KR20110012432A - Organic electro-luminescence device - Google Patents

Abstract

PURPOSE: An organic light emitting device is provided to reduce the overall thickness of an OLED by forming a second substrate in a metal foil and forming an external surface of the metal foil in convexo concave shape. CONSTITUTION: A driving thin film transistor(DTr) and an organic electroluminescent diode(E) are formed on a first substrate(101). A semiconductor layer(201) is formed on the first substrate. A gate insulating layer(203) is formed on the semiconductor layer. A second substrate(200) is bonded with the first substrate as being spaced from each other with an interval.

Description

Organic electroluminescent device

The present invention relates to organic electroluminescent devices, and more particularly, to encapsulation of organic electroluminescent devices.

Until recently, cathode ray tubes (CRT) have been mainly used as display devices. However, in recent years, flat panel such as plasma display panel (PDP), liquid crystal display device (LCD), organic electro-luminescence device (OLED), which can replace CRT Display devices are widely researched and used.

Among the flat panel display devices as described above, the organic light emitting display device (hereinafter referred to as OLED) is a self-light emitting device, and since the backlight used in the liquid crystal display device which is a non-light emitting device is not necessary, a light weight can be achieved.

In addition, the viewing angle and contrast ratio are superior to the liquid crystal display device, and it is advantageous in terms of power consumption, it is possible to drive the DC low voltage, the response speed is fast, and the internal components are solid, so it is strong against external shock, and the operating temperature range is also high. It has a wide range of advantages.

In particular, since the manufacturing process is simple, there is an advantage that can reduce the production cost more than the conventional liquid crystal display device.

OLEDs having these characteristics are largely divided into a passive matrix type and an active matrix type. The passive matrix type constitutes a device in a matrix form while crossing signal lines, whereas an active matrix type is a pixel. The thin film transistor, which is a switching element that turns on / off, and the driving thin film transistor which transmits current and the capacitor which maintains voltage for one frame are positioned per pixel.

In recent years, the passive matrix type has many limited elements such as resolution, power consumption, and lifespan. Accordingly, active matrix type OLEDs capable of realizing high resolution and large screens have been actively studied.

1 is a schematic cross-sectional view of a general active matrix OLED, and the OLED is a bottom emission method.

As shown, the OLED 10 is composed of a first substrate 1 and a second substrate 3 facing the first substrate 1, and the first and second substrates 1, 3 are mutually congruent. The edges thereof are spaced apart and sealed through a failure pattern 20.

In more detail, the driving thin film transistor DTr is formed in each pixel region on the first substrate 1, and the first electrode 11 and the first electrode connected to each driving thin film transistor DTr are formed. The organic light emitting layer 13 emitting light of a specific color on the electrode 11 and the second electrode 15 are formed on the organic light emitting layer 13.

The organic light emitting layer 13 expresses colors of red, green, and blue. In general, separate organic materials 13a, 13b, and 13c emitting red, green, and blue colors are used for each pixel.

The first and second electrodes 11 and 15 and the organic light emitting layer 13 formed therebetween form an organic light emitting diode. In this case, the OLED 10 having such a structure configures the first electrode 11 as an anode and the second electrode 15 as a cathode.

On the other hand, since the organic light emitting diodes are very sensitive to moisture and oxygen, researches on encapsulation of the OLED 10 for protecting the organic light emitting diodes from moisture and oxygen in the air have been actively conducted.

The present invention has been made to solve the above problems, and a first object of the present invention is to encapsulate an OLED effectively.

In addition, the second object is to minimize the distortion or warpage of the OLED, to effectively radiate the OLED, and the third object is to provide a lightweight and thin OLED.

In addition, the fourth object is to reduce the process cost of the OLED.

In order to achieve the object as described above, the present invention includes a first substrate formed with a driving thin film transistor and an organic light emitting diode; Provided is an organic electroluminescent device comprising a second substrate spaced apart from the first substrate, the second substrate made of a metal foil having a concave-convex shape of concave and convex portions on the opposite side facing the first substrate. do.

In addition, the present invention includes a first substrate formed with a driving thin film transistor and an organic light emitting diode; Provided is an organic light emitting display device including a second substrate spaced apart from the first substrate and bonded to the first substrate, the second substrate including a metal foil having a plurality of heat dissipation fins formed on an opposite side facing the first substrate.

In this case, the convex-concave shape has the convex portion embossed, and the second substrate has a thickness of 0.02 to 0.7 mm.

In addition, the uneven shape is formed by an etching process, the uneven shape is formed by etching 5 to 70% of the thickness of the second substrate.

In this case, the coefficient of thermal expansion of the metal foil is between 3.5 × 10 ^-6 ℃ ~ 4.5 × 10 ^-6 ℃, the difference in the coefficient of thermal expansion between the metal foil and the first substrate is within 30%.

An adhesive protective layer is formed between the first and second substrates, and an uneven shape is formed at a portion where the protective layer of the second substrate contacts.

In this case, a heat dissipation fin is formed at a portion where the protective layer of the second substrate contacts, and the protective layer has a hydrophobicity or a hygroscopic material, barium oxide (BaO) or calcium oxide (CaO).

In addition, a fan or heat sink is further configured on the outer surface of the second substrate.

As described above, as described above according to the present invention, by forming the second substrate of the OLED with a metal foil, and by forming the outer surface thereof in an uneven shape, there is an effect that can reduce the overall thickness of the OLED.

In addition, despite reducing the thickness of the OLED can improve the durability of the OLED itself, in particular, there is an effect that can minimize the occurrence of the curl (curl) or bending (bending) of the OLED.

In addition, there is an effect that can maximize the heat dissipation effect by dissipating heat generated from the OLED to the outside more effectively.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

2 is a schematic cross-sectional view of an OLED according to an exemplary embodiment of the present invention, and FIG. 3 is an enlarged cross-sectional view of a portion of FIG. 2.

Meanwhile, the OLED 100 is divided into a top emission type and a bottom emission type according to the transmitted direction of emitted light. Hereinafter, the bottom emission method will be described as an example.

As shown, the OLED 100 according to the present invention includes a first substrate 101 having a driving and switching thin film transistor DTr (not shown) and an organic light emitting diode E, and a second for encapsulation. It consists of the board | substrate 200.

Here, the semiconductor layer 201 is formed on the first substrate 101. The semiconductor layer 201 is made of silicon, and the central portion thereof has a high concentration of impurities on both sides of the active region 201a and the active region 201a. The doped source and drain regions 201b and 201c are formed.

The gate insulating film 203 is formed on the semiconductor layer 201.

A gate electrode 205 and a gate wiring extending in one direction are formed on the gate insulating film 203 so as to correspond to the semiconductor layer 201a.

In addition, a first interlayer insulating film 207a is formed on the entire surface of the gate electrode 205 and the gate wiring (not shown). At this time, the first interlayer insulating film 207a and the gate insulating film 203 below are formed in an active region ( 201a) first and second semiconductor layer contact holes 209a and 209b exposing the source and drain regions 201b and 201c located at both sides thereof, respectively.

Next, an upper portion of the first interlayer insulating layer 207a including the first and second semiconductor layer contact holes 209a and 209b is spaced apart from each other and exposed through the first and second semiconductor layer contact holes 209a and 209b. And source and drain electrodes 211 and 213 in contact with the drain regions 201b and 201c, respectively.

And a second interlayer having a drain contact hole 215 exposing the drain electrode 213 over the first interlayer insulating film 207a exposed between the source and drain electrodes 211 and 213 and the two electrodes 211 and 213. The insulating film 207b is formed.

At this time, the semiconductor layer 201 including the source and drain electrodes 211 and 213 and the source and drain regions 201b and 201c in contact with the electrodes 211 and 213 and the gate insulating layer formed on the semiconductor layer 201. The 203 and the gate electrode 205 form a driving thin film transistor DTr.

Although not shown in the drawing, data wirings (not shown) defining pixel areas are formed to cross the gate wirings (not shown).

In addition, the first electrode 111 constituting the organic light emitting diode E, the organic light emitting layer 113, and the second electrode 115 are sequentially disposed in an area that substantially displays an image on the second interlayer insulating film 207b. It is formed.

The first and second electrodes 111 and 115 and the organic light emitting layer 113 formed therebetween form an organic light emitting diode (E).

The first electrode 111 is connected to the drain electrode 213 of the driving thin film transistor DTr.

In this case, the first electrode 111 is a transparent conductive material having a relatively large work function value, such as indium tin oxide (ITO) or indium zinc oxide (IZO), to serve as an anode electrode. It is preferable to form as.

In addition, the second electrode 115 may be made of an opaque conductive material to serve as a cathode.

Here, the second electrode 115 is a metal material having a relatively low work function, for example, aluminum (Al), aluminum alloy (AlNd), silver (Ag), magnesium (Mg), gold (Au), aluminum magnesium alloy It is preferable to form with one substance selected from (AlMg).

Accordingly, the light emitted from the organic light emitting layer 113 is driven by the bottom emission method emitted in the direction of the first electrode 111.

Here, the organic light emitting layer 113 may be composed of a single layer made of a light emitting material, and in order to increase the light emitting efficiency, a hole injection layer, a hole transporting layer, an emitting material layer, an electron It may be composed of multiple layers of an electron transporting layer and an electron injection layer.

A bank 221 is positioned between the first electrodes 111 formed in each pixel region.

That is, the bank 221 is formed in a matrix type having a lattice structure as a whole, and the bank 221 is formed as a structure in which the first electrode 111 is separated by pixel region with the boundary portion of each pixel region. .

When a predetermined voltage is applied to the first electrode 111 and the second electrode 115 according to the selected color signal, the OLED 100 is injected into the electrons and the second electrode 115 provided from the first electrode 111. The holes are transported to the organic light emitting layer 113 to form excitons, and when the excitons transition from the excited state to the ground state, light is generated and emitted in the form of visible light.

At this time, since the emitted light passes through the transparent first electrode 111 to the outside, the OLED 100 implements an arbitrary image.

The second substrate 200 is disposed on the driving thin film transistor DTr and the organic light emitting diode E, and the first and second substrates 101 and 200 are formed through the protective layer 120 having adhesiveness. Are spaced apart from each other.

Through this, the OLED 100 is encapsulated.

In this case, the protective layer 120 may include barium oxide (BaO) or calcium oxide (CaO) having a hydrophobic property or a hygroscopic property therein. As a result, the protective layer 120 itself may be hydrophobic to prevent moisture penetration or to prevent contact with the organic light emitting layer 113 due to moisture absorption even when moisture penetrates into the protective layer 120. .

As described above, in the OLED 100 of the present invention, the protective layer 120 is formed directly on the organic light emitting diode E, thereby eliminating the existing failure turn (20 in FIG. 1).

Thus, made of a conventional polymer material, as the temperature is heated or stored for a long time to prevent the problem that the pollutant such as water or gas from the outside penetrates into the OLED 100 from the outside through the failure turn (20 in Figure 1). can do.

In addition, the OLED 100 of the present invention does not cause the OLED 100 to be pressed by the protective layer 120 even when a pressure such as pressing from the outside is applied, and thus the first and second of the organic light emitting diode E Cracks in the electrodes 111 and 115 or the driving thin film transistor DTr may be prevented.

As a result, problems such as dark spot defects may be prevented from occurring, thereby preventing the problem of uneven brightness or image characteristics.

On the other hand, the first substrate 101 may be formed of glass, stainless steel (stainless steel) or the like, the OLED 100 of the present invention is a bottom-emitting OLED (100) it is preferable to use a transparent glass. Do.

In addition, the second substrate 200 of the present invention is characterized in that the metal foil (metal foil), in particular, the outer surface of the second substrate 200 by the etching (etching) process to the concave portion and the convex portion It is characterized by having an uneven shape (grooving pattern: 210) made.

As such, by forming the second substrate 200 with a metal foil, the second substrate 200 can be formed to a thin thickness as compared with the case of forming the second substrate with glass, thereby reducing the overall thickness of the OLED 100. Can be.

In addition, despite reducing the thickness of the OLED 100 can improve the durability of the OLED 100 itself, it is also possible to improve the heat dissipation characteristics of the OLED (100).

In particular, by forming the concave-convex shape 210 on the outer surface of the second substrate 200, the second substrate (metal foil: 200) is formed of a material different from the first substrate (glass: 101) to form the first substrate ( Curvature or bending due to a difference in thermal expansion between the second substrate 200 and the second substrate 200 may be minimized.

In addition, the heat generated by the OLED 100 is more effectively emitted to the outside. We will discuss this in more detail later.

4 is a perspective view schematically illustrating a second substrate of an OLED according to an exemplary embodiment of the present invention, and FIGS. 5A to 5B illustrate a curl or bending phenomenon of a general OLED and an OLED according to an exemplary embodiment of the present invention. It is a result of comparing and measuring.

As shown in FIG. 4, the second substrate 200 is made of a metal foil. If one surface of the second substrate 200 facing the organic light emitting diode (E in FIG. 3) is defined as an inner surface. The outer surface of the second substrate 200 is formed into a concave-convex shape 210 formed of a concave portion and a convex portion.

As such, when the outer surface of the second substrate 200 is formed into the uneven shape 210, stress is generated to the outer surface of the second substrate 200 by the uneven shape 210, and thus, the OLED (FIG. Curvature or bending of 100 of 3 may be minimized.

This will be described in more detail with reference to FIGS. 5A to 5B.

Prior to the description, the OLED (100 in FIG. 3) is an OLED (100 in FIG. 3) in which a first substrate (101 in FIG. 3) is formed of a glass material and a second substrate 200 is formed of a metal foil. The torsion or warpage measurement of 100 of FIG. 3 divides the four edges of the OLED (100 of FIG. 3) into 12 points, and the height of each point is based on the difference between the centers of the OLED (100 of FIG. 3). It is a result of a measurement.

First, Figure 5a is a result of measuring the twist or warpage of a typical OLED.

Referring to this, the first substrate (glass: 101 in FIG. 3) and the second substrate (metal foil: 200) are made of different materials, and the first and second substrates (101, 200 in FIG. 3) have different thermal expansions. Coefficients cause shrinkage and deformation of different values.

As a result, the OLED (100 of FIG. 3) may have a curling or bending phenomenon. The twisting or bending phenomenon may be caused by a metal foil having a higher coefficient of thermal expansion than that of the glass, that is, the second substrate 200. As compared with the first substrate (101 of FIG. 3), the OLED (100 of FIG. 3) is warped or warped so that both edges facing each other in the direction in which the second substrate 200 is formed are close to each other.

When such distortion or bending occurs, the driving circuit (not shown) is misaligned in the module process of attaching the driving circuit (not shown), so that a line defect and a driving defect are generated or a polarizing plate A defect occurs in the attaching process (not shown), which acts as a defect that greatly reduces the image quality of the OLED (100 in FIG. 3).

At this time, when the concave-convex shape 210 is formed on the outer surface of the metal foil, that is, the second substrate 200 according to the embodiment of the present invention, the concave-convex shape 210 to the outer surface of the second substrate 200. The stress is generated, and the stress thereof cancels the shrinkage and deformation of the second substrate 200 to minimize the curl or bending of the OLED (100 of FIG. 3).

The contents thereof can be confirmed with reference to FIG. 5B.

That is, FIG. 5B is an OLED (100 in FIG. 3) having an uneven shape 210 formed on an outer surface of the second substrate 200 made of a metal foil, which is different from each other in the direction in which the second substrate 200 is formed. It can be seen that the warpage or warpage phenomenon in which the opposite edges face each other are alleviated.

At this time, the thermal expansion coefficient of the metal foil of the second substrate 200 is preferably between 3.5 × 10 ^-6 ℃ ~ 4.5 × 10 ^-6 ℃.

Therefore, it is preferable that the difference of the thermal expansion coefficient between the 1st board | substrate (101 of FIG. 3) and the 2nd board | substrate 200 formed from glass does not exceed 30%.

This means that when the difference in thermal expansion coefficient between the first substrate (101 in FIG. 3) and the second substrate 200 is 30% or more, the OLED (not shown in FIG. 3) is formed even when the uneven shape 210 is formed on the outer surface of the second substrate 200. This is because torsion or bending of 100) may occur significantly.

In addition, by forming the outer surface of the second substrate 200 in the uneven shape 210 as described above, the outer surface of the second substrate 200 has a maximum surface area.

Therefore, the high heat generated from the OLED (100 of FIG. 3) is effectively released to the outside by the large surface area, thereby maximizing a heat radiation effect.

That is, the temperature of the OLED (100 in FIG. 3) is increased to about 80 to 90 ° C. by heat generated with deterioration of the driving thin film transistor DTr during driving. Due to such high temperature, the lifetime of the OLED (100 in FIG. 3) is drastically reduced.

Therefore, the heat dissipation generated in the OLED (100 in FIG. 3) through the second substrate 200 of the OLED (100 in FIG. 3) is to prevent a problem in which the life of the OLED (100 in FIG. 3) is rapidly reduced. .

The concave-convex shape 210 may have a high heat dissipation effect as the concave and convex portions are formed to increase the surface area capable of dissipating heat of the OLED (100 of FIG. 3) transferred to the second substrate 200. .

Here, the uneven shape 210 is not particularly proposed.

The uneven shape 210 of the outer surface of the second substrate 200 is formed through an etching process of the outer surface of the second substrate 200.

At this time, the thickness of the second substrate 200 is preferably formed to 0.02 ~ 0.7mm, the uneven shape 210 is 5 ~ 70% of the thickness of the second substrate 200 by the etching (etching) process It is preferable to form.

Table 1 below is a result of simulation measurement of the temperature inside the OLED (100 in FIG. 3).

1 point (℃) 2 point (℃) 3 point (℃) 4 point (℃) 5 point (℃) 6 point (℃) Average (℃) Material1 38 37.6 34.6 40.0 38.5 37.0 37.6 Material2 35.7 34.9 35.2 37.0 36.4 35.0 35.7 Material3 34.9 34.0 34.6 36.7 36.0 34.8 35.1

Table (1)

Table 1 is a result of measuring the temperature of 6 points arbitrarily defined on the screen on which the image is implemented after driving the OLED (100 in FIG. 3) in full color.

Here, material 1 represents an OLED using a second substrate composed of glass, material 2 is an OLED using a second substrate composed of metal foil, and material 3 represents a second substrate composed of metal foil according to an embodiment of the present invention. An OLED (100 in FIG. 3) formed with the outer surface of the concave-convex shape 210 is shown.

Referring to Table 1, it can be seen that the temperature of the OLED of Material 3 (100 in FIG. 3) is much lower than that of Material 1 and Material 2.

This, when the second substrate 200 is formed of a metal foil according to an embodiment of the present invention and the outer surface of the second substrate 200 is formed in the concave-convex shape 210, the second substrate 200 is glass It can be seen that it can have a more efficient heat dissipation effect than that formed by or formed with a common metal foil.

As described above, the second substrate 200 of the OLED (100 in FIG. 3) is formed of a metal foil, and the outer surface thereof is formed into an uneven shape 210, thereby resulting in high heat generated from the OLED (100 in FIG. 3). It can be effectively released to the outside to maximize the heat dissipation effect.

In addition, a fan (not shown) or a heat sink (not shown) is further configured in the OLED (100 of FIG. 3) according to an exemplary embodiment of the present invention, so that the heat dissipation effect of the OLED (100 of FIG. 3) may be improved. It can be maximized further.

6 is a graph showing a temperature change inside the OLED (100 of FIG. 3) according to whether or not a heat sink is included.

Here, sample 1 represents an OLED using a second substrate made of glass, sample 2 is further provided with a heat sink in the OLED using a second substrate made of glass, sample 3 is a metal foil according to an embodiment of the present invention An OLED (100 in FIG. 3) having an outer surface of the configured second substrate 200 formed in the uneven shape 210 is illustrated, and sample 4 shows a heat sink in the OLED (100 in FIG. 3) having the uneven shape 210 formed therein. It is the result of having measured further including (not shown).

In general, the heat sink (not shown) uses a high thermal conductivity metal plate or carbon sheet (carbon sheet).

Referring to FIG. 6, it can be seen that the temperature inside the OLED (100 of FIG. 3) of sample 4 is the lowest. Through this, the uneven shape 210 is formed on the outer surface of the second substrate 200. By further configuring the fan (not shown) or the heat sink (not shown) on the outer surface of the second substrate 200, it can be seen that the heat dissipation effect of the OLED (100 of FIG. 3) can be further maximized.

On the other hand, by forming the second substrate 200 formed of a metal foil so as to have a thickness of 0.02 ~ 0.05mm, it is possible to make the second substrate 200 has a very flexible characteristics.

As a result, as portable portable devices such as laptops and personal digital assistants (PDAs) are widely used in recent years, OLEDs (100 in FIG. 3), which are lighter, lighter, and more flexible than glass, can be applied to them. have.

In this case, the first substrate (101 in FIG. 3) is also preferably composed of flexible glass having flexible characteristics.

FIG. 7A is a perspective view schematically illustrating a second substrate of an OLED according to another embodiment of the present invention, and FIG. 7B is a bottom perspective view schematically illustrating the rear surface of FIG. 7A.

As shown in FIG. 7A, the convex portion of the concave-convex shape 210 formed of the concave portion and the convex portion formed on the outer surface of the second substrate 200 may be formed in an embo shape.

As such, even when the convex portion of the concave-convex shape 210 is formed into an embossed shape, stress is generated on the outer surface of the second substrate 200 by the concave-convex shape 210, and the outer surface of the second substrate 200 is formed. The surface area can be maximized.

Through this, curvature or bending of the OLED (100 of FIG. 3) can be minimized, and a large surface area effectively radiates high heat generated from the OLED (100 of FIG. 3) to the outside to radiate heat. To maximize.

In addition, as shown in FIG. 7B, the inner side edge of the second substrate 200 is also formed as a concave-convex shape 210 having concave and convex portions, which is the second substrate 200 and the protective layer (see FIG. 3). This is to widen the adhesive area with 120).

Through this, the second substrate 200 is improved in adhesion with the protective layer (120 in FIG. 3).

Alternatively, as shown in FIGS. 8A to 8B, a plurality of heat dissipation fins 220 may be configured on the outer surface of the second substrate 200.

The heat dissipation fin 220 is configured to protrude from the outer surface of the second substrate 200 at a predetermined height spaced apart.

The shape of the heat dissipation fin 220 may be freely formed as necessary, but the plurality of heat dissipation fin 220 is formed to protrude in a direction in which heat is transmitted, thereby causing stress to occur on the outer surface of the second substrate 200. It is preferable that the surface area of the outer surface of the second substrate 200 is maximized.

Accordingly, curvature or bending of the OLED (100 of FIG. 3) may be minimized, and the heat generated when driving the OLED (100 of FIG. 3) may be more efficiently radiated to the outside by the large surface area. Can be.

In particular, as the heat dissipation fins 220 are formed more, the surface area capable of dissipating the heat of the OLED (100 in FIG. 3) transferred to the second substrate 200 may be wider, and thus may have a higher heat dissipation effect. A plurality of heat dissipation fins 220 must be formed within the limit of maintaining a predetermined interval between the heat dissipation fins 220 so that natural convection can pass through them.

In addition, although not shown, in order to widen the adhesive area with the protective layer (120 of FIG. 3), an inner side edge of the second substrate 200 having the heat dissipation fins 220 formed thereon may form an uneven shape or a plurality of heat dissipation fins. .

As described above, the first substrate (glass: 101 in FIG. 3) is formed by forming the second substrate 200 of the OLED (100 in FIG. 3) with a metal foil and forming the outer surface thereof into the uneven shape 210. Curvature or bending of the OLED (100 of FIG. 3) can be minimized even if the second substrate (metal foil: 200) is made of a different material, and is generated from the OLED (100 of FIG. 3). By discharging the high heat effectively to the outside, the heat dissipation effect can be maximized.

In addition, the OLED of the present invention (100 in FIG. 3) is formed directly on the organic light emitting diode (E in FIG. 3) to form a protective layer (120 in FIG. 3), thereby eliminating the conventional failure turn (20 in FIG. 1). Can be.

Thus, made of a conventional polymer material, as the temperature is heated or stored for a long time, a pollutant such as water or gas from the outside penetrates into the OLED (100 in FIG. 3) from the outside through a failure turn (20 in FIG. 1). The problem can be prevented.

In addition, in the OLED of the present invention (100 in FIG. 3), even if a pressure such as pressing from the outside is applied, the pressing of the OLED (100 in FIG. 3) does not occur by the protective layer (120 in FIG. 3). Cracks in the first and second electrodes (111 and 115 in FIG. 3) or the driving thin film transistor (DTr in FIG. 3) of the diode (E of FIG. 3) may be prevented.

As a result, problems such as dark spot defects may be prevented from occurring, thereby preventing the problem of uneven brightness or image characteristics.

The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.

1 is a schematic cross-sectional view of a typical active matrix type OLED.

2 is a cross-sectional view schematically showing an OLED according to an embodiment of the present invention.

3 is an enlarged cross-sectional view of a portion of FIG. 2;

4 is a perspective view schematically showing a second substrate of an OLED according to an embodiment of the present invention;

5a to 5b are a result of measuring the twist (bending) or bending (bending) of the general OLED and the OLED according to an embodiment of the present invention.

6 is a graph showing a temperature change inside an OLED depending on whether a heat sink is included.

7A is a perspective view schematically showing a second substrate of an OLED according to a second embodiment of the present invention;

FIG. 7B is a bottom perspective view schematically showing the back side of FIG. 7A; FIG.

8A-8B are perspective views schematically showing a second substrate of an OLED according to another third embodiment of the present invention.

Claims (13)

A first substrate on which a driving thin film transistor and an organic light emitting diode are formed; The second substrate is spaced and bonded to the first substrate, the second substrate made of a metal foil having a concave-convex shape consisting of concave and convex portions on the opposite side facing the first substrate. Organic electroluminescent device comprising a. A first substrate on which a driving thin film transistor and an organic light emitting diode are formed; The second substrate is spaced apart and bonded to the first substrate, the second substrate made of a metal foil having a plurality of heat dissipation fins on the opposite side facing the first substrate. Organic electroluminescent device comprising a. The method of claim 1, The concave-convex shape of the organic light emitting device of the embossed portion of the convex portion. The method according to any one of claims 1 and 2, The second substrate is an organic light emitting device having a thickness of 0.02 ~ 0.7mm. The method according to any one of claims 1 and 2, The uneven shape is an organic light emitting device formed by an etching process. The method of claim 5, The concave-convex shape is formed by etching 5 to 70% of the thickness of the second substrate. The method according to any one of claims 1 and 2, The thermal expansion coefficient of the metal foil is between 3.5 × 10 ^-6 ℃ ~ 4.5 × 10 ^-6 ℃ organic light emitting device. The method of claim 7, wherein And a difference in thermal expansion coefficient between the metal foil and the first substrate is within 30%. The method according to any one of claims 1 and 2, An organic light emitting display device having an adhesive protective layer formed between the first and second substrates. The method of claim 9, An organic light emitting diode having a concave-convex shape in a portion where the protective layer of the second substrate is in contact. The method of claim 9, An organic light emitting display device having a heat dissipation fin formed at a portion of the second substrate to be in contact with the protective layer. The method of claim 9, The protective layer has a hydrophobicity or an organic electroluminescent device comprising a barium oxide (BaO) or calcium oxide (CaO) that is a hygroscopic material. The method according to any one of claims 1 and 2, The organic light emitting device further comprises a fan or a heat sink on the outer surface of the second substrate.

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