of the claims and equivalent concepts are included in the scope of the present invention. do.

210: first substrate 220: organic light emitting device
221: first electrode 222: bank layer
223: organic light emitting layer 224: second electrode
230: encapsulation layer 240: light extraction layer
250: adhesive layer 260: color conversion layer
261: black matrix 262: color conversion member
263: reflective layer 270: second substrate

Claims (14)

A first substrate and a second substrate facing each other;
An organic light emitting device disposed on the first substrate and including a first electrode, a second electrode, and an organic emission layer positioned between the first electrode and the second electrode;
A color conversion layer disposed on the second substrate and including a color conversion member and a black matrix located between the color conversion member;
A reflective layer surrounding side and top surfaces of the black matrix; And
Includes; between the organic light emitting device and the color conversion layer, the light extraction layer having an unevenness formed in a direction in which light emitted from the organic light emitting layer is emitted; includes,
The black matrix is an organic electroluminescent display device, characterized in that the width of the lower surface adjacent to the second substrate is smaller than the width of the upper surface. According to claim 1,
The height of the black matrix is greater than the height of the color conversion member organic light emitting display device. delete delete delete delete According to claim 1,
A plurality of pixel regions are defined on the first substrate and the second substrate,
The area of the area defined by the black matrix in any one of the plurality of pixel areas is larger than the area of the area where the organic light emitting layer overlaps the second electrode. According to claim 1,
A plurality of pixel regions are defined on the first substrate and the second substrate,
The area of the area where light is emitted from any one of the plurality of pixel areas is larger than the area of the area where the organic light emitting layer emits light. Forming an organic light emitting device including a first electrode, an organic emission layer, and a second electrode on the first substrate;
Forming a light extraction layer having irregularities formed in a direction in which light emitted from the organic light emitting layer is emitted on the organic light emitting device;
Forming a color conversion layer including a reverse-tapered black matrix on a second substrate and a color conversion member positioned between the black matrix;
Forming a reflective layer surrounding side and top surfaces of the black matrix; And
A method of manufacturing an organic light emitting display device comprising; bonding the first substrate and the second substrate. The method of claim 9,
Forming the color conversion layer,
Forming a photosensitive layer by applying a negative photosensitive material on the second substrate; And
Patterning the photosensitive layer to form the black matrix; further comprising a method for manufacturing an organic light emitting display device. The method of claim 9,
Forming the reflective layer,
Forming a sacrificial pattern on the color conversion layer;
Forming a reflective material layer by applying a reflective material on the sacrificial pattern; And
And forming the reflective layer on the black matrix by removing the sacrificial pattern and the reflective material layer positioned on the sacrificial pattern through a lift-off process. Way. The method of claim 11,
One of the sacrificial pattern and the black matrix is hydrophilic, and the other is a method of manufacturing an organic light emitting display device, characterized in that the hydrophobic. The method of claim 11,
The sacrificial pattern is a method of manufacturing an organic light emitting display device, characterized in that the smaller the height as the closer to the black matrix. delete

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