KR102047413B1 - 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 defined by a plurality of pixels; An anode formed on the first substrate; A bank layer formed to overlap an edge region of the anode electrode and defining a light emitting region of each pixel; An organic emission layer formed on the anode; A cathode electrode formed on the organic light emitting layer; A color refiner formed for each pixel on the second substrate and overlapping each other; And a black matrix formed in an area where the color refiner overlaps, wherein the first substrate and the second substrate are joined to face each other such that the black matrix and the bank correspond to each other.

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 active organic light emitting display device and a manufacturing method thereof.

Disadvantages of the first display devices, represented by cathode ray tubes, were large volume and heavy weight. Since the development of flat panel displays, flat panel displays have become the mainstream of display devices. Compared to the cathode ray tube, which has a high image quality, the flat panel display device has become popular in the display market because it is possible to realize a lightweight and thin display.

Flat panel display devices include liquid crystal displays (LCDs), plasma display panels (PDPs), organic light emitting diode displays (OLEDs), and the like. Devices have been developed the most among flat panel display devices, and organic light emitting display devices have been spotlighted as next generation flat panel display devices after liquid crystal display devices. In particular, the organic light emitting display device is a self-luminous device, and it is possible to implement a lighter and thinner device than a liquid crystal display device that emits light through a backlight.

The organic light emitting display device as described above is classified into a top emission type and a bottom emission type according to the light emission direction. In addition, the organic light emitting display device uses a color refiner, which is a kind of color converting member disposed separately of red, green, and blue for each pixel as an organic light emitting layer that emits white light as a light source. WRGB method that converts white light into a desired color and emits color, and does not have color refiner, and emits white light to realize full color, and RGB method that independently arranges red light emitting layer, green light emitting layer and blue light emitting layer in each pixel Can be divided largely into

In the WRGB method, the organic light emitting display device to which the top emission method is applied requires a certain distance for the light emitted from the organic light emitting layer to reach the color refiner. This is because there is a structure that must be formed on the organic light emitting layer. First, a transparent electrode is present on the organic light emitting layer. The transparent electrode here may preferably be a cathode electrode. In addition, an encapsulation layer may be formed between the color refiner and the transparent electrode for the purpose of preventing damage to the organic light emitting layer, or an internal filler or an adhesive material may be positioned between the color refiner and the cathode electrode. The encapsulation layer, the internal filling material or the adhesive material should be formed to have a predetermined thickness or more for sealing the organic light emitting display device. Because of the above structure, a constant gap is required between the organic light emitting layer and the color refiner, and this gap is called a cell gap. Usually, the cell gap is defined as the gap between the color refiner and the organic light emitting layer, and sometimes may be defined as the gap between the color refiner and the transparent electrode. The cell gap may cause light leakage between adjacent pixels.

1 is a cross-sectional view illustrating a part of a general organic light emitting display device to which a top emission method is applied among WRGB methods.

As shown in FIG. 1, in the WRGB method, a general organic light emitting display device to which a top emission method is applied includes a first substrate 101, a second substrate 102, an anode electrode 110, a bank layer B, The organic light emitting layer 120 includes a cathode electrode 130, a black matrix BM, and a color refiner 140.

An anode electrode 110, a bank layer B, an organic emission layer 120, and a cathode electrode 130 are sequentially formed on the first substrate 101. An encapsulation layer (not shown) may be further formed on the cathode electrode 130 to prevent damage to the organic light emitting layer 120.

The color refiner 140 is formed on the second substrate 102 in the pixel defined by the black matrix BM and the black matrix BM.

The first substrate 101 and the second substrate 102 are joined to face each other. An adhesive material or organic filler may be interposed between the first substrate 101 and the second substrate 102 to assist the bonding of the first substrate 101 and the second substrate 102. In this case, the cell gap may be about several tens of μm, and light leakage between pixels adjacent to white light L1 emitted from one pixel may occur through the cell gap. In addition, as the cell gap increases, light leakage between pixels may become more severe.

As shown, depending on the viewing angle, white light L1 from one pixel may appear to come from an adjacent pixel. As such, when light leakage occurs, accurate gradation representation of each pixel may be difficult, and distortion of gradation representation may occur. Furthermore, when the high resolution organic light emitting display device is implemented, the light leakage phenomenon may become more severe because the width of the pixel becomes smaller.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to provide an organic light emitting display device capable of preventing light leakage between pixels.

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 defined by a plurality of pixels; An anode formed on the first substrate; A bank layer formed to overlap an edge region of the anode electrode and defining a light emitting region of each pixel; An organic emission layer formed on the anode; A cathode electrode formed on the organic light emitting layer; A color refiner formed for each pixel on the second substrate and overlapping each other; And a black matrix formed in an area where the color refiner overlaps, wherein the first substrate and the second substrate are joined to face each other such that the black matrix and the bank correspond to each other.

According to an aspect of the present invention, there is provided a method of manufacturing an organic light emitting display device, including: forming an anode electrode on a first substrate defined by a plurality of pixels; Forming a bank layer to overlap an edge region of the anode electrode; Forming an organic emission layer on the anode; Forming a cathode on the organic light emitting layer; Forming a color refiner overlapping each other for each pixel on a second substrate defined by a plurality of pixels; Forming a black matrix in the overlapped area of the color refiner; And bonding the first substrate and the second substrate to face each other such that the bank layer and the black matrix correspond to each other.

According to the present invention, it is possible to prevent light leakage between pixels by overlapping the color refiners of adjacent pixels and forming a black matrix on the overlapped color refiners.

In addition, according to the present invention, it is possible to prevent light leakage between pixels, thereby enabling accurate gradation representation in each pixel.

In addition, according to the present invention, by preventing the light leakage between pixels, there is an effect that can implement a high-resolution organic light emitting display device.

1 is a cross-sectional view showing a general organic light emitting display device;
2 is a cross-sectional view illustrating an organic light emitting display device according to an embodiment of the present invention;
3 is a cross-sectional view showing a second substrate on which color refiners overlap in a first direction;
4 is a cross-sectional view showing a second substrate on which color refiners overlap in a second direction; And
5A through 5C are cross-sectional views illustrating 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 illustrating an organic light emitting display device according to an embodiment of the present invention.

As shown in FIG. 2, the organic light emitting display device according to the exemplary embodiment of the present invention may include a first substrate 201, a second substrate 202, an anode electrode 210, a bank layer B, and an organic light emitting diode display. The light emitting layer 220 includes a light emitting layer 220, a cathode electrode 230, a color refiner 240, and a black matrix BM.

First, the first substrate 201 and the second substrate 202 are defined by a plurality of pixels. In addition, the first substrate 201 and the second substrate 202 may be formed of glass or a flexible material. The flexible material may be formed of a material having excellent heat resistance and durability. For example, the first substrate 201 and the second substrate 202 may be made of polyethersulphone (PES), polyacrylate (PAR, polyacrylate), polyetherimide (PEI), polyimide (PI) Polyimide), polyethylene naphthalate (PET, polyethylenenapthalate), polyethylene terephthalate (PET, polyehtyleneterepthalate) may be formed of a material such as, but is not limited to the material and may be formed of low-molecular and polymer materials having excellent heat resistance and durability.

Next, an anode electrode 210 is formed on the first substrate 201. Since the anode 210 must supply holes to the organic emission layer 220, the anode electrode 210 may be formed of a material having a large work function. The anode electrode 210 may be formed of, for example, a transparent conductive oxide (TCO). Examples of the transparent conductive oxide include indium tin oxide (ITO), indium zinc oxide (IZO), and indium tin zinc oxide (ITZO).

Next, a bank layer B is formed on the first substrate 201. The bank layer B is formed to partially overlap the anode electrode 210. Preferably, the bank layer B may overlap the edge region of the anode electrode 210. The portion where the bank layer B does not overlap the anode electrode 210 is a region where the organic light emitting layer 220 and the anode electrode 210 are in contact with each other. That is, the bank layer B defines the light emitting area of the pixel.

In addition, the bank layer B improves the uniformity of emission of the organic light emitting layer 220 in the pixel. The charge is located more in the edge region of the anode electrode 210, in which case the edge of the anode electrode 210 may emit light brighter. However, the bank layer B covers the edge region of the anode electrode 210, thereby preventing the edge region of the anode electrode 210 from coming into contact with the organic light emitting layer 220 even when charge is concentrated in the edge region, thereby causing luminance within the pixel. Uniformity can be improved.

Next, an organic emission layer 220 is formed on the anode electrode 210 and the bank layer (B). The organic emission layer 220 receives holes from the anode electrode 210 and receives electrons from the cathode electrode 230 to emit light. The organic emission layer 220 emits white light L2, and the white light L2 is converted into light having a specific wavelength through the color refiner 240 formed in each pixel, and is emitted. However, the organic emission layer 220 may not be formed on the bank layer (B).

As shown in FIG. 2, the black matrix BM prevents the white light L2 from advancing to adjacent pixels. The black matrix BM may be formed in an overlapped area of the color refiner 240 after the color refiner 240 is formed, and may have a height sufficient to block light leakage. The black matrix BM may be formed in an overlapped area of the color refiner 240 to prevent light leakage between adjacent pixels.

Next, the cathode electrode 230 is formed on the organic light emitting layer 220. The cathode electrode 230 may be formed of a material having a low work function to supply electrons. For example, the cathode electrode 230 may include any one selected from silver (Ag), magnesium (Mg), calcium (Ca), neodymium (Nd), aluminum (Al), and lithium (Li). In addition, the cathode electrode 230 is formed of a thin film in order to enable light to be emitted to the outside, and may be formed to be thin to a thickness of several hundred ohms or less.

The cathode electrode 230 is formed of a thin thin film as described above in order to increase the transmittance of the white light L2 emitted from the organic light emitting layer 220, and thus, the resistance of the cathode electrode 230 is increased in a large area, thereby causing electrical conductivity. This can fall. Therefore, the metal wire (not shown) such as the auxiliary electrode and the cathode electrode 230 may be electrically connected to lower the resistance to enable normal driving.

Next, a color refiner 240 is formed on the second substrate 202. The black matrix BM is not formed first, and the color refiner 240 is formed first, and the color refiner 240 may have different colors for each pixel. For example, the color refiner 240 may have colors of red, green, and blue, which are three primary colors of light. In addition, the color refiner 240 may have white, magenta, cyan and yellow colors. The color refiner 240 may not be formed in the pixel emitting white light.

The color refiner 240 is formed in each pixel, and may be formed wider than each pixel. Accordingly, color refiners 240 of adjacent pixels may overlap at the boundary line between the pixels. In the region where the color refiner 240 overlaps, the thickness of the color refiner 240 becomes thicker than the non-overlapping region. As described above, the thickness of the color refiner 240 is increased to prevent light leakage between pixels emitting light of different colors, and to accurately express gray levels of each pixel. In addition, the color conversion shape due to the viewing angle is also prevented, so that the viewing angle can be widened.

For example, the color refiner 240 may have colors of red, green, and blue, and the color refiner 240 of pixels adjacent to each other may have different colors. The color refiners 240 of pixels adjacent to each other in the first direction may have different colors, but the color refiners 240 of pixels adjacent to each other in the first direction and, for example, in a second vertical direction may be different from each other. It may have the same color. Preferably, the first and second directions may coincide with rows and columns in the arrangement of the pixels.

The color refiner 240 having the same color may be simultaneously formed in the pixel column in the second direction, for example. The color refiner 240 having the same color formed in the pixel column in the second direction may be formed in a single stripe form without being spaced apart from each pixel. Accordingly, the color refiner 240 having the same color as each other may be formed simultaneously in a single stripe form for each pixel column in the second direction, and may overlap the color refiner 240 formed in the adjacent pixel column.

In addition, the color refiner 240 having the same color may be separately formed in each pixel in the pixel column in the second direction, for example. In this case, the color refiner 240 may be formed by overlapping the color refiner 240 having the same color. In this case, not only the light leakage between pixels having the color refiner 240 of different colors can be prevented, but also the light leakage between pixels having the color refiner 240 of the same color can be prevented, so that the correctness of each pixel can be prevented. Gradation can be expressed. In addition, when the color refiner 240 is overlapped on all sides of the pixel as described above, it is possible to prevent the color conversion phenomenon by the left and right as well as the vertical viewing angle.

Next, a black matrix BM is formed on the color refiner 240. In more detail, the black matrix BM may be formed in the overlapped areas of the color refiner 240. The black matrix BM is formed in the overlapped region of the color refiner 240, and thus the thickness of the black matrix BM is added to the overlapped thickness of the color refiner 240, thereby reducing light leakage between adjacent pixels, and reducing each pixel. The accurate gradation representation of is possible. In addition, since light leakage can be prevented, high resolution can be realized.

3 is a cross-sectional view illustrating the second substrate 202 having the color refiner 240 overlapped in the first direction.

As shown in FIG. 3, color refiners 240 having different colors are formed in adjacent pixels, and color refiners 240 formed in adjacent pixels overlap each other. The black matrix BM is formed in the overlapping area of the color refiner 240. The width of the black matrix BM may be greater than or equal to the width of the region where the color refiner 240 overlaps. Preferably, the width of the black matrix BM may be larger than the width of the region where the color refiner 240 overlaps.

The first direction may be a column direction or a row direction of the pixel. In general, pixels of the same color are arranged in the column direction, and pixels of different colors are arranged in the row direction. That is, the color refiner 240 is generally arranged in the same color in the column direction, different colors may be arranged in the row direction. Therefore, the first direction may be preferably the row direction of the pixel array. Color refiners 240 having different colors in the row direction are formed to overlap each other, and a black matrix BM is formed in the overlapped areas, so that the viewing angle in the row direction can be widened, and the color conversion phenomenon is caused by the left and right viewing angles. Can be prevented.

4 is a cross-sectional view illustrating a second substrate 250 in which color refiners 240 overlap in a second direction.

As shown in FIG. 4, color refiners 240 having the same color are formed in adjacent pixels, and color refiners 240 formed in adjacent pixels overlap each other. The black matrix BM is formed in the overlapping area of the color refiner 240. The width of the black matrix BM may be greater than or equal to the width of the region where the color refiner 240 overlaps. Preferably, the width of the black matrix BM may be larger than the width of the region where the color refiner 240 overlaps.

The second direction may be a column direction or a row direction of the pixel. In general, pixels of the same color are arranged in the column direction, and pixels of different colors are arranged in the row direction. That is, the color refiner 240 is generally arranged in the same color in the column direction, different colors may be arranged in the row direction. Therefore, the second direction may be preferably a column direction of the pixel array. The color refiners 240 having the same color in the column direction are formed to overlap each other, and the black matrix BM is formed in the overlapped area, thereby widening the viewing angle in the column direction and performing color conversion by the vertical viewing angle. You can prevent it.

5A through 5C 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 shown in FIG. 5A, an anode electrode 210 is formed on the first substrate 201 and a bank layer (1) is formed on the first substrate 201 so as to overlap an edge region of the anode electrode 210. Form B). The bank layer B defines the light emitting region of the pixel.

The organic emission layer 220 is formed on the emission area of the bank layer B and the anode electrode 210. The organic light emitting layer 220 may be formed by any one of a vacuum deposition method using a shadow mask, a laser thermal transfer method using a laser, a screen printing method, and a thermal deposition method. However, the organic emission layer 220 may not be formed on the bank layer (B). In addition, the cathode electrode 230 may be formed on the organic emission layer 220. The cathode electrode 230 includes any one of silver (Ag), magnesium (Mg), calcium (Ca), neodymium (Nd), aluminum (Al), and lithium (Li), and includes a vacuum deposition method or a sputtering method. It can be formed in any of a variety of ways.

Next, as shown in FIG. 5B, a color refiner 240 is formed for each pixel on the second substrate 202. The color refiner 240 may be formed of a photoresist that is a photosensitive material. After the photoresist is formed on the entire surface of the second substrate 202 by a spin coating method or the like, the color refiner 240 may be formed in each pixel through an exposure and development process. The color of the photoresist may match the color emitted by each pixel. In addition, the color refiner 240 is formed so that neighboring color refiner 240 overlap each other. Therefore, when the photoresist is entirely coated on the second substrate 202 and then exposed, the area of the open area of the exposure mask may be larger than the area of each pixel.

The black matrix BM may be formed in an area where the color refiner 240 overlaps. The black matrix BM may be formed in a region where the color refiner 240 overlaps with each other to more effectively prevent light leakage between adjacent pixels.

Next, as shown in FIG. 5C, the first substrate 201 and the second substrate 202 are bonded to each other so that the bank layer B and the black matrix BM correspond to each other. For example, an encapsulation layer (not shown), an adhesive layer (not shown), and an organic filling layer (not shown) may be interposed between the black matrix BM and the cathode electrode 230. Alternatively, an air layer (not shown) may be formed between the bank layer B and the black matrix BM.

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

Therefore, it is to be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention. do.

201: first substrate 202: second substrate
210: anode electrode 220 organic light emitting layer
230: cathode electrode 240: color refiner
B: bank layer BM: black matrix
L2: white light

Claims (9)

A first substrate and a second substrate defined by a plurality of pixels;
An anode formed on the first substrate;
A bank layer formed to overlap an edge region of the anode electrode and defining a light emitting region of each pixel;
An organic emission layer formed on the anode;
A cathode electrode formed on the organic light emitting layer;
A color refiner formed for each pixel on the second substrate and overlapping each other; And
A plurality of black matrices formed in an area where the color refiner overlaps, and the first substrate and the second substrate are joined to face each other such that the black matrix and the bank layer correspond to each other;
The color refiner has any one of a first color, a second color, and a third color,
The color refiners having different colors overlap each other in the first direction,
In the second direction perpendicular to the first direction, the color refiners having the same color are separately formed for each of the pixels and overlap each other.
Some of the plurality of black matrices are formed in regions where color refiners having the same color are overlapped in the second direction. The method of claim 1,
And a width of the region where the color refiner overlaps is smaller than a width of the black matrix. The method of claim 1,
2. An organic light emitting display device in which two different color refiners formed in adjacent pixels among the color refiners overlap each other. delete delete Forming an anode electrode on a first substrate defined by a plurality of pixels;
Forming a bank layer to overlap an edge region of the anode electrode;
Forming an organic emission layer on the anode;
Forming a cathode on the organic light emitting layer;
Forming a color refiner overlapping each other for each pixel on a second substrate defined by a plurality of pixels;
Forming a plurality of black matrices in the overlapped areas of the color refiner; And
Bonding the first substrate and the second substrate to face each other such that the bank layer and the black matrix correspond to each other;
The color refiner has any one of a first color, a second color, and a third color,
The color refiners having different colors overlap each other in the first direction,
In the second direction perpendicular to the first direction, the color refiners having the same color are separately formed for each of the pixels and overlap each other.
Some of the plurality of black matrices are formed in regions where color refiners having the same color are overlapped in the second direction. delete delete The method of claim 6,
And forming the color refiner separately for each of the pixels in the first direction and the second direction.

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