KR100638146B1 - Masking apparatus and organic electro luminescence device and method for fabricating thereof using the same - Google Patents

Abstract

A mask device, an organic EL(Electro-Luminescence) display device, and a method for manufacturing the organic EL display device using the mask device are provided to increase a contrast ratio by blocking an external light through an opaque insulation layer. A mask is used for selectively masking a predetermined region on a substrate and includes a transparent region(140a) and a blocking region(140b). The transparent region passes light, while the blocking region blocks the light. An edge portion of the transparent region is expanded in a direction toward the blocking region. The edge portion of the transparent region is recessed in the direction toward the blocking region.

Description

Mask device and organic light emitting device using same and manufacturing method thereof {MASKING APPARATUS AND ORGANIC ELECTRO LUMINESCENCE DEVICE AND METHOD FOR FABRICATING THEREOF USING THE SAME}

1 is a perspective view schematically showing a conventional organic electroluminescent display device.

FIG. 2 is a cross-sectional view taken along line II ′ of the organic electroluminescent display device shown in FIG. 1. FIG.

3 is a diagram illustrating that incident external light is reflected by a cathode of an organic light emitting display device;

4 is a perspective view illustrating an organic electroluminescent display device according to an embodiment of the present invention.

FIG. 5 is a cross-sectional view taken along line II-II ′ of the organic electroluminescent display device shown in FIG. 4. FIG.

6 is a view showing the external light blocking function of the opaque insulating film of the present invention.

7 is a perspective view showing a state in which an opaque insulating film is formed on the present electrode.

8 is a view showing reduction of an opening area at an edge portion of a light emitting area.

9 is a view for explaining the exposure process of the opaque insulating material using the mask device and the same according to the present invention.

FIG. 10 is a view specifically showing a region C of the mask device shown in FIG. 9; FIG.

11A through 11E are steps of a manufacturing process of an organic light emitting display device according to an exemplary embodiment of the present invention.

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

2,102 substrate 4,104 anode electrode

8,108 bulkhead 109 dummy bulkhead

10,110: organic light emitting layer 12,112: cathode electrode

130: external light 140: mask device

6 insulating film 106 opaque insulating film

140a: transmission portion 140b: blocking portion

140c: depression

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to organic electroluminescent display devices, and more particularly, to an organic electroluminescent display device capable of improving contrast ratio and a method of manufacturing the same.

Recently, various flat panel displays have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes. Such flat panel displays include liquid crystal displays, field emission displays, plasma display panels, and electroluminescent displays. Etc.). In particular, the EL display device is basically formed by attaching electrodes to both sides of an organic light emitting layer including a hole transporting layer, a light emitting layer, and an electron transporting layer.

Such EL display elements are largely divided into inorganic EL display elements and organic EL display elements depending on the materials used. Among them, the organic EL display device can be driven at a lower voltage than the inorganic EL display device because when the charge is injected into the organic EL layer formed between the hole injection electrode and the electron injection electrode, electrons and holes are paired and extinguished to emit light. Has the advantage. In addition, the organic EL display device can be formed on a flexible transparent substrate, such as plastic, and can be driven at a voltage lower than 10V compared to a PDP or an inorganic EL display device, and the power consumption is relatively low. Small, excellent color

Fig. 1 is a perspective view showing a conventional organic EL display element, and Fig. 2 is a diagram showing a cut line II ′ of the organic EL display element shown in Fig. 1.

In the organic EL display device shown in FIG. 1, the first electrode (or anode electrode) 4 and the second electrode (or cathode electrode) 12 are formed on the substrate 2 in a direction crossing each other.

A plurality of anode electrodes 4 are spaced apart at predetermined intervals on the substrate 2. On the substrate 2 on which the anode electrode 4 is formed, an insulating film 6 having an opening for each EL cell E region is formed. On the insulating film 6, a partition 8 for separating the organic light emitting layer 10 and the cathode electrode 12 to be formed thereon is positioned. The partition wall 8 is formed in a direction crossing the anode electrode 4 and has a reverse taper structure in which the upper end portion has a wider width than the lower end portion. On the insulating film 6 on which the partition 8 is formed, the organic light emitting layer 10 and the cathode electrode 12 made of an organic compound are sequentially deposited on the entire surface. The organic light emitting layer 10 is formed by stacking a hole transporting layer, a light emitting layer, and an electron transporting layer on an insulating film. In the organic EL display device, electrons and holes are emitted when a driving signal is applied to the anode electrode 4 and the cathode electrode 12, and the electrons and holes emitted from the anode electrode 4 and the cathode electrode 12 are organic light emitting layers. Recombination within (10) generates visible light. At this time, the generated visible light comes out through the anode electrode 4 to display a predetermined image or image.

On the other hand, in the conventional organic EL display device, light incident from the outside almost completely passes through the anode electrode 4, the partition 8, and the organic light emitting layer 10. As a result, when no light is emitted from the organic light emitting layer 10, as shown in FIG. 3, the external light 30 incident from the surface of the substrate 2 is the anode electrode 4 and the organic light emitting layer, which are transparent conductive materials. In addition to being transmitted through (10), it is reflected by the cathode electrode 12, which is a metal electrode, and is emitted to the outside of the device. Accordingly, there is a problem that the contrast ratio is lowered.

Accordingly, it is an object of the present invention to provide an organic electroluminescent display device capable of blocking external light to improve contrast ratio.

Still another object of the present invention is to provide a mask device capable of preventing aperture ratio and luminance deterioration, an organic electroluminescent display device using the same, and a method of manufacturing the same.

In order to achieve the above object, the present invention provides a mask device for selectively masking a predetermined region on a substrate, the mask device comprising: a transmission portion for transmitting light; And a blocking unit for blocking light, wherein the edge region of the transmission unit is extended in the direction of the blocking unit.

The edge region of the transmissive portion is characterized in that it is extended in the form recessed in the direction of the blocking portion.

An organic electroluminescent display device according to the present invention comprises: an anode formed on a substrate; An opaque insulating layer which partially exposes the anode electrode to define a light emitting area and blocks external light including an opaque material; An organic light emitting layer formed in the light emitting region; And a cathode electrode intersecting the anode electrode with the organic light emitting layer interposed therebetween, wherein the light emitting region defined by the opaque insulating layer has a blocking portion, a transmitting portion, and a recessed portion recessed in the direction of the blocking portion in a corner region of the transmitting portion. Characterized in that formed using the device.

The opaque material is at least one of an opaque pigment and a resin.

A method of manufacturing an organic electroluminescent display device according to the present invention includes forming an opaque insulating material on a substrate on which an anode electrode is formed; Aligning a mask device on the opaque insulating material, the mask device having a shield, a transmissive portion and a recess embedded in the direction of the shield in the corner region of the transmissive portion; Exposing an opaque insulating material using the mask device; And developing the exposed opaque insulating material to partially expose the anode electrode to form an opaque insulating film defining a light emitting area.

The exposure area of the opaque insulating material may correspond to the transmissive part and the recessed part of the mask device.

The opaque insulating material is characterized in that it comprises at least one of an opaque resin and a pigment.

Forming a partition on the opaque insulating layer in a direction crossing the anode electrode; Forming an organic light emitting layer in the light emitting region; And forming a cathode electrode intersecting the anode electrode with the organic light emitting layer interposed therebetween.

Other objects and features of the present invention in addition to the above object will be apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 4 through 11E.

4 is a perspective view illustrating an organic EL display device according to an exemplary embodiment of the present invention, and FIG. 5 is a cross-sectional view taken along line II-II ′ of FIG. 4.

4 and 5, the organic EL display device illustrated in FIGS. 4 and 5 is formed to cross the anode electrode 104, the cathode electrode 112, and the anode electrode formed to cross each other with the organic light emitting layer 110 interposed therebetween on the substrate 102. In addition, an opaque insulating layer 106 and an opaque insulating layer 106 which define a light emitting area on the partition wall 108 and the anode electrode 104 formed in parallel with the cathode electrode 112 and block external light are provided.

A plurality of anode electrodes 104 are formed at a predetermined interval on the substrate 102 in a band shape. The partition 108 is formed in a direction crossing the anode electrode 4 and has an inverted taper structure in which the upper end portion has a wider width than the lower end portion. The organic light emitting layer 110 is formed by laminating a hole related layer including a hole injection layer and a hole transport layer, a light emitting layer for implementing color, and an electron related layer including an electron transport layer and an electron injection layer.

As illustrated in FIG. 6, the opaque insulating layer 106 partially exposes the anode electrode 104 to define the emission region P1.

In addition, the opaque insulating layer 106 includes an opaque material, and thus serves to improve the contrast ratio of the device by blocking and absorbing external light.

That is, in the present invention, since the insulating film is formed of an opaque material, the external light 130 that is directly incident on the opaque insulating film 106 among the external light 130 that is incident on the substrate 102 as shown in FIG. The light absorbed and extinguished by the 106 and reflected from the cathode electrode 112 is hardly emitted to the outside and is extinguished by the opaque insulating layer 106. As described above, the opaque insulating layer 106 insulates the anode electrode 104 and the cathode electrode 112 and blocks the traveling path of the external light 130, thereby improving the contrast ratio. Here, the opaque insulating material is prepared by adding an opaque resin and a pigment to the photosensitive insulating material.

On the other hand, such an opaque insulating film 106 is formed by a photolithography process by a photo mask apparatus. However, when the opaque insulating film 106 is formed by such a photolithography process, a problem arises in that an opening area having a width smaller than that of the light emitting area P1 designed in the photomask device is formed.

This will be described in more detail with reference to FIG. 8 showing the area A of FIG. 7 as follows.

That is, although the transmissive part of the mask device is designed to form a rectangular light emitting region P1 having a desired width, the edge region B of the rectangular light emitting region P1 is sufficiently formed due to the opaque insulating material. It will not be exposed. As a result, when the developing step is performed, the opaque insulating material in the corner region B of the light emitting region P1 that is not sufficiently exposed is not completely removed. Accordingly, as shown in FIG. 8, a portion of the opaque insulating material remains in the corner region B of the light emitting region P1, thereby forming an opening region P3 having a smaller width than the designed light emitting region P1. As described above, the light emission efficiency decreases as much as the reduced area of the light emission area P1, thereby causing a problem that the aperture ratio and the brightness decrease.

In order to prevent such a problem, the present invention proposes a mask device in which the shape of the permeable part is modified.

9 is a view showing a photomask device of the present invention and a step of forming the opaque insulating film 106 using the same.

The photo mask device 140 shown in FIG. 9 includes a transmissive portion 140a exposing a desired area and a blocking portion 140b excluding the transmissive portion 140a. Here, the transmission part 140a has a recessed part 140c recessed into the blocking part 140b area at its corner. The recess 140c of the transmission part substantially serves to expand the transmission area of the light. That is, when the exposure process using the mask device 140 is performed, not only the transmission part 140a but also the light may be transmitted through the depression part 140c, thereby sufficient for the edge of the light emitting area P1 having a relatively low light irradiation amount. Light can be irradiated. As a result, when the opaque insulating material 106a formed on the entire surface of the substrate 102 on which the anode electrode 104 is formed using the mask device 140 is exposed to the entire light emitting region P1 having a shape designed by a designer. Since the process can be performed, the opening area P3 having substantially the same width as the light emitting area P1 having the designed shape can be formed.

As a result, by providing the opaque insulating film 106, the contrast ratio can be improved and the aperture ratio and the brightness can be prevented from being lowered.

Hereinafter, a manufacturing method of a conventional organic EL display device will be described with reference to FIGS. 11A to 11E.

First, a metal transparent conductive material is deposited on a substrate 102 formed by using soda lime or hardened glass, and then patterned by a photolithography process and a dry etching process. 104 is formed. Herein, indium tin oxide or SnO ₂ may be used as the metal material.

After the opaque insulating material including at least one of an opaque pigment and a resin is formed on the photosensitive insulating material on the substrate 102 on which the anode electrode 104 is formed, as shown in FIGS. 9 and 10, the edge of the transmissive part 140a is formed. The exposure process is performed using the mask apparatus 140 in which the recessed part 140c was formed. Thereafter, the opaque insulating material is patterned by the developing process, thereby partially exposing the anode electrode 104 to form an opaque insulating layer 106 defining the emission region P1 as shown in FIG. 11B.

After the photosensitive organic material is deposited on the substrate 102 on which the opaque insulating film 106 is formed, the partition wall 108 is formed as shown in FIG. 11C by patterning by a photolithography process or the like. The partition 108 is formed to be non-overlapping with the light emitting region so as to intersect the plurality of anode electrodes 104 to distinguish the pixels.

The organic light emitting layer 110 is formed by depositing an organic material on the substrate 102 on which the barrier ribs 108 are formed using thermal deposition, vacuum deposition, or the like, as illustrated in FIG. 11D.

As the metal material is deposited on the substrate 102 on which the organic light emitting layer 110 is formed, as shown in FIG. 11E, the cathode electrode 112 is formed.

Meanwhile, the above-described mask device of the present invention and a method of manufacturing a thin film pattern using the same include not only forming a thin film pattern of an organic light emitting display device, but also thin film patterns included in a liquid crystal display (LCD), a plasma display panel (PDP), and a memory. It can be used as a photomask for forming.

As described above, the mask device, the organic light emitting display device using the same, and a method of manufacturing the same according to the present invention form an opaque insulating film using a mask device having a joining part that partially extends the transmission area. By forming an opaque insulating film using such a mask device, external light is blocked to improve contrast ratio and define a light emitting area having an accurate width, thereby preventing the aperture ratio and luminance from being lowered.

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

Claims (8)

A mask device for selectively masking a predetermined region on a substrate, the mask device comprising: The mask device is A transmission portion for transmitting light; It has a blocking unit for blocking light, The edge area of the transmissive portion is a mask device, characterized in that extending in the direction of the blocking portion. The method of claim 1, The edge area of the transmissive portion is a mask device, characterized in that extending in the form recessed in the direction of the blocking portion. An anode electrode formed on the substrate; An opaque insulating layer which partially exposes the anode electrode to define a light emitting area and blocks external light including an opaque material; An organic light emitting layer formed in the light emitting region; A cathode electrode intersecting the anode electrode with the organic light emitting layer interposed therebetween, The light emitting region defined by the opaque insulating film is An organic electroluminescent display device, comprising: a mask device having a shielding portion, a transmitting portion, and a recessed portion recessed in a direction of the blocking portion in a corner region of the transmitting portion. The method of claim 3, wherein The opaque material is an organic electroluminescent display device, characterized in that at least one of an opaque pigment and a resin. Forming an opaque insulating material on the substrate on which the anode electrode is formed; Aligning a mask device on the opaque insulating material, the mask device having a shield, a transmissive portion and a recess embedded in the direction of the shield in the corner region of the transmissive portion; Exposing an opaque insulating material using the mask device; And developing the exposed opaque insulating material to partially expose the anode electrode to form an opaque insulating film defining a light emitting area. The method of claim 5, And an exposure area of the opaque insulating material corresponds to the transmissive part and the recessed part of the mask device. The method of claim 5, The opaque insulating material includes at least one of an opaque resin and a pigment. The method of claim 5, Forming a partition on the opaque insulating layer in a direction crossing the anode electrode; Forming an organic light emitting layer in the light emitting region; And forming a cathode electrode intersecting the anode electrode with the organic light emitting layer interposed therebetween.

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