KR20120046427A - Flexible organic light emitting diode - Google Patents

Abstract

PURPOSE: A flexible organic electro luminescence device is provided to control the oxidation and corrosion of an electrode layer and prevent short circuit and current leakage by preventing moisture and oxygen from being penetrated from outside. CONSTITUTION: A substrate(101) defining a storage area inside is prepared. A driving thin film transistor(DTr) and an organic electroluminescent diode(E) are formed on the substrate. The organic electroluminescent diode comprises a first electrode(111), an organic light emitting layer(113), and a second electrode(115). A top encapsulation layer(130) covers the driving thin film transistor and the organic electroluminescent diode. A lower encapsulation layer(140) is formed by alternatively laminating an organic film and an inorganic film inside the storage area.

Description

Flexible organic light emitting diodes

The present invention relates to an organic light emitting display device, and more particularly, to a flexible organic light emitting display device for preventing penetration of moisture and oxygen from the outside.

Until recently, cathode ray tubes (CRT) have been mainly used as display devices. However, in recent years, flat panel displays such as plasma display panels (PDPs), liquid crystal display devices (LCDs), and organic light emitting diodes (OLEDs), which can replace CRTs, can be used. Devices are being 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 also possible to drive DC low voltage, has a fast response speed, and the internal components are solid, so it is strong against external shock and has a wide temperature range. It has 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.

Recently, flexible OLEDs manufactured to maintain display performance even when bent like paper using flexible materials such as flexible glass substrates and plastics are emerging as next-generation flat panel displays.

Such a flexible OLED is a self-light emitting device that emits light through an organic light emitting diode, and the organic light emitting diode emits light through an organic light emitting phenomenon.

On the other hand, the substrate of the flexible OLED has a light weight, excellent impact resistance and low cost, while the external moisture or oxygen easily penetrates.

When oxygen or moisture flows into the flexible OLED, electroluminescence causes oxidation and corrosion of the electrode layer.In this case, the risk of current leakage and short circuiting increases, resulting in pixel defects, which eventually causes There is a problem of shortening the life.

In recent years, such flexible OLEDs are increasingly used in portable computers as well as desktop computer monitors and wall-mounted televisions, and are actively researched to have a large display area and dramatically reduced weight and volume. It's going on.

Therefore, it is desired to form the bezel area of the outer edge of the non-light emitting area except the effective light emitting area where the image is displayed as small as possible.

The present invention has been made in view of the above problems, and a first object of the present invention is to provide a flexible organic electroluminescent device in which oxygen and moisture cannot penetrate inside.

Through this, the second object is to prevent oxidation and corrosion of the electrode layer, and to prevent the occurrence of current leakage and short circuit, and the third object is to prevent occurrence of pixel defects and reduced lifetime.

In addition, a fourth object of the present invention is to provide a flexible OLED having a narrow bezel.

In order to achieve the object as described above, the present invention comprises a substrate consisting of a bottom surface and the four edges of the bottom is bent upward, defining a receiving area therein; A lower encapsulation layer formed by alternately stacking at least one organic film and at least one inorganic film inside the storage area; A driving thin film transistor formed on the lower encapsulation layer and an organic light emitting diode connected to the driving thin film transistor, the organic light emitting diode connected to the driving thin film transistor; Provided is a flexible organic light emitting display device including an upper encapsulation layer covering the driving thin film transistor and the organic light emitting diode.

In addition, the present invention is a substrate; A partition wall formed around four edges of the substrate; A lower encapsulation layer formed by alternately stacking at least one organic film and at least one inorganic film inside the partition wall; A driving thin film transistor and an organic light emitting diode formed on the lower encapsulation layer; Provided is a flexible organic light emitting display device including an upper encapsulation layer covering the driving thin film transistor and the organic light emitting diode.

Here, the inorganic film is formed of a structure surrounding the organic film, the inorganic film is formed along the bottom surface of the substrate and the side surface of the substrate or the inner surface of the partition wall, the organic film corresponding to the bottom surface of the substrate Is formed on the phase.

In addition, the inorganic film is formed along the inner surface of the partition wall, the organic film is formed on the inorganic film corresponding to the bottom surface of the substrate, the inorganic film is composed of the first to fourth inorganic film, the organic film is The first inorganic layer is formed along the inner surface of the bottom and side surfaces of the substrate, and the first organic layer is surrounded by the first inorganic layer and the side and the bottom surface thereof. The second inorganic layer is formed along the inner surface of the upper side of the first organic layer and the side surface of the substrate, the second organic layer is surrounded by the side and the lower surface by the second inorganic layer is positioned, A third inorganic film is formed along the inner surface of the upper side of the second organic film and the side surface of the substrate, the third organic film is located on the side and the lower surface is wrapped by the third inorganic film, the third The fourth inorganic layer is positioned on the organic layer and the third inorganic layer.

The inorganic layer may include first to fourth inorganic layers, the organic layer may include first to third organic layers, the first inorganic layer may be formed on the substrate, and the first organic layer may be formed in the partition wall. A side surface of the first inorganic film is surrounded by a lower surface and the partition wall, the second inorganic film is formed along an upper surface of the first organic film and an inner surface of the partition wall, and the second organic film is A side surface and a bottom surface are surrounded by a second inorganic layer, and the third inorganic layer is formed along an upper surface of the second organic layer and an inner surface of the partition wall, and the third organic layer is formed by the third inorganic layer. The lower and lower surfaces are wrapped, and the fourth inorganic layer is positioned on the third organic layer and the third inorganic layer.

In addition, the first to fourth inorganic layers are formed on the upper side of the substrate, the third inorganic layer and the third organic layer formed on the upper side of the substrate form the same plane, the first to fourth An inorganic film is formed on the partition wall, and the third inorganic film and the third organic film formed on the partition wall form the same plane.

Herein, the inorganic layer is made of one selected from silicon oxide film (SiO 2), silicon nitride (SixNy), silicon oxynitride film (SiON), aluminum oxide (AlOx), aluminum nitride (Alon), TIO, and ZnO. Acrylate monomer, phenylacetylene, diamine and dianhydride, siloxane, silane, parylene, olefin polymer (polyethylene, polypropylene) , Polyethylene terephthalate (PET), fluororesin (fluororesin), polysiloxane (polysiloxane) is made of one selected from, the substrate is composed of a flexible glass substrate (plastic) or one selected from.

The driving thin film transistor may include a semiconductor layer, a gate electrode, a source and a drain electrode, and the organic light emitting diode may include a first electrode, an organic light emitting layer, and a second electrode connected to the driving thin film transistor.

As described above, the barrier layer is formed by alternately stacking an inorganic film and an organic film in a receiving region defined by forming sidewalls or partition walls on the flexible substrate of the flexible organic light emitting device according to the present invention. By this position, through this, oxygen and moisture can not penetrate inside, there is an effect to prevent oxidation and corrosion of the electrode layer, there is an effect to prevent the occurrence of current leakage and short circuit, pixel There is an effect that can prevent the occurrence of defects and reduced life.

In addition, the barrier layer has an effect of preventing the problem of increasing the bezel area of the flexible organic light emitting device, it is possible to provide a flexible organic light emitting device having a narrow bezel (narrow bezel).

1 is a cross-sectional view schematically showing a flexible OLED according to an embodiment of the present invention.
Figure 2 is an enlarged cross-sectional view showing the edge of the barrier film of Figure 1;
3 is a sectional view schematically showing a flexible OLED according to a first embodiment of the present invention;
4 is an enlarged cross-sectional view of a portion of FIG. 3;
5 is a sectional view schematically showing a flexible OLED according to a second embodiment of the present invention.

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

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

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

As shown, the flexible OLED 100 includes a driving thin film transistor DTr and an organic light emitting diode E formed on the substrate 101.

In more detail, a switching thin film transistor (not shown), a driving thin film transistor (DTr), and a storage capacitor (not shown) are formed in each pixel area P on the substrate 101. The organic light emitting layer 113 and the organic light emitting layer 113 which are positioned on the first electrode 111 and the first electrode 111 connected to each driving thin film transistor DTr and emit light of a specific color, An organic light emitting diode E including the second electrode 115 positioned above is formed.

In this case, the first electrode 111 is formed of a material having a relatively high work function, and the first electrode 111 is formed for each pixel region P. FIG.

In addition, 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 transport layer, an emitting material layer, an electron It may be composed of multiple layers of an electron transport layer and an electron injection layer.

The organic light emitting layer 113 expresses the colors of red (R), green (G), and blue (B). As a general method, red (R), green (G), and blue for each pixel area (P). (B) A separate organic material that emits color is used as a pattern.

In addition, the second electrode 115 has a double layer structure, and a double layer structure in which a transparent conductive material is thickly deposited on a semitransparent metal film in which a thin metal material having a low work function is deposited.

Therefore, the light emitted from the organic light emitting layer 113 is driven by the top emission method emitted toward the second electrode 115.

When a predetermined voltage is applied to the first electrode 111 and the second electrode 115 according to the selected color signal, the flexible OLED 100 may inject holes and second electrodes 115 injected from the first electrode 111. Electrons provided from the organic light emitting layer 113 are transported to form an exciton, and when the exciton transitions from the excited state to the ground state, light is generated and emitted in the form of visible light.

At this time, the emitted light passes through the transparent second electrode 115 to the outside, so that the flexible OLED 100 implements an arbitrary image.

In addition, a protective film 130 in the form of a thin thin film is formed on the driving thin film transistor DTr and the organic light emitting diode E. The flexible OLED 100 of the present invention has a protective film 130 which is an upper encapsulation layer. ) Is encapsulated.

In order to prevent external oxygen and moisture from penetrating into the flexible OLED 100, the protective film 130 is laminated with at least two inorganic protective films 130a and 130c, wherein two inorganic protective films ( It is preferable that the organic protective film 130b is interposed between the 130a and 130c to secure the impact resistance of the inorganic protective films 130a and 130c.

On the other hand, the flexible OLED 100 of the present invention has a flexible characteristic, so that the display performance is maintained as it is, even if bent like a paper, the substrate 101 is composed of a flexible (flexible) glass substrate or plastic having a flexible characteristic, such a The substrate 101 has a disadvantage in that penetration of external moisture or oxygen is easy.

Thus, the flexible OLED 100 prevents the penetration of external oxygen and moisture through the protective film 130, and allows the external oxygen and moisture to penetrate into the flexible OLED 100 through the substrate 101.

When oxygen or moisture is introduced into the flexible OLED 100 through the substrate 101, oxidation and corrosion of the electrode layer are generated while electroluminescence is performed, and in this case, the risk of current leakage and short circuiting increases, and the pixel is increased. There is a problem that a failure occurs and eventually reduce the life of the display device itself.

Therefore, the flexible OLED 100 of the present invention further includes a barrier layer 140 as a lower encapsulation layer between the substrate 101, the driving thin film transistor DTr, and the organic light emitting diode E. The layer 140 includes a plurality of layers in which at least one inorganic insulating material 110a, 110b, 110c and 110d and at least one organic insulating material 120a, 120b and 120c are alternately stacked.

That is, the barrier layer 140 of the flexible OLED 100 of the present invention includes at least first to fourth inorganic barrier layers 110a, 110b, 110c, and 110d and first to third organic barrier layers 120a, 120b, and 120c. )

At this time, the first to fourth inorganic barrier layer (110a, 110b, 110c, 110d) serves to prevent the penetration of oxygen and moisture, the first to third organic barrier layer (120a, 120b, 120c) is the first It serves to secure the impact resistance of the fourth inorganic barrier layer (110a, 110b, 110c, 110d).

In the structure in which the organic barrier layers 120a, 120b, and 120c and the inorganic barrier layers 110a, 110b, 110c, and 110d are alternately stacked, moisture and oxygen are formed through the side surfaces of the organic barrier layers 120a, 120b, and 120c. Since the inorganic barrier layer (110a, 110b, 110c, 110d) to completely enclose the organic barrier layer (120a, 120b, 120c) is to be prevented from penetrating.

Therefore, the flexible OLED 100 according to the embodiment of the present invention may be made of a flexible glass substrate or plastic, which is easily penetrated by external moisture or oxygen, even though the substrate 101 is formed from the outside through the barrier layer 140. Moisture and oxygen can be prevented from penetrating into the flexible OLED 100.

Thus, due to the oxygen or moisture introduced into the inside, oxidation and corrosion of the electrode layer may be prevented from occurring, and thus, the emission characteristics of the organic light emitting layer (113 of FIG. 1) are lowered, and the organic light emitting layer (113 of FIG. 1). This can prevent the problem of shortening the lifespan.

In addition, current leakage and short circuits can be prevented from occurring, and pixel defects can be prevented from occurring. This prevents the problem of uneven brightness or image characteristics.

Meanwhile, referring to FIG. 2, when the edge of the barrier film 140 formed on the substrate 101 is enlarged, the second inorganic barrier layer 110b formed to completely cover the first organic barrier layer 120a may be formed. Since the step coverage property is not good, the second inorganic barrier layer 110b is formed along the step of the first organic barrier layer 120a.

Therefore, the flatness of the second inorganic barrier layer 110b corresponding to the end of the first organic barrier layer 120a is not good, and thus the second organic barrier layer 120b is formed on the second inorganic barrier layer 110b. In the process, it is preferable that the second organic barrier layer 120b is formed to be concaved into the second inorganic barrier layer 110b as compared with the first organic barrier layer 120a.

At this time, the second organic barrier layer 120b is recessed and formed at least as much as A 'from the end of the first organic barrier layer 120a by the poor step coverage of the second inorganic barrier layer 110b. Preferably, the third inorganic barrier layer 110c formed on the second organic barrier layer 120b may also have a third organic barrier layer 120c as compared to the second organic barrier layer 120b. It is preferable to form it so that it may infiltrate inward as much as A 'area | region from the end of 120b.

However, such a configuration causes a problem of increasing the bezel area A of the flexible OLED 100.

- First Embodiment -

3 is a schematic cross-sectional view of a flexible OLED according to a first exemplary embodiment of the present invention, and FIG. 4 is an enlarged cross-sectional view of a portion of FIG. 3.

In the first embodiment of the present invention, a top emission type will be described as an example.

As illustrated, the flexible OLED 100 according to the first embodiment of the present invention encapsulates a substrate 101 on which a driving thin film transistor DTr and an organic light emitting diode E is formed by a protective film 130. It is encapsulated.

Looking at this in more detail, the barrier layer 140 is formed on the substrate 101 to prevent the penetration of moisture and oxygen to the inside of the flexible OLED (100).

In this case, the flexible OLED 100 according to the first exemplary embodiment of the present invention can solve the problem in which the bezel region (A of FIG. 2) is increased by the barrier layer 140. We will discuss this in more detail later.

The semiconductor layer 201 is formed in the pixel region P on the barrier layer 140. The semiconductor layer 201 is made of silicon, and a central portion thereof is formed on both sides of the active region 201a and the active region 201a. It is composed of source and drain regions 201b and 201c doped with a high concentration of impurities.

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.

On the other hand, although not shown in the figure, data wirings (not shown) defining the pixel region P are formed to cross the gate wirings (not shown). The switching thin film transistor (not shown) has the same structure as the driving thin film transistor DTr and is connected to the driving thin film transistor DTr.

In addition, the switching thin film transistor (not shown) and the driving thin film transistor DTr in the drawing show a top gate type in which the semiconductor layer 201 is made of a polysilicon semiconductor layer as an example. It may be formed of a bottom gate type made of amorphous silicon of impurities.

In addition, the organic light emitting diode is formed of a material having a relatively high work function, for example, in a region connected to the drain electrode 213 of the driving thin film transistor DTr and substantially displaying an image on the second interlayer insulating film 207b. As one component constituting (E), a first electrode 111 constituting an anode is formed.

The first electrode 111 is formed for each pixel region P, and a bank 221 is positioned between the first electrodes 111 formed for each pixel region P. FIG.

In other words, the bank 221 is formed as a boundary portion for each pixel region P, and the first electrode 111 is formed in a separate structure for each pixel region P. FIG.

The organic light emitting layer 113 is formed on the first electrode 111.

Here, the organic light emitting layer 115 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 transport layer, an emitting material layer, an electron It may be composed of multiple layers of an electron transport layer and an electron injection layer.

The organic light emitting layer 113 expresses the colors of red (R), green (G), and blue (B). As a general method, red (R), green (G), and blue for each pixel area (P). (B) A separate organic material that emits color is used as a pattern.

In addition, a second electrode 115 forming a cathode is formed on an entire surface of the organic light emitting layer 113.

In this case, the second electrode 115 has a double layer structure, and a double layer structure in which a transparent conductive material is thickly deposited on a semitransparent metal film in which a thin metal material having a low work function is deposited.

Therefore, the light emitted from the organic light emitting layer 113 is driven by the top emission method emitted toward the second electrode 115.

When a predetermined voltage is applied to the first electrode 111 and the second electrode 115 according to the selected color signal, the flexible OLED 100 may inject holes and second electrodes 115 injected from the first electrode 111. Electrons provided from the organic light emitting layer 113 are transported to form an exciton, and when the exciton transitions from the excited state to the ground state, light is generated and emitted in the form of visible light.

At this time, the emitted light passes through the transparent second electrode 115 to the outside, so that the flexible OLED 100 implements an arbitrary image.

In addition, a protective film 130 in the form of a thin thin film is formed on the driving thin film transistor DTr and the organic light emitting diode E, and the flexible OLED 100 according to the first embodiment of the present invention is a protective film. Encapsulation is performed through 130.

In order to prevent external oxygen and moisture from penetrating into the flexible OLED 100, the protective film 130 is laminated with at least two inorganic protective films 130a and 130c, wherein two inorganic protective films ( It is preferable that the organic protective film 130b is interposed between 130a and 130c. The reason is that the inorganic protective films 130a and 130c are suitable for preventing the penetration of oxygen and moisture, and the organic protective film 130b serves to secure the impact resistance of the inorganic protective films 130a and 130c. .

Thus, the flexible OLED 100 according to the first embodiment of the present invention can be encapsulated through the protective film 130, so that the OLED 100 can be formed to a thin thickness compared to the case of encapsulation with glass. The overall thickness of the OLED 100 can be reduced.

In addition, the OLED 100 has a flexible characteristic, thereby implementing a flexible OLED that can maintain the display performance as it is, even if bent like paper.

Here, the substrate 101 is made of a flexible glass substrate or a plastic material having flexible characteristics so that the display performance can be maintained even when the flexible OLED 100 is bent like a paper. In this case, the substrate 101 has four edges. Is bent upward to have a bottom surface 101a and a side surface 101b to define the receiving area C therein.

Accordingly, the flexible OLED 100 of the present invention prevents penetration of external moisture and oxygen into the flexible OLED 100 in the storage area C defined by the bottom surface 101a and the side surface 101b of the substrate 101. The barrier layer 140 is formed.

As a result, the bezel area of the flexible OLED 100 is prevented from being widened by the barrier layer 140 formed of a multilayer.

In more detail, the flexible glass substrate or the substrate 101 made of a plastic material has a disadvantage in that external moisture or oxygen easily penetrates, and the external oxygen and moisture are transferred to the flexible OLED 100 through the substrate 101. ) Will penetrate inside.

As such, when oxygen and moisture are introduced into the flexible OLED 100, oxidation and corrosion of the electrode layer are generated while electroluminescence is performed, and in this case, the risk of current leakage and short circuiting increases, and pixel defects occur. As a result, there is a problem of reducing the lifetime of the display device itself.

 Therefore, in order to prevent such a problem, the barrier layer 140 is formed between the substrate 101 and the organic light emitting diode E, and oxygen and moisture are transferred through the barrier layer 140 to the organic light emitting diode E. It is to prevent contact with.

At this time, the barrier layer 140 is preferably composed of a plurality of layers in which at least one inorganic insulating material (110a, 110b, 110c, 110d) and at least one organic insulating material (120a, 120b, 120c) are alternately stacked. In the flexible OLED 100 according to the first embodiment of the present invention, the barrier layer 140 includes the first to fourth inorganic barrier layers 110a, 110b, 110c, and 110d and the first to third organic barrier layers 120a. , 120b, 120c).

Here, the first to fourth inorganic barrier layers 110a, 110b, 110c, and 110d serve to prevent the penetration of oxygen and moisture, and the first to third organic barrier layers 120a, 120b, and 120c are the first. To secure the impact resistance of the fourth inorganic barrier layer (110a, 110b, 110c, 110d).

The first to fourth inorganic barrier layers 110a, 110b, 110c, and 110d may be formed of silicon oxide (SiO 2), silicon nitride (SixNy), silicon oxynitride (SiON), aluminum oxide (AlOx), aluminum nitride (Alon), TIO, ZnO, and the like, and the first to third organic barrier layers 120a, 120b, and 120c may use a monomer or a polymer thin film. As monomers, acrylate monomers and phenylacetylene may be used. (phenylacetylene), diamine and dianhydride, siloxane, silane, parylene and the like may be used.

In addition, an olefin polymer (polyethylene, polypropylene), polyethylene terephthalate (PET), fluororesin, polysiloxane, or the like may be used as the polymer thin film.

Therefore, the flexible OLED 100 according to the first embodiment of the present invention may be formed of a flexible glass substrate or a plastic, which is easily penetrated by external moisture or oxygen, even though the barrier layer 140 is provided. Moisture and oxygen from the outside to prevent penetration into the flexible OLED (100).

Thus, due to the oxygen or moisture introduced into the flexible OLED 100, oxidation and corrosion of the electrode layer may be prevented from occurring, and thus the emission characteristics of the organic light emitting layer (113 of FIG. 1) are reduced, and the organic light emitting layer is prevented. The problem that the lifetime of (113 in FIG. 1) is shortened can be prevented.

In addition, current leakage and short circuits can be prevented from occurring, and pixel defects can be prevented from occurring. This prevents the problem of uneven brightness or image characteristics.

At this time, in the structure in which the organic barrier layers 120a, 120b, and 120c and the inorganic barrier layers 110a, 110b, 110c, and 110d are alternately stacked, moisture and water may pass through the sides of the organic barrier layers 120a, 120b, and 120c. In order to prevent oxygen from penetrating, it is preferable that the inorganic barrier layers 110a, 110b, 110c, and 110d have a structure completely covering the organic barrier layers 120a, 120b, and 120c.

Accordingly, the barrier layer 140 has the first inorganic barrier layer 110a at the storage area C including the bottom surface 101a and the side surfaces 101b of the substrate 101 and the bottom surface 101a and the side surfaces of the substrate 101. The first organic barrier layer 120a is formed along the inner surface of the substrate 101 and the first organic barrier layer 120a is formed on the first inorganic barrier layer 110a. As a result, the side and bottom surfaces are formed in a wrapped structure.

That is, the first inorganic barrier layer 110a is formed in the shape of the storage area C defined through the bottom surface 101a and the side surface 101b of the substrate 101, and is formed of the side surface and the bottom surface to define the storage area. The first organic barrier layer 120a is formed in a structure in which a bottom surface and a side surface of the first inorganic barrier layer 110a are wrapped.

The second inorganic barrier layer 110b is formed on the first organic barrier layer 120a and the upper portion of the first inorganic barrier layer 110a formed along the inner side of the side surface 101b of the substrate 101. The second organic barrier layer 120b is formed on the second inorganic barrier layer 110b.

At this time, the second organic barrier layer 120b is also formed in a structure in which side and bottom surfaces are surrounded by the second inorganic barrier layer 110b.

In addition, the third inorganic barrier layer 110c is also formed on the upper portion of the second organic barrier layer 120b and the second inorganic barrier layer 110b formed along the inner side of the side surface 101b of the substrate 101. The third organic barrier layer 120c is formed on the third inorganic barrier layer 110c such that the side and bottom surfaces thereof are surrounded by the third inorganic barrier layer 110c.

At this time, the first to third inorganic barrier layer (110a, 110b, 110c) is also formed on the upper side of the side 101b of the substrate 101, in this case, the third organic barrier layer 120c and the side of the substrate 101 It is preferable that the third inorganic barrier layer 110c formed on the upper portion of the 101b forms the same plane, and the fourth inorganic barrier layer is formed on the third organic barrier layer 120c and the third inorganic barrier layer 110c. 110d is further formed.

The driving thin film transistor DTr and the organic light emitting diode E of the flexible OLED 100 are formed on the fourth inorganic barrier layer 110d.

In this case, it can be seen that the bezel region B of the flexible OLED 100 according to the first embodiment of the present invention is narrower than the bezel region A of the flexible OLED 100 of FIGS. 1 and 2.

In detail, the barrier layer 140 is formed by alternately repeating the inorganic barrier layers 110a, 110b, 110c, and 110d and the organic barrier layers 120a, 120b, and 120c on the flat substrate 101. In the process, the inorganic barrier layers (110a, 110b, 110c, 110d) is not good step coverage, the organic barrier layers (120a, 120b, 120c) formed on the inorganic barrier layers (110a, 110b, 110c, 110d) In order to be formed on top of the inorganic barrier layers 110a, 110b, 110c, and 110d having good flatness, the inner portion of the organic barrier layers 120a, 120b, and 120c, which are located at the bottom, is positioned as much as A 'shown in FIG. It is formed so as to inject.

Accordingly, the driving thin film transistor DTr and the organic light emitting diode E formed on the barrier layer 140 are further recessed inward from the edge of the substrate 101, thereby effectively displaying an image. The region is formed smaller than the area of the substrate 101, and the inorganic barrier layers 110a, 110b, 110c, and 110d and the organic barrier layers 120a, 120b, and 120c are recessed inward from the edge of the substrate 101. As a result, the bezel area (A in FIG. 2), which is a non-light emitting area forming a step, is increased.

On the contrary, in the flexible OLED 100 according to the first embodiment of the present invention, the inorganic barrier layers 110a, 110b, 110c, and the storage region C are formed of the bottom surface 101a and the side surface 101b of the substrate 101. 110d) and the organic barrier layers 120a, 120b, and 120c are alternately stacked repeatedly, and inorganic barrier layers 110a, 110b, 110c, and 110d formed on the organic barrier layers 120a, 120b, and 120c. The organic barrier layers 120a, 120b, and 120c formed on the inorganic barrier layers 110a, 110b, 110c, and 110d are not formed along the steps of the organic barrier layers 120a, 120b, and 120c. The organic barrier layers 120a, 120b, and 120c which are positioned do not need to be recessed inward as much as the region A 'shown in FIG.

Through this, the bezel region B of the flexible OLED 100 according to the first embodiment of the present invention may be formed narrower than the bezel region A of the flexible OLED 100 of FIGS. 1 and 2.

Here, in the first embodiment of the present invention, the first to fourth inorganic barrier layers 110a, 110b, 110c, and 110d and the first to third organic barrier layers 120a, 120b, and 120c are alternately repeatedly stacked. Although the configuration for forming the layer 140 is illustrated and described, the barrier layer 140 may include at least one organic barrier layer 120a, 120b, 120c and at least one inorganic barrier layer 110a, 110b, 110c, 110d. ) Can be alternately laminated.

In the drawings and descriptions so far, the first to fourth inorganic barrier layers 110a, 110b, 110c, and 110d are also formed on the upper side of the side surface 101b of the substrate 101 or the side surface of the substrate 101. The height of 101b is further increased, so that the side surfaces 101b of the substrate 101 have the first to fourth inorganic barrier layers 110a, 110b, 110c and 110d and the first to third organic barrier layers 120a and 120b. , 120c) is also possible to surround all configurations.

- Second Embodiment -

5 is a schematic cross-sectional view of a flexible OLED according to a second exemplary embodiment of the present invention.

Meanwhile, in order to avoid duplicate descriptions, the same reference numerals are given to the same parts that play the same role as the above-described first embodiment, and only the characteristic contents to be described in the second embodiment will be described.

As shown, in the flexible OLED 100 according to the second embodiment of the present invention, a substrate 101 on which a driving thin film transistor DTr and an organic light emitting diode E is formed is encapsulated by a protective film 130. It is encapsulated.

In this case, a barrier layer 140 is formed on the substrate 101 to prevent penetration of external moisture and oxygen into the flexible OLED 100, and the edge of the barrier layer 140 is encapsulated by the partition wall 150. do.

In more detail, the flexible glass substrate or the substrate 101 made of a plastic material has a disadvantage in that external moisture or oxygen easily penetrates, and the external oxygen and moisture are transferred to the flexible OLED 100 through the substrate 101. ) Will penetrate inside.

As such, when oxygen and moisture are introduced into the flexible OLED 100, oxidation and corrosion of the electrode layer are generated while electroluminescence is performed, and in this case, the risk of current leakage and short circuiting increases, and pixel defects occur. As a result, there is a problem of reducing the lifetime of the display device itself.

 Therefore, in order to prevent such a problem, the barrier layer 140 is formed between the substrate 101 and the organic light emitting diode E, and oxygen and moisture are transferred through the barrier layer 140 to the organic light emitting diode E. It is to prevent contact with.

At this time, the barrier layer 140 is preferably composed of a plurality of layers in which at least one inorganic insulating material (110a, 110b, 110c, 110d) and at least one organic insulating material (120a, 120b, 120c) are alternately stacked. In the flexible OLED 100 according to the second embodiment of the present invention, the barrier layer 140 may include first to fourth inorganic barrier layers 110a, 110b, 110c, and 110d and first to third organic barrier layers 120a. , 120b, 120c).

Here, the first to fourth inorganic barrier layers 110a, 110b, 110c, and 110d serve to prevent the penetration of oxygen and moisture, and the first to third organic barrier layers 120a, 120b, and 120c are the first. It serves to secure the impact resistance of the fourth inorganic barrier layer (110a, 110b, 110c, 110d).

The first to fourth inorganic barrier layers 110a, 110b, 110c, and 110d may be formed of silicon oxide (SiO 2), silicon nitride (SixNy), silicon oxynitride (SiON), aluminum oxide (AlOx), aluminum nitride (Alon), TIO, ZnO, and the like, and the first to third organic barrier layers 120a, 120b, and 120c may use a monomer or a polymer thin film. As monomers, acrylate monomers and phenylacetylene may be used. (phenylacetylene), diamine and dianhydride, siloxane, silane, parylene and the like may be used.

In addition, an olefin polymer (polyethylene, polypropylene), polyethylene terephthalate (PET), fluororesin, polysiloxane, or the like may be used as the polymer thin film.

Therefore, the flexible OLED 100 according to the second exemplary embodiment of the present invention may be formed of a flexible glass substrate or a plastic, which easily penetrates external moisture or oxygen, through the barrier layer 140. Moisture and oxygen from the outside to prevent penetration into the flexible OLED (100).

Thus, due to the oxygen or moisture introduced into the flexible OLED 100, oxidation and corrosion of the electrode layer may be prevented from occurring, and thus the emission characteristics of the organic light emitting layer (113 of FIG. 1) are reduced, and the organic light emitting layer is prevented. The problem that the lifetime of (113 in FIG. 1) is shortened can be prevented.

In addition, current leakage and short circuits can be prevented from occurring, and pixel defects can be prevented from occurring. This prevents the problem of uneven brightness or image characteristics.

At this time, in the structure in which the organic barrier layers 120a, 120b, and 120c and the inorganic barrier layers 110a, 110b, 110c, and 110d are alternately stacked, moisture and water may pass through the sides of the organic barrier layers 120a, 120b, and 120c. In order to prevent oxygen from penetrating, it is preferable that the inorganic barrier layers 110a, 110b, 110c, and 110d have a structure completely covering the organic barrier layers 120a, 120b, and 120c.

In particular, the flexible OLED 100 according to the second embodiment of the present invention encapsulates the edge of the barrier layer 140 through the partition wall 150, thereby more reliably preventing external moisture and oxygen from penetrating into the multilayer. The barrier layer 140 is formed to prevent the bezel region B ′ of the flexible OLED 100 from being widened.

That is, the first inorganic barrier layer 110a is formed on the substrate 101, and the partition wall 150 is formed around the edge of the substrate 101 on the first inorganic barrier layer 110a.

Thus, the receiving region D of the barrier layer 140 by the partition wall 150 is defined on the substrate 101.

Accordingly, the first organic barrier layer 120a is formed on the first inorganic barrier layer 110a in the partition 150 on the substrate 101. The bottom surface of the first organic barrier layer 120a is the first inorganic barrier. The layer 110a is wrapped, and the side surface of the first organic barrier layer 120a forms a structure in which the partition wall 150 is wrapped.

In this case, the partition wall 150 may be made of an organic material or a metal and an inorganic material, and the organic material may be a thermosetting resin or a UV curable resin.

The inorganic material may be made of silicon oxide (SiO 2), silicon nitride (SixNy), silicon oxynitride (SiON), aluminum oxide (AlOx), aluminum nitride (Alon), TIO, ZnO, or the like, or purified glass. It may be a material having fine particles.

At this time, the material having the purified glass fine particles, K2O, Fe2O3, Sb2O3, ZnO, P2O5, V2O5, TiO2, Al2O3, WO3, SnO, PbO, MgO, CaO, BaO, Li2O, Na2O, B2O3, TeO2, SiO2, Ru2O It may include at least one selected from the group consisting of, Rb2O, Rh2O, CuO and Bi2O3.

A second inorganic barrier layer 110b is formed on the first organic barrier layer 120a, and the second inorganic barrier layer 110b forms an upper surface of the first organic barrier layer 120a and an inner surface of the partition wall 150. Formed accordingly.

In addition, a second organic barrier layer 120b is formed on the second inorganic barrier layer 110b, and the second organic barrier layer 120b has a structure in which side and bottom surfaces thereof are surrounded by the second inorganic barrier layer 110b. Is formed.

In addition, a third inorganic barrier layer 110c is formed on the upper portion of the second organic barrier layer 120b and the second inorganic barrier layer 110b formed along the inner surface of the partition wall 150, and the third inorganic barrier. The third organic barrier layer 120c is formed on the layer 110c.

In this case, the third organic barrier layer 120c is also formed in a structure in which side and bottom surfaces are surrounded by the third inorganic barrier layer 110c.

At this time, the second and third inorganic barrier layer (110b, 110c) is also formed on the upper part of the partition wall 150, in this case, the third inorganic barrier layer formed on the third organic barrier layer (120c) and the partition wall 150. The layer 110c preferably forms the same plane, and the fourth inorganic barrier layer 110d is further formed on the third organic barrier layer 120c and the third inorganic barrier layer 110c.

The driving thin film transistor DTr and the organic light emitting diode E of the flexible OLED 100 are formed on the fourth inorganic barrier layer 110d.

In this case, the bezel region B ′ of the flexible OLED 100 according to the second exemplary embodiment of the present invention may be narrower than the bezel region A of FIGS. 1 and 2.

In detail, the barrier layer 140 is formed by alternately repeating the inorganic barrier layers 110a, 110b, 110c, and 110d and the organic barrier layers 120a, 120b, and 120c on the flat substrate 101. In the process, the inorganic barrier layers (110a, 110b, 110c, 110d) is not good step coverage, the organic barrier layers (120a, 120b, 120c) formed on the inorganic barrier layers (110a, 110b, 110c, 110d) In order to be formed on top of the inorganic barrier layers 110a, 110b, 110c, and 110d having good flatness, the inner portion of the organic barrier layers 120a, 120b, and 120c, which are located at the bottom, is positioned as much as A 'shown in FIG. It is formed so as to inject.

Accordingly, the driving thin film transistor DTr and the organic light emitting diode E formed on the barrier layer 140 are further recessed inward from the edge of the substrate 101, thereby effectively displaying an image. The region is formed smaller than the area of the substrate 101, and the inorganic barrier layers 110a, 110b, 110c, and 110d and the organic barrier layers 120a, 120b, and 120c are recessed inward from the edge of the substrate 101. As a result, the bezel area (A in FIG. 2), which is a non-light emitting area forming a step, is increased.

On the contrary, in the flexible OLED 100 according to the second embodiment of the present invention, the inorganic barrier layers 110a and 110b may be formed in the storage area D defined by the partition wall 150 formed along the edge of the substrate 101. 110c and 110d and the organic barrier layers 120a, 120b, and 120c are alternately stacked, and the inorganic barrier layers 110a, 110b, 110c, which are formed on the organic barrier layers 120a, 120b, and 120c. 110d) is not formed along the steps of the organic barrier layers 120a, 120b, and 120c, so that the organic barrier layers 120a, 120b, and 120c are formed on the inorganic barrier layers 110a, 110b, 110c, and 110d. It is not necessary to be recessed and formed as much as the area of A 'shown in FIG. 2 from the ends of the organic barrier layers 120a, 120b, and 120c located below.

Through this, the bezel region B ′ of the flexible OLED 100 according to the second exemplary embodiment of the present invention may be narrower than the bezel region A of the flexible OLED 100 of FIGS. 1 and 2. .

Here, in the second embodiment of the present invention, the first to fourth inorganic barrier layers 110a, 110b, 110c, and 110d and the first to third organic barrier layers 120a, 120b, and 120c are alternately stacked, and the barriers are alternately stacked. Although the configuration for forming the layer 140 is illustrated and described, the barrier layer 140 may include at least one organic barrier layer 120a, 120b, 120c and at least one inorganic barrier layer 110a, 110b, 110c, 110d. ) Can be alternately laminated.

In the drawings and descriptions so far, the first to fourth inorganic barrier layers 110a, 110b, 110c, and 110d are formed on the partition wall 150, or the height of the partition wall 150 is further increased. The partition wall 150 may also be configured to cover all of the first to fourth inorganic barrier layers 110a, 110b, 110c and 110d and the first to third organic barrier layers 120a, 120b and 120c.

In addition, in the second embodiment of the present invention, the configuration in which the partition wall 150 is formed on the first inorganic barrier layer 110a has been described, but the partition wall 150 is formed on the substrate 101 and the first inorganic layer is formed. It is also possible for the barrier layer 110a to be formed along the bottom surface of the substrate 101 and the inner surface of the partition wall 150.

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.

100: OLED, 101: substrate
110a, 110b, 110c, 110d: inorganic barrier layer
111: first electrode, 113: organic light emitting layer, 115: second electrode
120a, 120b, 120c: organic barrier layer, 130a, 130b, 130c: protective film
DTr: driving thin film transistor, P: pixel area

Claims (13)

A substrate comprising a bottom surface and four edges of the bottom surface bent upwardly to define a receiving area therein;
A lower encapsulation layer formed by alternately stacking at least one organic film and at least one inorganic film inside the storage area;
A driving thin film transistor formed on the lower encapsulation layer and an organic light emitting diode connected to the driving thin film transistor, the organic light emitting diode connected to the driving thin film transistor;
An upper encapsulation layer covering the driving thin film transistor and the organic light emitting diode
Flexible organic electroluminescent device comprising a.
A substrate;
A partition wall formed around four edges of the substrate;
A lower encapsulation layer formed by alternately stacking at least one organic film and at least one inorganic film inside the partition wall;
A driving thin film transistor and an organic light emitting diode formed on the lower encapsulation layer;
An upper encapsulation layer covering the driving thin film transistor and the organic light emitting diode
Flexible organic electroluminescent device comprising a.
The method according to any one of claims 1 and 2,
The inorganic layer is a flexible organic electroluminescent device having a structure surrounding the organic film.
The method of claim 1,
The inorganic layer is formed along the bottom surface of the substrate and the side surface of the substrate or the inner surface of the partition wall, the organic film is formed on the inorganic film corresponding to the bottom surface of the substrate.
The method of claim 2,
The inorganic film is formed along the inner surface of the partition wall, the organic film is formed on the inorganic film corresponding to the bottom surface of the substrate.
The method of claim 1,
The inorganic layer may include first to fourth inorganic layers, the organic layer may include first to third organic layers, and the first inorganic layer may be formed along the inner surface of the bottom and side surfaces of the substrate. A first organic layer is positioned to surround side surfaces and a bottom surface of the first inorganic layer, and the second inorganic layer is formed along an inner surface of an upper side of the first organic layer and a side surface of the substrate. A side surface and a bottom surface are surrounded by a second inorganic layer, and the third inorganic layer is formed along the inner surface of the upper side of the second organic layer and the side surface of the substrate, and the third organic layer is formed on the third inorganic layer. A flexible organic electroluminescent device having a side surface and a bottom surface wrapped therebetween and having a fourth inorganic layer positioned on the third organic layer and the third inorganic layer.
The method of claim 2,
The inorganic layer is formed of first to fourth inorganic layers, the organic layer is formed of first to third organic layers, the first inorganic layer is formed on the substrate, and the first organic layer is formed inside the partition wall. And a side surface of the first inorganic layer is surrounded by a lower surface and the partition wall, and the second inorganic layer is formed along an upper surface of the first organic layer and an inner surface of the partition wall. Side and bottom surfaces are surrounded by an inorganic film, and the third inorganic film is formed along an upper surface of the second organic film and an inner surface of the partition wall, and the third organic film is formed by the third inorganic film. The organic light emitting device of claim 4, wherein a fourth inorganic layer is positioned on the third organic layer and the third inorganic layer.
The method of claim 5, wherein
The first to fourth inorganic layers are formed on an upper side of the substrate, and the third organic layer and the third organic layer formed on the upper side of the substrate are coplanar.
The method according to claim 6,
The first to fourth inorganic layers are formed on the barrier ribs, and the third inorganic layer and the third organic membrane on the barrier ribs are coplanar.
The method according to any one of claims 1 and 2,
The inorganic layer is made of one selected from silicon oxide (SiO 2), silicon nitride (SixNy), silicon oxynitride (SiON), aluminum oxide (AlOx), aluminum nitride (Alon), TIO, and ZnO, and the organic layer is an acrylate monomer. (acrylate monomer), phenylacetylene, diamine and dianhydride, siloxane, silane, parylene, olefin polymer (polyethylene, polypropylene), polyethylene Flexible organic electroluminescent device comprising one selected from terephthalate (PET), fluororesin, and polysiloxane.
The method according to any one of claims 1 and 2,
The substrate is a flexible organic electroluminescent device comprising one selected from a flexible glass substrate or plastic.
The method according to any one of claims 1 and 2,
The driving thin film transistor includes a semiconductor layer, a gate electrode, a source, and a drain electrode.
The method of claim 12,
The organic light emitting diode is a flexible organic light emitting device comprising a first electrode, an organic light emitting layer and a second electrode connected to the driving thin film transistor.

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