KR101338102B1 - Method of fabricating organic luminescence layer and organic electro luminescence display device - Google Patents

Abstract

The method of manufacturing an organic light emitting display device according to the present invention comprises the steps of forming a first electrode on the substrate, forming a hole transport layer on the electrode, an interlayer insulating layer having a larger width than the hole hydrogen layer on the hole transport layer; Forming an organic light emitting layer, and forming a second electrode on the organic light emitting layer.

Organic field, hole transport layer, hydrophobic, organic light emitting layer, electrode

Description

Organic light emitting layer formation method and organic light emitting display device manufacturing method {METHOD OF FABRICATING ORGANIC LUMINESCENCE LAYER AND ORGANIC ELECTRO LUMINESCENCE DISPLAY DEVICE}

1 is a cross-sectional view schematically showing a conventional organic light emitting display device.

2 is a plan view showing in detail the unit pixels of a conventional organic light emitting display device.

3 is a cross-sectional view showing a cross-section taken along line II ′ of FIG. 2.

4A to 4F are views illustrating a method of forming an organic light emitting layer according to an embodiment of the present invention.

5A to 5E are views illustrating a method of forming an organic light emitting layer according to another embodiment of the present invention.

DESCRIPTION OF THE REFERENCE SYMBOLS

112 substrate 116: electrode

118: organic light emitting layer 129: hole transport layer

142: hydrophobic pattern 143: interlayer insulating layer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an organic light emitting display device. In particular, an organic electroluminescent display device capable of preventing defects in hole transport layers and achieving high definition can be achieved by isolating R, G, and B organic light emitting layers. Luminescence Display Device).

Since the organic light emitting display device is a self-luminous type, the viewing angle is wider, the contrast is higher, and the visibility is superior to that of the liquid crystal display device. In addition, since the backlight is unnecessary, the device can be made thinner and lighter, and it is advantageous in terms of power consumption in comparison with LCDs which always need to illuminate the backlight in front of the display regardless of the display content since the current needs to be sent only to pixels requiring light emission. .

In addition, it has been in the spotlight as a next-generation display device because it has the advantage of enabling direct current low voltage driving, fast response speed, and easy moving picture display.

1 is a cross-sectional view schematically showing a configuration of a conventional organic light emitting display device.

As shown in the drawing, the organic light emitting display device 10 includes a thin film transistor array T on the transparent first substrate 12 and a first electrode 16 on the thin film transistor array T. ) And an organic light emitting layer 18 and a second electrode 19.

In this case, the organic light emitting layer 18 expresses red (R), green (G), and blue (B) colors. In general, a separate organic light emitting red and green blue color is generated for each pixel (P). The material is patterned and formed.

The first substrate 12 is bonded to the second substrate 28 having the hygroscopic agent 22 attached thereto through the seal 26, thereby completing the encapsulated organic light emitting display device 10. At this time, the moisture absorbent 22 is to remove moisture and oxygen that can penetrate into the capsule, and a portion of the substrate 28 is etched to fill the etched moisture absorbent 22 and fixed with a tape 25.

2 and 3 are enlarged views of the unit pixels of the thin film transistor array unit, FIG. 2 is a plan view, and FIG. 3 is a cross-sectional view taken along line II ′ of FIG. 2.

As illustrated in FIG. 2, the thin film transistor array unit includes a switching element Ts, a driving element Td, and a storage capacitor Cst for each of the plurality of pixels defined in the substrate 12. The switching element Ts or the driving element Td may be formed of a combination of one or more thin film transistors, respectively.

In addition, a gate line 32 arranged in one direction and a data line 34 intersecting each other with the gate line 32 and the insulating layer 57 ′ interposed therebetween are arranged on the substrate 12. A power supply line 35 is arranged to be spaced parallel to 34 and intersect the gate line 32.

The switching element Ts and the driving element Td include a thin film including gate electrodes 36 and 38, active layers 40 and 42, source electrodes 46 and 52, and drain electrodes 50 and 56. Transistors are used. In this case, the drain electrode 50 of the switching element Ts is connected to the gate electrode 38 of the driving element Td through the contact hole 54 and the source electrode 52 of the driving element Td. ) Is connected to the power line 35 through a contact hole 55. In addition, the drain electrode 56 of the driving device Td is connected to the first electrode 16 formed in the pixel portion P.

The storage capacitor Cst is formed by the power supply wiring 35, the polycrystalline silicon pattern 15, and an insulating layer 57 interposed therebetween.

As shown in FIG. 3, the driving device Td includes a gate electrode 38, an active layer 42, a source electrode 52, and a drain electrode 56, and is disposed on the driving device Td. The first electrode 16 in contact with the drain electrode 56 of the driving device Td with the insulating layer 57 therebetween, and the organic light emitting layer 18 generating light having a characteristic color on the first electrode 16. ) And an organic light emitting device 20 including the second electrode 19 formed on the organic light emitting layer 18.

In addition, charge transport layers are formed above and below the organic light emitting layer 18. The charge transport layer may be formed between the light emitting layer 18 and the electrodes 16 and 19. The charge transport layer may include an electron transport layer and a hole transport layer, and the charge transport layer may be a charge. The transport layer efficiently transports the carriers to the light emitting material, thereby increasing the probability of light emission coupling in the organic light emitting layer 18.

The organic light emitting display device includes a first electrode 16 and a second electrode 19 in the organic light emitting device 20 including the first electrode 16, the organic light emitting layer 18, and the second electrode 19. According to transparency, it is classified into a bottom emission type and a top emission type. In the case of the bottom emission type, the first electrode 16 is an anode made of a transparent conductive material having a high work function, such as indium tin oxide (ITO) or indium zinc oxide (IZO), and the second electrode 19 is a cathode having a low work function. to be. In this case, the charge transport layer 27 disposed between the organic light emitting layer 18 and the first electrode 16 is a hole transport layer and the charge transport layer 27 formed between the organic light emitting layer 18 and the second electrode 19. ) Is the electron transport layer. In the case of the top emission type, the electrode structure is different.

In the organic light emitting display device having the above structure, a separate organic light emitting layer 18 emitting red, green, and blue light for each pixel P is successively patterned, and electrons and holes are formed in the organic light emitting layer 18. The electron transport layer 27 and the hole transport layer 29 for transporting the light are also patterned separately for each pixel. However, since the hole transport layer 29 is made of a water-soluble material, when the hole transport layer 29 is successively patterned on red, green, and blue pixels by a general photolithography process, the hole transport layer 29 may be water-soluble. As a result, the water-soluble substance is mixed into the adjacent hole transport layer 29. Incorporation of such a water-soluble hole transport material has a problem causing a deterioration in image quality. In order to solve this problem, there is a problem that it is difficult to manufacture a high-definition organic electroluminescent display device when the adjacent hole transport layer 29 is spaced apart at regular intervals.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem. It aims to provide.

In order to achieve the above object, the organic light emitting layer forming method according to the present invention comprises the steps of providing a substrate, forming an electrode on the substrate, forming a hydrophobic pattern comprising a hydrophobic group on the substrate, Forming a hole transport layer between the hydrophobic patterns by applying a water-soluble hole transport material on the substrate, continuously laminating an insulating layer and an organic light emitting layer on the substrate, and etching the insulating layer and the organic light emitting layer to Forming an interlayer insulating layer having a larger width than the hole transport layer to cover the upper and side surfaces of the hole transport layer, and forming an organic light emitting layer on the interlayer insulating layer.

The etching of the insulating layer and the organic light emitting layer may include stacking photoresist on the insulating layer and the organic insulating layer, developing the photoresist to form a photoresist pattern having a larger width than the hole transport layer, and Etching the insulating layer and the organic light emitting layer in a larger width than the hole transport layer using a photoresist pattern.

In addition, the method of manufacturing an organic light emitting display device according to the present invention includes the steps of providing a substrate, forming a driving device on the substrate, providing a substrate, and forming a plurality of first electrodes on the substrate. Forming a hole transport layer on each of the first electrodes, and forming an interlayer insulating layer having a width greater than that of the hole hydrogen layer on the hole transport layer to separate the hole transport layer from the adjacent hole transport layer by covering the top and side surfaces thereof. Forming an organic light emitting layer on the interlayer insulating layer, and forming a second electrode on the organic light emitting layer.

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Hereinafter, an organic light emitting display device and a method of manufacturing the same according to the present invention will be described in detail with reference to the accompanying drawings.

4A to 4G illustrate a method of forming an organic light emitting layer of an organic light emitting display device according to an exemplary embodiment of the present invention. Subsequently, the organic light emitting layer is formed after forming a driving device including a gate electrode, an active layer, a source electrode, and a drain electrode on a substrate. However, in the following description, the step of forming the driving device is omitted for convenience of description. Only the method of forming the organic light emitting layer will be described.

First, as shown in FIG. 4A, an electrode 116 made of a transparent conductive material such as ITO or IZO is formed on the substrate 112, and then, as shown in FIG. 4B, a hydrophobic group such as trimethylsilyl group or fluorine group is included. A hydrophobic pattern 142 is formed on the electrode 116 by stacking a material. Subsequently, as shown in FIG. 4C, when the water-soluble hole transport material is stacked on the substrate 112 on which the hydrophobic pattern 142 is formed, the hole transport material is not formed on the hydrophobic pattern 142 but only between them. Thus, the hole transport layer 129 is formed. In this case, the three hole transport layers 129 illustrated in the drawing are hole transport layers formed in red, green, and blue pixels, respectively. Accordingly, each of the hole transport layers 129 may be formed in red, green, and blue pixels, respectively.

Thereafter, as illustrated in FIG. 4D, the insulating layer 143 and the organic light emitting layer 118a are sequentially stacked on the entire substrate 112 on which the hole transport layer 129 is formed. In this case, the organic light emitting layer 118a is an organic light emitting material emitting red light. Subsequently, as shown in FIG. 4E, after the photoresist is deposited on the organic light emitting layer 118a, the photoresist is developed using a mask to develop the hole transport layer 129 corresponding to the red pixel. The photoresist pattern 145 is formed on the top. In this case, since the width of the photoresist pattern 145 is greater than the width of the hole transport layer 129, the photoresist pattern 145 completely covers the hole transport layer 129.

Subsequently, as illustrated in FIG. 4F, the organic light emitting layer 118a and the insulating layer 143a are etched using the photoresist pattern 145, and the photoresist pattern 145 is removed to remove the hole transport layer ( The red organic light emitting layer 118 and the interlayer insulating layer 143 are formed on the layer 118. At this time, when the organic light emitting layer 118a and the insulating layer 143a are etched, the hole hydrogen layer 118 corresponding to the green and blue pixels is also etched and removed.

Since the width of the photoresist pattern 145 is formed to be wider than the width of the hole transport layer 118 so that the photoresist pattern 145 covers the hole transport layer 118, the interlayer etched by the photoresist pattern 145. The width of the insulating layer 143 is also larger than that of the hole transport layer 129 such that the interlayer insulating layer 143 completely covers the hole transport layer 129. In particular, the side surface of the hole transport layer 129 is also covered by the interlayer insulating layer 143.

Thereafter, the above process is repeated for the green and blue pixels, and the red, green, and blue organic light emitting layers 118R, 118G, and 18B, the interlayer insulating layer 143, and the hole transporting layer are disposed on the substrate 112. 129 is formed. When the green and blue organic light emitting layers 118G and 118B are formed, the hole transport layer 129 of another pixel, which is already formed, is covered by the interlayer insulating layer 129 and blocked from the outside, so that the hole transport of the pixel is performed. It is possible to prevent the material from being mixed into the hole transport layer 129 of the adjacent pixel. Therefore, it is possible to prevent a failure of the organic light emitting display device due to the failure of the hole transport layer 129.

In addition, in the organic light emitting display device manufactured by the above method, since the hole transport layer 129 is blocked by the interlayer insulating layer 143, even when the gap between adjacent pixels is minimized, the hole transport material of the adjacent pixels is prevented. It is possible to prevent mixing into the hole transport layer 129 of the pixel, thereby enabling a high-definition display element.

5A to 5E are views illustrating a method of manufacturing an organic light emitting display device according to another exemplary embodiment of the present invention.

As shown in FIG. 5A, an electrode 216 made of a transparent conductive material such as ITO or IZO and a hole transport material 229a are coated on the substrate 212, and then developed by applying a photoresist thereon. One photoresist pattern 245 is formed. Thereafter, as shown in FIG. 5B, the hole transport material 229a is etched using the first photoresist pattern to form a hole transport layer 229.

Thereafter, as shown in FIG. 5C, an insulating layer 243a and an organic light emitting layer 218a are stacked on the substrate 212, and a photoresist is stacked and developed on the second photoresist pattern 246. Form. In this case, the second resist pattern 246 is formed to have a width larger than the width of the hole transport layer 229.

Subsequently, as illustrated in FIG. 5D, the insulating layer 243a and the organic light emitting layer 218a are etched using the second resist pattern 246 to form the interlayer insulating layer 243 and the organic light emitting layer 218R. . In this case, since the interlayer insulating layer 243 and the organic light emitting layer 218R are formed to have a wider width than the hole transport layer 229, the interlayer insulating layer 243 completely blocks the hole transport layer 229. Therefore, as illustrated in FIG. 5E, when the organic light emitting layers 218G and 218B of the adjacent pixels are formed by repeating the above process, water-soluble hole transport materials are mixed into the adjacent hole transport layers 229, thereby causing defects. Can be prevented and high definition can be realized.

Meanwhile, the organic light emitting layers 218R, 218G, and 218B of the present invention are formed after forming the driving device shown in FIG. That is, by forming the driving element consisting of the gate electrode, the active layer, the source electrode and the drain electrode on the substrate by all the cut method, by forming the organic light emitting layer by the above-described method and forming the electron hydrogen layer and the cathode thereon It is to complete the organic light emitting display device.

As described above, in the present invention, the hole transport layer is blocked from the adjacent transport hole layers by the interlayer insulating layer, thereby preventing the incorporation of the hole transport material in the adjacent hole transport layers as well as minimizing the hole transport layers. Can be formed, and high definition can be realized.

Claims (13)

Providing a substrate; Forming an electrode on the substrate; Forming a hydrophobic pattern including a hydrophobic group on the substrate; Coating a water-soluble hole transport material on the substrate to form a hole transport layer between the hydrophobic patterns; Sequentially stacking an insulating layer and an organic light emitting layer on the substrate; And Forming an interlayer insulating layer having a width greater than that of the hole transport layer by etching the insulating layer and the organic light emitting layer to cover the top and side surfaces of the hole transport layer, and forming an organic light emitting layer on the interlayer insulating layer. . The method of claim 1, wherein etching the insulating layer and the organic light emitting layer comprises: Stacking a photoresist on the insulating layer and the organic insulating layer; Developing the photoresist to form a photoresist pattern having a width greater than that of the hole transport layer; And And etching the insulating layer and the organic light emitting layer in a width larger than that of the hole transport layer by using the photoresist pattern. The method of claim 1, wherein forming the hydrophobic pattern, forming the hole transport layer, laminating the organic light emitting layer, and etching the insulating layer and the organic light emitting layer are repeated to form a red, green, and blue organic light emitting layer. An organic light emitting layer forming method characterized in that. The method of claim 3, wherein the hole transport layer is covered by the interlayer insulating layer to block the incorporation of the hole transport material when forming the adjacent organic light emitting layer. Providing a substrate; Stacking an electrode and a hole transport material on the substrate; Etching the hole transport material to form a hole transport layer on the electrode; Sequentially stacking an insulating layer and an organic light emitting layer on the electrode on which the hole transport layer is formed; Forming an interlayer insulating layer having a width greater than that of the hole transport layer by etching the insulating layer and the organic light emitting layer to cover the top and side surfaces of the hole transport layer, and forming an organic light emitting layer on the interlayer insulating layer. . The method of claim 5, wherein the forming of the hole transport layer, Forming a first photoresist pattern on the hole transport material; And Forming a hole transport material by using the first photoresist pattern; The method of claim 5, wherein etching the insulating layer and the organic light emitting layer comprises: Stacking a photoresist on the insulating layer and the organic insulating layer; Developing the photoresist to form a second photoresist pattern having a width greater than that of the hole transport layer; And And etching the insulating layer and the organic light emitting layer in a width larger than that of the hole transport layer by using the second photoresist pattern. 6. The method of claim 5, wherein the red, green, and blue organic light emitting layers are formed by repeating the above steps. 10. The method of claim 8, wherein the hole transport layer is covered by the interlayer insulating layer to block the incorporation of the hole transport material when forming the adjacent organic light emitting layer. Providing a substrate; Forming a driving element on the substrate; Forming a plurality of first electrodes connected to a driving device on the substrate; Forming a hole transport layer on each first electrode; Forming an interlayer insulating layer having a larger width than the hole transport layer on the hole transport layer to separate the hole transport layer from the adjacent hole transport layer by covering the top and side surfaces thereof, and forming an organic light emitting layer on the interlayer insulating layer; And A method of manufacturing an organic light emitting display device, comprising: forming a second electrode on the organic light emitting layer. The method of claim 10, wherein the forming of the hole transport layer, Forming a hydrophobic pattern including a hydrophobic group on the substrate; And And forming a hole transport layer between the hydrophobic patterns by applying a water-soluble hole transport material on the substrate. The method of claim 10, wherein the forming of the hole transport layer, Applying a hole transport material and forming a photoresist pattern thereon; And And etching the coated hole transport material by using the photoresist pattern. The method of claim 10, wherein the forming of the interlayer insulating layer and the organic light emitting layer, Forming an insulating layer and an organic light emitting layer on the substrate; Stacking a photoresist on the insulating layer and the organic insulating layer; Developing the photoresist to form a photoresist pattern having a width greater than that of the hole transport layer; And And etching the insulating layer and the organic light emitting layer in a width greater than that of the hole transport layer by using the photoresist pattern.

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