KR20070118744A - Organic electro-luminescence display and fabricating method thereof - Google Patents

Abstract

An organic electro-luminescence display and a method for fabricating the same are provided to prevent an inlet of a nozzle from clogging by delaying time when color liquid is hardened. An organic electro-luminescence display includes a stage(94), and a surface head(80). A substrate is loaded on the stage. Color liquid is transmitted to the substrate through an end of a nozzle when the surface head with a plurality of nozzles is in contact with the substrate. The organic electro-luminescence display further includes an align mark and a vision system for aligning the stage and the surface head. At least one of the surface head and the stage is used up/down/left/right.

Description

Organic electroluminescent display and manufacturing method thereof {ORGANIC ELECTRO-LUMINESCENCE DISPLAY AND FABRICATING METHOD THEREOF}

1 is a cross-sectional view illustrating an organic light emitting display device according to the present invention.

2 and 3 are perspective views illustrating an apparatus for manufacturing an organic field display device according to the present invention.

4A to 4E are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to the present invention.

<Brief description of symbols for the main parts of the drawings>

20 substrate 22 gate electrode

24 gate insulating film 26 active layer

28 source electrode 30 drain electrode

32: ohmic contact layer 34: protective film

36: anode 38: partition

40, 40a, 40b, 40c: organic light emitting layer 42: cathode

70: nozzles 80, 80a, 80b, 80c: face head

R: Red G: Green

B: blue

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light emitting display device, and more particularly, to an organic light emitting display device and a method of manufacturing the same for preventing defects caused by a printing method.

Video display device that implements a variety of information on the screen is a key technology in the information and communication era, and is developing in a direction of thinner, lighter, portable and high performance. Accordingly, flat panel display devices such as organic light emitting display devices that can reduce weight and volume, which are disadvantages of cathode ray tubes (CRTs), have been in the spotlight. Here, the organic light emitting display device is a self-luminous device using a thin organic light emitting layer between electrodes, and has an advantage of thinning like a paper.

The organic light emitting display device is classified into a small molecule and a polymer organic light emitting display device according to the material of the organic light emitting layer that generates light. The low molecular weight material is generally formed in a thin film form through vacuum deposition, and the high molecular material forms a thin film by using a solution coating method such as spin coating or inkjet printing.

Here, in the ink jet pinter method using a polymer material, the head of a line unit having a plurality of ink nozzles forms an organic light emitting layer by dropping a color liquid several times on the pixels of the color filter corresponding to the nozzle ink. do.

At this time, when the ink nozzle does not drop quickly in the process of dropping ink on a desired pixel, the color liquid is hardened at the input portion of the ink nozzle so that the color liquid is not transferred. In this case, there is a problem that the time is delayed in the process by dropping the color liquid to find again where the color liquid did not fall.

In addition, as the time for dropping the color liquid is delayed, the state of formation of the pixel currently being processed and the pixel previously processed is different, thereby decreasing the uniformity of light emission when the OLED is driven. In addition, since the color liquid is dropped between movements that are not stationary to match the tact time, there is a fear that the color may fall on the partition wall and adjacent subpixels. Accordingly, there is a problem that a defective product occurs due to the color liquid falling off at other than the selected pixel.

Accordingly, an aspect of the present invention is to provide an organic light emitting display device and a method of manufacturing the same for preventing defects caused by a printing method.

In order to achieve the above technical problem, a method of manufacturing an organic light emitting display device according to the present invention comprises the steps of forming an anode on a substrate; Forming a organic light emitting layer by transferring a color liquid onto the anode through the nozzle end in a state in which the face head having a plurality of nozzles is in contact with the substrate on which the anode is formed; It characterized in that it comprises a step of forming a cathode on the organic light emitting layer.

Specifically, the forming of the organic light emitting layer may include contacting the substrate with the color liquid suspended at the nozzle end by raising the face head toward the substrate.

The forming of the organic light emitting layer may include contacting the substrate with the color liquid suspended from the nozzle end by raising the substrate toward the surface head.

The method may further include forming a thin film transistor connected to the anode.

In order to achieve the above technical problem, an apparatus for manufacturing an organic light emitting display device according to the present invention includes a stage on which a substrate is mounted; And a surface head having a plurality of nozzles and transferring the color liquid to the substrate through the nozzle end in contact with the substrate.

The apparatus may further include an alignment mark and a vision system for aligning the stage and the face head.

In addition, at least one of the surface head and the stage is characterized in that used in the up / down / left / right direction.

Other technical problems and advantages of the present invention in addition to the above technical problem will be apparent from the description of the preferred embodiment of the present invention with reference to the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now become apparent with reference to FIGS. 1-4F.

1 is a cross-sectional view of an organic light emitting display device according to the present invention.

As shown in FIG. 1, the organic light emitting display device includes a thin film transistor formed on the substrate 20, an anode 36 connected to the thin film transistor and transmitting light, and a partition 38 exposing the anode 36. And an organic light emitting layer 40 for generating red (R), green (G), and blue (B) light, and a cathode 42 for reflecting light.

The thin film transistor supplies a driving signal for injecting holes into the anode 36. Such a thin film transistor includes a gate electrode 22 connected to a gate line, an active layer 26 formed on the gate insulating layer 24 covering the gate electrode 22, and an ohmic contact layer formed on both sides of the active layer 26 ( 32, a source electrode 28 formed on one side of the ohmic contact layer 32, and a drain electrode 30 formed on the other side of the ohmic contact layer 32.

The anode 36 is connected to the drain electrode 30 by a contact hole penetrating the passivation layer 34 and is supplied with a driving signal for injecting holes through the thin film transistor. The anode 36 transmits visible light generated from the organic light emitting layer 40 to the outside. The anode 36 uses indium tin oxide (ITO) or indium zinc oxide (IZO), which is a transparent conductive material, to transmit light.

The partition wall 38 is formed to have a hole exposing the anode 36 of each pixel region. The partition 38 is formed of an organic insulating material.

The organic light emitting layer 40 is formed to include a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer. The organic light emitting layer 40 is formed to implement red (R), green (G), and blue (B) colors for each subpixel through the face head 80 shown in FIG. 2 to be described later. The light emitting layer included in the organic light emitting layer 40 emits light according to the amount of current supplied to the anode 36 to emit light toward the substrate 20 via the anode 36.

The cathode 42 is formed on the substrate 20 on which the organic light emitting layer 40 is formed, and a driving signal for injecting electrons is supplied to the cathode 42. The cathode 42 reflects the light generated from the organic emission layer 40 toward the substrate 20 and emits the light to the outside. For this purpose, the cathode 42 uses a metal such as Al having high reflectivity or two or more alloys.

As such, when the driving signal is applied to each of the anode 36 and the cathode 42, electrons and holes are emitted, and the electrons and holes emitted from the anode 36 and the cathode 42 are organic light emitting layers. Recombination within 40 generates visible light. At this time, the visible light generated in the organic light emitting layer 40 is red (R), green (G), blue (B) color due to the color liquid of the polymer organic material formed on the organic light emitting layer 40 through the face head 80 It is possible to realize a prominent image and to make the image uniformity uniform.

Referring to FIG. 2, an apparatus for manufacturing an organic field display device includes a first surface including a nozzle 70 for transferring a color liquid and a nozzle 70 formed to form a red (R) color liquid and transferring onto the anode. The second surface head 80b having the head 80a and the nozzle 70 formed to form a green (G) color liquid and transferred onto the anode, and formed to form a blue (B) color liquid and formed on the anode A third surface head 80c having a nozzle 70 to be transferred to the substrate, an alignment mark 92 for aligning the correct position, a stage 94 having nozzles 70 to transfer the color liquid, and an alignment A vision system 90 is included that controls the face head 80 or stage 94 in accordance with the mark 92 to control the color liquid to contact the correct spot.

The first surface head 80a has a plurality of nozzles 70 transferring the red color liquid at a position corresponding to the subpixel SP having the red color. The second face head 80 has a plurality of nozzles 70 transferring the green (G) color liquid at a position corresponding to the subpixel SP having the green (G) color. The third surface head 80c has a plurality of nozzles 70 transferring the green (B) color liquid at a position corresponding to the subpixel SP having the green (G) color.

A plurality of nozzles 70 are formed on the first to third surface heads 80a, 80b, and 80c in contact with the substrate 20 seated on the stage 94, and red (R) and green ( G), the red (B) color liquid is transferred to the substrate 20. In this case, the color liquids R G and B are suspended in a predetermined amount at the ends of the nozzles 70 to form the organic light emitting layer 40 at a desired place.

On the stage 94, a substrate 20 having a display device for implementing an image is mounted. Accordingly, the stage 94 moves the substrate in the up / down / left / right directions through the control of the vision system 90. The alignment mark 92 is formed on the stage 94 and is used as a reference point for aligning the nozzles 70 of the first to third surface heads 80a, 80b, and 80c and the substrate 20. The vision system 90 is a device for measuring the accuracy of the alignment of the stage 94 and the face head 80.

Referring to FIG. 3, a nozzle 70 having red (R), green (G), and blue (B) sequentially in one face head 80 according to another embodiment of the manufacturing apparatus of the organic field display device according to the present invention. ).

The first to third surface heads 80a, 80b, and 80c and one surface head 80 may balance light emission uniformity through a fast process.

The nozzles 70 are formed on the first to third surface heads 80a, 80b, and 80c, and the red (R), green (G), and blue (b) color liquids are positioned on the subpixels corresponding to the color liquids. In contact, the color liquid is transferred to form the organic emission layer 40. Here, the nozzle 70 has an appropriate amount of inlet because the organic light emitting layer 40 must be formed in an appropriate amount at one time.

4A through 4E are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to the present invention.

Referring to FIG. 4A, a passivation layer 34 having a thin film transistor, a contact hole exposing a drain electrode of the thin film transistor, and an anode 36 connected to the thin film transistor through the contact hole are formed on the substrate 20.

Specifically, after the gate electrode 22 is formed on the substrate 20, the gate insulating film 24 is formed to cover the gate electrode 22, and the active layer 26 and the ohmic contact layer are formed on the gate insulating film 24. After the 32 is formed, the source and drain electrodes 28 and 30 facing each other with the channel region of the active layer 26 exposed by the ohmic contact layer 32 are formed to complete the thin film transistor.

Then, an inorganic insulating material or an organic insulating material is applied to cover the thin film transistor to form the protective film 34. The protective film 34 is patterned by a photolithography process and an etching process to form contact holes. The anode 36 is formed by applying a transparent conductive material to the entire surface on the substrate 20 on which the protective film 34 is formed, and then patterning the transparent conductive material by a photolithography process. Here, the anode 36 uses indium tin oxide (ITO) or indium zinc oxide (IZO), which is a transparent conductive material.

Referring to FIG. 4B, a partition wall 38 is formed on the substrate 20 on which the anode 36 is formed.

Specifically, the partition wall 38 is formed by depositing an organic insulating material on the protective film 34 on which the anode 36 is formed. The partition wall 38 is patterned by a photolithography process and an etching process using a mask to form holes for exposing the anode 36. The partition 38 is formed of an organic insulating material. Here, when the photosensitive organic insulating material is used, the partition 38 may form a hole only by a photolithography process. The partition wall 38 is surface-treated with a plasma containing fluorine on its entire surface to attract the color liquid formed on the face head 80 toward the anode 36.

Referring to FIG. 4C, the face head 80 corresponds to the substrate 20 with the color liquid suspended at the end of the nozzle 70.

Specifically, the surface head 80 including a substrate 20 on which the partition wall 38 is formed and a color liquid having red (R), green (G), and blue (B) formed while being suspended from the end of the nozzle 70. ) Corresponds.

Referring to FIG. 4D, the substrate 20 on which the anode 36 is formed contacts the nozzle 70 having red (R), green (G), and blue (B) color liquids.

Specifically, the substrate 20 having the anode 36 formed thereon is seated toward the surface head 80 on which the nozzle 70 is formed, which is a passage through which a plurality of red (R), green (G), and blue (B) color liquids are discharged. When the stage is raised, the surface head 80 and the substrate 20 come into contact with each other.

Alternatively, the surface head 80 is lowered toward the substrate 20 on which the anode 36 is formed so that the surface head 80 and the substrate 20 come into contact with each other.

Referring to FIG. 4E, organic light emitting layers 40a, 40b, and 40c having red (R), green (G), and blue (B) colors may be formed on the substrate 20 on which the anode 36 and the partition wall 38 are formed. Is formed.

Specifically, the red (R), green (G), and blue (B) color liquids of the face head 80 are in contact with the nozzle 70 of the face head 80 and the anode 36. Is transferred to the image. Thereafter, the stage 94 on which the substrate 20 is seated descends to the opposite side of the face head 80 or the face head 80 rises to the opposite side of the substrate 20 so that the nozzle 70 and the substrate 20 Are separated.

Referring to FIG. 4F, a cathode 42 is formed on the entire surface of the substrate 20 on which the organic emission layers 40a, 40b, and 40c are formed.

Specifically, the cathode 42 is formed by applying a material having a high reflectance on the organic light emitting layers 40a, 40b, and 40c. The cathode 42 uses a metal having high reflectance such as aluminum.

 On the other hand, the surface head 80 is an example of raising the substrate 20 in contact with each other in a state in which the color liquid is suspended from the end of the nozzle 70 to transfer the color liquid. 70) The organic light emitting layer 40 may be formed by raising the substrate 20 so as to contact the end and then discharging the color liquid from the end of the nozzle 70.

As described above, in the organic light emitting display device according to the present invention, the organic light emitting layer is formed by transferring the color liquid from the nozzle to the substrate while the surface head having the plurality of nozzles is in contact with the substrate.

As described above, the organic electroluminescent display device according to the present invention forms an organic light emitting layer by contacting the ink liquid suspended from the nozzle at a desired position. The curing time may be delayed to prevent the nozzle from clogging.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the description of the specification but should be defined by the claims.

Claims (7)

Forming an anode on the substrate; Forming a organic light emitting layer by transferring a color liquid suspended on a nozzle end in a state in which a face head having a plurality of nozzles is in contact with a substrate on which an anode is formed;  And forming a cathode on the organic light emitting layer. The method of claim 1, Forming the organic light emitting layer And raising the face head toward the substrate to contact the substrate with the color liquid suspended at the end of the nozzle. The method of claim 1, Forming the organic light emitting layer And raising the substrate toward the surface head so as to contact the substrate with the color liquid suspended at the end of the nozzle. The method of claim 1, A method of manufacturing an organic light emitting display device, the method comprising: forming a thin film transistor connected to the anode. A stage on which the substrate is mounted; And a surface head having a plurality of nozzles and transferring a surface of said color liquid to said substrate through said nozzle end in contact with said substrate. The method of claim 5, And an alignment mark and a vision system for aligning the stage and the face head. The method of claim 5, And at least one of the surface head and the stage is used in an up / down / left / right direction.

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