KR20100072642A - Metal mask and organic electroluminescence display using the same - Google Patents

Abstract

PURPOSE: A metal mast and an organic electric field radiating indicating element using the same are provided to exclude a spacer by regularly maintaining a distance between a substrate and the metal mask through a first to a third projection. CONSTITUTION: A metal mask includes a concave part(140), an opening(150) and a partition wall(130). The partition wall includes a first to a third projection(130a~130c) and a connection part(130d). The connection part connects the first and the third projection. The concave part includes a first and a second concave part. The first concave part is formed by the first and the second projection. The second concave part is formed by the second and the third projection. The opening is formed by the first and the third projection and the connection part.

Description

Metal mask and organic electroluminescent display device using the same {METAL MASK AND ORGANIC ELECTROLUMINESCENCE DISPLAY USING THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal mask, and in particular, misalignment due to dark spot defects caused by contact between a metal mask and a substrate and invasion of adjacent pixels during deposition of an organic light emitting layer of an organic electroluminescence display. The present invention relates to a metal mask and an organic electroluminescent display device using the same.

Recently, various flat panel display devices that can reduce weight and volume, which are disadvantages of cathode ray tubes, have been developed. In particular, studies are being actively conducted to improve display quality and large screens. Such flat panel displays include liquid crystal displays, field emission displays, plasma display panels, and electroluminescence displays.

The electroluminescent display device used in the electroluminescent display device is a self-luminous device having a light emitting layer formed between two electrodes, and is an inorganic electroluminescent device and an organic electroluminescent device depending on the material of the light emitting layer. Therefore, the top emission type, the bottom emission type and the dual emission typy, and the passive matrix type and the active matrix type depending on the driving method Are separated by).

Since the electroluminescent display device is a self light-emitting type, the viewing angle is wider, the contrast is higher, and the visibility is superior to other display devices. In addition, since the backlight is unnecessary, the thin and light weight can be realized, and since the current needs to be supplied only to the pixel that needs light emission, power consumption is greatly reduced.

In addition, the passive matrix type electroluminescent display device of the electroluminescent display device according to the driving method is simple in its configuration, but the manufacturing method is simple, but it is difficult to increase the power consumption and the display area, and the opening ratio decreases as the number of wiring increases. On the other hand, an active matrix type electroluminescent display device has an advantage of providing high luminous efficiency and high image quality. Therefore, the passive matrix type electroluminescent display device is applied to the small display device, and the active matrix type electroluminescent display device is applied to the large display device.

Conventional active matrix organic electroluminescent display devices have a transparent substrate, an anode formed in a stripe form by a chemical etching method on the transparent substrate, and a metal mask contacts the substrate when the organic light emitting layer is deposited on the substrate in a later process. A spacer formed to prevent the organic light emitting layer, an organic light emitting layer formed by sequentially depositing red, green, and blue organic light emitting materials on each pixel region on the transparent substrate using a metal mask in the evaporator, and a metal on the organic light emitting layer And a cathode electrode formed by depositing an electrode.

In the structure of the active matrix organic electroluminescent display device as described above, when the organic light emitting layer is formed in each pixel region on the substrate, first, a red (R) color is used by using a metal mask having an opening having one pixel size. An organic light emitting layer is formed by forming an organic light emitting material, shifting a metal mask by one pixel cell, and then forming an organic light emitting material of green (G) color and an organic light emitting material of blue (B) color.

As described above, in a conventional active matrix organic electroluminescent display device, a spacer is generally formed in order to prevent a defect caused by contact of a metal mask with a substrate in a deposition process of forming an organic light emitting layer. This is because when the spacer is formed, the gap between the metal mask and the substrate is maintained by the spacer, so that the metal mask is in direct contact with the light emitting region of the pixel.

However, in the conventional active matrix organic electroluminescent display device, forming the spacer is to maintain the separation distance between the metal mask and the substrate when forming the organic light emitting layer, that is, when the red, green, and blue light emitting materials are deposited on the substrate. If only the distance between the metal mask and the substrate can be secured, it can be removed. In particular, since the formation of the spacer requires a plurality of processes for depositing the spacer material and removing the spacer material so as to remain only in necessary portions, the process cost increases accordingly. In addition, the spacer may not effectively prevent invasion of other colors from adjacent pixel cells, and may cause dark spots due to contact of the metal mask and the substrate.

Accordingly, an object of the present invention is to properly maintain the distance between the metal mask and the substrate without spacers when forming the organic light emitting layer of the active matrix organic electroluminescent display device, to prevent invasion of other colors from adjacent pixel cells, and to reduce dark spot defects. To provide a metal mask that can give.

According to an aspect of the present invention, there is provided a metal mask comprising a plurality of recesses and openings formed at predetermined intervals in a predetermined position; And a plurality of partitions defining the recesses and the openings.

In the above configuration, each of the plurality of partitions includes a linear first projection, a second projection and a third projection, wherein the recess includes a linear first recess and a second recess. .

In the above configuration, the first concave portion is formed by the first projection portion and the second projection portion of each partition, characterized in that the second concave portion is formed by the second projection portion and the third projection portion of the partition wall. .

In the above configuration, the opening may include: first protrusions of the partition walls; Third protrusions of the partition wall adjacent to each of the partition walls; And a third partition wall formed by a connection part disposed at a predetermined interval to connect the first projection part of each partition wall and the third projection part of the neighboring partition wall, or the first partition wall of each partition wall and the third partition wall adjacent to each partition wall. It characterized by being formed linearly by.

The width and depth of the first concave portion may be the same as the width and depth of the second concave portion, respectively, and the width of the opening may be equal to the width of the first concave portion.

The present invention also features an organic electroluminescent display device manufactured using the metal mask described above.

According to the metal mask according to the present invention, since the spacer structure used for forming the organic light emitting layer of the active matrix organic electroluminescent display device is unnecessary, the process for forming the spacer is eliminated, thereby reducing the process cost, and the line formed on the metal mask. It is possible to effectively prevent invasion of the tar color by the mold protrusion, and to obtain an effect of preventing defects of dark spots due to the contact of the metal mask and the substrate.

Hereinafter, with reference to the accompanying drawings will be described a preferred embodiment according to the present invention. Hereinafter, the same components will be given the same reference numerals to clarify the description.

<First Embodiment>

1, 2A and 2B illustrate a slot type metal mask for fabricating an organic electroluminescent display device according to a first embodiment of the present invention. FIG. 1 is a plan view of a metal mask, and FIG. 2A is a view of FIG. An enlarged plan view of a portion A, and FIG. 2B is a cross-sectional view of the metal mask shown in FIG. 2A taken along the line II ′.

Referring to FIG. 1, a slot type metal mask 110 according to a first embodiment of the present invention includes a deposition unit 120 for depositing an organic light emitting material.

Referring to a cross-sectional view of FIG. 2B, which is taken along line II ′ of FIG. 2A and FIG. 2A, which is an enlarged view of part A of FIG. 1, the deposition portion of the metal mask according to the first embodiment of the present invention ( 120 may include a plurality of recesses 140 and openings 150 having a size corresponding to the pixel cell region, and first protrusions 130a to third protrusions defining the recesses 140 and the opening 150. And a partition wall 130 including a connecting portion 130d connecting the first protrusion 130a and the third protrusion 130c.

In the metal mask of the first embodiment, each partition wall 130 includes a first protrusion 130a, a second protrusion 130b, and a third protrusion 130c having a linear shape, and each barrier 130 is a barrier 130. ) And a plurality of connecting portions 130d arranged at regular intervals so as to cross the adjacent partition wall.

The recess 140 includes a line-shaped first recess 140a and a second recess 140b, and the first recess 140a is formed with the first protrusion 130a of each partition wall 130. The second protrusion 130b is formed by the second protrusion 130b, and the second recess 140b is formed by the second protrusion 130b and the third protrusion 130c of the partition 130. In addition, the width and depth of the first recess 140a is preferably the same as the width and depth of the second recess 140b, respectively.

The opening 150 is formed in a lattice form by the connecting portion 130d connecting the partitions 130 and the partitions 130 and neighboring partitions. More specifically, the opening 150 may include a first protrusion 130a of each of the barrier ribs 130, a third protrusion 130c of a barrier rib adjacent to each of the barrier ribs 130, and each of the barrier ribs 130. It is formed by the connecting portion (130d) for connecting the first projection portion 130a of the third projection portion 130a of the neighboring partition wall (130). The width of the opening 150 is preferably the same as the width of the first recess 140a.

Since the recess 140 and the opening 150 constituting the deposition unit 120 can be manufactured at once by double-sided etching, the manufacturing process is very simple. The organic light emitting material of the color to be currently deposited is deposited through the opening 150 of the evaporation unit 120 formed as described above, and the organic light emitting material of the previously deposited color is deposited on the recess 140. Is accepted. In addition, since the opening 150 of the metal mask 110 is formed in a lattice shape separated by the connection portion 130d of the partition wall 130, the organic light emitting layer is also formed in a lattice shape.

According to the slot-type metal mask 110 according to the first embodiment of the present invention described above, the distance between the metal mask and the substrate may be kept constant by the first to third protrusions 130a to 130c. The spacer formed during deposition of the organic light emitting material becomes unnecessary. Therefore, the process for forming the spacer is unnecessary, and the process cost can be significantly reduced. In addition, since the organic light emitting material in the neighboring pixel cell area is prevented from invading by the first to third protrusions 130a to 130c, misalignment due to other color invasion can be prevented. In addition, since the center is well supported by the first to third protrusions 130a to 130c when the metal mask is in contact with the substrate during deposition of the organic light emitting material, it is possible to minimize dark spots due to the imprinting.

&Lt; Embodiment 2 >

3, 4A and 4B illustrate a grill type metal mask for manufacturing an organic electroluminescent display device according to a second embodiment of the present invention. FIG. 3 is a plan view of the metal mask. 4A is an enlarged plan view of portion A of FIG. 3, and FIG. 4B is a cross-sectional view of the metal mask illustrated in FIG. 4A taken along the line II-II ″.

Compared to the metal mask 110 of the first embodiment, the metal mask 210 of the second embodiment is the first embodiment except that the openings formed by the partition walls and neighboring partition walls are not connected by the connecting portion. It is the same as the structure of the metal mask 110 according to.

Referring to FIG. 3, the grill type metal mask 210 according to the second embodiment of the present invention includes a deposition unit 220 for depositing an organic light emitting material.

Referring to the cross-sectional view taken along the line II-II ′ of FIGS. 4A and 4A showing the enlarged portion B of FIG. 3, the deposition unit 220 of the metal mask according to the second embodiment of the present invention may include a pixel cell. A partition wall having a recess 240 and an opening 250 having a size corresponding to an area, and a first protrusion 230a to a third protrusion 130c defining the recess 240 and the opening 250. 130.

In the metal mask 210 of the second exemplary embodiment, each partition wall 230 includes a first protrusion 230a, a second protrusion 230b, and a third protrusion 230c having a linear shape.

The recess 240 includes a line-shaped first recess 240a and a second recess 240b, and the first recess 240a is formed with the first protrusion 230a of each partition wall 230. It is formed by the second protrusion 230b, the second recess 240b is formed by the second protrusion 230b and the third protrusion 230c of the partition 230. In addition, the width and depth of the first recess 240a is preferably the same as the width and depth of the second recess 240b.

The opening 250 is formed by the partition walls adjacent to each of the partition walls 230. More specifically, the opening 150 is formed by the first protrusion 230a of each of the barrier ribs 230 and the third protrusion 230c of the barrier rib adjacent to each of the barrier ribs 230. The width of the opening 250 is preferably the same as the width of the first recess 240a.

Since the concave portion 240 and the opening portion 250 constituting the vapor deposition portion 220 can be manufactured at once by double-sided etching, the manufacturing process is very simple. In the opening 250 of the deposition unit 220 formed as described above, an organic light emitting material having a color to be currently deposited in the organic light emitting material deposition process is deposited through the opening 250, and a color previously deposited in the recess 240. Organic light emitting material is accommodated.

According to the grill-type metal mask according to the second embodiment of the present invention described above, since the distance between the metal mask and the substrate can be kept constant by the first to third protrusions 230a to 230c, a general organic light emitting material Spacers formed during deposition become unnecessary. Therefore, the process for forming the spacer is unnecessary, and the process cost can be significantly reduced. In addition, since the organic light emitting material in the neighboring pixel cell area is prevented from invading by the first to third protrusions 230a to 230c, misalignment due to other color invasion can be prevented. In addition, since the center is well supported by the first to third protrusions 230a to 230c when the metal mask is in contact with the substrate when the organic light emitting material is deposited, it is possible to minimize dark spots due to the imprinting.

<Method of manufacturing organic electroluminescent display device using metal mask of the present invention>

5A to 5D are views for explaining a method of manufacturing organic electroluminescent display irradiation using the metal mask shown in FIGS. 1 and 3.

5A to 5D, first, a transparent electrode 310 is formed on the transparent substrate 300 of the organic light emitting display device (FIG. 5A).

Next, in order to form the organic emission layer, the transparent substrate 300 on which the transparent electrode 310 is formed is introduced into a deposition machine (not shown). In order to deposit the organic light emitting material on the transparent electrode 310 in the evaporator, as shown in FIGS. 1 and 3, metal masks 110 and 210 having barrier ribs 130 and 230 are arranged.

When the red organic light emitting material is deposited through the openings 150 and 250 of the metal masks 110 and 210, the red organic light emitting layer R as illustrated in FIG. 5B is formed. When the red organic emission layer R is formed, the metal masks 110 and 210 are shifted by one pixel cell. When the green organic light emitting material is deposited through the openings 150 and 250 using the shifted metal masks 110 and 210, the green organic light emitting layer G is formed as illustrated in FIG. 5C, and the red color formed in the previous process is formed. The organic emission layer R is accommodated in the recesses 140 and 240 formed by the partition wall 130. When the green organic emission layer G is formed in this manner, the metal masks 110 and 210 are shifted by one pixel cell again. When the blue organic light emitting material is deposited through the openings 150 and 250 using the shifted metal masks 110 and 210, a blue organic light emitting layer B is formed as illustrated in FIG. 5D, and the red organic light formed in the previous process is formed. The light emitting layer R is accommodated in the recesses 140 and 240 formed by the partition wall 130. The red organic light emitting layer R and the blue organic light emitting layer G formed in the previous process are accommodated in the recesses 140 and 240 formed by the partition wall 130.

When the organic electroluminescent display device is formed through the above process, the organic electroluminescent display device is completed by finally forming a metal electrode (not shown), and when an electric current flows between the transparent electrode and the metal electrode, The light emitting layer emits light to operate.

As described above, when the organic light emitting layer of the organic light emitting display device is formed using the metal masks according to the first and second embodiments of the present invention, the first to third protrusions 130a to 130c and 230a to 230c are formed. Since the distance between the metal masks 110 and 210 and the substrate 300 can be kept constant, a spacer formed for depositing an organic light emitting material is conventionally unnecessary. This eliminates the need for an additional process for spacer formation, resulting in significant process cost savings. That is, according to the present invention, since a process for forming a spacer is removed in a two-step process for forming a bank and a spacer necessary for forming a conventional organic light emitting layer, there is an effect of reducing half or more of the cost incurred due to the process. .

In addition, since the organic light emitting material in the neighboring pixel cell area is prevented from invading by the first to third protrusions 130a to 130c and 230a to 230c, misalignment due to other color invasion can be prevented. have. In addition, since the center is well supported by the first to third protrusions 130a to 130c and 230a to 230c when the metal mask is in contact with the substrate when the organic light emitting material is deposited, the effect of minimizing dark spots due to the imaging is also obtained. do. When the reduction of the defective rate according to the present invention was tested, the alignment defects generated when the organic light emitting layer was formed by the conventional metal mask was reduced from about 6.5% to almost 0%, and the dark spot defect rate was about 3.2% at about 6.4%. It was about 50% more effective than the conventional degree.

In the above description of the embodiments of the present invention, the metal mask is applied to the deposition process for forming the organic light emitting layer of the active matrix organic electroluminescent display device by way of example, but those skilled in the art will use the technical principles of the metal mask according to the present invention. In order to prevent defects caused by contact between the substrate and the metal mask in other flat panel display devices and semiconductor processes, the present invention can be modified, changed, and improved. Accordingly, the scope of the present invention is not limited thereto, and various modifications, modifications, and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also within the scope of the present invention.

1 is a plan view of a slit metal mask according to a first embodiment of the present invention,

2A and 2B are a plan view and a cross-sectional view showing an enlarged portion A shown in FIG. 1;

3 is a plan view of a slotted metal mask according to a second embodiment of the present invention;

4A and 4B are a plan view and a cross-sectional view showing an enlarged view of part B shown in FIG. 3;

5A through 5D are cross-sectional views illustrating a process of manufacturing an active matrix organic electroluminescent display device using a metal mask according to an embodiment of the present invention.

Claims (8)

A plurality of recesses and openings formed at predetermined intervals in a predetermined position; And a plurality of partitions defining the recesses and the openings. The method of claim 1, Each of the plurality of partition walls includes a first protrusion, a second protrusion, and a third protrusion of a line shape, The concave portion includes a first concave portion and a second concave portion having a line shape. The method of claim 2, The first concave portion is formed by the first protrusion and the second protrusion of each partition wall, And the second recess is formed by a second protrusion and a third protrusion of the partition wall. The method of claim 2, The opening is, First projections of the partition walls; Third protrusions of the partition wall adjacent to each of the partition walls; And The metal mask, characterized in that formed by the connecting portion arranged at a predetermined interval so as to connect the first projection of each partition wall and the third projection of the neighboring partition wall. The method of claim 2, And the opening is linearly formed by a first partition of each partition and a third partition of a partition adjacent to each partition. The method of claim 3, wherein The width and depth of the first concave portion, the metal mask, characterized in that the same as the width and depth of the second concave portion. The method of claim 6, The width of the opening is the same as the width of the first recessed metal mask. An organic electroluminescent display device manufactured using the metal mask according to any one of claims 1 to 7.

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