KR20040106058A - Organic electro luminescence display and method for fabricating the same - Google Patents

Abstract

PURPOSE: An organic electroluminescence display and a method are provided to easily remove an organic film, by forming an auxiliary film for removing the organic film on an encapsulation portion. CONSTITUTION: An organic electroluminescence display comprises an anode electrode(110) formed on a lower insulation substrate(100); a pixel defining film(140) formed all over the lower insulation substrate such that a portion of the anode electrode is opened; an organic light emitting layer(150) formed at the opening of the anode electrode; a cathode layer(160) formed on the organic light emitting layer; an upper insulation substrate(180) for encapsulating the anode electrode, organic light emitting layer, and the cathode electrode; and an auxiliary film(120,130) formed on a cathode contact of the lower insulation substrate and an encapsulation portion.

Description

Organic electroluminescent display and manufacturing method thereof {Organic electro luminescence display and method for fabricating the same}

The present invention relates to an organic electroluminescent display and a method of manufacturing the organic electroluminescent display, and more particularly, to an organic electroluminescence which more easily removes a polymer organic layer at a junction by forming a removal auxiliary layer at a cathode contact and an encapsulation junction of an organic electroluminescent display. A display device and a method of manufacturing the same.

In the organic electroluminescent display device, when a polymer material is used as the organic electroluminescent layer, the organic electroluminescent layer is generally formed on the substrate through spin coating. However, when the organic electroluminescent layer is formed through spin coating, the organic film is formed in regions other than the pixel portion. Therefore, in order to seal the internal structure of the organic light emitting display device, it is necessary to remove the organic layer of the encapsulation junction.

In the related art, a cleaning process using an organic solvent was performed to remove the organic film of the encapsulation junction. However, the cleaning process is less accurate, and the organic solvent penetrates and is highly likely to damage the pixel portion.

To solve this problem, a method of removing foreign matter on a substrate using a laser is used. Korean Laid-Open Patent Publication No. 2000-0036020 discloses a method for removing foreign substances on the surface of a substrate using a laser. The foreign material removal method using the laser is a method of removing organic or inorganic foreign matter on the substrate by irradiating the UV laser directly on the surface of the substrate.

However, in the case of the conventional board | substrate, it is common for the sealing junction part to laminate | stack a metal wiring and a passivation layer on a glass substrate. However, the laser energy absorption rate of the passivation film is small, so that the organic film is hardly removed.

Referring to FIG. 1, in the method of removing foreign matter on a substrate using a conventional laser, as the number of pulses of the laser increases, the thinner the thickness of the remaining organic film is reduced, the less the amount of shaving is reduced, and thus no residue is left. It can be seen that a large amount of energy is required for removal.

Therefore, the conventional method of removing foreign matters by the laser may damage the substrate, and consumes a lot of energy compared to the removal effect.

An object of the present invention is to solve the above-mentioned problems of the prior art, the present invention forms an auxiliary film for removing the organic film that does not damage itself while absorbing the laser energy well in the sealing junction to remove the organic film with low energy An object of the present invention is to provide an organic electroluminescent display device.

BRIEF DESCRIPTION OF THE DRAWINGS The graph which shows the relationship between the residual organic film and a laser of the conventional sealing junction part.

2 is a plan view illustrating an organic light emitting display device according to a preferred embodiment of the present invention.

3A to 3D are cross-sectional views of an organic light emitting display device according to a preferred embodiment of the present invention.

4 is a graph showing the relationship between the residual organic film and the laser of the sealing junction of the present invention.

(Explanation of symbols for main parts of drawing)

100: lower insulating substrate 110; Anode electrode

120, 130; Auxiliary membrane 140; Pixel Definition Film

150; An organic electroluminescent layer 160; Cathode electrode

170; Sealing adhesive 180; Upper insulation board

A; Cathode contact B; Bag joint

The present invention for achieving the above object is an anode electrode formed on the lower insulating substrate; A pixel defining layer formed to open a portion of the anode electrode over an entire surface of the lower insulating substrate; An organic light emitting layer formed in the opening of the anode electrode; A cathode electrode formed on the organic light emitting layer; And an upper insulating substrate for encapsulating the anode electrode, the organic light emitting layer, and the cathode electrode, and including an auxiliary layer formed on the cathode contact and the encapsulation junction of the lower insulating substrate.

In an embodiment of the present invention, the auxiliary film is preferably an auxiliary film for removing the organic film formed on the cathode contact and the encapsulation junction, it is made of the same material as the anode electrode made of ITO, IZO or ICO, or an acrylic photoresist or It is preferable that it is made of the same material as the pixel defining layer made of polyimide.

Alternatively, the auxiliary film is preferably made of a material having a higher absorption rate than the organic film at a laser wavelength used for removing the organic film, or a material having a higher laser energy density for removal than the organic film.

In addition, the present invention comprises the steps of forming an anode electrode on the lower insulating substrate; Forming a pixel defining layer to open a portion of the anode electrode over an entire surface of the lower insulating substrate; Forming an organic electroluminescent layer in the opening of the anode; Forming a cathode on the organic electroluminescent layer; Forming an upper insulating substrate for encapsulating the anode electrode, the organic electroluminescent layer, and the cathode electrode, and forming an auxiliary layer on the cathode contact and the encapsulation junction; And removing an organic layer of the cathode contact and the encapsulation junction after the organic electroluminescent layer is formed in the pixel portion.

In a preferred embodiment of the present invention, the auxiliary film is preferably an auxiliary film for removing the organic film formed on the cathode contact and the sealing junction.

The auxiliary layer is preferably formed at the same time as the anode electrode made of ITO, IZO or ICO, or at the same time as the pixel defining layer made of acrylic photoresist or polyimide.

Alternatively, after forming the pixel defining layer, the auxiliary layer is formed of a material having a higher absorption rate than that of the organic film at a wavelength of a laser used to remove the organic film, and a material having a higher laser energy density than that of the organic film. It is preferable that it consists of.

The organic film removing process removes the organic film on the auxiliary film using a laser, and the laser has an energy density of 75 J / cm 2 or more, and more preferably, the laser has an energy density of 125 J / cm 2 or more.

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

2 is a plan view illustrating an organic light emitting display device according to a preferred embodiment of the present invention.

3A through 3D are cross-sectional views illustrating an organic light emitting display device according to an exemplary embodiment of the present invention.

4 is a graph showing the relationship between the residual organic film and the laser of the sealing junction of the present invention.

Example 1

Referring to FIG. 3A, a pixel portion is formed by depositing and patterning a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), and indium cesium oxide (ICO) on a glass substrate as a lower insulating substrate 100. A transparent anode electrode 110 is formed on the substrate.

While forming the anode electrode 110, an auxiliary layer for removing the same organic film as the anode electrode 110 material on the cathode contact A and the encapsulation junction B of the lower insulating substrate 100 is provided. Films 120 and 130 are formed.

An anode electrode 110 of the pixel portion, an auxiliary layer 120 on the cathode contact A, and an auxiliary layer 130 on the encapsulation junction B are formed, and then the anode electrode over the entire lower insulating substrate 100. The pixel defining layer 140 is formed to open a portion of the 110. The pixel defining layer 140 is made of a polymer such as acrylic photoresist or polyimide and an inorganic material.

Then, the organic electroluminescent layer 150 is formed in the opening of the anode electrode 110 of the pixel portion. The organic electroluminescent layer 150 may be formed through spin coating, and may include a hole injection layer (HIL), a hole transport layer (HTL), an emission layer, an electron transport layer (ETL), and an electron injection layer (EIL). It has a multilayer structure of at least one layer or more. At this time, since the organic electroluminescent layer 150 is formed through spin coating, the organic layer is also formed on the cathode contact A and the encapsulation junction B. FIG.

Referring to FIG. 3B, after forming the organic EL layer 150, the organic layers of the cathode contact A and the encapsulation junction B of the substrate are removed by using the auxiliary layers 120 and 130. It is preferable to use a laser for the process of removing the said organic film. In addition, the laser can be used from UV (excimer laser, Nd: YAG laser, etc.) to IR (Nd: YAG, CO2 laser, etc.) depending on the light source material.

After removing the organic layer on the auxiliary layer A, a conductive material is deposited and patterned on the substrate to form the cathode electrode 160. The cathode electrode 160 serves as a metal electrode to smoothly transfer electrons to the electron transport layer using electrodes having a low work function, such as Al, Mg: Ag, and Ca.

Referring to FIGS. 3C and 3D, after the cathode electrode 160 is formed, the encapsulation junction A of the anode electrode 110, the organic electroluminescent layer 150, and the cathode electrode 160 is encapsulated. The upper insulating substrate 180 is formed using the sealing adhesive 170.

Referring to FIG. 4, in the method of removing foreign matters on the substrate 100 using the auxiliary films 120 and 130 of the present invention, the organic film may be linearly increased as the number of pulses increases when the energy density of the laser is 75 J / cm 2 or more. It can be seen that the number of pulses required is also reduced.

When the energy density is 75 J / cm 2, the organic film starts to be shaved when the number of pulses is 8 or more, and the maximum value is shown when the number of pulses is 12.

In the case where the energy density is 100 J / cm 2, the number of pulses starts to be shaved at 1, and the maximum value is shown at 2.

More preferably, it can be seen that the removal depth of the organic film shows the maximum value at the same time as the laser irradiation at the energy density of 125 J / cm 2 or more.

That is, when the organic film is removed by laser using the auxiliary film for removing the organic film of the present invention, it can be seen that the energy required for the removal is small.

Example 2

The auxiliary films 120 and 130 of the first embodiment are formed using the pixel defining layer 140.

The pixel defining layer 140 may be deposited and patterned to form the pixel defining layer 140, and at the same time, auxiliary layers 120 and 130 may be formed to remove the organic layers in the cathode contact A and the encapsulation junction B. FIG. .

Example 3

After the pixel defining layer 140 is formed in Example 1, a material having a higher laser energy absorption rate than the organic layer is deposited and patterned at the laser wavelength used in the process of removing the organic layer to encapsulate the cathode contact A and the encapsulation layer. Auxiliary layers 120 and 130 are formed in the junction portion B.

Alternatively, auxiliary layers 120 and 130 are formed using a material having a higher laser energy density than that of the organic layer.

As described above, the present invention is an additional process in the case of using the pixel electrode material (ITO, IZO, ICO, etc.) or the pixel defining layer 140 material (acrylic photoresist, polyimide, etc.) as the auxiliary film (120, 130) In the case of forming the auxiliary layers 120 and 130, the material may be selected according to the laser light source so that various light sources may be used.

In addition, the auxiliary layers 120 and 130 not only help to remove the organic layer but also serve as a protective layer of the lower layer during the laser removal process.

According to the present invention as described above, the present invention provides an organic electroluminescent display device that can form an auxiliary film for removing the organic film in the encapsulation junction, it is possible to more easily remove the organic film generated in the encapsulation junction when forming the organic film. can do.

In addition, the present invention can provide a method of manufacturing an organic light emitting display device in which the pixel portion is not damaged by removing the organic layer using the auxiliary layer and the laser.

While the foregoing has been described with reference to preferred embodiments of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. It will be appreciated.

Claims (15)

An anode electrode formed on the lower insulating substrate; A pixel defining layer formed to open a portion of the anode electrode over an entire surface of the lower insulating substrate; An organic light emitting layer formed in the opening of the anode electrode; A cathode electrode formed on the organic light emitting layer; An upper insulating substrate for encapsulating the anode electrode, the organic light emitting layer, and the cathode electrode; And an auxiliary layer formed on the cathode contact and the encapsulation junction of the lower insulating substrate. The method of claim 1, And the auxiliary layer is an auxiliary layer for removing an organic layer formed on a cathode contact and an encapsulation junction. The method of claim 1, And the auxiliary layer is formed of the same material as an anode electrode made of ITO, IZO, or ICO. The method of claim 1, And the auxiliary layer is made of the same material as the pixel defining layer made of acrylic photoresist or polyimide. The method of claim 1, And the auxiliary layer is formed of a material having a higher absorption rate than the organic layer at a laser wavelength used to remove the organic layer. The method of claim 1, And the auxiliary layer is formed of a material having a higher laser energy density than that of the organic layer. Forming an anode electrode on the lower insulating substrate; Forming a pixel defining layer to open a portion of the anode electrode over an entire surface of the lower insulating substrate; Forming an organic electroluminescent layer in the opening of the anode; Forming a cathode on the organic electroluminescent layer; Forming an upper insulating substrate for encapsulating the anode electrode, the organic electroluminescent layer, and the cathode electrode, Forming an auxiliary film on the cathode contact and the encapsulation junction; And removing the organic layer of the cathode contact and the encapsulation junction after the organic electroluminescent layer is formed in the pixel portion. The method of claim 7, wherein And the auxiliary layer is an auxiliary layer for removing an organic layer formed on a cathode contact and an encapsulation junction. The method of claim 7, wherein And the auxiliary layer is formed simultaneously with an anode electrode made of ITO, IZO, or ICO. The method of claim 7, wherein And the auxiliary layer is formed simultaneously with a pixel defining layer made of acrylic photoresist or polyimide. The method of claim 7, wherein And the auxiliary layer is formed of a material having a higher absorption rate than the organic layer at a wavelength of a laser used to remove the organic layer after the pixel defining layer is formed. The method of claim 7, wherein And after the pixel defining layer is formed, the auxiliary layer is formed of a material having a higher laser energy density than that of the organic layer. The method of claim 7, wherein The organic film removing step of removing the organic film on the auxiliary film using a laser manufacturing method of the organic light emitting display device. The method of claim 13, And the laser has an energy density of 75 J / cm 2 or more. The method of claim 14, And said laser has an energy density of at least 125 J / cm 2.