KR20050059811A - Electroluminescent display device and method of fabricating the same - Google Patents

Abstract

The organic light emitting display device according to the present invention comprises: first and second substrates facing each other and spaced apart from each other; A driving thin film transistor formed on an inner surface of the first substrate; A connection electrode connected to the driving thin film transistor and made of a conductive material having a first hardness; A first electrode formed on the entire inner surface of the second substrate; An organic light emitting layer formed under the first electrode; And a second electrode formed under the organic light emitting layer and made of a conductive material in contact with the connection electrode and having a second hardness different from the first hardness.

Description

Organic electroluminescent device and manufacturing method thereof {Electroluminescent Display Device and Method of Fabricating the same}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electroluminescent device (OELD), and more particularly, to a dual panel type organic electroluminescent device for forming an array layer including a thin film transistor and an organic electroluminescent layer on different substrates, and a method of manufacturing the same. will be.

One of the new flat panel displays, the organic light emitting display device is self-luminous and thus has a better viewing angle and contrast ratio than the liquid crystal display device. In addition, since it is possible to drive DC low voltage, fast response speed, and all solid, it is strong against external shock, wide use temperature range, and especially inexpensive in terms of manufacturing cost. Such an organic light emitting diode is also referred to as an organic light emitting diode (OLED).

In particular, since the organic light emitting device has a very simple process unlike a liquid crystal display device or a plasma display panel (PDP), deposition and encapsulation equipment are all.

In particular, in the active matrix method, a voltage controlling a current applied to a pixel is charged in a storage capacitor (C _ST ), and the gate is applied by applying a voltage until the next frame signal is applied. Drive continuously for one screen regardless of the number of wires.

Therefore, in the active matrix system, since the same luminance is displayed even when a low current is applied, low power consumption, high definition, and large size can be obtained.

Hereinafter, the basic structure and operation characteristics of the active matrix organic light emitting display device will be described in detail with reference to the accompanying drawings.

1 is a circuit diagram showing the configuration of one pixel region of a general active matrix organic light emitting display device.

As shown, a scan line is formed in a first direction, a signal line and a power line are formed in a second direction crossing the first direction and spaced apart from each other by a predetermined distance. In this example, one pixel region is defined.

The scanning line and the intersection of the signal line has the addressing element switching thin film transistor (addressing element); and is formed with a (T _S Switching TFT), it is connected to the switching thin film transistor (T _S) of storage capacitor (C _ST) is formed And a driving thin film transistor T _D , which is a current source element, is connected to a connection portion and a power line of the switching thin film transistor T _S and the storage capacitor C _ST to form the driving thin film transistor T A first electrode is connected to T _D ), and the first electrode is connected to the second electrode through an electroluminescent diode (D _EL ) of a constant current driving method.

The switching thin film transistor T _S controls the gate voltage of the driving thin film transistor T _D , and the storage capacitor C _ST stores a voltage applied to the driving thin film transistor T _D.

Hereinafter, the driving principle of the active matrix organic light emitting display device will be described.

In the active matrix method, when the gate signal is applied to the gate of the selected switching thin film transistor, the switching thin film transistor is turned on, and the data signal passes through the switching thin film transistor to be applied to the driving thin film transistor and the storage capacitor. When the transistor is turned on, current from the power supply line is applied to the organic light emitting layer through the gate of the driving thin film transistor to emit light.

At this time, the degree of opening and closing of the driving thin film transistor is changed according to the magnitude of the data signal, so that gray scale display can be performed by adjusting the amount of current flowing through the driving thin film transistor.

In the non-selection period, the data signal charged in the storage capacitor is continuously applied to the driving thin film transistor, so that the organic light emitting diode can emit light continuously until the next screen signal is applied.

FIG. 2 is a plan view of one pixel area of a conventional active matrix type organic light emitting display device, and an example of a two TFT structure having one switching thin film transistor and one driving thin film transistor will be described.

As shown in the drawing, the gate wiring 37 is formed in the first direction, intersects with the gate wiring 37, and the data wiring 51 and the power line 41 are formed to be spaced apart from each other, and the gate wiring 37 is formed. ), The pixel region P is defined by an area where the data line 51 and the power line 41 cross each other.

The switching thin film transistor T _S is positioned in an area where the gate wiring 37 and the data wiring 51 cross each other, and the driving thin film transistor T _D is located at a point where the switching thin film transistor T _S and the power line 41 cross each other. ) And the capacitor electrode 34 forming an integrated pattern with the semiconductor layer 31 of the switching thin film transistor T _S overlaps the power line 41 to form the storage capacitor C _ST .

In addition, the first electrode 58 is formed in connection with the driving thin film transistor T _D , and although not shown in the drawing, the organic light emitting layer and the second electrode are sequentially formed in the region covering the first electrode 58. Formed to form an organic light emitting diode (D _EL ).

The driving thin film transistor T _D includes a driving semiconductor layer 32 and a driving gate electrode 38, and the switching thin film transistor T _S includes a switching semiconductor layer 31 and a switching gate electrode 35.

Hereinafter, the stacked structure of the organic light emitting diode, the driving thin film transistor, and the storage capacitor will be described in detail with reference to the accompanying drawings.

FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 2.

As illustrated, a driving thin film transistor T _D including the semiconductor layer 32, the gate electrode 38, the source and the drain electrodes 50 and 52 is formed on the substrate 1, and the source electrode A power electrode 42, which is a part of the power line 41 of FIG. 2, is connected to the power supply line 50, and a first electrode 58 made of a transparent conductive material is connected to the drain electrode 52.

A capacitor electrode 34 made of the same material as that of the semiconductor layer 32 is formed in a lower portion corresponding to the power electrode 42, so that the power electrode 42 and the capacitor electrode 34 overlap each other. The area constitutes a storage capacitor C _ST .

In addition, an organic light emitting layer 64 and a second electrode 66 made of an opaque metal material are sequentially stacked on the first electrode 58 to form an organic light emitting diode D _EL .

Looking at the stack structure of the insulating layers around the lower portion of the organic light emitting diode (D _EL ), the buffer layer 30 to buffer between the substrate 1 and the semiconductor layer 32 and the storage capacitor C _ST. ), A first insulating layer 40 used as an insulator, a second insulating layer 44 between the drain electrode 52 and the power electrode 42, and the first electrode 58 and the drain electrode 52. ) And a third insulating layer 54 between the first insulating layer 54 and the fourth insulating layer 60 between the first electrode 58 and the organic light emitting layer 64 are sequentially stacked. The insulating layers 40, 44, 54, and 60 each include contact holes (not shown) for electrical connection between the respective layers.

Hereinafter, FIGS. 4A to 4I are cross-sectional views illustrating cross-sectional views cut along the cutting line III-III of FIG. 2, respectively, according to manufacturing process steps. FIG. 4A to 4I illustrate exposure and development using a photo-resist (PR) photosensitive material. It proceeds by the process of patterning by photolithography which includes the process), and this series of patterning processes is demonstrated in order below.

In FIG. 4A, the buffer layer 30 is formed on the insulating substrate 1 using the first insulating material over the entire surface of the substrate, and the active layer 32a is formed by using polysilicon on the buffer layer 30. ) And capacitor electrode 34.

Next, in FIG. 4B, a second insulating material and a first metal are successively deposited and patterned on the substrate having passed through FIG. 4A to form a gate insulating film 36 and a gate on the active layer 32a, respectively. Electrode 38 is formed.

In FIG. 4C, a first insulating layer 40 made of a third insulating material is formed on the substrate having passed through FIG. 4B, and a second metal is deposited and patterned on the first insulating layer 40. The power electrode 42 is formed in the position which covers the capacitor electrode 34.

In FIG. 4D, a first insulating material is deposited on the substrate having passed through the step of FIG. 4C, and then patterned to expose both ends of the active layer 32a and a part of the power electrode 42, respectively. The second insulating layer 44 having the contact holes 46a and 46b and the third contact hole 48 is formed.

In this step, the exposed both ends of the active layer 32a are ion-doped, and the ion-doped portion is formed into an ohmic contact layer 32b containing impurities to form an ohmic contact region 32b. The semiconductor layer 32 which consists of the active layer 32a containing the () is completed.

Next, in FIG. 4E, the third metal is deposited and patterned to form a power electrode 42 and an ohmic contact region through the third contact hole 48 of FIG. 4D and the first contact hole 46a of FIG. 4D. A source electrode 50 connected to the source electrode 50 and a drain electrode 52 spaced apart from the source electrode 50 at a predetermined interval and connected to the ohmic contact layer 32b through the second contact hole 46b of FIG. 4D. ).

In this step, the driving thin film transistor T _D including the semiconductor layer 32, the gate electrode 38, the source and drain electrodes 50 and 52 is completed.

The power electrode 42 and the capacitor electrode 34 are electrically connected to the source electrode 52 and the semiconductor layer of the switching thin film transistor (not shown), respectively, and the first insulating layer 40 is used as an insulator. The storage capacitor C _ST is formed.

In FIG. 4F, a fourth insulating material is deposited and patterned on the substrate having passed through FIG. 4E to form a third insulating layer 54 having a fourth contact hole 56.

Next, in FIG. 4G, the first electrode is connected to the drain electrode 50 through the fourth contact hole (56 in FIG. 4F) by depositing and patterning a fourth metal on the substrate having passed through FIG. 4F. Form 58.

In FIG. 4H, a fourth insulating layer 60 having an opening 62 exposing the first electrode 58 is formed by depositing and patterning a fifth insulating material on the substrate having undergone the step 4g.

The fourth insulating layer 60 serves to protect the driving thin film transistor T _D from moisture and foreign matter.

In FIG. 4I, an organic electroluminescent layer 64 connected to the first electrode 58 through the opening 62 (in FIG. 4H), and a second electrode using a fifth metal on the organic electroluminescent layer 64. 66 is formed over the entire surface of the substrate.

Hereinafter, a laminated structure of a conventional organic light emitting diode panel will be described in detail with reference to the accompanying drawings.

FIG. 5 is a cross-sectional view of a conventional organic light emitting diode, and illustrates an encapsulation structure centering on a connection portion between an organic light emitting diode and a driving thin film transistor.

As shown in the drawing, the first and second substrates 70 and 90 are disposed to be spaced apart from each other by a subpixel unit, which is the minimum unit for implementing a screen, and the sub-pixel unit is disposed on an inner surface of the first substrate 70. a plurality of driving thin film transistors formed (T _D) for containing the array and the element layer 80 is formed, the array element layer 80, an upper portion the driving thin film transistor (T _D) is connected to the first electrode (72 in sub-pixels, ) Is formed, and an organic light emitting layer 74 emitting red, green, and blue colors in subpixel units is formed on the first electrode 72, and a second electrode is formed on the entire upper surface of the organic light emitting layer 74. 76 is formed.

The organic light emitting layer 74 interposed between the first and second electrodes 72 and 76 and the first and second electrodes 72 and 76 forms an organic light emitting diode D _EL and the organic light emitting layer 74. The light emitted from the light emitting device is characterized in that the bottom emission method is emitted toward the first electrode (72).

The second substrate 90 is used as an encapsulation substrate, and a recess 92 is formed at an inner central portion of the second substrate 90, and moisture from the outside is formed in the recess 92. A moisture absorbent 94 is sealed to block absorption and protect the organic light emitting diode D _EL .

The inner surface of the second substrate 90 in which the moisture absorbent 94 is sealed and the second electrode 76 are positioned to be spaced apart from each other by a predetermined distance.

The edges of the first and second substrates 70 and 90 are encapsulated by the seal pattern 85.

As described above, the conventional bottom emission type organic light emitting diode device is manufactured by bonding an array device and a substrate on which an organic light emitting diode is formed and a separate substrate for encapsulation. In this case, since the product of the yield of the array device and the yield of the organic light emitting diode determines the yield of the organic light emitting diode, the overall organic process of the organic light emitting diode structure yields the overall process yield by the organic electroluminescent diode process. There was a problem that is greatly limited. For example, even if the array element is well formed, if a defect occurs due to foreign matter or other factors in forming the organic light emitting layer using a thin film of about 1,000 GPa, the organic light emitting element is judged to be a poor grade. .

This results in a loss of overall costs and material costs that were required to manufacture the array device of good quality, there was a problem that the production yield is lowered.

In addition, the bottom emission method has a high degree of freedom and stability due to the encapsulation process, and has a problem in that it is difficult to be applied to a high resolution product due to the limitation of the aperture ratio, and the top emission method is easy to design a thin film transistor and improves the aperture ratio. It is advantageous in terms of product life, but in the conventional top emission type structure, since the material selection range is narrow as the cathode is normally positioned on the organic light emitting layer, the transmittance is limited and the light efficiency is reduced, and the light transmittance is minimized. In order to configure a thin film type protective film, there was a problem in that it does not sufficiently block outside air.

In order to solve the above problems, the present invention is to provide a high-resolution / high aperture structure active matrix organic light emitting display device with improved production yield.

To this end, an object of the present invention is to form an array element and an organic light emitting diode on a different substrate, and to connect the driving thin film transistor of the array element and the second electrode of the organic light emitting diode through a separate electrical connection pattern The present invention provides a panel type organic light emitting display device and a method of manufacturing the same.

It is still another object of the present invention to provide a dual panel type organic light emitting diode that forms an array element and an organic light emitting diode on different substrates, wherein the second electrode of the organic light emitting diode is connected to a driving thin film transistor of the array element. Provides a dual panel type organic light emitting display device and a method of manufacturing the same, in which a separate connection electrode is formed of a material having different hardness or mechanical strength, thereby improving contact characteristics between the second electrode and the electrical connection pattern. It is.

In order to achieve the above object, the present invention and the first and second substrate facing each other and spaced apart; A driving thin film transistor formed on an inner surface of the first substrate; A connection electrode connected to the driving thin film transistor and made of a conductive material having a first hardness; A first electrode formed on the entire inner surface of the second substrate; An organic light emitting layer formed under the first electrode; An organic light emitting display device includes a second electrode formed under the organic light emitting layer, the second electrode made of a conductive material having contact with the connection electrode and having a second hardness different from the first hardness.

The first hardness may be greater than the second hardness, and serrated irregularities may be formed on the top surface of the connection electrode.

The lower portion of the connection electrode may further include a connection pattern formed of an insulating material having a height corresponding to the separation distance between the first and second substrates, and the driving thin film transistor may include a gate electrode, an active layer, a source electrode, and a drain. An electrode.

The organic light emitting display device of the present invention comprises: a gate wiring formed on the first substrate; A data line crossing the gate line; A power line parallel to the data line and spaced at a predetermined interval; The semiconductor device may further include a switching thin film transistor connected to the gate wiring, the data wiring, and the driving thin film transistor.

On the other hand, the present invention comprises the steps of forming a driving thin film transistor on the first substrate; Forming a connection electrode connected to the driving thin film transistor and made of a conductive material having a first hardness; Forming a first electrode on the second substrate; Forming an organic light emitting layer on the first electrode; Forming a second electrode on the organic light emitting layer, the second electrode including a conductive material having a second hardness different from the first hardness; It provides a method of manufacturing an organic light emitting display device comprising the step of bonding the first and second substrates in contact with the connection electrode and the second electrode.

The first hardness may be greater than the second hardness, and may further include forming serrated irregularities on the top surface of the connection electrode.

The method may further include forming a connection pattern made of an insulating material under the connection electrode.

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

FIG. 6 is a cross-sectional view of an organic light emitting display device according to an embodiment of the present invention, and is schematically illustrated based on an electrical connection structure.

As shown, the first and second substrates 110 and 150 in which a plurality of subpixels are defined are arranged to face each other with a predetermined interval therebetween.

An array element layer 140 including a plurality of driving thin film transistors T _D formed in subpixel units is formed on an inner surface of the first substrate 110, and a driving thin film transistor is formed on the array element layer 140. A connecting electrode 144 is formed in contact with the T _D.

The driving thin film transistor T _D may include a gate electrode 112, an active layer 114, a source electrode 116, and a drain electrode 118. Subsequently, the aforementioned connection electrode 144 may include a drain electrode 118. ).

The connection electrode 144 is made of a conductive material and must be electrically connected to the second electrode 162 on the second substrate 150 to fill the space between the spaced apart first and second substrates 110 and 150. It must have a height. To this end, a connection pattern 142 made of an insulating material is formed under the connection electrode 144. Although not illustrated, in another embodiment, the connection pattern 142 may be formed in multiple layers, and the connection electrode 144 may be connected to the driving thin film transistor T _D through a separate conductive layer.

In addition, a first electrode 152 is formed on the entire inner surface of the second substrate 150, and red, green, and blue sub-emitting layers 156a, 156b, which are repeatedly arranged in subpixel units, below the first electrode 152. An organic light emitting layer 160 including 156c is formed, and a second electrode 162 is formed in the subpixel unit below the organic light emitting layer 160.

In more detail, the organic light emitting layer 160 is formed on the lower surface of the first carrier transfer layer 154 and the first carrier transfer layer 154 formed on the lower surface of the first electrode 152. And a light emitting layer 156 including green and blue sub light emitting layers 156a, 156b, and 156c, and a second carrier transfer layer 158 formed under the light emitting layer 156 and in contact with the top surface of the second electrode 162. Include.

For example, when the first electrode 152 corresponds to an anode and the second electrode 162 corresponds to a cathode, the first carrier transport layer 154 sequentially corresponds to the hole injection layer and the hole transport layer, and the second carrier The transport layer 158 in turn corresponds to the electron transport layer and the electron injection layer.

In addition, the organic light emitting layer 160 interposed between the first and second electrodes 152 and 162 and the first and second electrodes 152 and 162 corresponds to an organic light emitting diode D _EL .

The seal patterns 170 are positioned at edges of the first and second substrates 110 and 150 to bond the first and second substrates 110 and 150 to each other.

In the organic light emitting diode according to the embodiment of the present invention, the organic light emitting diode (D _EL ) and the array element layer 140 are formed on different substrates, and the top surface of the connection electrode 144 has a second electrode ( 162) It is a dual-panel type that is connected to the bottom surface so that the current supplied from the driving thin film transistor (T _D ) is transmitted to the second electrode 162 of the organic light emitting diode (D _EL ) through the connecting electrode 144. It features.

In this case, the connection electrode 144 and the second electrode 162 may be formed of materials having different hardness or mechanical strength. That is, the first firmness of the connection electrode and the second firmness of the second electrode have different values.

The connection electrode 144 and the second electrode 162 are formed on the first and second substrates 110 and 150, respectively, and then mechanically contact with each other by bonding. The uppermost area of the connection electrode 144 is narrow and is bonded. There is also a possibility of desorption, so there is a possibility that a defect occurs. In order to solve this problem, when the connecting electrode 144 and the second electrode 162 are formed of a material having a different hardness, the contact surface made of a material having a large hardness when bonding into a contact surface made of a material having a small hardness Particularly, the contact characteristics of the connection electrode 144 and the second electrode 162 are improved.

In addition, since the organic light emitting device according to the present invention is an upper light emitting method, it is easy to design a thin film transistor, and has the advantage that high aperture ratio / high resolution can be realized.

The contact between the connection electrode 144 and the second electrode 162 in the organic light emitting diode according to the embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 7 is an enlarged view of A of FIG. 6, and shows a contact portion between a connection electrode and a second electrode of an organic light emitting display device according to an embodiment of the present invention.

As illustrated in FIG. 7, a first insulating layer 113 used as a gate insulating film of the driving thin film transistor T _D is formed on the first substrate 110, and an upper portion of the first insulating layer 113 is formed. A second insulating layer 120 used as a protective film covering the driving thin film transistor T _D is formed.

A connection pattern 142 made of an insulating material is formed on the second insulating layer 120, and a connection electrode 144 made of a conductive material is formed on the connection pattern 142. For example, the connection pattern 142 may be formed of a photosensitive organic material.

Meanwhile, a first electrode 152 is formed on an inner surface of the second substrate facing the first substrate 110 and spaced apart from each other, and a first carrier transfer layer 154 and a light emitting layer below the second electrode 152. 156 and an organic light emitting layer 160 including the second carrier transport layer 158 are formed. A second electrode 162 made of a conductive material is formed under the organic light emitting layer 160.

The connection electrode 144 is made of a conductive material having a first hardness, and the second electrode 162 is made of a conductive material having a second hardness different from the first hardness.

For example, the first firmness may be greater than the second firmness. At this time, when the top surface of the connection electrode 144 naturally has micro unevenness, the connection electrode 144 and the second electrode 162 may be formed by the bonding of the first and second substrates 110 and 150. When contacted and pressure is applied, the protrusion of the uppermost surface of the connecting electrode 144 is connected to the lowermost surface of the second electrode 162. Therefore, even when the first and second substrates 110 and 150 are inclined and bonded to each other, the connection electrode 144 and the second electrode 162 may be contacted more stably.

In order to maximize this effect, a tooth-shaped unevenness may be artificially formed on the uppermost surface of the connection electrode 144 than naturally occurring fine irregularities.

Although the rigidity of the connection electrode 144 is illustrated in the present embodiment, the case where the rigidity of the second electrode 162 is large may be applied, and in this case, the artificial artificial irregularities of the tooth shape are applied to the second electrode 162. It is formed at the bottom of the to maximize the effect of improving its contact characteristics.

A method of manufacturing an organic light emitting display device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

8A to 8F are cross-sectional views illustrating a manufacturing process of a first substrate of an organic light emitting display device according to an embodiment of the present invention, and FIGS. 9A to 9C illustrate a second substrate of an organic light emitting display device according to an embodiment of the present invention. It is sectional drawing which shows a process.

8A illustrates a step in which the gate electrode 112 is formed on the first substrate 110. Although not shown in the drawings, a gate line connected to the gate electrode 112 and a power line parallel to the gate line and spaced apart from each other are formed in this step.

8B illustrates forming the first insulating layer 113, the active layer 114, and the ohmic contact layer 114a on the gate electrode 112. The first insulating layer is formed on the entire surface of the first substrate 110 on the gate electrode 112 and used as the gate insulating film. An active layer 114 made of pure semiconductor material and an ohmic contact layer 114a made of impurity semiconductor material are continuously formed on the first insulating layer 113 corresponding to the gate electrode 112.

8C illustrates forming source and drain electrodes 116 and 118 on the ohmic contact layer 114a. The source and drain electrodes 116 and 118 are formed spaced apart from each other on the ohmic contact layer 114a, and the active layer 114 is removed by removing the ohmic contact layer 114a between the source and drain electrodes 116 and 118. ) Is exposed.

The gate electrode 112, the active layer 114, the source electrode 116, and the drain electrode 118 form a driving thin film transistor T _D.

8D is a step of forming a second insulating layer 120 on the driving thin film transistor T _D. A drain contact hole 120a exposing a part of the drain electrode 118 is formed in the second insulating layer 120.

8E is a step of forming a connection pattern 142 on the second insulating layer 120. The connection pattern 142 may be made of the same insulating material as that of the first insulating layer 113 or the second insulating layer 120, or may be made of a photosensitive organic material. In addition, it may be formed as a single layer or multiple layers, and when bonded together, the driving thin film transistor T _D of the first substrate 110 and the organic light emitting diode D _{EL of} the second substrate 150 in FIG. All you need to do is to make the connection as high as possible.

8F is a step of forming the connection electrode 144 on the connection pattern 142. The connection electrode 144 is made of a conductive material and is connected to the drain electrode 118 of the driving thin film transistor T _D through the drain contact hole 120a of FIG. 8D.

Here, the connecting electrode 144 has a first hardness, which has a different value from the second hardness of the second electrode (162 of FIG. 7) formed on the second substrate (150 of FIG. 7). . For example, the connection electrode 144 may be formed such that the first firmness has a larger value than the second firmness.

In addition, jagged artificial irregularities may be formed on the top surface of the connection electrode 144 on the connection pattern 142, or naturally occurring fine irregularities may be formed. The unevenness may be formed to further improve contact between the connection electrode 144 and the second electrode 162 of FIG. 7, for example, using an etching gas for the connection electrode 144. It may be formed by dry etching to a degree that does not impair the function of 144.

9A is a step of forming the first electrode 152 on the second substrate 150. The first electrode 152 is formed on the entire surface of the substrate and used as a common electrode.

9B is a step of forming an organic light emitting layer 160 on the first electrode 152. The organic light emitting layer 160 is formed on the first carrier transfer layer 154 formed on the first electrode 152, the emission layer 156 formed on the first carrier transfer layer 154, and the emission layer 156. The second carrier transfer layer 158 is formed, and the emission layer 156 includes red, green, and blue sub-emitting layers 156a, 156b, and 156c that are alternately formed for each subpixel.

9C illustrates forming the second electrode 162 on the organic light emitting layer 160. The second electrode 162 may be made of a conductive material having a second hardness different from that of the first electrode of the connection electrode 144. For example, the second electrode 162 may have a smaller value than the first hardness.

Meanwhile, the organic light emitting layer 160 interposed between the first and second electrodes 152 and 162 and the first and second electrodes 152 and 162 forms an organic light emitting diode D _EL .

Although not shown in the drawings, the seal pattern 170 is formed at an edge portion between the first substrate 110 manufactured through the processes of FIGS. 8A to 8F and the second substrate 150 manufactured through the processes of FIGS. 9A to 9C. After forming, the first and second substrates 110 and 150 are bonded together to complete the organic light emitting display device.

When the connecting electrode 144 and the second electrode 162 are contacted by the bonding of the first and second substrates 110 and 150 and pressure is applied, the unevenness of the top surface of the connecting electrode 144 is dug into the second electrode 162. The connection electrode 144 and the second electrode 162 are connected. Therefore, even when the first and second substrates 110 and 150 are inclined and bonded to each other, the connection electrode 144 and the second electrode 162 are in contact with each other more stably so that the connection electrode 144 and the second electrode 162 are in contact with each other. ), The contact properties of

The organic light emitting display device and the method of manufacturing the same according to the present invention are not limited to the above embodiments, and various changes and modifications are made by those skilled in the art to which the present invention pertains without departing from the spirit of the present invention. It is evident that this is possible, and it is apparent from the appended claims that these changes and variations fall within the invention.

As described above, according to the organic light emitting device and the manufacturing method thereof according to the present invention, first, since the array element and the organic light emitting diode is formed on a different substrate, it is possible to improve the production yield and production management efficiency, the product Second, it is possible to extend the lifespan, and secondly, because it is a top emission type, it is easy to design thin film transistor and realize high opening ratio / high resolution. Third, the connecting electrode contacting the driving thin film transistor and the second electrode of the organic light emitting diode are different from each other. It is advantageous to form a conductive material having a hardening property to improve contact characteristics between the connecting electrode and the second electrode.

1 is a circuit diagram showing the configuration of one pixel region of a general active matrix organic electroluminescent device.

2 is a plan view of one pixel area of a conventional active matrix type organic light emitting display device.

FIG. 3 is a cross-sectional view taken along the line III-III of FIG. 2. FIG.

4A to 4I are cross-sectional views each showing a cross section cut along the cutting line III-III of FIG.

5 is an overall cross-sectional view of a conventional organic light emitting display device.

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

7 is an enlarged view of A of FIG. 6.

8A to 8F are cross-sectional views illustrating a manufacturing process of a first substrate of an organic light emitting display device according to an embodiment of the present invention.

9A to 9C are cross-sectional views illustrating a manufacturing process of a second substrate of an organic light emitting display device according to an embodiment of the present invention.

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

110: first substrate 150: second substrate

112 semiconductor layer 114 gate electrode

116: source electrode 118: drain electrode

142: connection pattern 144: connection electrode

152: first electrode 160: organic light emitting layer

162: second electrode

Claims (10)

First and second substrates facing each other and spaced apart from each other; A driving thin film transistor formed on an inner surface of the first substrate; A connection electrode connected to the driving thin film transistor and made of a conductive material having a first hardness; A first electrode formed on the entire inner surface of the second substrate; An organic light emitting layer formed under the first electrode; A second electrode formed under the organic light emitting layer and made of a conductive material in contact with the connection electrode and having a second hardness different from the first hardness; Organic electroluminescent device comprising a. The method of claim 1, And the first firmness is larger than the second firmness. The method of claim 2, The organic light emitting device, characterized in that the sawtooth irregularities are formed on the top surface of the connection electrode. The method of claim 1, An organic light emitting display device, characterized in that the lower portion of the connection electrode further comprises a connection pattern made of an insulating material having a height corresponding to the separation distance between the first and second substrates. The method of claim 1, The driving thin film transistor may include a gate electrode, an active layer, a source electrode, and a drain electrode. The method of claim 1, A gate wiring formed on the first substrate; A data line crossing the gate line; A power line parallel to the data line and spaced at a predetermined interval; A switching thin film transistor connected to the gate wiring, data wiring, and driving thin film transistor. An organic light emitting display device, characterized in that it further comprises. Forming a driving thin film transistor on the first substrate; Forming a connection electrode connected to the driving thin film transistor and made of a conductive material having a first hardness; Forming a first electrode on the second substrate; Forming an organic light emitting layer on the first electrode; Forming a second electrode on the organic light emitting layer, the second electrode including a conductive material having a second hardness different from the first hardness; Bonding the first and second substrates to contact the connection electrode and the second electrode; Method for producing an organic electroluminescent device comprising a. The method of claim 7, wherein The method of claim 1, wherein the first firmness is larger than the second hardness. The method of claim 8, The method of manufacturing an organic light emitting display device, characterized in that it further comprises the step of forming the sawtooth irregularities on the top surface of the connection electrode. The method of claim 7, wherein And forming a connection pattern made of an insulating material under the connection electrode.