KR101074384B1 - A electro-Luminescence display device and a method for fabricating the same - Google Patents

Abstract

The present invention relates to an organic electroluminescent display device which can reduce the number of processes by simultaneously performing an etching process and a surface treatment process, comprising: a substrate having a plurality of pixel regions; A first electrode layer formed on the front surface of the substrate including the pixel areas; An organic light emitting layer formed on the first electrode layer corresponding to the pixel region; A second electrode layer formed on the organic light emitting layer; A plurality of partition walls surrounding a circumference of each pixel area and formed on the first electrode layer; Protrusions protruding from one side of each of the barrier ribs into spaces between the barrier ribs and facing the first electrode layer at predetermined intervals; A bus line formed on a first electrode layer in a space provided between the partition walls and whose edges are covered by protrusions of the partition walls; And a dummy layer formed in a space provided between the edge of the bus line and the protrusion and formed of a combination of silane (SiH 4) and ammonia (NH 3), wherein the proportion of the ammonia is at least two times greater than that of the silane. It is configured to include.

Organic light emitting display, barrier rib, organic light emitting layer, wet etching, plasma, undercut

Description

A electro-luminescent display device and a method for fabricating the same

1 is a block diagram of an upper substrate of a conventional organic light emitting display device

2 is a cross-sectional view taken along line II of FIG. 1.

3A to 3H are cross-sectional views illustrating a method of manufacturing a conventional organic light emitting display device.

4 is a configuration diagram of an upper substrate of an organic light emitting display device according to an embodiment of the present invention.

FIG. 5 is a cross-sectional view taken along line II-II of FIG. 4.

6 is a view for explaining the depth of the undercut of the dummy layer according to the composition ratio of silane and ammonia.

7A to 7G are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to an exemplary embodiment of the present invention.

8 is a flowchart illustrating a manufacturing process of an organic light emitting display device according to an embodiment of the present invention.

* Explanation of symbols on the main parts of the drawings

401 substrate 405 partition wall                 

403: bus line

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting display device, and more particularly, to an organic light emitting display device and a method of manufacturing the same, which can reduce the number of processes by simultaneously performing an etching and surface treatment process.

Recently, various flat panel displays have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes. Such flat panel displays include a liquid crystal display, a field emission display, a plasma display panel, an electroluminescence display, and the like.

Recently, studies are being actively conducted to increase the display quality of such a flat panel display device and to attempt to make a large screen. Among them, the electroluminescent display device is a self-luminous element emitting light by itself. The electroluminescent display displays a video image by exciting a fluorescent material using carriers such as electrons and holes. The electroluminescent display is largely divided into an inorganic electroluminescent display and an organic electroluminescent display according to the material used. The organic electroluminescent display device is driven at a lower voltage of about 5 to 20 volts than the inorganic electroluminescent display device requiring a high voltage of 100 to 200 volts, thereby allowing direct current low voltage driving. In addition, the organic electroluminescent display has excellent features such as wide viewing angle, high-speed response, high contrast ratio, and the like, such as pixels of graphic displays, television image displays, and surface light sources. It can be used as a pixel, and is suitable as a next-generation flat panel display because it is thin, light, and has good color.

On the other hand, a passive matrix type (Passive matrix type) that does not have a separate thin film transistor is mainly used as a driving method of such an organic light emitting display device.

However, since the passive matrix method has many limited factors such as resolution, power consumption, and lifespan, active matrix type electroluminescent display devices for manufacturing next-generation displays requiring high resolution and large screens have been researched and developed.

Hereinafter, a conventional organic light emitting display device will be described in detail with reference to the accompanying drawings.

1 is a block diagram of an upper substrate of a conventional organic light emitting display device, and FIG. 2 is a cross-sectional view taken along line I to I of FIG. 1.

As illustrated in FIGS. 1 and 2, the upper substrate 101 of the conventional organic light emitting display device is defined as a plurality of pixel regions P arranged in a matrix form. The first electrode layer 102 is formed on the entire surface of the substrate 101. The first electrode layer 102 is a hole injection electrode for injecting holes into the organic emission layer 106.

In addition, a plurality of partitions 105 are formed on the first electrode layer 102. The partitions 105 are used to isolate the pixel areas P from each other. For this purpose, the partitions 105 surround a circumference of the pixel area P. Here, since the partitions 105 are spaced apart from each other by a predetermined distance, a space 109 is formed between the partitions 105.

In addition, one side of the barrier rib 105 is formed with a protrusion 115 integrally formed with the barrier rib 105, and the protrusion 115 faces the space 109 formed between the barrier ribs 105. It protrudes. Therefore, the cross section consisting of the partition wall 105 and the protrusion 115 has an approximately '-' shape. Here, since the protrusions 115 of the partitions 105 protrude toward the space 109 so as to face each other, the space 109 is covered by a portion of the protrusion 115.

In addition, a bus line 103 is formed in the space 109. The bus line 103 has a lattice shape as a whole.

A dummy layer 104 is formed in the space 109 between the edge of the bus line 103 and the protrusion 115. In this case, an interval between the dummy layers 104 may be greater than an interval between the protrusions 115. That is, the area of the bus line 103 covered by the protrusion 115 is larger than the area of the bus line 103 covered by the dummy layer 104. In other words, the protrusion 115 protrudes toward the central portion of the bus line 103 more than the dummy layer 104. Therefore, a step occurs between the dummy layer 104 and the protrusion 115.

An organic emission layer 106 is formed on the first electrode layer 102 of the pixel region P, and a second electrode layer 107 is formed on the organic emission layer 106. The second electrode layer 107 is an electron injection electrode for injecting electrons into the organic emission layer 106.

Meanwhile, the second electrode layer 107 is disconnected between the dummy layer 104 and the protrusion 115 by the step between the dummy layer 104 and the protrusion 115. Therefore, the second electrode layer 107 is formed separately from each other in the pixel region P. Here, reference numeral 108 in FIG. 2 is a layer separated from the second electrode layer 107 by the step.

In addition, although not shown in the drawings, the conventional organic light emitting display device further includes a lower substrate facing the upper substrate 101 configured as described above. The lower substrate is also defined as a plurality of pixel regions, and each pixel region includes a thin film transistor (switching element and driving element). Here, the upper substrate 101 and the lower substrate are bonded by a sealant, so that the drain electrode of the driving device provided on the lower substrate is connected to the second electrode layer 107 of the upper substrate 101. .

Meanwhile, the manufacturing method of the conventional organic light emitting display device configured as described above will be described in detail.

3A to 3H are cross-sectional views illustrating a method of manufacturing a conventional organic light emitting display device.

First, as shown in FIG. 3A, a substrate 101 having a plurality of pixel regions P arranged in a matrix form is prepared, and a transparent conductive surface is formed on the entire surface of the substrate 101 including the pixel regions P. FIG. Indium Tin Oxide (ITO) is deposited to form a first electrode layer 102.

Subsequently, as illustrated in FIG. 3B, a metal having excellent electrical conductivity, such as copper, is deposited on the entire surface of the substrate 101 including the first electrode layer 102, and patterned through a photo and etching process. The bus line 103 is formed on the first electrode layer 102. In this case, the bus line 103 is formed on the first electrode layer 102 except for a portion except the pixel region P and a portion in which the partition 105 to be described later is formed.

Subsequently, as illustrated in FIG. 3C, silicon oxide (SiO 2) is deposited on the entire surface of the substrate 101 including the bus line 103, and patterned through photo and etching processes to form a dummy layer 104. To form. In this case, the dummy layer 104 is formed on the bus line 103 so as to completely cover the bus line 103.

Therefore, the dummy layer 104 also has the same shape as the bus line 103.

Subsequently, as illustrated in FIG. 3D, polyimide is deposited on the entire surface of the substrate 101 including the dummy layer 104, and patterned through photo and etching processes to form a polyimide on the first electrode layer 102. At the same time as forming the partition wall 105, a protrusion 115 protruding from one side of the partition wall 105 is formed. In this case, the partition wall 105 is formed on the first electrode layer 102 to surround the edge of the pixel region P, and the protrusion 115 protrudes from one side of the partition wall 105 to form the dummy layer. It is formed to cover the edge of the 104. Therefore, only the center of the dummy layer 104 is exposed to the outside.

Next, as illustrated in FIG. 3E, the center portion of the dummy layer 104 exposed by using the protrusion 115 as a mask is etched. At this time, the etching is excessively performed so that an undercut occurs in the dummy layer 104. After the etching operation is completed, a space 109 is formed between the partitions 105 to expose the first electrode layer 102.

Here, in the etching operation, a wet etching method is used, which is a property of the wet etching (that is, since the wet etching uses a solution, the etching proceeds isotropically, and thus, the mask (here, the protrusion ( Undercut phenomenon occurs in which a part of the edge of the dummy layer 104 covered by the same) is etched together.

Subsequently, when the etching operation is completed, as illustrated in FIG. 3F, the entire surface of the substrate 101 including the first electrode layer 102, the bus line 103, and the partition wall 105 is plasma treated. Then, the surface of the first electrode layer 102 exposed to the plasma is hydrophilic, and the surfaces of the partition wall 105 and the bus line 103 exposed to the plasma are hydrophobic. do.

Next, as illustrated in FIG. 3G, an organic light emitting layer is formed by applying a light emitting solution onto the first electrode layer 102 positioned in each pixel region P using an inkjet coating apparatus (not shown). Form 106. The color of the light emitting solution represents any one of R, G, and B.

Here, since the surface of the first electrode layer 102 is hydrophilized by the plasma treatment, the adhesion between the light emitting solution and the surface of the first electrode layer 102 is further improved. On the other hand, since the surface of the second partition wall 105 is hydrophobized by the plasma treatment, the adhesion between the light emitting solution and the surface of the partition wall 105 and the surface of the light emitting solution and the bus line 103 Adhesion is weakened. Accordingly, the organic emission layer 106 may be selectively formed only on the first electrode layer 102 positioned in each pixel region P. FIG.

Subsequently, as illustrated in FIG. 3H, a metal layer such as potassium, magnesium, or aluminum is deposited on the entire surface of the substrate 101 including the organic light emitting layer 106 to form a second electrode layer 107 serving as a cathode electrode. do. In this case, the second electrode layer 107 is separated between the pixel areas P. FIG. That is, the second electrode layer 107 is separated from the space 109 located between the partition walls 105 by the step between the dummy layer 104 and the protrusion 115.

Therefore, each pixel area P has an independent second electrode layer 107.

However, the conventional organic light emitting display device has the following problems.

That is, in the conventional organic light emitting display device, as described above, the process of forming the first electrode layer 102, the process of forming the bus line 103, the process of forming the dummy layer 104, the partition 105, and the protrusion ( Since the process of forming 115, the process of etching the dummy layer 104, the process of surface treatment, the process of forming the organic light emitting layer 106, and the process of forming the second electrode layer 107 are required, There was a problem that takes a long time.

In addition, in the wet etching process, since a solution chemical is used, there is a problem that a separate treatment facility must be provided in order to treat the remaining waste water using the same.

The present invention has been made to solve the above problems, by using the dry etching does not cause the problem of wastewater treatment, and at the same time proceed to the surface treatment process and the etching of the dummy layer, it is possible to shorten the process time An object of the present invention is to provide an organic light emitting display device and a method of manufacturing the same.

An organic light emitting display device according to the present invention for achieving the above object comprises a substrate having a plurality of pixel areas; A first electrode layer formed on the front surface of the substrate including the pixel areas; An organic light emitting layer formed on the first electrode layer corresponding to the pixel region; A second electrode layer formed on the organic light emitting layer; A plurality of partition walls surrounding a circumference of each pixel area and formed on the first electrode layer; Protrusions protruding from one side of each of the barrier ribs into spaces between the barrier ribs and facing the first electrode layer at predetermined intervals; A bus line formed on a first electrode layer in a space provided between the partition walls and whose edges are covered by protrusions of the partition walls; And a dummy layer formed in a space provided between the edge of the bus line and the protrusion and formed of a combination of silane (SiH 4) and ammonia (NH 3), wherein the proportion of the ammonia is at least two times greater than that of the silane. It is characterized by including the configuration.

In addition, the manufacturing method of the organic light emitting display device according to the present invention for achieving the above object comprises the steps of preparing a substrate having a plurality of pixel regions; Forming a first electrode layer on an entire surface of the substrate including the pixel regions; Forming a bus line on the first electrode layer except for the pixel area; Forming a dummy layer on the bus line, the dummy layer comprising a combination of silane (SiH 4) and ammonia (NH 3), wherein the proportion of the ammonia is at least twice as large as that of the silane; Forming a partition on the first electrode layer to surround the pixel area, and protruding from one side of the partition to form a protrusion covering an edge of the dummy layer; Etching the central portion of the dummy layer exposed by using the barrier rib and the protrusion as a mask, and forming a space for exposing the first electrode layer by etching the dummy layer so as to undercut, the first electrode layer, the partition, And surface treating the busline; Forming an organic emission layer on a first electrode layer in which the pixel region is located; And forming a second electrode layer on the organic light emitting layer.

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

4 is a configuration diagram of an upper substrate of an organic light emitting display device according to an exemplary embodiment of the present invention, and FIG. 5 is a cross-sectional view taken along line II to II of FIG. 4.

As illustrated in FIGS. 4 and 5, the upper substrate 401 of the electroluminescent display according to the exemplary embodiment of the present invention is defined as a plurality of pixel regions P arranged in a matrix form. The first electrode layer 402 is formed on the entire surface of the substrate 401 including (P). The first electrode layer 402 is a hole injection electrode for injecting holes into the organic emission layer 406.                     

In addition, a plurality of partitions 405 are formed on the first electrode layer 402. Each of the barrier ribs 405 isolates the pixel regions P from each other. For this purpose, the barrier ribs 405 surround a circumference of the pixel regions P. FIG. Here, since the partitions 405 are spaced apart from each other by a predetermined distance, a space 409 is formed between the partitions 405.

In addition, one side of the barrier rib 405 is formed with a protrusion 415 integrally formed with the barrier rib 405, and the protrusion 415 faces the space 409 formed between the barrier ribs 405. It protrudes. Therefore, the cross section consisting of the partition wall 405 and the protrusion 415 has an approximately '-' shape. Here, since the protrusions 415 of each of the partition walls 405 protrude toward the space 409 to face each other, the space 409 is covered by a predetermined portion by the protrusions 415.

In addition, a bus line 403 is formed in the space 409. The bus line 403 has a grid shape as a whole.

In addition, a dummy layer 404 is formed in the space 409 between the edge of the bus line 403 and the protrusion 415. In this case, the gap between the dummy layers 404 is wider than the gap between the protrusions 415. That is, the area of the bus line 403 covered by the protrusion 415 is larger than the area of the bus line 403 covered by the dummy layer 404. In other words, the protrusion 415 protrudes further toward the center of the bus line 403 than the dummy layer 404. Therefore, a step occurs between the dummy layer 404 and the protrusion 415.                     

Here, the dummy layer 404 is made of silicon nitride (SiNx), and the silicon nitride is made of a combination of ammonia (NH 3) and silane (SiH 4). On the other hand, the ratio of the ammonia is at least two times or more than the ratio of the silane. Due to such a ratio, the dummy layer 404 may be undercut by dry etching instead of conventional wet etching. In addition, when the plasma is used during the dry etching, the etching process and the surface treatment process may be simultaneously performed. This will be described in more detail later.

An organic emission layer 406 is formed on the first electrode layer 402 of the pixel region P, and a second electrode layer 407 is formed on the organic emission layer 406. The second electrode layer 407 is an electron injection electrode for injecting electrons into the organic emission layer 406.

Meanwhile, the second electrode layer 407 is disconnected between the dummy layer 404 and the protrusion 415 due to the step between the dummy layer 404 and the protrusion 415. Therefore, the second electrode layer 407 is formed separately from each other in the pixel region P. FIG. 5 is a layer separated from the second electrode layer 407 by the step.

In addition, although not shown in the drawings, the conventional organic light emitting display device further includes a lower substrate facing the upper substrate 401 configured as described above. The lower substrate is also defined as a plurality of pixel regions, and each pixel region includes a thin film transistor (switching element and driving element). Here, the upper substrate 401 and the lower substrate are bonded by a sealant, so that the drain electrode of the driving device provided on the lower substrate is connected to the second electrode layer 407 of the upper substrate 401. .                     

Hereinafter, the dummy layer 404 made of silicon nitride (SiNx) will be described in more detail.

6 is a view for explaining the depth of the undercut of the dummy layer according to the composition ratio of silane and ammonia.

First, silicon nitride used as a material of the dummy layer 404 is generated by a chemical reaction between silane (SiH 4) and ammonia (NH 3), as described above, wherein, depending on the composition ratio of the silane and ammonia, The depth d of the undercut formed in the dummy layer 404 is changed. That is, the silicon nitride is etched by the plasma, wherein the depth of the undercut to be etched depends on the composition ratio of the silane and ammonia.

Specifically, as shown in (a) of FIG. 6, when the composition ratio of silane and ammonia is 1: 3, the depth of the undercut of the dummy layer 404 is about 0.265 um, and FIG. 6 (b). As shown in), when the composition ratio of silane and ammonia is 1: 4, the depth of the undercut of the first partition 404 is about 0.929 um, as shown in (c) of FIG. When the composition ratio of silane and ammonia is 1: 6, the depth of the undercut of the first partition 404 is about 1.641 um.

That is, when the composition ratio of the ammonia is at least twice as large as that of the silane, when the dummy layer 404 is etched using plasma, an undercut may occur in the dummy layer 404.

Hereinafter, a manufacturing method of an organic light emitting display device according to an exemplary embodiment of the present invention configured as described above will be described in detail.                     

7A to 7G are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to an embodiment of the present invention, and FIG. 8 is a flowchart illustrating a manufacturing process of an organic light emitting display device according to an embodiment of the present invention. to be.

First, as shown in FIG. 7A, a substrate 401 having a plurality of pixel regions P arranged in a matrix form is prepared, and a transparent conductive surface is formed on the entire surface of the substrate 401 including the pixel regions P. FIG. Indium Tin Oxide (ITO) is deposited to form a first electrode layer 402 (S1).

Subsequently, as illustrated in FIG. 7B, a metal having excellent electrical conductivity such as copper is deposited on the entire surface of the substrate 401 including the first electrode layer 402, and patterned through a photo and etching process. The bus line 403 is formed on the first electrode layer 402 (S2). In this case, the bus line 403 is formed on the first electrode layer 402 except for a portion except for the pixel region P and a portion in which the partition wall 405 to be described later is formed.

Here, the bus line 403 has a grid shape as a whole.

Subsequently, as illustrated in FIG. 7C, silicon oxide (SiO 2) is deposited on the entire surface of the substrate 401 including the bus line 403, and patterned through photo and etching processes to form a dummy layer 404. To form (S3). In this case, the dummy layer 404 is formed on the bus line 403 so as to completely cover the bus line 403.

Therefore, the dummy layer 404 also has the same shape as the bus line 403.

Subsequently, as illustrated in FIG. 7D, polyimide is deposited on the entire surface of the substrate 401 including the dummy layer 404, and patterned through photo and etching processes to form a polyimide on the first electrode layer 402. The barrier rib 405 is formed at the same time, and the protrusion 415 protruding from one side of the barrier rib 405 is formed (S4). In this case, the barrier rib 405 is formed on the first electrode layer 402 so as to surround the edge of the pixel region P, and the protrusion 415 protrudes from one side of the barrier rib 405 to form the dummy layer. It is formed to cover the edge of the (404). Therefore, only the center of the dummy layer 404 is exposed to the outside.

Next, as shown in FIG. 7E, the center portion of the dummy layer 404 exposed using the protrusion 415 as a mask is etched. At this time, the etching is excessively performed so that an undercut occurs in the dummy layer 404. After the etching operation is completed, a space 409 exposing the first electrode layer 402 is formed between the partition walls 405.

However, dry etching is used in the etching process, and the gas used in the dry etching uses plasma.

In this case, since the dummy layer 404 is made of a silicon nitride material having the composition ratio as described above, when the dummy layer 404 is etched using the plasma, an undercut occurs in the dummy layer 404. .

Here, the plasma is applied to the surface of the first electrode layer 402, the bus line 403, and the partition wall 405 while etching the dummy layer 404. Is hydrophilized and the surfaces of the bus line 403 and the partition wall 405 are hydrophobized.                     

As described above, in the present invention, the dummy layer 404 is formed of silicon nitride having the composition ratio as described above, so that the conventional wet etching process may be replaced by dry etching, and by using the plasma during the dry etching process, the etching process may be performed. And surface treatment can be carried out simultaneously (S5).

Next, as illustrated in FIG. 7F, an organic light emitting layer is formed by applying a light emitting solution onto the first electrode layer 402 located in each pixel region P using an inkjet coating apparatus (not shown). 406 is formed (S6). The color of the light emitting solution represents any one of R, G, and B.

Here, since the surface of the first electrode layer 402 is hydrophilized by the plasma treatment, the adhesion between the light emitting solution and the surface of the first electrode layer 402 is further improved. On the other hand, since the surface of the partition wall 405 has been hydrophobized by the plasma treatment, the adhesion between the light emitting solution and the surface of the partition wall 405 and the adhesion between the light emitting solution and the surface of the bus line 403. This is weakened. Therefore, the organic light emitting layer 406 may be selectively formed only on the first electrode layer 402 located in each pixel region P. FIG.

Subsequently, as illustrated in FIG. 7G, a metal layer such as potassium, magnesium, or aluminum is deposited on the entire surface of the substrate 401 including the organic light emitting layer 406 to form a second electrode layer 407 which is a cathode electrode. (S7). In this case, the second electrode layer 407 is separated between the pixel areas P. FIG. That is, the second electrode layer 407 is separated from the space 409 located between the partition wall 405 by the step between the dummy layer 404 and the protrusion 415.

Thus, each pixel region P has an independent second electrode layer 407.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of.

As described above, the organic light emitting display device and the manufacturing method thereof according to the present invention have the following effects.

First, in the present invention, by changing the composition of the silicon nitride used in the dummy layer, that is, the composition ratio of silane and ammonia constituting the silicon nitride, an undercut may be generated in the dummy layer even when used in dry etching. Therefore, there is no problem such as wastewater treatment that occurred during conventional wet etching.

Second, by using the plasma during the dry etching, it is possible to proceed with the etching and surface treatment process at the same time. Therefore, process time can be shortened and process yield can be increased accordingly.

Claims (4)

A substrate having a plurality of pixel regions; A first electrode layer formed on the front surface of the substrate including the pixel areas; An organic light emitting layer formed on the first electrode layer corresponding to the pixel region; A second electrode layer formed on the organic light emitting layer; A plurality of partition walls surrounding a circumference of each pixel area and formed on the first electrode layer; Protrusions protruding from the upper sides of the barrier ribs into spaces between the barrier ribs and facing the first electrode layer at predetermined intervals; A bus line formed on a first electrode layer of a space provided between the partition walls, the bus line of which edges are covered by protrusions of the partition walls; And, It is formed in the space provided between the edge of the bus line and the protrusion, and made of a combination of silane (SiH4) and ammonia (NH3), including a dummy layer having a proportion of the ammonia is at least two times or more than the ratio of the silane An organic light emitting display device, characterized in that configured. The method of claim 1, The material used in the etching process for forming the space is an organic electroluminescent display device, characterized in that the plasma. Preparing a substrate having a plurality of pixel regions; Forming a first electrode layer on an entire surface of the substrate including the pixel regions; Forming a bus line on the first electrode layer except for the pixel area; Forming a dummy layer on the bus line, the dummy layer comprising a combination of silane (SiH 4) and ammonia (NH 3), wherein the proportion of the ammonia is at least twice as large as that of the silane; Forming a partition on the first electrode layer to surround the pixel area, and protruding from an upper side of the partition to cover an edge of the dummy layer; Etching the central portion of the dummy layer exposed by using the barrier rib and the protrusion as a mask, and forming a space for exposing the first electrode layer by etching the dummy layer so as to undercut, the first electrode layer, the partition, And surface treating the busline; Forming an organic emission layer on a first electrode layer in which the pixel region is located; And, And forming a second electrode layer on the organic light emitting layer. The method of claim 3, wherein The etching and surface treatment steps of the organic light emitting display device, characterized in that using the plasma.

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