KR20070049942A - Method for fabricating the oled display panel - Google Patents

Abstract

Provided is a method of manufacturing an LED display panel that can seal a panel using passivation. A method of manufacturing an LED display panel includes (a) forming a lower electrode pattern on a substrate, and (b) exposing an insulator to define a pixel region by exposing a portion of the lower electrode pattern on a substrate on which the lower electrode pattern is formed. Forming a first separator on the insulator between the pixel regions, the first separator having a longitudinal direction perpendicular to the length direction of the lower electrode pattern; and (d) an upper surface of the first separator on the first separator. Forming a second separator having a width longer than a width of an upper surface of the first separator so as to overlap with the first separator, the second separator being attached to the first separator to facilitate separation from the first separator; Forming a light emitting organic layer on the exposed lower electrode pattern, (f) forming an upper electrode on the light emitting organic layer, (g) leaving the second separator away from the first separator, and (h) On the structure formed by the step Conformally forming a passivation film.

OLED, OLED, first separator, second separator, passivation

Description

Method for fabricating the OLED display panel

1 is a process flowchart illustrating a method of manufacturing an LED display panel according to an embodiment of the present invention.

2A through 2H illustrate process cross-sectional views according to each process step of FIG. 1.

<Explanation of symbols for the main parts of the drawings>

200: substrate 210: lower electrode pattern

220: insulator 231: first separator

232: second separator 240: luminescent organic layer

250: upper electrode 300, 400: roller

The present invention relates to a method of manufacturing an OLED display panel, and more particularly, to an organic film and an inorganic material, not an encapsulation method using a glass can or a stainless steel can to block moisture or oxygen to the ODL element. The present invention relates to a method for manufacturing an LED display panel by manufacturing an OLED display panel by a passivation method using a film, but to solve the difficulty in depositing a passivation film due to the reverse tapered separator.

OLED stands for Organic Light Emitting Diode, and refers to a self-luminous display that emits light by electrically exciting a luminescent organic compound.

OLED can be operated at low voltage and eliminates the drawbacks of LCDs such as thinning, wide viewing angles, and fast response speeds.It is equivalent to or better than TFT-LCD in medium size and lower than other display devices. It is attracting attention as a next-generation display that has advantages such as being able to have a simple manufacturing process and advantageous in future price competition.

The OLED is formed of an organic luminescent material in a space between a lower plate having a form in which an ITO transparent electrode pattern is formed as a positive electrode on a transparent glass substrate and an upper plate in which a metal electrode is formed as a negative electrode on the substrate. And a display device that emits light while a current flows through the organic light emitting material when a predetermined voltage is applied between the metal electrode and the metal electrode.

In spite of the above advantages, OLED has a short life span due to the degradation of OLED element due to the organic layer or the light emitting layer made of polymer reacts with surrounding oxygen, moisture, or other environmental factors. The disadvantage is losing. In particular, metal electrodes used as cathodes of light emitting devices are easily oxidized when exposed to moisture or oxygen, resulting in rapid change in properties.

In order to overcome such disadvantages and to ensure the stability of ODL, various attempts, technical research and development are being made. Until now, in the industry, a metal cap or glass cap attached with calcium oxide (CaO), barium oxide (BaO), etc. as a desiccant in consideration of process ease has been applied to ultraviolet (UV) curable epoxy-based substrates. As a method of attaching to an OLED element using an epoxy-based adhesive, a method of blocking the permeation of moisture and oxygen to suppress the degradation of the OLED is employed.

When encapsulating an ODL element using a metal cap or a glass cap, it is difficult to reduce the weight and thickness of the device, and in particular, there is a disadvantage in that it is impossible to implement a next-generation light emitting device that can be bent by the metal cap.

In order to solve this problem, various methods, such as encapsulation using a plastic cap, are not encapsulated using a metal cap or a glass cap (Korean Patent Publication No. 1999-88334), and a shield glass A method of blocking moisture, oxygen, and the like by filling a silicon oil between the device and the shield after being covered with (S. Patent No. 5962962) has been proposed.

However, both of these methods still have problems to thin the device (less than 3 mu m).

Accordingly, in order to solve all these problems, a method of forming an inorganic layer and an organic layer on the OLED element on which the cathode metal electrode is formed to form an overall structure to seal the entire element to prevent penetration of moisture and oxygen, that is, passivation ( Passivation methods have been proposed.

In the above, "conformally" means that it is in contact with the entire surface of the coating layer and is applied to maintain the shape of the coating layer as it is.

Representative examples of sealing an ODL device using such a passivation method are Korean Patent Publication No. 2003-82256 (encapsulation thin film having an adhesive organic-inorganic composite film and an organic electroluminescent device comprising the same) and 2004-7017534 ( Barrier coating and a method of manufacturing the same), all of which are formed by forming a passivation layer made of a combination of organic-inorganic films on an OLED device having a cathode metal electrode forming process without using a separate metal cap or glass cap. The same effect as the encapsulation method using a cap or glass cap can be obtained.

However, the above methods are invented for the application to the Active Matrix OLED (AM-OLED), and in the case of applying the technology to the passive OID, the reverse taper type separator. Due to the gaps, the adhesion is reduced or it is very difficult to conformally deposit overall.

In addition, when a gap is formed between the reverse tapered separator and the passivation film, external moisture or oxygen may penetrate into the gap.

The technical problem to be achieved by the present invention is to encapsulate the ODL element through a passivation method formed by stacking several layers of organic-inorganic layers on an ODL element on which a cathode metal electrode is formed, rather than an encapsulation method using a glass cap or a metal cap. The present invention provides a method for manufacturing an ODL display panel that can replace the inverted tapered separator that is a problem.

Technical problems to be achieved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description.

In order to solve the above technical problem, a method of manufacturing an LED display panel according to an embodiment of the present invention includes (a) forming a lower electrode pattern on a substrate, and (b) a lower electrode on a substrate on which a lower electrode pattern is formed. Forming an insulator to define a pixel region by exposing a portion of the pattern, (c) forming a first separator on the insulator between the pixel regions, the length of which is perpendicular to the length of the lower electrode pattern; (d) has a width longer than the width of the top surface of the first separator to overlap the top surface of the first separator on the first separator, and is attached to the first separator to facilitate separation from the first separator Forming a second separator, (e) forming a light emitting organic layer on the exposed lower electrode pattern of the pixel region, (f) forming an upper electrode on the light emitting organic layer, (g) a second separator To the first separator It includes the step of leaving, and (h) to form the cone to a foam structure formed by the above step a passivation film.

Specific details of other embodiments are included in the detailed description and the accompanying drawings.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, only the present embodiments to make the disclosure of the present invention complete, and common knowledge in the art to which the present invention pertains. It is provided to fully inform the person having the scope of the invention, which is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

In addition, in the drawings, the size and thickness of layers and films or regions are exaggerated for clarity of description, and when any film or layer is described as being formed "on" of another film or layer, It may be directly on top of the other film or layer, and a third other film or layer may be interposed therebetween.

1 is a process flow chart illustrating a method of manufacturing an LED display panel according to an embodiment of the present invention, Figures 2a to 2h is a process cross-sectional view according to each process step of FIG.

In order to manufacture the LED display panel according to an embodiment of the present invention, first, as shown in FIG. 2A, a lower electrode pattern 210 is formed on the substrate 200 (S110).

The substrate 200 becomes a base layer of the OLED display panel 20 of the present invention, and in the case of a bottom emission type and a dual emission OLED display panel, the substrate 200 is made of glass. Transparent substrates are used, and in the case of top emission, silicon substrates are used.

The lower electrode pattern 210 is an electrode used as an anode and is formed with a stripe pattern on the substrate 200.

The lower electrode pattern 210 is formed of a transparent material such as indium tin oxide (ITO) in the case of the bottom emission type and the bidirectional emission type, but is formed using a metal material in the case of the top emission type.

In order to form the lower electrode pattern 210, a conductive material is coated on the entire substrate 200 and patterned using a photo-etching process to have a predetermined pattern (stripe pattern).

Next, as shown in FIG. 2B, an insulator 220 is formed on the transparent substrate 200 on which the lower electrode pattern 210 is formed (S120).

The insulator 220 is formed conformally on the substrate 200 on which the lower electrode pattern 210 is formed, but is formed in a partial region of the lower electrode pattern 210 where a pixel area is to be defined. Not. That is, the lower electrode pattern 210 is exposed between the insulators 220 formed in the region where the pixel region is to be defined.

The insulator 220 may be formed by photo-etching an inorganic material such as SiOx and SiNx, but is generally formed through a photo-development process using a photoresist.

Next, as shown in FIG. 2C, a first separator 231 is formed on the insulator 220 (S130).

The first separator 231 is generally formed through a photo-development process using a photoresist, and the cross-sectional shape thereof is tapered (a tapered end shape or a trapezoidal cross-sectional shape). It may have one of square, rectangular shape, but is preferably formed in a tapered shape.

The first separator 231 is formed on the insulator 220 between the pixel regions in which the exposed lower electrode pattern 210 is present, and the length of the first separator 231 is perpendicular to the length direction of the lower electrode pattern 210. .

Next, as shown in Figure 2d to form a second separator 232 (S140).

In this case, the second separator 232 may be adhered to the first separator 231, that is, the first separator 231 may have a strength that can be detached when any physical force is applied later. Is formed on the phase.

In addition, the second separator 232 has a width longer than the width of the top surface of the first separator 231 so as to completely overlap the top surface of the first separator 231.

The process of forming the second separator 232 on the first separator 231 may include a roll coater or a gravure printing method (gravure printing uses a photographic technique during concave plate printing. It can be carried out by the electronic rotary engraving and the laser-printed concave plate to print in the R rotary method), it is preferable to use a roll coater.

3 is a view illustrating a method of forming the second separator 232 using a roll coater.

As shown in FIG. 3, the second separator 232 has a constant adhesiveness on the surface thereof and is wound on the roller 300, and the second separator 232 is rotated on the first separator 231 one by one as the roller 300 rotates. The separator 232 is formed by sticking.

Referring back to the manufacturing method of the LED display panel according to an embodiment of the present invention, the light emitting organic layer 240 is formed on the exposed lower electrode pattern 210 as shown in Figure 2e (S150) .

The light emitting organic layer 240 is actually formed on the OLED display panel and is formed on the lower electrode substrate 210 exposed between the insulators 220 by evaporation.

Next, as illustrated in FIG. 2F, an upper electrode 250 is formed on the light emitting organic layer 240 (S160).

The upper electrode 250 is an electrode used as a cathode of an LED panel according to an embodiment of the present invention, and in the case of a bottom emission type, sputtering metals such as Al, Cr, Ag, and Ni. In the case of top emission, it is formed using a transparent electrode such as ITO.

In forming the upper electrode 250, a mask of the second separator 232, that is, the upper electrode 250 completely covers the surfaces of the first separator 231 and the second separator 232. It does not cover, so that there is a broken portion in the middle, the first separator 231 and the second separator 232 electrically separates the upper electrode 250 on both sides of the longitudinal direction, which is the second This is possible because the width of the separator 232 is greater than the width of the upper surface of the first separator 231.

Next, as shown in FIG. 2G, the second separator 232 is separated from the first separator 231 (S170).

In the process of detaching the second separator 232 from the first separator 231, since the second separator 232 is adhered to the first separator 231, a force stronger than the adhesive force may be applied to the second separator 231. When applied to the sieve 232, the second separator 232 is separated from the first separator 231.

4 illustrates a preferred embodiment for separating the second separator 232 from the first separator 231.

As shown in FIG. 4, in order to separate the second separator 232 from the first separator 231, it is preferable to use the roller 400 in consideration of the process speed, that is, the surface of the roller 400 may be removed. 2 The separator 232 is coated with a material having a stronger adhesive force or adhesive force than the adhesive force adhered to the first separator 231, and the roller 400 is in close contact with the upper surface of the second separator 232 The second separator 232 is separated from the first separator 231.

Next, as shown in FIG. 2H, a passivation layer 260 formed of a combination of a certain organic material and inorganic material is conformally formed on the structure formed by the above step (see 40 of FIG. 4G). In this case, the manufacturing process of the LED display panel according to the embodiment of the present invention is terminated.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above embodiments but may be manufactured in various forms, and having ordinary skill in the art to which the present invention pertains. It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without changing the technical spirit or essential features of the present invention. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

According to the manufacturing method of the LED display panel according to the embodiment of the present invention by presenting a separator of the LED display panel that can replace the conventional reverse tapered separator used in the yen using a relatively thick glass cap or metal cap Instead of the encapsulation method, the encapsulation process using a passivation layer made of a combination of organic and inorganic materials that can be manufactured in a thin form becomes possible.

Claims (6)

(a) forming a lower electrode pattern on the substrate; (b) forming an insulator on the substrate on which the lower electrode pattern is formed to expose a partial region of the lower electrode pattern to define a pixel region; (c) forming a first separator on the insulator between the pixel regions, the first separator having a longitudinal direction perpendicular to the longitudinal direction of the lower electrode pattern; (d) the first separator having a width longer than the width of the top surface of the first separator so as to overlap the top surface of the first separator on the first separator, and to facilitate separation from the first separator; Forming a second separator formed by sticking to the second separator; (e) forming a light emitting organic layer on the exposed lower electrode patterns of the pixel region; (f) forming an upper electrode on the light emitting organic layer; (g) leaving the second separator away from the first separator; And (h) forming a passivation film conformally on the structure formed by the step. The method of claim 1, The first separator is a method of manufacturing an LED display panel, characterized in that formed by a photo-development process using a photosensitive film. The method of claim 1, The cross-sectional shape of the first separator is a tapered, square, rectangular, characterized in that the manufacturing method of the LED display panel. The method of claim 1, The step (d) is a manufacturing method of the LED display panel, characterized in that carried out using a roll coater or gravure printing method. The method of claim 1, In the step (g), a material having a stronger adhesive force or adhesion than the adhesive force of the second separator adhered to the first separator is applied to the roller, and the roller is brought into close contact with the upper surface of the second separator to physically And separating the second separator from the first separator. The method of claim 1, The passivation film is a manufacturing method of the LED display panel, characterized in that it comprises at least one layer of each of the organic layer and the inorganic layer.

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