KR100623704B1 - method for fabricating Organic light emission device panel - Google Patents

Abstract

The present invention relates to a method of manufacturing an organic light emitting display device, by using an UV curable polymer in an organic film layer except for a light emitting layer, an organic film existing in an encapsulation can be easily removed to enhance the adhesive strength of a sealant, thereby forming an organic light emitting device therein. Provided are a method of manufacturing an organic light emitting display device that can be protected.

In addition, in the method of manufacturing an organic light emitting display device, an organic electric field capable of stably forming an organic light emitting layer pattern by a laser thermal transfer method by providing a flattening function to alleviate irregularities of a substrate by using a polymer as the organic film layer. A method of manufacturing a light emitting display device is provided.

Organic light emitting display, encapsulation, UV curable polymer

Description

Method for fabricating organic light emission device panel

1A and 1B are cross-sectional views illustrating a method of manufacturing an organic light emitting display device by a conventional laser thermal transfer method.

2A through 2E are diagrams for describing a method of manufacturing an organic light emitting display device according to an exemplary embodiment of the present invention.

Description of reference numerals for the main parts of the drawings

10: insulating substrate 11: first electrode

12: first organic film 20: donor substrate

23 ': organic light emitting layer 24: second electrode

30: substrate 40: sealing material

The present invention relates to a method of manufacturing an organic light emitting display device, and more particularly, to a method of manufacturing an organic light emitting display device for removing an organic film present in an encapsulation portion of an organic light emitting display device.

Among the flat panel display devices, the organic light emitting display device has a high response time with a response speed of 1 ms or less, low power consumption, and no self-emission, so there is no problem in viewing angle. . In addition, low-temperature manufacturing is possible, and the manufacturing process is simple based on the existing semiconductor process technology has attracted attention as a next-generation flat panel display device in the future.

At least an organic layer including a light emitting layer is present in a unit pixel of the organic light emitting display device. The full color can be realized by patterning a light emitting layer having three primary colors of R, G, and B in the organic light emitting display device.

The organic layer may be formed using a vacuum deposition method or a conventional optical etching method using a shadow mask, but in the case of vacuum deposition method, it is difficult to form an organic layer in a fine pattern, and thus it is difficult to realize a full-color display. In this case, there is a problem in that light emission characteristics such as lifetime and efficiency are deteriorated due to damage to the organic layer by the developer or etching solution.

Accordingly, a method of patterning an organic layer using laser induced thermal imaging (LITI) has been introduced as a method to solve this problem.

The laser thermal transfer method is a method in which light is emitted from a light source and absorbed by a light-to-heat conversion layer of a donor substrate to convert light into thermal energy, and the organic material formed on the transfer layer is transferred to the substrate by the converted thermal energy.

The pattern formation method of the organic light emitting display device by the laser thermal transfer method is disclosed in Korean Patent Registration No. 10-0342653, and has already been disclosed in US Patent Nos. 5,998,085, 6,214,520 and 6,114,085.

1A and 1B are cross-sectional views illustrating a method of manufacturing an organic light emitting display device by a conventional laser thermal transfer method.

Referring to FIG. 1A, first, a semiconductor layer 125, a gate insulating layer 120, a gate electrode 135, an interlayer insulating layer 130, and a source / layer may be formed on a buffer layer 110 of an insulating substrate 100 in a conventional manner. A thin film transistor having a drain electrode 145 is formed.

A passivation film 140 is formed over the entire surface of the interlayer insulating film 130, and a planarization film 150 is formed on the passivation film 140, and then one of the source / drain electrodes 145 is formed. A via hole 165 is formed to expose a predetermined portion of the.

The pixel electrode 160 is formed to contact the exposed predetermined portion of the source / drain electrode 145 through the via hole 165.

In this case, after forming the pixel defining layer 170 covering the pixel electrode 160 having the curved shape of the via hole 160, a portion of the pixel electrode 160 is formed on the pixel defining layer 170. An opening 195 is formed to expose the opening.

Thus, a substrate having a thin film transistor and having the pixel electrode formed thereon is manufactured.

Meanwhile, the donor substrate 200 for laser transfer is manufactured by sequentially stacking the base layer 201, the light-to-heat conversion layer 202, and the transfer layer 203.

Subsequently, after laminating the pixel electrode of the substrate and the transfer layer of the transfer donor substrate, the laser X is irradiated to a predetermined portion of the base layer surface of the donor substrate.

Thereafter, as shown in FIG. 1B, the transfer layer is transferred from the donor substrate to the pixel electrode 160 of the substrate to form an organic light emitting layer pattern 204 ′ on the substrate. Subsequently, the organic light emitting display device may be manufactured by forming the upper electrode 180 as a common electrode on the organic emission layer pattern 204 ′.

At this time, in the process of adhering the donor substrate to the substrate, when the donor substrate is not tightly adhered to the substrate due to the step difference of the substrate and the transfer layer is transferred onto the substrate, an open defect (E) in which the organic layer is opened. This may occur. That is, the organic film is not properly transferred to the edge portion of the substrate and the organic film is cut, thereby causing a defect.

In addition, in order to improve characteristics of the organic light emitting display device, the organic layer may be formed as a multilayer film including at least one of a hole injection layer, a hole transport layer, a hole suppression layer, an electron transport layer, and an electron injection layer. In general, the organic layer except for the light emitting layer may be formed by a spin process or a deposition as a common layer. In this case, the organic layer may also be formed in the encapsulation portion of the display device during the manufacturing process of the organic light emitting display device. have.

Therefore, the organic layer is present in the sealing portion, a problem that the adhesive strength of the sealant is weakened. As the adhesive force of the sealant is weakened, external gas and moisture may be introduced into the organic light emitting display device, and the introduced external gas and moisture may shorten the lifespan of the light emitting layer in the display device. There is a problem that can cause a defect.

Conventionally, although the organic film is removed by a physical cleaning process, it may cause damage to the wiring in the encapsulation part, which may cause another defect.

The technical problem to be achieved by the present invention, in the manufacturing process of the organic light emitting display device, by using a UV-curable polymer in the organic film to easily remove the organic film present in the encapsulation portion to enhance the adhesive strength of the sealant and organic light emitting display device It is an object to protect the light emitting element inside.

In addition, in the manufacturing process of the organic light emitting display device, the use of a polymer as the organic film layer is to provide a flattening function to reduce the irregularities of the substrate to improve the stability of the organic light emitting display device.

The present invention to achieve the above object

Providing an insulating substrate having a first electrode formed thereon;

Forming a first organic film on the first electrode as a common layer over the entire surface of the insulating substrate;

Curing the first organic film except for the first organic film formed on the encapsulation portion on the insulating substrate;

Removing the first organic film of the encapsulation part;

Forming an organic light emitting layer patterned by a region thermal transfer method in the pixel region on the first organic film;

It provides a method of manufacturing an organic light emitting display device comprising the step of forming a second electrode which is a common electrode on the organic light emitting layer.

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

2A through 2E are diagrams for describing a method of manufacturing an organic light emitting display device according to an exemplary embodiment of the present invention.

As shown in FIG. 2A, an insulating substrate 10 having a first electrode 11 formed on a pixel area is provided. The first electrode may be an anode electrode or a cathode electrode.

When the first electrode 11 is an anode electrode, a metal having a high work function is a transparent electrode made of ITO or IZO, or a group consisting of Pt, Au, Ir, Cr, Mg, Ag, Ni, Al, and alloys thereof It may be a reflective electrode selected from.

In addition, when the first electrode 11 is a cathode, a metal having a low work function is selected from the group consisting of Mg, Ca, Al, Ag, Ba, and alloys thereof. It may be an electrode.

A first organic film 12 is formed on the first electrode over the entire surface of the insulating substrate.

Here, the first organic layer may be a hole injection layer, a hole transport layer or a double layer thereof or an electron injection layer, an electron transport layer or a double layer thereof having a UV reactive functional group.

That is, the first organic layer is a hole injection layer, a hole transport layer or a double layer thereof or a UV reactive functional group introduced into a single molecule or polymer having respective properties for forming an electron injection layer, an electron transport layer or a double layer thereof It has a structure in which molecules or polymers are bound. For example, the hole transport layer is UV reactive to N-diphenyl-N, N'-bis (4-methylphenyl) -1,1'-biphenyl-4,4'-diamine, which is a commonly used hole transport material. Functional groups may be bound. Here, the UV reactive functional group may include one of an acrylate group, a vinyl group, and an epoxy group.

The hole transport layer may be represented by the following formula (1).

<Formula 1>

Here, in Formula 1, R1 to R8 are hydrogen, fluorine, or an alkyl group having various chain lengths, which may be the same as or different from each other, and at least one has a UV reactive functional group. In this case, the UV reactive functional group may include one of an acrylate group, a vinyl group, and an epoxy group.

More specifically, it may be represented by the following Chemical Formulas 2 to 4.

<Formula 2>

<Formula 3>

<Formula 4>

Here, in Formulas 2 to 4, R and Rl to R8 are hydrogen, fluorine, or an alkyl group having various chain lengths, and may be the same as or different from each other.

The first organic layer may be formed by one method selected from the group consisting of a spray coating method, a dip coating method, a bar coating, a gravure coating method, a roll coating method, and a spin coating method.

As a result, the first organic layer is formed of a polymer, and is formed in the pixel region on the first electrode to planarize the uneven structure of the substrate, thereby forming an edge of the light emitting layer by laser thermal transfer, which is a subsequent process. It can alleviate the open phenomenon.

Subsequently, as shown in FIG. 2B, the mask 13 is irradiated with UV to cure portions other than the encapsulation portion a, and then the encapsulation portion a is cleaned by washing with an organic solvent or the like. Remove the first organic film formed in the).

Subsequently, as shown in FIG. 2C, donor substrates 20R, 20G, and 20B formed of a base layer 21, a light-to-heat conversion layer 22, and a transfer layer 23R, 23G, and 23B may be connected to the pixel region of the substrate. After arranging to face the laser, the organic light emitting layer pattern 23 is formed in each pixel region as shown in FIG. 2D.

Next, as shown in FIG. 2D, a second electrode 24 is formed on the organic light emitting layer pattern as a common layer over the entire surface of the substrate.

The second electrode 24 is a conductive metal having a low work function and is a material selected from the group consisting of Mg, Ca, Al, Ag, and alloys thereof, or a transparent electrode having a thin thickness or a reflective electrode having a thick thickness. Is formed.

In the case where the second electrode 24 is an anode electrode, a metal having a high work function is a transparent electrode made of ITO or IZO, or Pt, Au, Ir, Cr, Mg, Ag, Ni, Al, and these. It may be a reflective electrode made of an alloy of.

In the present invention, a second organic layer may be further included between the organic light emitting layer pattern 23 and the second electrode 24.

Here, the second organic film may be a hole injection layer, a hole transport layer or a double layer thereof or an electron injection layer, an electron transport layer or a double layer thereof having a UV reactive functional group. That is, the second organic film is a UV injection functional group to a single molecule or a polymer having the respective characteristics for forming the hole injection layer, hole transport layer or a double layer thereof or an electron injection layer, an electron transport layer or a double layer thereof as described above Has a structure in which a single molecule or a polymer is introduced

The second organic layer may be formed at the same time by selecting one of spray coating, dip coating, bar coating, gravure coating, roll coating, spin coating and deposition. Can be.

Subsequently, as shown in FIG. 2E, after the sealant 32 is formed at the edge of the encapsulant 30 to which the moisture absorbent 31 is attached to remove moisture therein, the encapsulation portion a of the substrate 30 is formed. ) And the sealant of the SUS can, and then cured with heat or ultraviolet rays to encapsulate the encapsulant and the back surface of the substrate 30 to the outside to manufacture the organic light emitting display device.

In addition, the adhesion between the encapsulant and the substrate 30 may be improved by removing the organic layer of the encapsulation portion a.

As described above, according to the present invention, as the first organic film for improving the characteristics of the organic light emitting layer is applied to the UV curable polymer, the organic EL display device can be manufactured more stabilized by the flattening function to alleviate the unevenness of the substrate. have.

In addition, the present invention can manufacture an organic light emitting display device that can control the occurrence of defects of the pixel by strengthening the adhesion between the encapsulant and the substrate by safely removing the organic film formed on the encapsulation portion.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

Claims (12)

Providing an insulating substrate having a first electrode formed thereon; Forming a first organic film on the first electrode as a common layer over the entire surface of the insulating substrate; Curing the first organic film except for the first organic film formed on the encapsulation portion on the insulating substrate; Removing the first organic film of the encapsulation part; Forming an organic light emitting layer patterned by a region thermal transfer method in the pixel region on the first organic film; And forming a second electrode as a common electrode on the organic light emitting layer. The method of claim 1, And the first electrode is an anode electrode or a cathode electrode. The method of claim 1, And the first organic layer is a hole injection layer, a hole transport layer, or a double layer thereof, or an electron injection layer, an electron transport layer, or a double layer thereof. The method of claim 3, wherein The first organic film is a method of manufacturing an organic light emitting display device, characterized in that a UV reactive functional group is introduced. The method of claim 4, wherein The UV reactive functional group is a method of manufacturing an organic light emitting display device, characterized in that one selected from an acrylate group (acrylate group), a vinyl group (vinyl group) and an epoxy group (epoxy group). The method of claim 1, The first organic layer is a method of manufacturing an organic light emitting display device, characterized in that formed by selecting one of the spray coating method, dip coating method, bar coating, gravure coating method, roll coating method and spin coating method. The method of claim 1, The organic light emitting display device may further include forming a second organic film on the organic light emitting layer, curing the second organic film except for an encapsulation part, and then removing the second organic film of the encapsulation part. A method of manufacturing an organic light emitting display device. The method of claim 7, wherein And the second organic layer is a hole injection layer, a hole transport layer, or a double layer thereof, or an electron injection layer, an electron transport layer, or a double layer thereof. The method of claim 8, The second organic film is a method of manufacturing an organic light emitting display device, characterized in that the UV reactive functional group is introduced. The method of claim 9, The UV reactive functional group is a method of manufacturing an organic light emitting display device, characterized in that one of an acrylate group (acrylate group), a vinyl group (vinyl group) and an epoxy group (epoxy group). The method of claim 7, wherein The second organic film is formed at the same time in the step of forming one of the method selected from the spray coating method, dip coating method, bar coating method, gravure coating method, roll coating method, spin coating method and the deposition method or forming the light emitting layer A method of manufacturing an organic light emitting display device. An organic light emitting display device manufactured by the method of claim 1.

Images