KR20170050847A - Organic light emitting diode display - Google Patents

Abstract

There is provided an organic light emitting diode display having an encapsulation layer for encapsulating an organic light emitting diode according to an embodiment of the present invention. The encapsulation layer includes an inorganic layer and the inorganic layer includes a composite functional material capable of absorbing oxygen and moisture while exhibiting a light scattering effect, thereby improving the reliability of the encapsulation layer and improving the light efficiency of the organic light emitting device.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an organic light-

The present invention relates to an organic light emitting diode (OLED) display, and more particularly, to an organic light emitting diode (OLED) display device including a multifunctional material to improve the reliability of a sealing layer and improve the efficiency of light emitted from the organic light emitting diode .

The organic light emitting diode (OLED) is a self-emissive type display device, and unlike a liquid crystal display (LCD), a separate light source is not required, so that it can be manufactured in a light and thin shape. Further, the organic light emitting display device is not only advantageous from the viewpoint of power consumption by low voltage driving, but also excellent in color implementation, response speed, viewing angle, and contrast ratio (CR), and is being studied as a next generation display.

In the organic light emitting display, an organic light emitting layer including an organic material is disposed on a pixel electrode, and a common electrode is disposed on the organic light emitting layer.

The organic light emitting element emits light by supplying each of the holes and electrons from the pixel electrode and the common electrode, respectively. However, the organic material contained in the organic light emitting layer of the organic light emitting device is vulnerable to oxygen and moisture, so that defects such as a dark spot may occur when oxygen and moisture permeate.

As described above, the organic light emitting display device is extremely vulnerable to oxygen, moisture, and the like because organic materials are used as the light emitting layer. Accordingly, various techniques for sealing the organic light emitting device have been used to minimize penetration of oxygen, water, etc. from the outside into the organic light emitting layer.

As a sealing technique for sealing an organic light emitting device, a sealing film covering a front surface of a substrate on which an organic light emitting device is disposed and a method of alternately depositing an inorganic substance and an organic substance on the entire surface of the substrate on which the organic light emitting device is disposed are mainly used have.

The inorganic encapsulating membrane using inorganic materials can not maximize the sealing performance, and inorganic and organic materials are alternately deposited to enhance the performance of the encapsulating membrane.

The thin film layer used as a protective layer for protecting the organic light emitting device from moisture and oxygen is formed of a material such as silicon nitride (SiNx), silicon oxide (SiOx), silicon oxynitride SiON, aluminum oxide (AlOx), and the like. PECVD and ALD are mainly used for the deposition method.

In a thin film encapsulation technique in which an inorganic material and an organic material are alternately laminated so as to seal the organic light emitting element, the inorganic material is easy to secure high barrier property but is not flexible in itself and cracks and the like may be generated. In order to compensate for the disadvantages of inorganic materials, a technique of alternately depositing flexible organic materials and inorganic materials relative to inorganic materials and arranging the sealing layer is used.

In the alternately laminated structure of an organic material and an inorganic material for sealing the organic light emitting element, the inorganic material is vulnerable to impact and warpage, and is likely to crack. In addition, the manufacturing cost due to the step of alternately stacking the organic material and the inorganic material is also increased, and the thickness of the organic light emitting display device is increased and the efficiency of light emitted from the organic light emitting device is decreased. Accordingly, the inventors of the present invention invented a new structure of an organic light emitting display device which can improve the reliability of the inorganic material layer included in the sealing layer and improve the light efficiency with respect to the light emitted from the organic light emitting device.

SUMMARY OF THE INVENTION The present invention provides an organic light emitting diode (OLED) display device capable of maximizing an encapsulation function of an inorganic layer used in an encapsulation layer.

SUMMARY OF THE INVENTION The present invention provides an organic light emitting display capable of improving the efficiency of light emitted from an organic light emitting diode.

The solutions according to one embodiment of the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

There is provided an organic light emitting diode display having an encapsulation layer for encapsulating an organic light emitting diode according to an embodiment of the present invention. The sealing layer is disposed on the light emitting side of the organic light emitting element and is arranged to cover the organic light emitting element. In addition, the sealing layer may include a multi-functional material that adsorbs oxygen and moisture, thereby scattering light emitted from the organic light emitting device and maximizing the efficiency of light emitted from the organic light emitting device due to the light extraction effect. The encapsulant layer can minimize the cracks that can be generated in the encapsulant layer even in a shocked or flexible environment by including a multifunctional material.

According to the embodiment of the present invention, it is possible to improve the reliability of the sealing layer and to improve the light efficiency by the light scattering effect by the complex functional material by providing the sealing layer including the composite functional material capable of adsorbing oxygen and moisture It is effective.

Further, by using a sealing layer containing a composite functional material, the reliability of the inorganic material layer included in the sealing layer can be improved, and the sealing layer can be realized with a simple structure such as a single-layer structure, thereby reducing manufacturing cost.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description.

The scope of the claims is not limited by the matters described in the contents of the invention, as the contents of the invention described in the problems, the solutions to the problems and the effects to be solved do not specify essential features of the claims.

FIG. 1 is a schematic cross-sectional view illustrating an organic light emitting display in which an encapsulating layer having a multi-functional material according to an embodiment of the present invention is disposed.
FIG. 1B is a schematic cross-sectional view illustrating an organic light emitting display device having improved light efficiency with a multi-functional material in a sealing layer according to an exemplary embodiment of the present invention.
2 is a schematic cross-sectional view illustrating an organic light emitting display device having a multilayer encapsulating layer having a multi-functional material according to an exemplary embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, and the like disclosed in the drawings for describing the embodiments of the present invention are illustrative, and thus the present invention is not limited thereto. Like reference numerals refer to like elements throughout the specification. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Where the terms "comprises", "having", "done", and the like are used in this specification, other portions may be added unless "only" is used. Unless the context clearly dictates otherwise, including the plural unless the context clearly dictates otherwise.

In interpreting the constituent elements, it is construed to include the error range even if there is no separate description.

In the case of a description of the positional relationship, for example, if the positional relationship between two parts is described as 'on', 'on top', 'under', and 'next to' Or " direct " is not used, one or more other portions may be located between the two portions.

The first, second, etc. are used to describe various components, but these components are not limited by these terms. These terms are used only to distinguish one component from another. Therefore, the first component mentioned below may be the second component within the technical spirit of the present invention.

It is to be understood that each of the features of the various embodiments of the present invention may be combined or combined with each other, partially or wholly, technically various interlocking and driving, and that the embodiments may be practiced independently of each other, It is possible.

Hereinafter, various configurations of the organic light emitting diode display capable of minimizing penetration of oxygen into the organic light emitting layer used for forming the oxide layer according to an embodiment of the present invention will be described.

According to the structure of the organic light emitting diode display, the percent OTR of the lower inorganic layer is lower than the percentage OTR of the upper inorganic layer.

According to the structure of the organic light emitting diode display, the lower inorganic layer has a low transitivity (OTR) of 1.5 cm ² / m ² / day or less.

Various embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic cross-sectional view illustrating an organic light emitting display in which an encapsulating layer having a multi-functional material according to an embodiment of the present invention is disposed.

1, the OLED display 100 includes a substrate 110, a driving device 120, a flat layer 130, a bank layer 140, an organic light emitting diode 150, an encapsulation layer 160, And a multi-functional material 170.

The substrate 110 is a substrate for supporting various components of the organic light emitting diode display 100. The substrate 110 may be a glass substrate or a polyimide-based flexible substrate. The substrate 110 may include a barrier layer to minimize penetration of moisture and oxygen.

The driving element 120 is an element for driving the organic light emitting element 150, and may be a thin film transistor. For example, the driving element 120 may be an oxide thin film transistor using an oxide semiconductor or a thin film transistor including polysilicon. In FIG. 1, the driving element 120 is shown as a square, but the driving element 120 may include a gate electrode, an active electrode, and a source / drain electrode. In addition, the driving element 120 may include a plurality of thin film transistors, or may include capacitors in addition to the thin film transistors.

Though the oxide thin film transistor requires a higher driving voltage than the polysilicon transistor, the oxide thin film transistor has a small number of steps and a low production cost. The oxide thin film transistor has excellent off current characteristics and can be driven at a low frequency of 60 Hz or less.

A flat layer 130 for disposing the organic light emitting element 150 is disposed on the driving element 120. The planarization layer 130 may be made of polyimide, and may have a single layer structure or a multi-layer structure. The flat layer 130 also opens a part of the driving element 120 to electrically connect the driving element 120 and the organic light emitting element 150.

The organic light emitting element 150 is disposed on the flat film. The organic light emitting diode 150 includes a pixel electrode 151, an organic light emitting layer 152, and a common electrode 153. The pixel electrode 151 of the organic light emitting diode 150 is electrically connected to the driving element 120 through the connection electrode 121.

The pixel electrode 151 and the connection electrode 121 may be formed of substantially the same material and the connection electrode 121 may be disposed at the same time in the process of disposing the pixel electrode 151. That is, in the process of forming the pixel electrode 151 in a state where the flat layer 130 partially opens the driving device 120, the connection electrode 121 may be formed of the same material at the same time as the pixel electrode 151 have.

The organic light emitting layer 152 emits light by holes and electrons injected from the pixel electrode 151 and the common electrode 153, respectively. For smooth excition formation, the organic emission layer 152 may include a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer. In addition, the organic light emitting layer 152 may have a structure including a plurality of organic light emitting layers.

Each of the pixel electrode 151 and the common electrode 153 may be an anode or a cathode. The pixel electrode 151 and the common electrode 153 may be transparent electrodes capable of transmitting light emitted from the organic light emitting layer 152. Alternatively, one of the pixel electrode 151 and the common electrode 153 may be a reflective electrode in order to induce light emission in one direction. The organic light emitting diode display 100 according to an embodiment of the present invention includes a top emission type organic light emitting display device 100 for passing light emitted from the organic light emitting layer 152 over the organic light emitting display device 100, The common electrode 153 may be made of a transparent conductive material or may be an electrode having a very thin metal material. The pixel electrode 151 may be formed of a transparent conductive material and a reflective layer may be further disposed under the pixel electrode 151 to reflect light emitted from the organic light emitting layer 152 upward. Alternatively, the pixel electrode 151 itself may be a transparent conductive layer on the reflective layer and the reflective layer.

A bank layer 190 is disposed around the pixel electrode 151 to separate the pixels.

The sealing layer 160 is disposed on the organic light emitting device 150 to minimize penetration of oxygen and moisture into the organic light emitting device 150 and the adhesive layer Can be further arranged.

The sealing layer 160 may be a sealing layer made of an inorganic material and may be made of a material selected from silicon nitride (SiNx), silicon oxynitride (SiOxNy), and aluminum oxide (AlOx). Minerals have a disadvantage in that they have a high ability to block oxygen and moisture, but they can crack due to physical impact or warping. Thus, the sealing layer 160 is disposed including the multi-functional material 170.

The composite functional material 170 may be included in the sealing layer 160 in the form of fine particles to prevent or suppress the sealing layer 160 from being cracked due to stress caused by impact and warping.

In addition, when the multi-functional material 170 is included in the sealing layer 160 in the form of fine particles, light emitted from the organic light-emitting device 150 may be reflected and / or scattered by the particles of the multi-functional material 170 , So that light is scattered by the complex-function material 170 and a light extracting effect can be generated.

The multi-functional material 170 may include fine particles (first particles) that increase the rigidity of the sealing layer 160 and perform a light scattering function to improve the light efficiency due to the light extraction effect. The first particle can be at least one selected from the group consisting of silicon, silica, glass, titanium oxide, magnesium fluoride, zirconium oxide, alumina, cerium oxide, hafnium oxide, niobium pentoxide, tantalum pentoxide, indium oxide, tin oxide, indium tin oxide, , Calcium carbonate, barium sulfate, silicon nitride and aluminum nitride can be used.

In addition, the multi-functional material 170 included in the sealing layer 160 may include a second particle that adsorbs oxygen and moisture. For example, the second particle of multifunctional material 170 may be selected from the group consisting of CaO powder, metal oxide, organometallic complex, metal sulfate, metal halide, metal perchlorate, metal, P2O5, molecular sieve, a material selected from silica gel, barium oxide (BaO), strontium oxide (SrO), alkylaluminum alkoxide (RAIOR '), magnesium oxide (MgO), barium Ba and calcium (Ca).

The multi-functional material 170 included in the sealing layer 160 may include only the first particles, only the second particles, or the first particles and the second particles may be mixed. Further, the composite functional material 170 may further comprise additional particles in addition to the first and second particles. That is, at least the first particle and the second particle may be mixed with the multi-functional material 170. [

The multi-functional material 170 may be disposed on the organic light-emitting device 150 in a spraying manner and, when the inorganic material is disposed, the encapsulating layer 160 including the multi-functional material 170 may be disposed.

Generally, the sealing layer is disposed in a multi-layer structure including an inorganic material layer made of an inorganic material and an organic material layer made of an organic material so as to block the penetration of oxygen and a part by a crack or the like which may occur in the inorganic material. The sealing layer 160 of the organic light emitting diode display 100 according to the embodiment of the present invention includes the complex functional material 170 to improve the reliability and prevent the oxygen and moisture Can be effectively blocked.

That is, the multi-functional material 170 included in the sealing layer 160 adsorbs oxygen and moisture while forming the reliability of the sealing layer 160, scatters light emitted from the organic light emitting device 150, The light efficiency of the device 100 can be improved.

FIG. 1B is a schematic cross-sectional view illustrating an organic light emitting display device having improved light efficiency with a multi-functional material in a sealing layer according to an exemplary embodiment of the present invention.

The description will be made with reference to FIG. 1B, but repeated or substantially the same constitution will be omitted.

The sealing layer 160 is disposed including the multi-functional material 170.

The composite functional material 170 is sprayed and disposed on the organic light emitting element 150 and the sealing layer 160 is disposed by the ALD process or the CVD process to form the composite functional material 170, A convex portion 180 according to the multifunctional material 170 is disposed on the upper surface of the sealing layer 160. [

The height of the convex portion 180 may vary depending on the size of the multi-functional material 170 and the height of the sealing layer 160. A plurality of convex portions 180 are disposed on the sealing layer 160 by the composite functional material 170 made of fine particles and the convex portions 180 are disposed on the organic light emitting element 160, The light extraction efficiency of the light emitted from the light source 160 can be improved.

By including the composite functional material 170 in the sealing layer 160, lifetime reliability of the organic light emitting diode display 100 can be improved and the light efficiency can be maximized.

2 is a schematic cross-sectional view illustrating an organic light emitting display device having a multilayer encapsulating layer having a multi-functional material according to an exemplary embodiment of the present invention.

2, the OLED display 200 includes a substrate 210, a driving element 220, a flat layer 230, a bank layer 240, an organic light emitting diode 250, and a complex functional material 270a, 270b are disposed.

Hereinafter, repeated or substantially redundant configurations will be omitted.

At least one inorganic layer 260a and at least one organic layer 260b are alternately stacked to prevent the penetration of oxygen and moisture, and the sealing layer 260 is disposed.

A layer for preventing penetration of oxygen and moisture is disposed in a plurality of inorganic layers 260a as an inorganic layer 260a and an organic layer 260b is disposed between the inorganic layers 260a because the inorganic layer 260a is likely to be cracked.

The inorganic layer 260a may be disposed to include the multi-functional materials 270a and 270b to improve light extraction efficiency by inducing light scattering by the multi-functional materials 270a and 270b. In addition, the reliability of the inorganic layer 260a can be improved, and the occurrence of cracks can be minimized.

The multi-functional materials 270a and 270b may be fine particles composed of two materials so as to absorb oxygen and moisture while exhibiting a light scattering effect.

For example, the multi-functional materials 270a and 270b may be formed of a material selected from the group consisting of CaO powder, metal oxide, organometallic complex, metal sulfate, metal halide, metal perchlorate, metal, P2O5, molecular sieve, Oxygen and moisture composed of a material selected from the group consisting of silica gel, barium oxide (BaO), strontium oxide (SrO), alkyl aluminum alkoxide (RAIOR '), magnesium oxide (MgO), barium (Ba) The method of claim 1, wherein the fine particles that can be absorbed are selected from the group consisting of silicon, silica, glass, titanium oxide, magnesium fluoride, zirconium oxide, alumina, cerium oxide, hafnium oxide, niobium pentoxide, tantalum pentoxide, indium oxide, tin oxide, , A mixture of fine particles capable of producing a light scattering effect, which is made of a material selected from the group consisting of sulfur zinc, calcium carbonate, barium sulfate, silicon nitride and aluminum nitride.

Two kinds of materials may be mixed in the inorganic layer 260a or the composite functional materials 270a and 270b having different functions may be disposed in the different inorganic layers 260a.

In the case where the composite functional materials 270a and 270b having different properties are disposed in different inorganic layers 260a, the inorganic layer 260a capable of minimizing penetration of oxygen and hydrogen due to cracking and the light efficiency through light scattering The encapsulating layer 260 including the inorganic layer 260a for enhancing has a complex function.

The lowermost inorganic layer 260a of the sealing layer 260 is provided with the convex portion 280a by the multifunctional material 270a and the convex portion 280a is formed by the light extraction of the display device including the MLA The same light extracting effect as the effect is obtained.

An organic material layer 260b is disposed on the inorganic material layer 260a having the convex portion 280a. The organic material layer 260b is formed such that the convex portion 280b is disposed along the convex portion 280a of the inorganic layer 260a and the composite functional material 270b disposed on the convex portion 280a The composite functional materials 270a and 270b disposed between the convex portions 280b and disposed on the different inorganic layers 260a are arranged to be offset from each other and finally the upper surface of the sealing layer 260 is substantially It becomes flat.

The organic light emitting diode display 200 can maximize the light efficiency by the light extracting effect by the composite functional materials 270a and 270b and the convex portions 280a and 280b arranged alternately.

A display device according to an embodiment of the present invention can be described as follows.

In an organic light emitting display device having an encapsulating layer for encapsulating an organic light emitting diode, the encapsulation layer is located on the light emitting side of the organic light emitting diode, performs light extraction on light emitted from the organic light emitting diode, minimizes penetration of oxygen and moisture ≪ / RTI >

The multifunctional material may be mixed with at least a first particle and a second particle.

The first particle may be implemented to perform a light scattering function.

The first particle can be at least one selected from the group consisting of silicon, silica, glass, titanium oxide, magnesium fluoride, zirconium oxide, alumina, cerium oxide, hafnium oxide, niobium pentoxide, tantalum pentoxide, indium oxide, tin oxide, indium tin oxide, , Calcium carbonate, barium sulfate, silicon nitride, and aluminum nitride.

The second particle may be configured to adsorb oxygen and moisture.

The second particles may be selected from the group consisting of calcium oxide powder, metal oxides, organometallic complexes, metal sulfates, metal halides, metal perchlorates, metals, phosphorus pentoxide, molecular sieves, silica gels, barium oxides, strontium oxides, alkylaluminum alkoxides, magnesium oxides, ≪ / RTI >

The second particles may be made of a material having a different light transmittance from that of the inorganic layer constituting the sealing layer in order to obtain a light extracting effect.

The upper surface of the sealing layer may include convex portions configured to maximize the light extraction effect of the organic light emitting device.

The projections can correspond to the positions of the particles within the composite functional material.

The encapsulating layer is an inorganic layer made of an inorganic material and may be a single layer.

The encapsulation layer may comprise a material selected from silicon nitride, silicon oxynitride and aluminum oxide.

The sealing layer may be arranged to cover the multi-functional particles.

The encapsulating layer may comprise at least two layers of inorganic material.

Each of the inorganic layers of the two layers includes a composite-function material, and the composite-function materials contained in each of the inorganic layers of the two layers may be arranged to be substantially staggered with respect to each other.

The top surface of the encapsulant layer may be substantially planarized.

Although the embodiments of the present invention have been described in detail with reference to the accompanying drawings, it is to be understood that the present invention is not limited to those embodiments and various changes and modifications may be made without departing from the scope of the present invention. . Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. Therefore, it should be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of protection of the present invention should be construed according to the claims, and all technical ideas within the scope of equivalents should be interpreted as being included in the scope of the present invention.

100, 200: organic light emitting display
110, 210: substrate
120, 220: Driving element
130, 230: flat layer
140, 240: bank layer
150, 250: Organic light emitting device
160, 260: sealing layer
170, 270: Multifunctional material
180, 280: convex portion

Claims (15)

An organic light emitting diode display having an encapsulation layer for encapsulating an organic light emitting diode,
Wherein the sealing layer is on the light emitting side of the organic light emitting element,
And an organic light emitting diode (OLED). The organic light emitting diode display of claim 1, wherein the organic light emitting diode (OLED) includes a light emitting diode (OLED). The method according to claim 1,
Wherein the multi-functional material is a mixture of at least a first particle and a second particle. 3. The method of claim 2,
Wherein the first particle is implemented to perform a light scattering function. The method of claim 3,
Wherein the first particles are selected from the group consisting of silicon, silica, glass, titanium oxide, magnesium fluoride, zirconium oxide, alumina, cerium oxide, hafnium oxide, niobium pentoxide, tantalum pentoxide, indium oxide, tin oxide, indium tin oxide, Zinc, calcium carbonate, barium sulfate, silicon nitride, and aluminum nitride. 3. The method of claim 2,
Wherein the second particle is configured to adsorb oxygen and moisture. 6. The method of claim 5,
Wherein the second particles are selected from the group consisting of calcium oxide powder, metal oxides, organometallic complexes, metal sulfates, metal halides, metal perchlorates, metals, phosphorus pentoxide, molecular sieves, silica gels, barium oxides, strontium oxides, alkylaluminum alkoxides, magnesium oxides, Calcium, and combinations thereof. 6. The method of claim 5,
Wherein the second particles are made of a material having a different light transmittance from an inorganic material layer constituting the sealing layer to obtain a light extracting effect. The method according to claim 1,
Wherein an upper surface of the sealing layer includes a convex portion configured to maximize a light extracting effect of the organic light emitting element. 9. The method of claim 8,
Wherein the convex portion corresponds to a position of particles inside the multi-functional material. The method according to claim 1,
Wherein the sealing layer is an inorganic layer made of an inorganic material and is a single layer. 11. The method of claim 10,
Wherein the sealing layer comprises a material selected from silicon nitride, silicon oxynitride and aluminum oxide. The method according to claim 1,
And the sealing layer is arranged to cover the multi-functional particles. The method according to claim 1,
Wherein the sealing layer comprises at least two layers of inorganic layers. 14. The method of claim 13,
Wherein each of the inorganic layers of the two layers includes the multifunctional material and the multifunctional materials contained in each of the inorganic layers of the two layers are arranged to be substantially staggered from each other. 15. The method of claim 14,
Wherein an uppermost surface of the sealing layer is substantially planarized.

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