KR100595170B1 - full-color organic electroluminescence display panel and method for fabricating the same - Google Patents

Abstract

The present invention relates to a full-color organic EL display panel and a method of manufacturing the same. An electrically insulating partition wall is formed between the second electrode bands to electrically insulate the second electrode bands. By forming the auxiliary barrier ribs thicker than the electrically insulating barrier ribs in the region, the electrically insulating barrier ribs may be prevented from being damaged by vibration of the shadow mask, thereby improving the electrical insulation effect between pixels.

Secondary bulkhead

Description

Full-color organic electroluminescence display panel and method for fabricating the same

1A and 1B show a general strip type and delta type full-color organic EL display panel and shadow masks used in their fabrication;

2A to 2M are process cross-sectional views showing a manufacturing process of a full-color organic EL display panel according to the present invention.

3 shows a strip-type auxiliary bulkhead according to the present invention.

4A and 4B show the shape of an electrically insulating bulkhead used in the present invention.

Explanation of symbols for main parts of the drawings

1: transparent substrate 2-1,2-2: first electrode

3-1,3-2: Pad 4-1,4-2: Auxiliary electrode

5: auxiliary bulkhead 6: buffer layer

7; Electrically insulating bulkhead 8: organic EL layer

9: second electrode

The present invention relates to a display panel, and more particularly, to a full-color organic EL display panel and a manufacturing method thereof.

Recently, as the size of the display device increases, the demand for a flat panel display panel with less space is increasing, and as one of such flat panel display panels, an organic EL display panel is attracting attention.

The organic EL display panel is very thin, can be addressed in a matrix form, and can be driven at a low voltage of 15V or less.

There are various methods for realizing full-color in making such an organic EL display panel. Among them, the most efficient luminous efficiency is a method using a shadow mask.

As a method of using a shadow mask, as illustrated in FIGS. 1A and 1B, there are a strip method and a delta method.

The shadow mask is a method of depositing R, G and B light emitting materials separately.

That is, the transparent first electrode strips are formed on the transparent substrate, and the barrier ribs are formed in advance to form the second electrode strips thereon, and then a red emitting material is formed using a shadow mask as shown in FIGS. 1A and 1B. Form a layer.

Next, as in the red light emitting material layer forming method, the green light emitting material layer and the blue light emitting material layer are formed while moving side by side by using another shadow mask, and then the second electrode material is deposited on the front surface. A full-color organic EL display panel is fabricated by forming the second electrode strip in the light emitting region.

However, in the method using the shadow mask, the strip type shadow mask as shown in FIG. 1A and the delta type shadow mask as shown in FIG. 1B are likely to be drawn down due to the patterns formed in the mask.

In particular, in the case of a strip type shadow mask as shown in FIG. 1A, since long patterns having a rectangular shape are formed, they are more likely to be struck.

Therefore, in order to prevent sagging of the shadow mask, it is inconvenient to give the mask a tensile force.

In addition, even if a sagging shadow mask is used, the metal strips of the mask may vibrate even under a slight impact, damaging the partition walls of the panel.

The reason for damaging the bulkhead is that the gap between the shadow mask and the panel is very narrow, and the bulkheads at the highest position among the layers formed in the panel are damaged by the vibration of the mask.

Such damage to the partition causes a short to occur between pixels in forming the second electrode.

If the distance between the shadow mask and the panel is increased to prevent damage to the partition, the shadow effect of the deposited material is serious.

Therefore, the RGB material to be deposited is not formed correctly at the desired position due to the shadow effect, and colors are not good because the colors are mixed.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object thereof is to provide a full-color organic EL display panel and a method of manufacturing the same, which can prevent damage to a partition wall despite the vibration of a shadow mask.

Another object of the present invention is to reduce the resistance of the first electrode strip.

A feature of the full-color organic EL display panel according to the present invention is that in the full-color organic EL display panel each having a light emitting area at a position where the first electrode bands and the second electrode bands cross each other perpendicularly, each second electrode Electrical insulating partitions formed between the bands to electrically insulate the second electrode strips, and auxiliary partitions formed in a region other than the light emitting region between each electrical insulating partition and formed thicker than the electrical insulating partitions. It is.

A feature of the full-color organic EL display panel manufacturing method according to the present invention is a transparent full-color organic EL display panel manufacturing method having a light emitting region at a position where the first electrode bands and the second electrode bands cross each other perpendicularly. A first step of forming a plurality of first electrode strips having a predetermined distance on the substrate, a second step of forming auxiliary partitions having a predetermined distance in a region other than the light emitting region, and a buffer layer formed on a front surface of the auxiliary partition A third step, a fourth step of forming electrically insulating partitions thinner than the thickness of the auxiliary partition wall in a direction perpendicular to the first electrode bands in a region other than the light emitting region between the auxiliary partition walls, and each light emission using a shadow mask A fifth step of forming an organic light emitting layer that emits light corresponding to the region; and depositing an electrode material on the entire surface including the organic light emitting layer to form a light emitting region. Of the can makin made of a sixth step, the seventh step of forming a protective film on the front, including the second electrode strip to form the second electrode strip.

The full-color organic EL display panel and its manufacturing method according to the present invention having the above characteristics will be described with reference to the accompanying drawings.

First, the concept of the present invention is to prevent the damage of the electrical insulating partition due to the vibration of the shadow mask by forming the auxiliary partitions thicker than the electrically insulating partition wall, and also to form a secondary electrode to overlap the first electrode edge to reduce the resistance To reduce.

2A to 2M are cross-sectional views showing a manufacturing process of a full-color organic EL display panel according to the present invention. As shown in FIG. 2A, first, a first electrode 2 made of a transparent material on a transparent substrate 1 is shown. -1,2-1) strips, the pad 3-1 of the first electrode and the pad 3-2 of the second electrode are formed.

In this case, in the case of the delta type, as shown in FIG. 2A, a portion formed in the light emitting region of the first electrode is formed in a polygonal shape having three or more angles (2-1), and a portion formed in the region not emitting light. Is formed in a line shape narrower than a portion formed in the light emitting area (2-2) to connect the first electrodes 2-1 having a polygonal shape.

The first electrode 2-1 formed in the light emitting region should be formed in a delta or triangle structure such as a, b, and c.

That is, the first and third first electrode strips are positioned on the same line, and the second first electrode strips are formed to be slightly displaced.

In the case of a strip type, a strip may be formed as shown in FIG. 2B.

Subsequently, as shown in FIG. 2C, auxiliary electrodes 4-1 and 4-2 are formed to partially overlap the edges of the first electrodes in order to reduce resistance of the first electrodes.

FIG. 2D is an enlarged view of region A of FIG. 2C, and not only the first electrode 2-2 of the non-light emitting region but also the auxiliary electrodes 4-1 and 4 around the first electrode 2-1 of the light emitting region. -2) is very effective in reducing the resistance.

Here, the material used for the auxiliary electrodes 4-1 and 4-2 may be made of a metal having a relatively lower resistance than ITO, which is a material of the first electrode.

For example, Cr, Al, Cu, W, Au, Ni, Ag and the like.

The surface where the auxiliary electrode contacts the first electrode may be represented by a as shown in FIG. 2D, where a> 0.

Then, as shown in FIG. 2E, the auxiliary barrier rib 5 is formed between the emission regions in a direction perpendicular to the first electrodes, and then the buffer layer 6 is formed on the front surface as shown in FIG. 2F. As shown in FIG. 2G, the electrically insulating partitions 7 are formed in a region other than the light emitting region between the auxiliary partitions 5.

This partition wall forming process is the most important process in the present invention, which will be described in more detail with reference to FIGS. 2I and 2J.

Like the electrical insulating partition 7, the auxiliary partition 5 plays a role for electrical insulation between pixels. The main role is to form an electrical insulating partition due to vibration of the shadow mask when forming RGB using the shadow mask in a post-process. 7) prevents damage.

Therefore, in order to prevent the damage of the electrically insulating partition 7, the thickness of the auxiliary partition 5 must be thicker than that of the electrically insulating partition 7, and any position except the position at which the electrically insulating partition 7 is to be formed. It may be formed on.

For example, the delta type may be formed in the same direction between the electrically insulating partition 7 and the electrically insulating partition as in FIGS. 2E, 2F, and 2G. Likewise, the first electrode between the electrically insulating partitions 7 is suitable.

Here, in the case of a strip type, the auxiliary partition 5 is formed in a direction perpendicular to the electrically insulating partition 7 as shown in FIG. 3.

In addition, although the auxiliary partition 5 may be formed before forming the buffer layer 6, you may form the auxiliary partition 5 after forming the buffer layer 6 first.

As shown in FIG. 2J, the area in which the buffer layer 6 covers the first electrode 2-1 may be represented by b, where b> 0.

The material used for the auxiliary partition 5 and the buffer layer 6 may be an insulator, regardless of whether it is an inorganic material or an organic material.

In particular, in the case of inorganic materials, oxides and nitrides may be used, and inorganic materials dissolved in solvents in a spinable manner may be used.

In the case of organic materials, a polymer is more advantageous than a single molecule, and photoresist, polyimide, and polyolefin, which are often used in a photo process, are suitable.

In addition, the electrically insulating partition wall 7 is formed using a negative photoresist as shown in FIG. 4A, or is formed of a positive photoresist having an over-hang as shown in FIG. 4B.

As shown in FIG. 2K, an organic light emitting layer 8-1 (light emitting layer, electron transport layer, hole transport layer, etc.) emitting red light using a shadow mask as shown in FIGS. 1A and 1B is used. 2), an organic light emitting layer 8-2 emitting green light using another shadow mask, and an organic light emitting layer 8-3 emitting blue light using another shadow mask. ) Is deposited.

At this time, among the organic light emitting layers emitting red, green, and blue light, the materials 8 which are commonly inputted are used once by using a blank mask that can deposit the entire light emitting area without using a shadow mask. It is good to deposit on.

In addition, in the case of the delta type, the organic light emitting layer emitting red, green, and blue light has a triangular structure, and the organic light emitting layer emitting red, green, blue light, which is repeated next to it, has an inverted triangle structure.

Subsequently, as illustrated in FIG. 2M, the pad 3 of the second electrode 9 formed of a material of the second electrode 9 made of any one of Mg-Ag alloy, Al, and other conductive materials is wider than the entire light emitting region, and formed in advance. The second electrode 9 bands are formed between the electrically insulating partitions 7 by overlapping with -2).

Then, a protective film layer (oxygen adsorption layer, moisture adsorption layer, etc.) is formed thereon, and encapsulation is performed to complete the full-color organic EL display panel.

As described above, in the present invention, the secondary insulating wall is formed thicker (higher) than the electrical insulating partition to prevent the electrical insulating partition from being damaged due to the vibration of the shadow mask and to prevent electrical short circuit between pixels. The electrical insulation effect between pixels can be improved.

The full-color organic EL display panel and the manufacturing method thereof according to the present invention have the following effects.

The present invention makes it possible to manufacture a full-color organic EL display panel more efficiently by forming an auxiliary partition thicker than an electrically insulating partition wall, which is a problem in using a shadow mask in making a full-color organic EL display panel.

Claims (14)

A full-color organic EL display panel having a light emitting area at a position where the first electrode bands and the second electrode bands cross each other perpendicularly, respectively. Electrically insulating barrier ribs formed between the second electrode strips to electrically insulate the second electrode strips; And an auxiliary barrier rib formed in a region other than the light emitting region between each of the electrically insulating barrier ribs, the auxiliary barrier ribs being formed thicker than the electrically insulating barrier rib. The method of claim 1, wherein the electrically insulating partitions are formed in a direction perpendicular to the first electrode strips, the auxiliary partitions are formed in a direction perpendicular to the first electrode strips or formed in the same direction. Full-color organic EL display panel. The full-color organic EL display panel according to claim 1, wherein a buffer layer is formed below the electrically insulating partition wall, and a buffer layer is formed on at least one of the upper and lower portions of the auxiliary partition wall. The full-color organic EL display panel according to claim 1, wherein an auxiliary electrode is partially overlapped at an edge of each of the first electrode strips. 2. The full-color organic EL display panel according to claim 1, wherein the first electrode is formed wide in the light emitting region and narrow in the non-light emitting region. The full-color organic EL display panel according to claim 1, wherein the first electrode of each light emitting area is a polygon or circle shape having three or more angles. 2. The full-color organic EL display panel according to claim 1, wherein the light emitting region arrangement structure is any one of a delta and a strip. In the method for manufacturing a full-color organic EL display panel having a light emitting region at a position where the first electrode bands and the second electrode bands cross each other perpendicularly, A first step of forming a plurality of first electrode bands on the transparent substrate; A second step of forming auxiliary barrier ribs in a region other than the light emitting region; A third step of forming a buffer layer on the entire surface including the auxiliary partition wall; A fourth step of forming electrically insulating partitions thinner than a thickness of the auxiliary partition in a direction perpendicular to the first electrode bands in a region other than the light emitting region between the auxiliary partitions; A fifth step of forming an organic light emitting layer that emits light corresponding to each light emitting area by using a shadow mask; A sixth step of forming a plurality of second electrode bands in the emission region by depositing an electrode material on the entire surface including the organic light emitting layer; And a seventh step of forming a protective film on the entire surface including the second electrode strips. 9. The method of manufacturing a full-color organic EL display panel according to claim 8, wherein the buffer layer of the third step is formed before the second step. The method of manufacturing a full-color organic EL display panel according to claim 8, wherein the auxiliary partition wall is an insulator selected from inorganic and organic materials. The method of manufacturing a full-color organic EL display panel according to claim 10, wherein the insulator is any one of an oxide, a nitride, an inorganic substance dissolved in a solvent, a photoresist, a polyimide, and a polyolefin. The method of manufacturing a full-color organic EL display panel according to claim 8, wherein the auxiliary partition wall is formed in the same direction as the electrically insulating partition wall or in a direction perpendicular to the electrically insulating partition wall. The method of manufacturing a full-color organic EL display panel according to claim 8, further comprising: after the first step, forming an auxiliary electrode such that a part of the second electrode strip overlaps with an edge of the first electrode strip. The method of claim 13, wherein the auxiliary electrode is formed of any one of Cr, Al, Cu, W, Au, Ni, and Ag.

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