KR20090046639A - Attaching device and manufacturing method for organic light emitting display using the same - Google Patents

Abstract

The present invention provides a substrate stage comprising cooling means and heating means; A mask facing the substrate stage and including an open area and a blocking area; And it provides a bonding apparatus comprising a laser irradiation device and a method of manufacturing an organic light emitting display device using the same.

Fastening device

Description

Attaching device and manufacturing method for organic light emitting display using same

The present invention relates to a bonding apparatus and a method of manufacturing an organic light emitting display device using the same.

Recently, a flat display device such as a liquid crystal display, an organic light emitting display, or a plasma display panel that solves the shortcomings of a conventional display device such as a cathode ray tube. (flat panel display) is drawing attention.

Since the liquid crystal display is not a self-light emitting device, there are limitations in brightness, contrast, viewing angle, and large area, and although the PDP is a self-light emitting device, it is heavier in weight and consumes more power than other flat panel displays, and is manufactured. The problem is that the method is complex.

On the other hand, the organic light emitting display device is excellent in viewing angle, contrast, etc., because it is a self-luminous element, and can be light and thin because it does not require a backlight, and is advantageous in terms of power consumption. In addition, since it is possible to drive a DC low voltage, fast response speed, and all solid, it is resistant to external shock, wide use temperature range, and has a simple and inexpensive manufacturing method.

In the organic light emitting display device as described above, an organic light emitting diode array substrate on which a plurality of organic light emitting diodes are formed and an encapsulation substrate for encapsulating the organic light emitting diode are bonded, and then scribed for each organic light emitting diode to perform a module operation. And an organic light emitting display device.

Recently, when the organic light emitting diode array substrate and the encapsulation substrate are bonded, a frit is used as an encapsulant. The frit is the same glass material and inorganic material as the base substrate of the organic light emitting diode array substrate, and therefore, moisture Penetration into the organic light emitting display device can be effectively prevented.

A method of bonding the organic light emitting display device to the frit will be described below.

First, a frit is applied onto an organic light emitting element array substrate or an encapsulation substrate. When applied to the organic light emitting diode array substrate, the frit may be formed inside the scribing line to be separated into each organic light emitting display device, and when applied to the encapsulation substrate, the frit may be applied on the corresponding area. . Then, the sealant is applied to the outer line of the organic light emitting diode array substrate or the encapsulation substrate to bond the organic light emitting element array substrate and the encapsulation substrate.

Next, the two bonded substrates are placed in an oven and a first firing process is performed to blow out the organic components of the frit. Then, the mask is aligned on the two substrates on which the primary firing is completed, the laser is irradiated onto the fired frit to complete the secondary firing, and then scribed and separated into the organic light emitting display devices.

The bonding process has a disadvantage in that the process time is long because the second firing is performed again by laser after the first firing in the oven. In addition, since the entire substrate is put into the oven, it is impossible to apply a sufficient temperature for firing the frit to prevent damage to the organic layers of the organic light emitting element. Therefore, the organic components included in the frit are not sufficiently removed in the primary firing, and the efficiency of the secondary firing is lowered.

In addition, during the second firing, since the laser is locally irradiated to the two bonded substrates, the substrate is locally heated to a high temperature. Therefore, there is a problem that a crack occurs in the substrate due to the temperature difference between the portion irradiated with the laser and the other substrate.

Accordingly, an object of the present invention is to provide a method of manufacturing an organic light emitting display device which can reduce the processing time, prevent damage to the substrate and the organic light emitting device, and improve the sealing effect.

In order to achieve the above object, the present invention, the substrate stage with cooling means and heating means; A mask facing the substrate stage and including an open area and a blocking area; And a bonding apparatus including a laser irradiation apparatus.

In addition, the present invention comprises the steps of providing an organic light emitting device array substrate comprising a plurality of organic light emitting devices; Providing an encapsulation substrate for encapsulating the organic light emitting device array substrate; Coating a frit on an encapsulation substrate corresponding to outer regions of the plurality of organic light emitting diodes; Aligning the organic light emitting device array substrate and the encapsulation substrate; Loading the two aligned substrates onto a substrate stage comprising cooling means and heating means; Melting the frit by irradiating a laser onto the frit while operating the heating means of the substrate stage; And secondly bonding the organic light emitting element array substrate to the encapsulation substrate by curing the frit while alternately operating the heating means and the cooling means of the substrate stage, thereby providing a method of manufacturing an organic light emitting display device. .

The present invention can shorten the process time when manufacturing the organic light emitting display device, prevent damage to the substrate and the organic light emitting device, and improve the encapsulation effect, thereby manufacturing cost, manufacturing yield and product reliability. There is an effect to improve.

Details of the above object and technical configuration and the effects thereof according to the present invention will be more clearly understood by the following detailed description with reference to the drawings showing an embodiment of the present invention. In addition, in the drawings, the length, thickness, etc. of layers and regions may be exaggerated for convenience. Like numbers refer to like elements throughout.

1 is a plan view illustrating an organic light emitting diode array substrate according to an exemplary embodiment of the present invention.

Referring to FIG. 1, an organic light emitting diode array substrate is manufactured by forming a plurality of organic light emitting diodes 101 including a thin film transistor and an organic light emitting diode on a substrate 100. In this case, the substrate 100 may include glass, plastic, or metal, and may be a substrate having flexible properties.

Here, referring to FIG. 2, when the structure of the organic light emitting diode according to the exemplary embodiment of the present invention is described, the buffer layer 105 is positioned on the substrate 100, and the thin film transistor TFT is disposed on the buffer layer 105. Is located.

The thin film transistor TFT may include a semiconductor layer 110, a first insulating layer 120 as a gate insulating layer, a gate electrode 130, a second insulating layer 140 as an interlayer insulating layer, a source electrode, and a drain electrode ( 150a, 150b).

The third insulating layer 160, which is an interlayer insulating layer, is disposed on the thin film transistor TFT. The third insulating layer 160 may be a planarization insulating layer, and a contact hole 165 exposing a part of the drain electrode 150b is disposed in the third insulating layer 160.

The first electrode 170 is electrically connected to the drain electrode 150b through the contact hole 165 on the third insulating layer 160. The first electrode 170 may be an anode and may include a transparent conductive oxide film such as ITO.

The bank layer 180 including an opening 185 exposing a part of the first electrode 170 and defining a light emitting area is positioned on the first electrode 170.

The organic light emitting layer 190 is positioned on the first electrode 170 exposed by the bank layer 180, and the second electrode 195 is positioned on the organic light emitting layer 190. The second electrode 195 may be a cathode or a common electrode. The second electrode 195 may include aluminum, magnesium, silver, or the like having a low work function and excellent reflectivity, and may be formed as a semi-transmissive electrode.

The organic light emitting layer 190 receives holes from the first electrode 170 and generates electrons by receiving electrons from the second electrode 190. Then, the video image is displayed by the light emitted by the excitons returning to the ground state. Although not shown, a hole / electron injection and transport layer is provided between the organic light emitting layer 190 and the first electrode 170 and between the organic light emitting layer 190 and the second electrode 195 to help transport holes and electrons. Can be located.

Referring to FIG. 3, an encapsulation substrate 200 for encapsulating an organic light emitting diode array substrate is prepared, and a frit 210 is coated on the encapsulation substrate 200. Here, the frit 210 may include any one or more selected from the group consisting of lead oxide (PbO), diboron trioxide (B 2 O 3), and silicon dioxide (SiO 2). The frit 210 may be applied to the inside of the scribing line of the encapsulation substrate 100 so as to surround each organic light emitting device.

In addition, the sealant 220 may be coated on the encapsulation substrate 200. The sealant 220 may include an organic material such as an epoxy resin. The sealant 220 is for temporarily bonding the organic light emitting element array and the encapsulation substrate, and may be applied on the encapsulation substrate 200 to surround the outer line of the encapsulation substrate 200 or the plurality of organic light emitting elements. have.

Here, the application of the frit 210 and the sealant 220 may use a screen printing or dispensing method.

Referring to FIG. 4, the organic light emitting diode array substrate 100, the frit 210, and the encapsulation substrate 200 coated with the sealant 220 are aligned, and the two substrates are temporarily temporary using the sealant 220. Stick together. Thereafter, the sealant 220 is cured by irradiating ultraviolet rays using a mask 250 having an open area in an area corresponding to the area where the sealant 220 is applied.

Referring to FIG. 5, the bonded substrates 100 and 200 are positioned on the substrate stage 300 of the bonding apparatus. The bonding apparatus includes a substrate stage 300 for supporting a substrate, a mask 350 having an open area and a solid area, and a laser irradiation device (not shown).

Here, as illustrated in FIG. 6, the substrate stage 300 may include a cooling unit 310 and a heating unit 320 on one surface of or in the interior of the substrate stage 300. The cooling means 310 may use a water-cooled or air-cooled method, and the heating means 320 may be a resistive heating method. The configurations of the cooling means 310 and the heating means 320 are not limited to those shown in FIG. 7, and any configuration may be used as long as the entire substrate can be uniformly cooled / heated.

In addition, although not shown, the substrate stage 300 may include substrate fixing means (not shown) for seating the substrate. The bonding apparatus may further include a transfer means for transferring the substrate and a mask alignment means for aligning the mask with the substrate.

Next, the mask 350 is aligned with the two bonded substrates 100 and 200. Here, the pattern of the open area of the mask 350 may correspond to the pattern of the frit 210. The frit 210 is first fired by first irradiating a laser beam through the open area of the mask 350 on the frit 210. At this time, the organic component in the frit 210 is removed. Here, since the first firing is a step of removing the organic components in the frit 210, a high power laser is not required.

In the first firing, when the heating means of the substrate stage 300 is operated to heat the entire substrate to a predetermined temperature, heat may be applied to the frit 210 from the bottom of the substrate. Firing can be carried out more efficiently.

Conventionally, since the oven was used during the primary firing of the frit, in order to prevent the organic layers of the organic light emitting element from being damaged, the temperature of the oven could not be increased above a certain temperature. Therefore, the firing of the frit is not sufficiently made, there is a problem that the encapsulation efficiency is lowered, and the process time is long because the primary firing of the frit and the secondary firing to be performed are separated into different processes. there was.

In the present invention, by firing the frit using a laser, higher energy can be supplied to the frit, and the frit can be effectively fired without damaging the organic layer of the organic light emitting element, and the secondary firing of the frit is followed by a secondary Since it is carried out at the same stage as the firing, the process time can be reduced.

Referring to FIG. 7, the frit 210 is melted by irradiating a second laser to the frit 210 while operating the heating means of the substrate stage 300. In this case, the power of the laser may be 10 to 20W, and a method of irradiating the laser once or twice or more may be used.

Here, in order to melt the frit 210, a laser having a very high energy is irradiated to a part of the substrate on which the frit is formed. In this case, since the substrate is locally heated, the temperature difference with the surroundings is extremely high and cracks may occur on the substrate. Can be. Therefore, at this time, when the heating means of the substrate stage 300 is operated to heat the substrate to a constant temperature, the temperature of the entire substrate becomes high. Therefore, since the temperature difference between the portion to which the laser is irradiated and the other portion is reduced, it is possible to reduce the occurrence of cracks in the substrate.

In addition, when the heating means of the substrate stage 300 is operated during the secondary firing, and the entire substrate is heated to a predetermined temperature, heat may be applied to the frit 210 from the lower part of the substrate. Firing can be carried out more efficiently.

Next, the cooling means and the heating means are operated to harden the frit 210 while lowering the temperature of the substrate so that both substrates 100 and 200 are completely bonded to the secondary. Here, if the temperature of the bonded substrates 100 and 200 drops sharply, there is a risk of cracking on the substrate. Therefore, even after the curing process is completed, the heating means and the cooling means of the substrate stage 300 are alternately operated, so that the temperature of the substrate is gradually decreased.

Then, although not shown, scribing the bonded substrate is completed, and a module operation is performed to manufacture each organic light emitting display device.

In an embodiment of the present invention, the frit and the sealant are applied to the encapsulation substrate, but are not limited thereto, and the frit and the sealant may be applied to the organic light emitting device array substrate.

Although the present invention has been illustrated and described with reference to one embodiment as described above, the present invention is not limited to the above-described embodiments and is provided to those skilled in the art without departing from the spirit of the invention. Various changes and modifications will be possible.

1 is a plan view illustrating an organic light emitting diode array substrate according to an exemplary embodiment of the present invention.

2 is a cross-sectional view illustrating a structure of an organic light emitting diode according to an embodiment of the present invention.

3 to 5 and 7 are cross-sectional views of processes for describing a method of manufacturing an organic light emitting display device according to an embodiment of the present invention.

6 is a plan view showing a substrate stage of the bonding apparatus according to an embodiment of the present invention.

Claims (9)

A substrate stage equipped with cooling means and heating means; A mask facing the substrate stage and including an open area and a blocking area; And A bonding device comprising a laser irradiation device. The method of claim 1, A bonding apparatus further comprising a substrate moving means. The method of claim 1, And a mask aligning means for aligning the mask with a substrate. Providing an organic light emitting device array substrate comprising a plurality of organic light emitting devices; Providing an encapsulation substrate for encapsulating the organic light emitting device array substrate; Coating a frit on an encapsulation substrate corresponding to outer regions of the plurality of organic light emitting diodes; Aligning the organic light emitting device array substrate and the encapsulation substrate; Loading the aligned substrates onto a substrate stage comprising cooling means and heating means; Melting the frit by irradiating a laser onto the frit while operating the heating means of the substrate stage; And And curing the frit to bond the organic light emitting element array substrate to the encapsulation substrate while alternately operating the cooling means and the heating means of the substrate stage. The method of claim 4, wherein After applying the frit to the encapsulation substrate, irradiating a laser onto the frit to remove organic substances in the frit. The method according to claim 4 or 5, And aligning a mask having an open area in a region corresponding to the frit, before irradiating a laser onto the frit. The method according to claim 4 or 5, And after applying the frit to the encapsulation substrate, applying a sealant to a predetermined region including an outer region of the encapsulation substrate. The method of claim 7, wherein And aligning the sealant substrate with the encapsulation substrate, followed by ultraviolet curing of the sealant. The method of claim 4, wherein The frit is any one or more selected from the group consisting of lead oxide (PbO), diboron trioxide (B2O3) and silicon dioxide (SiO2).

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