KR101630318B1 - Organic Light Emitting Display Device and Method for fabricating the same - Google Patents

Abstract

[0001] The present invention relates to an organic light emitting display and a method of manufacturing the same, and more particularly, to an organic light emitting display and a method of manufacturing the same, including a first substrate on which at least one sub-pixel driver array including thin film transistors is formed, A sealing member having a filler injection port formed on an outer periphery of the first substrate and the second substrate and having a filler injection port on one side thereof, And a filler made of a photocurable liquid polymer precursor is disposed between the second substrate.

Sealing, filling, polymer, DOD, organic electroluminescence

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting display device,

The present invention relates to an organic light emitting display and a method of manufacturing the same, and more particularly, to an organic light emitting display capable of preventing transmittance reduction and life span of an organic light emitting display and a method of manufacturing the same.

The image display device that realizes various information on the screen is a core technology of the information communication age and it is becoming thinner, lighter, more portable and higher performance. An organic light emitting display device for displaying an image by controlling the amount of light emitted from the organic light emitting layer by using a flat panel display capable of reducing weight and volume, which is a disadvantage of a cathode ray tube (CRT), has attracted attention. Organic electroluminescent display devices are self-luminous elements using a thin light emitting layer between electrodes and have the advantage of thinning like paper.

In an active matrix organic electroluminescence (AM organic electroluminescence) display device, pixels composed of three color (R, G, B) sub-pixels are arranged in a matrix form to display an image. Each sub-pixel includes an organic electroluminescent (OEL) cell and a cell driver for independently driving the OEL cell. The cell driver includes at least two thin film transistors and a storage capacitor and controls the amount of current supplied to the organic light emitting display according to the data signal to control the brightness of the organic light emitting display.

A conventional AM organic electroluminescent display device emits light through a substrate in an encapsulation structure in which a packaging plate is attached to a substrate on which a sub-pixel driver array and an organic electroluminescent array are formed. However, in the conventional AM organic electroluminescent display device, when the process of the sub-pixel driving part is completed and the process of the organic electroluminescent array is defective, the entire substrate must be defective and the whole process yield is low. Further, the packaging plate has a problem that the aperture ratio is limited and it is difficult to apply to a high-resolution display device.

In order to solve these problems, a dual plate type AM organic electroluminescent display device has recently been proposed in which a sub-pixel driver array and an organic electroluminescent array are separately formed on different substrates and vacuum-bonded. However, in the dual plate type AM organic light emitting display, the pressure inside the panel increases when vacuum is attached, or moisture permeates from the outside. The moisture penetration into the panel is accelerated due to the difference between the vacuum and the external pressure in the panel or the lifetime of the device is deteriorated. In order to solve this problem, a filler is injected into the AM organic electroluminescence display device to absorb moisture or gas, but the light emitting property and transmittance are lowered by the filler.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide an organic light emitting display device and a method of manufacturing the same, which can prevent deterioration of transmittance and prolong life of the organic light emitting display device.

The organic electroluminescent display device according to the present invention includes a first substrate on which at least one sub-pixel driver array formed of thin film transistors is formed, a second substrate arranged to face the first substrate and having at least one organic electroluminescent array formed thereon, A sealing material formed along the periphery of the first substrate and the second substrate and having a filling material injection port on one side and a sealing material disposed between the first substrate and the second substrate in a film diagram on the inside of the sealing material and the filling material injection port, And a filler made of a fused liquid polymer precursor.

Here, the filler is characterized by being made of a photo-curable liquid polymer precursor represented by the following formulas (1) to (4).

Formula 1

(2)

(3)

Formula 4

Here, the GMA of the filler is 5 wt% to 10 wt%, the PHEA is 40 wt% to 50 wt%, the DPMA is 35 wt% to 45 wt%, and the PETIA is 1 wt% to 5 wt% .

The filler is characterized by adding 1 wt% to 3 wt% of Irgacure 369 used as a photoinitiator.

In addition, the filler is formed over the entire space except the sub-pixel driver array and the organic electroluminescent array between the first substrate and the second substrate.

A method of manufacturing an organic light emitting display according to the present invention includes the steps of preparing a first substrate having at least one sub-pixel driver array formed of thin film transistors and a second substrate having at least one organic electroluminescent array formed thereon, A method of manufacturing a semiconductor device, comprising the steps of: applying a sealing material along an outer periphery of a substrate; bonding the first substrate and the second substrate; cutting the first substrate and the second substrate to form a filler injection port; Injecting a filler made of a photocurable liquid polymer precursor between the first substrate and the second substrate, and UV curing the sealant and the filler.

Wherein the step of injecting the filler comprises the steps of injecting the filler while maintaining the vacuum between the first substrate and the second substrate inside the sealant through the filler injection port and injecting the filler through the filler injection hole, And a step of closing the valve.

Here, the step of injecting the filler and the step of UV curing are performed in an N ₂ atmosphere.

The organic light emitting display device according to the present invention can prevent the transmittance of the organic light emitting display device from being lowered by using a filler having a high transmittance.

The organic light emitting display according to the present invention may absorb moisture or gas generated from the outside or from the inside to prevent deterioration of the organic layer, thereby prolonging the lifetime of the organic light emitting display.

In addition, the organic light emitting display device according to the present invention can improve the durability and reliability of the organic light emitting display device because the filler is injected so as to fill the entire area to absorb external impact.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a plan view schematically illustrating an organic light emitting display according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view schematically illustrating an organic light emitting display device taken along the line I-I 'of FIG.

1 and 2, the organic light emitting display 100 includes a first substrate 110 having at least one sub-pixel driver array formed in units of sub-pixels, a second substrate 130 having an organic electroluminescent array, A sealant 150 for bonding the first substrate 110 and the second substrate 130 together and a filler 156 injected between the first substrate 110 and the second substrate 130 inside the sealant do.

Here, the sub-pixel driver array includes sub-pixel drivers of a plurality of sub-pixels constituting an image display unit, and the organic electroluminescent array includes organic electroluminescence of a plurality of sub-pixels.

The first substrate 110 includes a gate electrode, a gate insulating film covering the gate electrode, an active layer overlapping the gate electrode with the gate insulating film interposed therebetween to form a channel, a drain electrode and a source electrode opposing each other with the channel therebetween, And a protective film formed to expose the drain electrode.

Here, the gate electrode, the source / drain electrode, the active layer, the gate insulating film, and the passivation film form a thin film transistor (TFT) 112 and constitute a sub-pixel driver array. The active layer may be formed of a semiconductor layer and an ohmic contact layer.

The second substrate 130 includes a first electrode 132, an organic layer 134 including a light emitting layer formed on the first electrode 132, a second electrode 136 formed on the organic layer 134, And a spacer 138 formed between the organic layer 122 and the organic layer 134 to maintain a cell gap.

Here, the first electrode 132, the organic layer 134, the second electrode 136, and the spacer 138 constitute an organic electroluminescent array. The spacers 138 maintain the cell gap between the first substrate 110 and the second substrate 130 and the second electrodes 136 above the spacers 138 are electrically connected to the film transistors of the first substrate 110 As shown in FIG.

The sealing material 150 is for bonding and sealing the substrates, and is formed at the edges along the peripheries of the first substrate 110 and the second substrate 130 on the image non-display portion to prevent moisture from penetrating from the outside. The sealing material 150 is formed in a shape having a filler injection port 158 on one side of one end of the substrate 110/130.

The filler 156 is for absorbing moisture and gas components such as moisture and oxygen which are infiltrated from the outside or generated inside. The filler 156 is filled in the space between the first substrate 110 and the second substrate 130 inside the sealing material 150 Respectively. The filler 156 is formed in a space excluding the sub-pixel driver array and the organic electroluminescent array, and protects the arrays from external impact, thereby improving durability and reliability of the organic electro-luminescent display.

As the filler 156, a UV curable liquid pre-polymer is used. Specifically, the filler 156 is composed of polymers having the following formulas (1) to (4).

Here, GMA (Glycidyl methacrylate) is composed of 5 wt% to 10 wt% based on the total weight.

Here, PHEA (phenolethyleneoxideacrylate) is composed of 40 wt% to 50 wt% of the total weight.

Here, DPMC (Dicyclopentanyl methacrylate) is composed of 35 wt% to 45 wt% of the total weight.

 Here, PETIA (Pentaerythritol triacrylate) is composed of 1 wt% to 5 wt% based on the total weight.

It is preferable that the filler 156 contains Irgacure 369 as a photoinitiator and Irgacure 369 as 1 wt% to 3 wt% of the total weight.

Referring to FIG. 3, when the filler 156 made of the photocurable liquid polymer precursor according to the present invention is used, the transmittance is 96% or more regardless of the number of hard baking after photocuring at a BLUE wavelength (400 nm) . Details will be described with reference to the following table.

standard
(BLUE 400nm transmittance: 52.2605%) 1 time
(UV) Episode 2
(220 DEG C / 30 min) 3rd time
(220 DEG C / 60min) 4 times
(220 DEG C / 90 min) Transmittance (%)  50.9458 52.236 51.6911 51.9797 Transmittance relative to baseline 97.5% 100.0% 98.9% 99.5%

As shown in Table 1, when the filler according to the present invention was not applied, the transmittance at a BLUE wavelength (400 nm) was 52.2605%. As a result, the transmittance of the filler 156 according to the present invention was measured once to four times after the injection of the filler 156 according to the present invention. More specifically, the filler 156 according to the present invention was injected and UV-cured in one experiment, and the transmittance was 50.9458%. That is, it can be seen that the transmittance of the reference is 97.5%. In the second experiment, the filler 156 according to the present invention was injected and the transmittance after heat resistance test at 220 캜 for 30 minutes was 52.236%. That is, it can be seen that the transmittance with respect to the reference is about 100.0%. The permeability after injecting the filler 156 according to the present invention at the time of the third experiment and after the heat resistance test at 220 캜 for 60 minutes was 51.6911%. That is, it can be seen that the transmittance relative to the reference is about 98.9%. The transmittance after heat resistance test at 220 캜 for 90 minutes in the fourth experiment was 52.236%. That is, it can be seen that the transmittance with respect to the reference is about 99.5%. As described above, even when the filler 156 according to the present invention is injected into the entire space between the substrates 110 and 130, the transmittance of the organic light emitting display device can be prevented from being lowered because the transmittance is higher than 97%. In all other experiments, it was found that the transmittance of the reference was 96% or more.

Referring to FIG. 4, when the filler 156 according to the present invention was irradiated with UV for 3 minutes or more at UV intensity of 2 mW / cm 2 or more, the degree of curing was 95% or more.

As described above, the filler 156 made of the photocurable liquid polymer precursor according to the present invention has a high transmittance as well as a high degree of curing, so that the filler 156 is evenly filled in the substrate 110/130 within a short time. The filler 156 according to the present invention effectively absorbs gas components, moisture, or moisture permeating from the outside in a shorter time in the organic electroluminescence display device. As a result, deterioration of elements inside the organic light emitting display can be prevented, and thus the lifetime and reliability of the organic light emitting display can be improved.

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

5, a first substrate 110 on which a thin film transistor 112 is formed, which constitutes a sub-pixel driver array including electrodes and insulating film patterns, a first substrate 110 on which electrodes 132 and 136 and organic layers 134 patterns A second substrate 130 on which an organic electroluminescent array is formed. At this time, the sealing material 150 is coated on the first substrate 110 along the outer circumference. The first substrate 110 and the second substrate 130 are loaded into the vacuum chamber so that the first substrate 110 and the second substrate 130 are bonded together by the sealing material 150.

Referring to FIGS. 6 and 7, the first substrate 110 and the second substrate 130 are injected through the filler injection port 158 opened by the scribe line 170. At this time, the inside of the vacuum chamber is pressurized to inject the filler 156 while maintaining the vacuum state. The filler 156 is injected as it is sucked between the first substrate 110 and the second substrate 130 by a capillary phenomenon in a vacuum state in a vacuum chamber so that the filler 156 is completely filled with no gap between the substrates 110/130 . The sub-pixel driver array and the filler 156 formed on the entire surface of the organic electroluminescent array protect the arrays from external impacts, thereby improving durability and reliability of the organic electro-luminescent display device.

As the filler 156, a UV curable liquid pre-polymer is used. Specifically, the filler 156 is made of polymers having the following formulas (1) to (4).

Formula 1

(2)

(3)

Formula 4

Here, the GMA is 5 wt% to 10 wt%, the PHEA is 40 wt% to 50 wt%, the DPMA is 35 wt% to 45 wt%, and the PETIA is 1 wt% to 5 wt%.

The filler 156 preferably contains Irgacure 369 as a photoinitiator and Irgacure 369 as a photoinitiator in an amount of 1 wt% to 3 wt% based on the total weight of the filler.

When the filler 156 made of the photocurable liquid polymer precursor according to the present invention is used, the transmittance of the display device can be prevented from being lowered because the transmittance of the filler 156 is greater than 96% at the BLUE wavelength (400 nm).

The filler 156 implantation process is performed in an N ₂ atmosphere because the UV curing process to be performed at a later time can be performed in an N ₂ atmosphere to improve the curing efficiency. At this time, since the inside of the vacuum chamber need not be formed in a separate N ₂ atmosphere after injecting the filler 156, the process time can be shortened.

Next, a UV curing process is performed to harden the sealing material 150 and the filler 156 simultaneously. The filler is uniformly distributed throughout the first substrate 110 and the second substrate 130 by the UV curing process and simultaneously the first substrate 110 and the second substrate 130 are completely sealed. At this time, since the filler injection port 158 is automatically closed by the hardening of the filler 156, there is no possibility that moisture or the like will be infiltrated from the outside through the filler injection port 158, and a separate process for closing the filler injection port 158 is performed There is no need to do this. The filler 156 absorbs moisture and gas components such as oxygen generated in the first substrate 110 and the second substrate 130 and prevents moisture and the like from penetrating from the outside, . That is, by using the filler 156 according to the present invention, the life of the organic light emitting display device can be extended and reliability can be improved.

The above-described techniques represent presently preferred embodiments, and the present invention is not limited to the above-described embodiments and the accompanying drawings. Modifications and other uses of the embodiments will be apparent to those skilled in the art, and such modifications and other uses are intended to be included within the spirit of the present invention or defined by the scope of the appended claims.

1 is a plan view showing an organic light emitting display according to an embodiment of the present invention.

2 is a cross-sectional view schematically showing an organic light emitting display device taken along the line I-I 'in FIG.

3 is a graph showing transmittance of an organic light emitting display according to an embodiment of the present invention.

4 is a graph showing the degree of curing of the filler according to the UV intensity according to an embodiment of the present invention.

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

Description of the Related Art

110: first substrate 112: thin film transistor

130: second substrate 132: first electrode

134: organic layer 136: second electrode

138: spacer 150: sealing material

156: Filler 158: Filler inlet

Claims (10)

A first substrate on which at least one sub-pixel driver array composed of thin film transistors is formed; A second substrate disposed to face the first substrate and having at least one organic electroluminescent array formed thereon; A sealing material located along the outer periphery of the first substrate and the second substrate and having a filler injection port on one side; And And a filler made of a photocurable liquid polymer precursor between the first substrate and the second substrate so as to cover the sealing material and the filler injection port, Wherein the filler is made of a photocurable liquid polymer precursor represented by the following formulas (1) to (4) Formula 1

(2)

(3)

Formula 4

Wherein the GMA of the filler is 5 wt% to 10 wt%, the PHEA is 40 wt% to 50 wt%, the DPMA is 35 wt% to 45 wt%, and the PETIA is 1 wt% to 5 wt% . delete delete The organic electroluminescent display device according to claim 1, wherein the filler is a photoinitiator and contains 1 wt% to 3 wt% of the filler. The organic light emitting display as claimed in claim 1, wherein the filler is formed in a space entirely between the first substrate and the second substrate, excluding the sub-pixel driver array and the organic electroluminescent array. Preparing a first substrate having at least one sub-pixel driver array formed of thin film transistors and a second substrate having at least one organic electroluminescent array formed thereon; Applying a sealant along an outer periphery of the first substrate; Attaching the first substrate and the second substrate together; Forming a filling agent inlet by cutting the first substrate and the second substrate; Injecting a filler made of a photocurable liquid polymer precursor between the first substrate and the second substrate; And And UV-curing the sealant and the filler, Wherein the filler is a photocurable liquid polymer precursor represented by the following formulas (1) to (4) Formula 1

(2)

(3)

Formula 4

Wherein the GMA is 5 wt% to 10 wt%, the PHEA is 40 wt% to 50 wt%, the DPMA is 35 wt% to 45 wt%, the PETIA is 1 wt% to 5 wt%, the filler is a photoinitiator, To 3 wt% based on the total weight of the organic EL device. delete delete 7. The method of claim 6, wherein injecting the filler comprises: Injecting the filler while maintaining the vacuum between the first substrate and the second substrate on the inside of the sealing material through the filler inlet; And And the filler injection port is closed by the filler due to the vacuum state. The method according to claim 6, wherein the step of injecting the filler and the step of UV curing are performed in an N ₂ atmosphere.

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