KR20100130303A - Organic light emitting display device and method for fabricating the same - Google Patents

Abstract

PURPOSE: An organic light emitting display device and a method for fabricating the same are provided to prevent a second electrode and an organic light emitting layer from being damaged due to the bending of a top plate by gradually increasing the spacer height of a boundary part between the edge part and the center part. CONSTITUTION: A bottom plate(110) is defined by the display area including the non-display area, the edge part, and the center part. A spacer(170) is formed on the display space of the bottom plate. A cell driving array is formed on the display area of the bottom plate. A first electrode is formed on the cell driving array and it is electrically connected to the cell driving array.

Description

Organic Light Emitting Display Device and Method for fabricating the same

The present invention relates to an organic light emitting display device and a method for manufacturing the same, and more particularly, to an organic light emitting display device and a method for manufacturing the organic light emitting display device which can prevent dark spots and stain defects and improve image quality characteristics of a display screen. It is about.

Video display devices that realize various information as screens are the core technologies of the information and communication era, and are developing in a direction of thinner, lighter, portable and high performance. With the development of the information society in recent years, various forms of display devices have increased, and flat displays such as liquid crystal display (LCD), plasma display panel (PDP), electro luminescent display (ELD), and field emission display (FED) There is an active research on the device. Among them, an organic light emitting display device that displays an image by controlling an emission amount of an organic light emitting layer as a flat panel display device that can reduce weight and volume, which is a disadvantage of a cathode ray tube (CRT), has been in the spotlight.

An organic light emitting display device is a self-luminous device using a thin light emitting layer between electrodes, and has an advantage of thinning like a paper. In an active matrix organic light emitting display device (AMOLED), pixels composed of three color (R, G, B) sub-pixels are arranged in a matrix to display an image. Each sub pixel includes an organic light emitting display device and a cell driver for independently driving the organic light emitting display device. The cell driver includes at least two thin film transistors and a storage capacitor to control the amount of current supplied to the organic light emitting display according to the data signal to control the brightness of the organic light emitting display.

In the structure of a typical organic light emitting display device, the upper plate and the lower plate are bonded by a sealant formed at an edge thereof. At this time, the sealant is formed at a predetermined height so that the gap between the upper plate and the lower plate is maintained. However, since there is a limit to the interval that can be maintained by the sealant, the phenomenon in which the upper plate is bent in the lower plate direction occurs as shown in Figs. 1A and 1B.

In particular, when there is an external impact or when the size of the substrate is increased and the upper plate and the lower plate are used in different types, the phenomenon in which the substrate is bent occurs more greatly. In this case, the upper plate comes into contact with the layers formed on the lower plate, and the second electrode and the organic light emitting layer are damaged to generate dark spot bundles and stains. In addition, the image quality of the display screen is degraded, such as a Newton's ring phenomenon due to external impact and deterioration, thereby reducing the reliability of the organic light emitting display device.

The present invention has been made to solve the above problems, and an object thereof is to provide an organic light emitting display device and a method of manufacturing the same, which can prevent dark spots and spot defects and improve image quality characteristics of a display screen.

An organic light emitting display device according to an embodiment of the present invention includes a lower plate defined by a display area including a non-display area, an edge part, and a center part, a spacer formed on the display area of the lower plate, and a non-display area. It actually includes an upper plate bonded to the lower plate, wherein the height of the spacer of the center portion is higher than the height of the spacer of the edge portion.

Here, the edge portion is an area corresponding to 0.05 times the length of the entire display area from the boundary between the display area and the non-display area to the center part, and the center part corresponds to the edge part in the entire display area. An area corresponding to 0.9 times the length of the entire display area is obtained by subtracting 0.05 times the length.

The spacer is formed of polyacrylic, polyimide, or rubber resin.

The organic light emitting display device is a cell driving array formed on the display area of the lower plate, a first electrode formed on the cell driving array and electrically connected to the cell driving array, and an opposite electrode of the first electrode. And a second electrode, an organic light emitting layer disposed between the first electrode and the second electrode to emit light, and a bank insulating layer separating the organic light emitting layer in sub-pixel units, wherein the spacers have an upper surface of the bank insulating layer. The spacer is formed in a dot, barrier, bar or stripe form.

The organic light emitting display device according to another embodiment of the present invention further includes a boundary portion between the edge portion and the center portion, wherein the height of the spacer of the center portion is higher than the height of the spacer of the boundary portion, The height of the spacer is higher than the height of the spacer of the edge portion.

Here, the height of the spacer of the boundary gradually increases.

A method of manufacturing an organic light emitting display device according to an embodiment of the present invention includes the steps of preparing a lower plate defined by a display area including a non-display area and an edge portion and a center portion, and on the lower plate on the edge portion and the center portion. Forming a spacer in the center portion, wherein the height of the spacer of the center portion is higher than the height of the spacer of the edge portion, and forming a spacer in the non-display area to bond the lower plate and the upper plate to each other. do.

In this case, the forming of the spacers is performed using two masks or a halftone mask.

In another aspect of the present invention, there is provided a method of manufacturing an organic light emitting display device, wherein the display area further includes a boundary portion between the edge portion and the center portion, and the height of the spacer portion of the center portion is greater than that of the spacer portion. It is higher than the height, and the height of the spacer of the boundary portion is higher than the height of the spacer of the edge portion.

Here, the forming of the spacer is a step of forming using a halftone mask or a multitone mask.

The present invention damages the second electrode and the organic light emitting layer by bending the upper plate by forming the height of the center spacer higher than the spacer height of the edge portion of the substrate or by gradually increasing the spacer height of the boundary portion between the edge portion and the center portion. Can be prevented.

In addition, the image quality of the display screen may be improved by preventing dark spots and unevenness of the large area organic light emitting display device, thereby improving reliability of the organic light emitting display device.

Hereinafter, an organic light emitting display device and a method of manufacturing the same according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a cross-sectional view schematically illustrating an organic light emitting display device according to a first embodiment of the present invention, and FIG. 3 is a cross-sectional view illustrating sub pixels of the organic light emitting display device shown in FIG. 2.

The organic light emitting display device according to the first exemplary embodiment of the present invention includes a cell driving array 120 formed on the display area A of the lower panel 110 defined by the display area A and the non-display area B, The organic light emitting diode array 130 includes a plurality of spacers 170, and an upper plate 150 bonded to the lower plate 110 by a material 152. The organic electroluminescent display device according to the first embodiment has an absorbent (not shown) such as a capping layer (not shown) for protecting the structure between the lower plate 110 and the upper plate 150 and a getter for absorbing moisture therein. ) May be further included.

The cell driving array 120 formed in the display area A of the lower panel 110 includes a plurality of sub pixel drivers, and one sub pixel driver includes a plurality of signal lines, transistors, capacitors, and a plurality of insulating layers. The transistor includes a switching transistor and a driving transistor.

The switching transistor supplies a data signal from the data line in response to the scan signal of the gate line, and the driving transistor 122 shown in FIG. 3 responds to the data signal from the switching transistor. The amount of current flowing through 130 is controlled. The capacitor serves to allow a constant current to flow through the driving transistor 122 even when the switching transistor is turned off.

The driving transistor 122 includes a gate electrode, a semiconductor layer overlapping the gate electrode with the gate insulating layer interposed therebetween, and a source / drain electrode using the semiconductor layer as a channel. Each driving transistor 122 is electrically connected to the organic light emitting diode through a contact hole of the passivation layer 124 formed on the driving transistor 122.

The organic light emitting diode array 130 includes a plurality of organic light emitting diodes, and the organic light emitting diodes display predetermined image information by emitting red, green, and blue light according to the flow of current. The organic light emitting diode includes a first electrode 132 connected to the driving transistor 122, a second electrode 136 serving as an opposite electrode, and an organic light emitting layer 134 disposed between the light emitting diodes 134. The first electrode 132 and the second electrode 136 are insulated from each other, and light is emitted by applying voltages of different polarities to the organic light emitting layer 134.

The first electrode 132 is used as an anode electrode and is formed on the passivation layer 124 to be electrically connected to the drain electrode of the driving transistor 122 through a contact hole formed in the passivation layer 124. In this case, the first electrode 132 is formed so as not to be connected to the first electrode 132 of the adjacent subpixel by being spaced a predetermined distance from the boundary of the subpixel.

When the organic light emitting display device is designed for back emission, the first electrode 132 is formed of a transparent conductive layer. As the transparent conductive layer, indium tin oxide (ITO), tin oxide (TO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), or these It is formed by the combination of. When the organic light emitting display device is configured to emit light in full emission, the first electrode 132 may be formed of Cr, Al, AlNd, Mo, Cu, W, Au, Ni, Ag, or the like, and an alloy, an oxide, or a multilayer thereof. It can also be formed as a multilayer.

The organic emission layer 134 is a layer in which light is emitted while the axtone formed by combining holes and electrons injected from the first electrode 132 and the second electrode 136 falls to the ground state, and the bank insulation layer 138. It is formed on the first electrode 132 exposed by). The organic light emitting layer 134 may include a hole injection layer (HIL), a hole transporting layer (HTL), an emission layer (EML), an electron transporting layer (ETL), and an electron injection layer (HTL). electron injection layer (EIL). In this case, the organic light emitting layer 134 is separated into subpixel units by the bank insulating layer 138, and emits red, green, and blue light in the subpixel units.

The second electrode 136 is used as a cathode electrode and is formed on the entire display area A of the lower plate 110. When the organic light emitting display device is designed for back emission, the second electrode 136 may be formed of Cr, Al, AlNd, Mo, Cu, W, Au, Ni, Ag, or the like, and their alloys, oxides, or multilayers. It can also be formed as a multilayer.

When the organic light emitting display device is designed for top emission, the second electrode 136 is formed of a transparent conductive layer so that the work function is high and light emitted from the organic light emitting layer 134 can come out of the device. As the transparent conductive layer, indium tin oxide (ITO), tin oxide (TO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), or these It is formed by the combination of.

The organic light emitting diode formed as described above may be divided into sub-pixel units by the bank insulating layer 138 to represent an image. The bank insulating layer 138 insulates the second electrode 136 of the organic light emitting diode and other wirings or elements formed thereunder so as not to interfere with each other. To this end, the bank insulating layer 138 is formed on the non-light emitting region of the lower plate 110 so as to cover the first electrode 132 on the driving transistor 122 and expose the first electrode 132 of the light emitting region. . As a material of the bank insulating layer 138, an organic material or an inorganic material may be used.

A spacer 170 is formed on the bank insulating layer 138 to prevent the top plate 150 from being pressed. The spacer 170 has a predetermined thickness so that a constant gap is maintained between the lower plate 110 and the upper plate 150, and the height of the spacer 170 of the center portion is higher than the height of the spacer 170 of the edge portion. At this time, the height difference between the spacer 170 of the edge portion and the spacer 170 of the center portion is set to 10 μm or less.

Here, as shown in FIG. 4, in the lower plate 110 defined by the display area A and the non-display area B, the edge area is the display area A that is a boundary between the display area A and the non-display area B. As shown in FIG. 0.05A in the direction of the center of the transverse from the edge of (). In the case where the vertical length of the display area A is D, the length becomes 0.05D from the boundary between the display area A and the non-display area B in the vertical center direction. The center portion becomes 0.9A of the center horizontal length and 0.9D of the vertical length D, which are the regions where the edge portions are subtracted from the entire display area A, that is, the excluded region.

When the height of the spacer 170 is the same as a whole, a Newton ring phenomenon is generated from the center part by external pressure such as a push test. However, when the height of the spacer 170 of the center portion is formed higher than the height of the spacer 170 of the edge portion as in the present invention, it is possible to prevent the Newton ring phenomenon from occurring. In addition, it is possible to prevent damage to the organic light emitting device due to the pressing, thereby improving the image quality characteristics of the display screen, such as to prevent the occurrence of dark spots and stains of the organic light emitting display device.

Polyacryl (PA), polyimide (PI), or rubber resin may be used as the material of the spacer 170. In the case of using the inorganic insulating material as the spacer material, there is a limit in increasing the height of the spacer due to the characteristics of the inorganic insulating material, and thus, one of the above materials may be selected and used as the material of the spacer in the present invention.

As illustrated in FIG. 5A, the spacer 170 may be formed in a dot shape between subpixels of R, G, and B defined by the emission color of the organic emission layer 134. In addition, the spacer 170 may be formed in a barrier form surrounding the sub-pixel as shown in FIG. 5B. In addition, the spacer 170 may be formed in the form of a bar or stripe across the pixels of R, G, and B, as shown in FIG. 5C. The spacing of the spacers 170 may be formed to be one per one subpixel or one per two subpixels, but may be designed according to the total panel area.

FIG. 6 is a schematic cross-sectional view of an organic light emitting display device according to a second exemplary embodiment of the present invention, and FIG. 7 is a cross-sectional view illustrating sub pixels of the organic light emitting display device shown in FIG. 6. In the second embodiment, the cell driving array 220 except for the spacer 270, the organic light emitting diode array 230, and the upper plate 250 bonded to the lower plate 210 by the material 252 are described in the first embodiment. As it is the same as the description thereof will be omitted.

The spacer 270 according to the second embodiment has a predetermined thickness such that a constant gap is maintained between the lower plate 210 and the upper plate 250. The height of the spacer 270 of the center portion is the height of the spacer 27 of the boundary portion. It is formed even higher, the height of the spacer 270 of the boundary portion is formed higher than the height of the edge portion. In this case, the spacer 270 of the boundary part is formed to gradually increase in the direction of the center part from the edge part. Here, the boundary portion is defined as the boundary region of the edge portion and the center portion.

As the material of the spacer 270, polyacryl (PA), polyimide (PI), or rubber resin may be used. In the case of using the inorganic insulating material as the spacer material, there is a limit in increasing the height of the spacer due to the characteristics of the inorganic insulating material. Choose one of the rubber resins.

The spacer 270 may be formed in a dot form, a barrier form surrounding the sub pixel, a bar or stripe across the pixel. The spacing of the spacers 270 may be formed to be one per one subpixel or one per two subpixels, but may be designed according to the total panel area.

As such, the present invention allows the height of the spacer 270 at the boundary to be gradually increased to prevent the spacer from being damaged by external pressure due to a step that is rapidly increasing, and further improves the ability to support the top plate 250. In addition, according to the present invention, the height of the spacer 270 of the center portion is higher than the height of the spacer 270 of the boundary portion, and the height of the spacer 270 of the edge portion is higher than the height of the spacer 270 of the boundary portion. The Newton ring phenomenon can be prevented from occurring in the center portion of the display device. In addition, it is possible to prevent damage to the organic light emitting device due to the pressing, thereby improving the image quality characteristics of the display screen, such as to prevent the occurrence of dark spots and stains of the organic light emitting display device.

Specifically, as shown in FIG. 8A, the number of defects generated per substrate was 8.7 in the related art, but when the spacer structure according to the present invention was formed, the number of defects generated per substrate was 5.4. As such, it can be seen that the present invention reduces the number of defects generated per substrate by 31% compared to the prior art. In addition, as shown in FIG. 8B, the defect rate according to the dark point was 16.7% in the related art, but when the spacer structure was formed as in the present invention, the defect rate according to the dark point was 7.4%. As such, it can be seen that the present invention improved the defect rate according to the dark point by 55.7% as compared with the prior art.

Hereinafter, a method of manufacturing the organic light emitting display device according to the first and second embodiments will be described with reference to FIGS. 9A to 9C and FIGS. 10A to 10C.

(First embodiment)

Referring to FIG. 9A, first, a driving transistor 122 formed in a sub pixel unit, a planarization film 124 covering the driving transistor 122, a driving transistor 122 and a planarization film 124. A lower plate 110 having a first electrode 132 electrically connected thereto and a bank insulating layer 138 exposing a predetermined region of the first electrode 132 is prepared. In this case, the lower plate 110 is defined as a display area including a non-display area and an edge part and a center part, and each edge part and center part is defined as a light emitting area and a non-light emitting area.

The driving transistor 122 is formed in the non-light emitting region of the lower plate 110 in sub pixel units. Although not shown, on the substrate 110, a switching transistor serving as a switch in addition to the driving transistor 120, a plurality of wirings (not shown) for supplying power and driving signals to the device, and the driving transistor 122. ) May further form a storage capacitor (not shown) that serves to allow a constant current to flow.

Cr, Al, AlNd, Mo, Cu, W, Au, Ni, Ag, etc. may be sputtered on the first electrode 132 formed on the planarization layer 124 to be electrically connected to the drain electrode of the driving transistor 122. It may be formed by a deposition method of, and may be formed of a multilayer of these alloys or oxides or ITO / reflective film / ITO.

The bank insulating layer 138 separates the organic light emitting diode into each sub-pixel unit. The bank insulating layer 138 is formed in the non-light emitting region of the lower panel 110 in which the driving transistor 122 is formed to form the first electrode ( 132).

Referring to FIG. 9B, a spacer 170 may be formed on the bank insulating layer 138 to prevent the top plate from being pressed.

Specifically, an insulating material is deposited on the entire surface of the lower plate 110 including the bank insulating layer 138 by a deposition method. Polyacryl (PA), polyimide (PI), or rubber resin may be used as an insulating material constituting the spacer 170. When an inorganic insulating material such as a silicon nitride film or a silicon oxide film is used as the spacer material, there is a limit in increasing the height of the spacer due to the characteristics of the inorganic insulating material. However, the present invention selects and uses one of the above-described polyacryl (PA), polyimide (PI), or rubber resin (rubber resin) other than the inorganic insulating material as the material of the spacer 170. It is easy to increase the height to the design value.

Next, the insulating material is selectively selected using the patterning process twice using the mask or the halftone mask 180 in which the blocking region 180a, the transflective region 180b, and the transmissive region 180c are designed at predetermined positions. Remove In this case, the halftone mask 180 is aligned so that the blocking region 180a corresponds to the center portion, the transflective region 180b corresponds to the edge portion, and the transmissive region 180c corresponds to the entire region where no spacer is formed.

Next, an exposure process is performed by irradiating the entire surface of the lower plate 110 on which the halftone mask 180 is aligned, such as ultraviolet rays, and then develops a process of removing an insulating material in a region whose properties are changed by the exposure process. . In this case, the insulation material corresponding to the transmission region 180c is completely removed to expose a predetermined region of the first electrode 132 and the bank insulating layer 138. The insulating material on the bank insulating layer 138 at the edge portion directly below the transflective region 180b is removed to a predetermined depth to have a first height, and the bank insulating layer 138 at the center portion directly below the blocking region 180a. The insulating material of the phase has a second height. In this case, the second height is higher than the first height so that the spacer 170 of the center portion is higher than the spacer 170 of the edge portion, and the height difference is 10 μm or less.

The spacer 170 may be formed in a dot form, a barrier form surrounding the sub pixel, a bar or stripe across the pixel. The spacing of the spacers 170 may be formed to be one per one subpixel or one per two subpixels, but may be designed according to the total panel area.

When the height of the spacer 170 is the same as a whole, a Newton ring phenomenon is generated from the center part by external pressure such as a push test. However, when the height of the spacer 170 of the center portion is formed higher than the height of the spacer 170 of the edge portion as in the present invention, it is possible to prevent the Newton ring phenomenon from occurring. In addition, it is possible to prevent damage to the organic light emitting device due to the pressing, thereby improving the image quality characteristics of the display screen, such as to prevent the occurrence of dark spots and stains of the organic light emitting display device.

Referring to FIG. 9C, after the organic light emitting layer 134 is formed in the light emitting region, the second electrode 136 is sequentially formed on the front surface of the light emitting region and the non-light emitting region, and the lower plate 110 and the upper plate are formed of the real 152. Adhesion 150.

Specifically, the organic light emitting layer 134 formed of an organic material is formed on the sidewall of the bank insulating layer 138 and the first electrode 132 exposed by the bank insulating layer 138 through a deposition method such as thermal deposition. . The organic light emitting layer 134 may include a hole injection layer (HIL), a hole transporting layer (HTL), an emission layer (EL), an electron transporting layer (ETL), and an electron injection layer (HTL). electron injection layer (EIL). Here, the organic light emitting layer 134 is separated by the bank insulating layer 138 in units of sub pixels, and is formed to emit red, green, and blue light in units of sub pixels.

Subsequently, after the transparent conductive layer is deposited on the organic light emitting layer 134, the second electrode 136 is formed through a photolithography process and an etching process using a mask. Indium Tin Oxide (ITO), Tin Oxide (TO), Indium Zinc Oxide (IZO), Indium Tin Zinc Oxide (ITZO), or a transparent conductive layer Combination is used.

Next, after the real material 152 is coated on the non-display area of the lower plate 110, the lower plate 110 and the upper plate 150 are bonded together to complete the organic light emitting display device according to the first embodiment. Meanwhile, the organic light emitting display device according to the first embodiment includes a capping layer (not shown) for protecting the structure between the lower plate 110 and the upper plate 150, and an absorbent such as a getter for absorbing moisture therein ( Not shown).

(Second embodiment)

Since the method of manufacturing the organic light emitting display device according to the second embodiment is the same as that of the first embodiment except for forming the spacer, a description of the step of forming the same structure will be omitted.

Referring to FIG. 10A, first, a driving transistor 222 formed in sub pixel units, a planarization film 224 covering the driving transistor 222, and a driving transistor 222 through the planarization film 224. A lower plate 210 having a first electrode 232 electrically connected thereto and a bank insulating layer 238 exposing a predetermined region of the first electrode 232 is prepared. In this case, the lower plate 210 is defined as a display area including a non-display area and an edge part, a boundary part, and a center part, and each edge part, boundary part, and center part is defined as a light emitting area and a non-light emitting area.

Referring to FIG. 10B, a spacer 270 is formed on the bank insulating layer 238 to prevent the top plate from being pressed.

Specifically, an insulating material is deposited on the entire surface of the lower plate 210 including the bank insulating layer 238 by a deposition method. Polyacryl (PA), polyimide (PI), or rubber resin (rubber resin) is used as an insulating material constituting the spacer 270. When an inorganic insulating material such as a silicon nitride film or a silicon oxide film is used as the spacer material, there is a limit in increasing the height of the spacer due to the characteristics of the inorganic insulating material. However, according to the present invention, it is easy to increase the height of the spacer 270 to a design value by selecting and using one of the aforementioned materials other than the inorganic insulating material as the material of the spacer 270.

Subsequently, a halftone mask or a multitone mask 280 having a transmissive region 280a, a first transflective region 280b, a second transflective region 280c, and a blocking region 280d is designed. To remove the insulating material selectively. At this time, the blocking region 280d is at the center portion, the second semi-transmissive region 280c is at the boundary portion, the first semi-transmissive region 280b is at the edge portion, and the transmissive region 280a is the entire region where no spacer is formed. Align the multitone mask 280 to correspond.

Next, after the exposure process is performed by irradiating light such as ultraviolet rays to the entire surface of the lower plate 210 on which the multitone mask 280 is aligned, a development process of removing an insulating material in a region whose properties are changed by the exposure process is performed. . In this case, the insulating material corresponding to the transmission region 280a is completely removed to expose a predetermined region of the first electrode 232 and the bank insulating layer 238. The insulating material on the bank insulating layer 238 of the edge portion directly below the first transflective region 280b is removed to a predetermined depth to have a first height, and the boundary portion directly below the second transflective region 280c. The insulating material on the bank insulating layer 238 is removed to a certain depth to have a second height, and the insulating material on the bank insulating layer 238 of the center portion directly below the blocking region 280c has a third height.

At this time, the second height is higher than the first height, and the third height is higher than the second height so that the spacer 270 of the boundary is higher than the spacer 270 of the edge and the center of the spacer 270 of the boundary. The negative spacer 270 is formed higher. The spacers 270 in the boundary portion may be formed to have the same height or may have a height gradually increasing from the edge portion toward the center portion.

The spacer 270 may be formed in a dot form, a barrier form surrounding the sub pixel, a bar or stripe across the pixel. The spacing of the spacers 270 may be formed to be one per one subpixel or one per two subpixels, but may be designed according to the total panel area.

As such, the present invention allows the height of the spacer 270 at the boundary to be gradually increased, thereby preventing the spacer from being damaged by external pressure due to a rapidly increasing step and further improving the ability to support the top plate. In addition, according to the present invention, the height of the spacer 270 of the center portion is higher than the height of the spacer 270 of the boundary portion, and the height of the spacer 270 of the edge portion is higher than the height of the spacer 270 of the boundary portion. The Newton ring phenomenon can be prevented from occurring in the center portion of the display device. In addition, it is possible to prevent damage to the organic light emitting device due to the pressing, thereby improving the image quality characteristics of the display screen, such as to prevent the occurrence of dark spots and stains of the organic light emitting display device.

Referring to FIG. 10C, after the organic emission layer 234 is formed in the emission area, the second electrode 236 is sequentially formed on the entire surface of the emission area and the non-emission area. Next, after the real material 252 is applied to the non-display area of the lower plate 210, the lower plate 210 and the upper plate 250 are bonded together to complete the organic light emitting display device according to the second embodiment. Meanwhile, the organic light emitting display device according to the second exemplary embodiment includes a capping layer (not shown) for protecting the structure between the lower plate 210 and the upper plate 250, and an absorbent such as a getter for absorbing moisture therein ( Not shown).

The above-described techniques represent presently preferred embodiments, and the present invention is not limited to the above-described embodiments and the accompanying drawings. Modifications and other uses of the embodiments will be apparent to those skilled in the art, and such changes and other uses are defined by the scope of the claims contained within or appended to the spirit of the invention.

1A and 1B illustrate a phenomenon in which a top plate of an organic light emitting display device according to the prior art is bent.

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

3 is a cross-sectional view illustrating a subpixel of the organic light emitting display device illustrated in FIG. 2.

4 is a diagram illustrating a region in which a spacer is formed in an organic light emitting display device according to an exemplary embodiment of the present invention.

5A to 5C are diagrams illustrating shapes of spacers of the organic light emitting display device according to the present invention.

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

FIG. 7 is a cross-sectional view illustrating subpixels of the organic light emitting display device illustrated in FIG. 6.

8A and 8B are comparative graphs showing the number of defects and a defective rate in forming a spacer structure according to the prior art and the present invention.

9A to 9C are cross-sectional views illustrating a method of manufacturing the organic light emitting display device according to the first embodiment shown in FIG. 2.

10A to 10C are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to the second embodiment shown in FIG. 6.

<< Explanation of symbols for main part of drawing >>

110, 210: lower plate 122, 222: driving transistor

124 and 224: protective films 132 and 232: first electrode

134 and 234: organic light emitting layer 136 and 236: second electrode

138 and 238: bank insulating layers 170 and 270: spacer

180: halftone mask 280: multitone mask

Claims (10)

A lower plate defined by a non-display area and a display area including an edge part and a center part; A spacer formed on the display area of the lower plate; And An upper plate bonded to the lower plate with a material formed in the non-display area, The height of the spacer of the center portion is higher than the height of the spacer of the edge portion. The display apparatus of claim 1, wherein the edge portion is an area corresponding to 0.05 times the length of the entire display region in a direction of the center portion from a boundary between the display region and the non-display region, And the center portion is an area corresponding to 0.9 times the length of the entire display area, subtracting the 0.05 times the length corresponding to the edge portion from the entire display area. The organic light emitting display device of claim 1, wherein the spacer is formed of polyacryl, polyimide, or rubber resin. The display device of claim 1, further comprising: a cell driving array formed on the display area of the lower plate; A first electrode formed on the cell drive array and electrically connected to the cell drive array; A second electrode which is a counter electrode of the first electrode, An organic light emitting layer disposed between the first electrode and the second electrode and emitting light; A bank insulating layer separating the organic light emitting layer in sub pixel units; The spacer is formed on the upper surface of the bank insulating layer, The spacer is an organic light emitting display device having a dot, barrier, bar, or stripe shape. The method of claim 1, further comprising a boundary between the edge portion and the center portion, The height of the spacer of the center portion is higher than the height of the spacer of the boundary portion, and the height of the spacer of the boundary portion is higher than the height of the spacer of the edge portion. The organic light emitting display device as claimed in claim 5, wherein the height of the spacer of the boundary is gradually increased. Preparing a bottom plate defined by a non-display area and a display area including an edge part and a center part; Forming a spacer on the lower plate of the edge portion and the center portion, wherein the spacer has a height higher than that of the spacer of the edge portion; And And forming an actual material in the non-display area to bond the lower plate and the upper plate to each other. The method of claim 7, wherein the forming of the spacers is performed using two masks or a halftone mask. The display device of claim 7, wherein the display area further comprises a boundary portion between the edge portion and the center portion. And the height of the spacer of the center portion is higher than the height of the spacer of the boundary portion, and the height of the spacer of the boundary portion is higher than the height of the spacer of the edge portion. 10. The method of claim 9, wherein the forming of the spacers is performed by using a halftone mask or a multitone mask.

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