JP2002110345A - Manufacturing method of mask and organic el display element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a mask and an organic EL display element that realizes an organic EL display element having a high fineness by a simple process and with a high yield of manufacture. SOLUTION: A stripe shape shadow mask is used in laminating the organic luminous layers 7R, 7G, 7B. By irradiating a laser beam, the organic luminous layers 7R, 7G, 7B are cut for each picture element. A highly fine display quality which has not been realized when using a lattice shape shadow mask that was difficult to make a fine processing in the conventional method is materialized by using a stripe shape shadow mask that is easy in processing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a mask for manufacturing an organic EL display device and a method for manufacturing an organic EL display device using the same.

[0002]

2. Description of the Related Art Among flat panel display elements widely used in portable devices and the like, liquid crystal display elements are currently the mainstream. However, the liquid crystal display element has some problems as described below.

(1) The viewing angle is narrow. (2) The response speed is slow. (3) Since a backlight is required, power consumption is large. (4) Since a backlight is required, there is a limit in reducing the size of the area other than the pixel display section. Various countermeasures have been considered for these problems.

First, as for the viewing angle, the viewing angle is increased by the pixel division method. However, the number of steps is increased, so that the cost is increased, and it cannot be said that it is an advantageous measure.

Further, it is conceivable to attach a viewing angle compensating plate to the display surface side, but a sufficient viewing angle has not been obtained.

As a means for solving both the viewing angle and the response speed, an MVA (vertical alignment) type display system has been proposed, but there is a problem such as printing.

With respect to power consumption, approaches are being pursued from both a low-voltage driven liquid crystal material and a drive circuit, but all have limitations.

On the other hand, an organic electroluminescence (hereinafter, referred to as an organic EL) display element has recently attracted attention as a display element capable of solving all of the above problems.

Since the organic EL display element is a self-luminous element, it has a wide viewing angle and does not require a backlight, so that it can be made thin and small. In addition, the response speed is three orders of magnitude faster than the liquid crystal.

[0010] Despite being such an excellent display element, the organic organic EL display element has not been readily available on the market because an organic layer having a luminous ability (hereinafter referred to as an organic luminescent layer) is exposed to moisture. It is very sensitive. Therefore, there is a difficulty in the lamination process as a light emitting element, for example, deterioration is caused even by a very small amount of water (about 1 ppm), and the layer is not useful as a display device.

In general, a vapor deposition process using a shadow mask is used in the laminating step of the light emitting element so that the organic light emitting layer is not deteriorated. However, since it is difficult to produce a high-definition shadow mask, it has been difficult to produce a high-definition display element of a liquid crystal display element class.

FIG. 5 shows the structure of a lattice-shaped shadow mask used in the manufacture of a conventional organic EL display device. In order to stack organic light emitting layers for each of R, G, and B on an outer frame (not shown), a plurality of members 21 extending in a vertical direction in the drawing at predetermined intervals, and a direction orthogonal to the members 21. And a plurality of bridges 22 extending therefrom are provided. Bridge 2
Reference numeral 2 is provided for cutting the upper and lower portions of the pixel.
Such a shadow mask has been manufactured by etching using a metal material. Here, the width of the member 21 is, for example, 100 μm, and is provided at 50 μm intervals.
The width of the bridge 22 is 10 μm.

In order to obtain a high-definition shadow mask, it is necessary to perform fine processing using a thin plate. However, etching using a thin plate is difficult because the etching is isotropic and the narrow bridge 22 is easily damaged. Also, when handling the processed shadow mask, there is a problem in handling since the deflection or breakage is liable to occur. If the thickness of the plate is increased or the width of the bridge 22 is increased in order to facilitate processing and handling, the vertical distance between the pixels of the organic light emitting layer is widened, and a high-definition image cannot be obtained.

[0014]

As described above, conventionally, organic light emitting layers are laminated using a lattice-shaped shadow mask, but it has been difficult to realize a high-definition image.

The present invention has been made in view of the above circumstances, and provides a mask for realizing a high-yield and high-definition organic EL display element by a simple process and a method for manufacturing an organic EL display element using the same. The purpose is to do.

[0016]

According to the present invention, there is provided a mask having an outer frame and a predetermined distance from each other inside the outer frame, the first frame extending in one direction and both ends being supported by the outer frame. And a plurality of metal pieces provided.

The method for manufacturing an organic EL display element of the present invention comprises:
Manufacture of an organic EL display element having an active matrix substrate in which a plurality of scanning lines and signal lines are arranged so as to intersect on one main surface, and a pixel electrode and a switching element are arranged for each pixel located near the intersection. A method of forming an organic layer having a light emitting ability so as to extend in one direction via a stripe-shaped mask on the active matrix substrate, and irradiating the organic layer with laser light. Cutting the organic layer so that the organic layer corresponds to each pixel.

Here, the cross section of the laser may be a band.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

As described above, in order to manufacture a high-definition organic EL display element by a conventional manufacturing method, a grid-shaped shadow mask having a very fine structure is required. However, the metal used for the shadow mask is etched. During processing, the bridge is shaved due to isotropic etching, making it difficult to produce a grid pattern shadow mask.

In the present embodiment, it is possible to manufacture a high-definition organic EL display element without using a lattice-shaped shadow mask. That is, the organic light emitting layers in the vertical direction are collectively deposited by using a stripe-shaped shadow mask described later. Then, by adding a process of cutting the organic light emitting layer by laser irradiation, occurrence of a short circuit between the pixels of the organic light emitting layer is reliably prevented.

FIG. 1 shows a vertical cross section of an active matrix type organic organic EL display device manufactured by using the mask according to the present embodiment for each process.

As shown in FIG. 1A, the first electrode 4 and the transparent electrode corresponding to each pixel are formed by repeatedly forming and patterning a film on an insulating substrate 3 having a light-transmitting property. The electrodes 5 are sequentially formed. The transparent electrode 5 may be formed by using a commonly used photoetching technique or a mask sputtering method.

Next, in order to prevent an electrical short between the pixels, the insulating layer 6 is formed in a lattice shape so as to surround the pixels by using, for example, an ultraviolet-curable acrylic resin resist.

In this embodiment, an acrylic resin is used, but other materials having photosensitivity may be used, for example, a polyimide resin may be used. After the formation of the insulating layer 6, a baking process is performed at, for example, 220 ° C. for 30 minutes to be cured.

Thereafter, as shown in FIG. 1B, organic light emitting layers 7R, 7G, 7B are formed. Organic light emitting layer 7
R, 7G, and 7B emit R, G, and B colors, respectively, and as shown in the plan view of FIG. 2, organic light emitting layers 7R, 7G for each of R, G, and B in a stripe shape. , 7B.

Here, the stripe-shaped shadow mask 1 shown in FIG. 4 is used for laminating the organic light emitting layers 7R, 7G, 7B. In the shadow mask 1, a plurality of members 2 extending in the vertical direction in the figure are supported at both ends thereof at predetermined intervals with respect to the inner wall of the outer frame 1a.
The width of the member 2 is, for example, 100 μm, and the interval is 50 μm.

In the conventional manufacturing method, a lattice-shaped shadow mask is used for laminating the organic light emitting layers as described above. However, since fine processing is difficult, a high-definition image cannot be realized.

On the other hand, in the present embodiment, the organic light emitting layers are stacked using the stripe-shaped shadow mask 1. Since there is no narrow bridge in the shadow mask 1, fine processing can be easily performed using a thin plate.

In the step of laminating the organic light emitting layers 7R, 7G, and 7B, the organic light emitting layers of any one color are stacked, the shadow mask 1 is shifted by one pixel, and the next organic light emitting layer is stacked.
Further, the next organic light emitting layer is stacked by shifting the shadow mask 1 by one column of pixels. Alternatively, the layers may be sequentially stacked using three shadow masks prepared for each of the three colors.

Thereafter, as shown in FIG. 1C, a strip-shaped excimer laser (wavelength 200 nm, power 300
mJ / cm 2, width 5 μm), and the organic light emitting layers 7R, 7G,
Irradiation at a pixel pitch is performed while scanning in a direction orthogonal to the stripe direction of the organic light emitting layers 7R, 7G, and 7B.
Is cut to correspond to each pixel. As a result, occurrence of a short circuit between the pixels of the organic light emitting layers 7R, 7G, 7B can be reliably prevented. Here, since the organic light emitting layers 7R, 7G, and 7B are irradiated with laser so as to surely cut them between the pixels, the surface of the irradiated insulating layer 6 has depressions 6a, but has no influence on the characteristics of the device. Do not give. FIG. 3 shows that the organic light emitting layers 7R and 7R are irradiated by laser irradiation.
The plane state after cutting G and 7B with an interval 12 is shown.

As shown in FIG. 1D, an electrode material such as Al is deposited to cover the entire surface, and the second electrode 8 is formed in a solid shape. Here, all processes after the formation of the insulating layer 6 are performed under vacuum conditions.

In order to seal the surface to the array substrate obtained in this manner, a portion corresponding to the outside of the pixel region where the organic light emitting layers 7R, 7G and 7B of the array substrate are laminated is placed on the opposite cover glass (not shown). UV-curable sealing material is applied to the position to be cured. Then, the opposing cover glass and the array substrate are laminated. Thereafter, the sealing material is cured by irradiating ultraviolet rays to complete the sealing material. Here, the sticking step of the seal is performed in an atmosphere of N2 or Ar gas.

The active matrix organic EL display device of the color display type manufactured according to the present embodiment is obtained by laminating organic light emitting layers using a stripe-shaped shadow mask which can be easily finely processed, and cutting by irradiating a laser beam. , High-definition display quality can be realized.

The above-described embodiment is an example, and does not limit the present invention. For example, the material, the lamination method, and the like used for forming the film in the above embodiment can be freely changed as necessary.

[0036]

As described above, according to the present invention,
The organic light-emitting layer is laminated using a stripe-shaped shadow mask that is easy to finely process, and then irradiated with a laser beam to be cut for each pixel.
The manufacture of the L display device can be realized by a simple process.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an element showing a method of manufacturing an organic EL display element according to an embodiment of the present invention for each process.

FIG. 2 is a plan view showing a state in which an organic light emitting layer is stacked, which is one step in the manufacturing method.

FIG. 3 is a plan view showing a state in which the organic light emitting layer after lamination shown in FIG. 3 is cut by performing laser irradiation.

FIG. 4 is a plan view showing a configuration of a stripe-shaped shadow mask used in the manufacturing method.

FIG. 5 is a plan view showing a mask used for laminating an organic light emitting layer in a conventional manufacturing method.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 shadow mask 1a outer frame 2 member 3 insulating substrate 4 first electrode 5 transparent electrode 6 insulating layer 7R, 7G, 7B organic light emitting layer 8 second electrode

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05B 33/12 H05B 33/12 B 33/14 33/14 A F term (Reference) 3K007 AB04 AB18 BA06 CB01 DA01 DB03 EB00 FA01 4K029 BA62 BB03 BC07 BD00 CA01 GA00 HA03 5C094 AA05 AA43 BA03 BA12 BA27 CA19 CA24 DA13 DB04 EA04 EA05 EB02 ED15 FA01 FA02 FB01 FB12 FB14 FB15 GB10

Claims (3)

[Claims] An outer frame, and a plurality of metal pieces provided in the inner side of the outer frame at predetermined intervals from each other while extending in one direction and both ends are supported by the outer frame. A mask comprising: 2. An organic circuit comprising: an active matrix substrate in which a plurality of scanning lines and signal lines are arranged on one main surface so as to intersect, and for each pixel located near an intersection, a pixel electrode and a switching element are arranged. In the method for manufacturing an EL display element, a step of forming an organic layer having a luminous ability so as to extend in one direction through a stripe-shaped mask on the active matrix substrate; Irradiating and cutting to make the organic layer correspond to each pixel. A method for manufacturing an organic EL display element, comprising: 3. The method for manufacturing an organic EL display element according to claim 2, wherein said laser has a band-shaped cross section.