KR102415654B1 - Organic light emitting device - Google Patents

Abstract

The present invention provides an organic light emitting layer positioned between a first electrode and a second electrode and formed in a plurality of sub-pixel regions, a plurality of light emitting units including the organic light emitting layer, and formed by stacking the plurality of light emitting units between the plurality of light emitting units and a charge generation layer positioned in Each of the second electrodes positioned in the step is characterized in that the organic light emitting device is formed at different positions.

Description

Organic light emitting device {ORGANIC LIGHT EMITTING DEVICE}

The present invention relates to an organic light emitting device, and more particularly, to an organic light emitting device capable of improving optical reliability by improving light leakage defects in an organic light emitting display device.

An organic light emitting display device (OLED) is a self-emission type display device, in which electrons and holes are respectively injected into the light emitting layer from an electrode for electron injection and an anode for hole injection. This is a display device using an organic light emitting diode that emits light when excitons in which injected electrons and holes are combined fall from an excited state to a ground state.

The organic light emitting diode display is divided into a top emission method, a bottom emission method, a dual emission method, etc. according to a direction in which light is emitted, and a passive matrix type (Passive) type according to a driving method. Matrix) and active matrix type.

Unlike a liquid crystal display (LCD), an organic light emitting diode display does not require a separate light source, so it can be manufactured in a lightweight and thin form. In addition, the organic light emitting diode display is being researched as a next-generation display because it is advantageous in terms of power consumption due to low voltage driving and excellent color realization, response speed, viewing angle, and contrast ratio (CR).

With the development of high resolution displays, the number of pixels per unit area increases and high luminance is required. There is a problem in that the reliability of the organic light emitting diode decreases and power consumption increases.

Therefore, it is necessary to overcome the technical limitations of improving the luminous efficiency, lifespan, and power consumption of the organic light emitting device, which are factors that impede the quality and productivity of the organic light emitting display device. Various studies are being conducted for the development of an organic light emitting device capable of improving characteristics.

In order to improve the quality and productivity of the organic light emitting diode display, various organic light emitting device structures have been proposed to improve the efficiency, lifespan, and power consumption of the organic light emitting diode.

Accordingly, in addition to the organic light emitting device structure to which one stack, that is, one electroluminescence unit (EL unit) is applied, a plurality of stacks, that is, stacking of a plurality of light emitting units, is used. A tandem organic light emitting device structure has also been proposed.

However, since the light emitting effect does not increase simply by simply stacking a plurality of light emitting units to form a plurality of light emitting units, the same effect as when a plurality of light emitting devices are connected in series in emitting light from the plurality of light emitting units can be obtained. there should be

In order to obtain an improved light emitting effect by connecting the plurality of light emitting devices as described above, a charge generation layer (CGL) should be applied between the plurality of stacked light emitting units.

However, when the charge generation layer (CGL) is applied in such a tandem structure, that is, an organic light emitting device structure using a stacking of a plurality of light emitting units, a light leakage phenomenon in which unwanted light from adjacent sub-pixels is emitted occurs. There is a phenomenon in which the optical reliability of the organic light emitting display device is deteriorated.

That is, when an electric field is applied to the red sub-pixel, undesired adjacent green sub-pixels partially emit light, or when an electric field is applied to the blue sub-pixel, undesirable adjacent green sub-pixels partially emit light.

Accordingly, the inventor of the present invention has invented a new organic light emitting device structure for preventing light leakage in an organic light emitting device structure using a plurality of stacks, that is, stacking a plurality of light emitting units.

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic light-emitting device capable of improving optical reliability by improving light leakage defects emitted by adjacent sub-pixels in an organic light-emitting display device.

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

In the organic light emitting diode according to an embodiment of the present invention, there is provided an organic light emitting device capable of improving optical reliability by preventing light leakage defects emitted by adjacent sub-pixels.

The present invention includes an organic light emitting layer disposed between a first electrode and a second electrode and formed in a plurality of sub-pixel regions, a plurality of light emitting units including the organic light emitting layer, and a charge generating layer positioned between the plurality of light emitting units, The charge generation layer is located in the plurality of sub-pixel areas, and provides an organic light-emitting device having a step difference at a boundary between the plurality of sub-pixel areas.

The organic emission layer may include a red emission layer, a green emission layer, and a blue emission layer.

The thickness of the red light emitting layer, the thickness of the green light emitting layer, and the thickness of the blue light emitting layer may be different from each other.

A thickness of the red light-emitting layer may be greater than a thickness of the green light-emitting layer, and a thickness of the green light-emitting layer may be greater than a thickness of the blue light-emitting layer.

The step difference of the charge generation layer may be 200 Å or more.

In another aspect, the present invention provides an organic light emitting layer disposed between the first electrode and the second electrode and formed in the red, green, and blue sub-pixel regions, a charge generating layer formed between the first electrode and the second electrode, and the organic light emitting layer and a first light emitting unit formed between the first electrode and the charge generating layer and the organic light emitting layer, and a second light emitting unit formed between the charge generating layer and the second electrode, wherein the charge The generation layer is located in the red, green, and blue sub-pixel regions, and provides an organic light emitting device having a step difference at the boundary between the red, green, and blue sub-pixel regions.

The organic emission layer may include a red emission layer, a green emission layer, and a blue emission layer.

A thickness of the red light emitting layer of the first light emitting unit may be greater than a thickness of the red light emitting layer of the second light emitting unit.

A thickness of the blue light emitting layer of the first light emitting unit may be smaller than a thickness of the blue light emitting layer of the second light emitting unit.

The thickness of the green light emitting layer of the first light emitting unit may be smaller than the thickness of the red light emitting layer of the first light emitting unit and greater than the thickness of the blue light emitting layer of the first light emitting unit.

A thickness of the red light emitting layer of the first light emitting unit may be smaller than a thickness of the red light emitting layer of the second light emitting unit.

A thickness of the blue light emitting layer of the first light emitting unit may be greater than a thickness of the blue light emitting layer of the second light emitting unit.

A thickness of the green light emitting layer of the first light emitting unit may be greater than a thickness of the red light emitting layer of the first light emitting unit and smaller than a thickness of the blue light emitting layer of the first light emitting unit.

In another aspect, the present invention provides an organic light emitting layer disposed between the first electrode and the second electrode and formed in the red, green, and blue sub-pixel regions, a charge generating layer formed between the first electrode and the second electrode, and the organic light emitting layer a first light emitting unit and the organic light emitting layer formed between the first electrode and the charge generating layer, and a second light emitting unit and the first light emitting unit formed between the charge generating layer and the second electrode. a first hole transport layer positioned under the organic light emitting layer of to provide an organic light-emitting device having a step difference at the boundary between the red, green, and blue sub-pixel regions.

The organic emission layer may include a red emission layer, a green emission layer, and a blue emission layer.

A thickness of the first hole transport layer in the green sub-pixel region may be smaller than a thickness of the first hole transport layer in the red sub-pixel region and greater than a thickness of the first hole transport layer in the blue sub-pixel region .

A thickness of the second hole transport layer in the green sub-pixel region may be greater than a thickness of the second hole transport layer in the red sub-pixel region and less than a thickness of the first hole transport layer in the blue sub-pixel region .

When the organic light emitting device using the stacking of a plurality of light emitting units according to an embodiment of the present invention is applied, the charge generating layer CGL is formed to have a step difference in each of the red, green, and blue sub pixel regions, so that adjacent sub An influence of a lateral current between pixels may be minimized.

Accordingly, a phenomenon in which unwanted adjacent sub-pixels emit light does not occur, and light leakage defects of the organic light emitting diode display may be improved.

In addition, the optical reliability of the organic light emitting diode display using the stacking of a plurality of light emitting units may be improved by preventing light leakage failure caused by unwanted adjacent sub-pixels.

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

Since the content of the invention described in the problems to be solved above, the means for solving the problems, and the effects do not specify the essential characteristics of the claims, the scope of the claims is not limited by the matters described in the content of the invention.

1 is a diagram illustrating a unit device structure for horizontal current level evaluation when a charge generation layer is applied.
FIG. 2 is a diagram illustrating a horizontal current level test result when a charge generation layer is applied according to the device structure of FIG. 1 .
3 is a schematic cross-sectional view of an organic light emitting diode according to a comparative example of the present invention.
4 is a schematic cross-sectional view of an organic light emitting diode according to an embodiment of the present invention. 5 is a schematic cross-sectional view of an organic light emitting diode according to another embodiment of the present invention.
6 is a schematic cross-sectional view of an organic light emitting device according to another embodiment of the present invention.
7 is a schematic cross-sectional view of an organic light emitting device according to another embodiment of the present invention.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be embodied in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, proportions, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative and the present invention is not limited to the illustrated matters. Like reference numerals refer to like elements throughout. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. When 'including', 'having', 'consisting', etc. mentioned in this specification are used, other parts may be added unless 'only' is used. When a component is expressed in the singular, the case in which the plural is included is included unless otherwise explicitly stated.

In interpreting the components, it is construed as including an error range even if there is no separate explicit description. In the case of a description of the positional relationship, for example, when the positional relationship of two parts is described as 'on', 'on', 'on', 'beside', etc., 'right' Alternatively, one or more other parts may be positioned between two parts unless 'directly' is used.

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

Each feature of the various embodiments of the present invention can be partially or wholly combined or combined with each other, technically various interlocking and driving are possible, and each of the embodiments may be independently implemented with respect to each other or implemented together in a related relationship. may be

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

1 is a diagram illustrating a structure of a unit device for horizontal current level evaluation when a charge generation layer is applied.

Referring to FIG. 1 , a structure of a unit device for evaluating a horizontal current level when a charge generation layer is applied will be described.

A bank 13 having a constant width W is formed on the substrate 10 formed of glass, and the electrode 1 11 and the electrode 2 12 are positioned adjacent to both sides of the bank 13 . ) was formed to have the same thickness as the bank 13 .

A charge generation layer (CGL) as an organic material layer 14 on top of the bank 13, electrode 1 (11), and electrode 2 (12) was fabricated with different thicknesses (d) of 100 Å, 200 Å, and 1000 Å, respectively. .

As the charge generation layer (CGL), an n-type charge generation layer (n-CGL) in which Alq3 (tris(8-hydroxyquinolino)aluminum) is doped with lithium (Li) and HATCN(1,4,5,8, A single layer of 9,11-hexaazatriphenylene-hexanitrile, p-type charge generation layer (p-CGL), was stacked, and the thickness of the n-type charge generation layer and the p-type charge generation layer was formed in a ratio of 1:1.

In addition, in order to compare the level of lateral current with the unit device in which the charge generation layer CGL is formed, the organic material layer 14 has the same structure as the unit device in which the charge generation layer CGL is formed. A unit device in which NPB (N,N'-Di(naphthalene-1-yl)-N,N'-diphenyl-benzidine), an organic material generally applied to organic light emitting devices, is formed to a thickness of 1000 Å instead of a generation layer (CGL) was produced.

Thereafter, a DC bias voltage (V) was applied to each unit device to measure and compare the current density (mA/cm) level of the unit device according to the applied voltage.

FIG. 2 is a diagram illustrating a horizontal current level test result when a charge generation layer is applied according to the device structure of FIG. 1 .

2 is a unit device in which NPB is formed to a thickness of 1000 Å as the organic layer 14 in the unit device structure shown in FIG. In the formed unit element structure, the current density level is compared.

That is, when a DC bias voltage is applied to the electrodes 1 ( 11 ) and 2 ( 12 ) of each unit element, a current that flows from the electrode 1 ( 11 ) to the electrode 2 ( 12 ) through the organic material layer 14 . The levels of density were compared.

By understanding the level of the current density of the organic material and the charge generating layer (CGL), it is possible to check the level of the lateral current, which is the flow of current that may occur when the charge generating layer (CGL) is applied.

As can be seen in FIG. 2 , a unit device in which NPB is formed to a thickness of 1000 Å as the organic layer 14 and a charge generation layer (CGL) in a thickness of 100 Å, 200 Å, and 1000 Å as the organic layer 14 is formed. Comparing the current density levels, the current density levels of the unit devices in which the charge generation layer (CGL) was formed to a thickness of 100 Å, 200 Å, and 1000 Å were all higher than those in which the NPB was formed to a thickness of 1000 Å. Therefore, it can be seen that the charge generating layer (CGL) exhibits a higher level of conductivity when compared to an organic material layer generally applied in an organic light emitting device.

In addition, even in the case of a unit device in which the charge generation layer (CGL) is formed to a thickness of 200 Å, which is as low as 1/5 of 1000 Å, which is the thickness of NPB, and 100 Å, which is as low as 1/10, the organic material layer 14 ) showed a high level of current density when compared to a unit device in which an NPB having a thickness of 1000 Å was formed. Therefore, it can be seen that the charge generating layer (CGL) exhibits very high conductivity even at a low thickness when compared to a general organic material.

That is, as described with reference to FIG. 2 , since the charge generating layer CGL has relatively high conductivity compared to other organic materials applied in the organic light emitting device, when the charge generating layer CGL is formed by being connected to the same position, As shown in FIG. 1 , a lateral current, which is a flow of current through the organic material layer 14 , that is, the charge generating layer CGL, may be generated in the direction from the electrode 1 11 to the electrode 2 12 .

Therefore, in an organic light emitting device to which a plurality of stack structures, that is, stacking of a plurality of light emitting units, is applied, when the charge generation layer CGL is commonly connected to the red, green, and blue sub-pixel regions and is formed at the same location, the charge It can be seen that a lateral current is generated from the generation layer CGL to an adjacent sub-pixel area, and accordingly, light is emitted from the undesired sub-pixel area, thereby causing a light leakage defect.

In addition, as shown in FIG. 2 , it can be confirmed that the level of the horizontal current is higher than in the case of a unit device having a large charge generation layer (CGL), and in order to minimize the influence of the horizontal current, the charge generation layer (CGL) ), it can be seen that it is desirable to form the thickness as small as possible.

In general, the charge generation layer (CGL) can be formed to a thickness of 100 Å or more and 300 Å or less, which is a level capable of functioning as a charge generation layer in the structure of an organic light emitting device. was formed.

Hereinafter, organic light emitting devices according to Comparative Examples and Examples of the present invention will be described.

3 is a schematic cross-sectional view of an organic light emitting diode 300 according to a comparative example of the present invention.

Referring to FIG. 3 , a red sub-pixel region Rp, a green sub-pixel region Gp, and a blue sub-pixel region Bp are defined on a substrate. The organic light emitting diode 300 includes a first electrode 310 (anode), a hole injection layer 320 (hole injection layer: HIL), a first hole transport layer 330 (1 ^st hole transporting layer: 1 ^st HTL), and a first red color. The emission layer 340 (1 ^st Red emission layer: 1 ^st Red EML), the first green emission layer (341, 1 ^st Green emission layer: 1 ^st Green EML), and the first blue emission layer (342, 1 ^st Blue emission layer: 1 ^st ) Blue EML), the first electron transport layer 350 (1 ^st electron transporting layer: 1 ^st ETL), the charge generation layer (360, charge generation layer: CGL), the second hole transport layer (370, 2 ^nd hole transporting) layer: 2 ^nd HTL), a second red emission layer (380, 2 ^nd Red emission layer: 2 ^nd Red EML), a second green emission layer (381, 2 ^nd Green emission layer: 2 ^nd Green EML), and a second blue emission layer ( 382 (2 ^nd Blue emission layer: 2 ^nd Blue EML), the organic emission layer, the second electron transport layer (390, 2 ^nd electron transporting layer: 2 ^nd ETL) and a second electrode (400, cathode) is included.

An organic light emitting layer including a hole injection layer 320 , a first hole transport layer 330 , a first red light emitting layer 340 , a first green light emitting layer 341 , and a first blue light emitting layer 342 , and a first electron transport layer 350 ) constitutes the first light emitting unit 3100, 1 ^st EL Unit.

In addition, the organic light emitting layer and the second electron transport layer 390 including the second hole transport layer 370 , the second red light emitting layer 380 , the second green light emitting layer 381 , and the second blue light emitting layer 382 are a second light emitting unit (3200, ^2nd EL Unit).

In addition, in the organic light emitting diode display including the organic light emitting diode according to the embodiment of the present invention, a gate line and a data line that cross each other on a substrate and define each sub-pixel area, and a power supply extending parallel to any one of them Wiring is positioned, and a switching thin film transistor connected to a gate line and a data line and a driving thin film transistor connected to the switching thin film transistor are positioned in each sub-pixel area. The driving thin film transistor is connected to the first electrode 310 . Although it is illustrated that the first electrode 310 is formed in all of the three sub-pixel areas, the first electrode 310 may be formed in each of the three sub-pixel areas Rp, Gp, and Bp to be spaced apart from each other.

The first electrode 310 may also be formed as a reflective electrode. For example, the first electrode 310 may include a layer of a transparent conductive material having a high work function, such as indium-tin-oxide (ITO), and a reflection such as silver (Ag) or a silver alloy (Ag alloy). It may include a material layer.

The hole injection layer 320 and the first hole transport layer 330 correspond to all of the red, green, and blue sub-pixel regions Rp, Gp, and Bp and are positioned on the first electrode 310 .

The hole injection layer 320 may serve to facilitate hole injection, and may include HATCN (1,4,5,8,9,11-hexaazatriphenylene-hexanitrile) and CuPc (cupper phthalocyanine), PEDOT (poly(3) ,4)-ethylenedioxythiophene), PANI (polyaniline), and NPD (N,N-dinaphthyl-N,N'-diphenylbenzidine) may consist of any one or more selected from the group consisting of, but is not limited thereto.

The first hole transport layer 330 and the second hole transport layer 370 are formed to correspond to the red pixel region Rp, the green pixel region Gp, and the blue pixel region Bp, respectively.

The first and second hole transport layers 330 and 370 serve to facilitate hole transport, and NPD (N,N-dinaphthyl-N,N'-diphenylbenzidine), TPD (N,N'-bis-( 3-methylphenyl)-N,N'-bis-(phenyl)-benzidine), s-TAD and MTDATA(4,4',4"-Tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine) It may consist of any one or more selected from the group consisting of, but is not limited thereto.

The first and second red light emitting layers 340 and 380 , the first and second green light emitting layers 341 and 381 , and the first and second blue light emitting layers 342 and 382 are red, green, and blue sub-pixel regions Rp, respectively. , Gp, Bp).

In addition, each of the red light emitting layers 340 and 380 , the green light emitting layers 341 and 381 , and the blue light emitting layers 342 and 382 may include a light emitting material that emits red, green, and blue light, respectively, and the light emitting material is a phosphorescent material or It can be formed using a fluorescent material.

More specifically, the first and second red emission layers 340 and 380 include a host material including CBP (carbazole biphenyl) or mCP (1,3-bis (carbazol-9-yl), PIQIr (acac) Any one or more selected from the group consisting of (bis(1-phenylisoquinoline) acetylacetonate iridium), PQIr(acac)(bis(1-phenylquinoline) acetylacetonate iridium), PQIr(tris(1-phenylquinoline) iridium) and PtOEP(octaethylporphyrin platinum) may be made of a phosphorescent material including a dopant containing

In addition, the first and second green emission layers 341 and 381 include a host material including CBP or mCP, and a dopant such as an Ir complex including Ir(ppy)3 (fac tris(2-phenylpyridine)iridium). It may be formed of a phosphorescent material including a material, and alternatively, may be formed of a fluorescent material containing Alq3 (tris(8-hydroxyquinolino)aluminum), but is not limited thereto.

In addition, the first and second blue emission layers 342 and 382 may include a host material including CBP or mCP, and may be formed of a phosphorescent material including a dopant material including (4,6-F2ppy)2Irpic. In addition, the first and second fluorescent materials comprising any one selected from the group consisting of spiro-DPVBi, spiro-6P, distylbenzene (DSB), distrylarylene (DSA), PFO-based polymers and PPV-based polymers. The blue light emitting layers 342 and 382 may be formed, but the present invention is not limited thereto.

The first electron transport layer 350 is located in the first red light emitting layer 340, the first green light emitting layer 341, and the first blue light emitting layer 342, and the second electron transport layer 390 is the second red light emitting layer 380, It is positioned on the second green light emitting layer 381 and the second blue light emitting layer 382 .

The thickness of the first and second electron transport layers 350 and 390 may be adjusted in consideration of electron transport characteristics. The first and second electron transport layers 350 and 390 may serve as electron transport and injection, and an electron injection layer (EIL) is separately formed on the first and second electron transport layers 350 and 390 . can be formed in

The first and second electron transport layers 350 and 390 serve to facilitate electron transport, and Alq3 (tris(8-hydroxyquinolino)aluminum), PBD(2-(4-biphenylyl)-5-(4-) tert-butylpheny)-1,3,4oxadiazole), TAZ, spiro-PBD, BAlq and SAlq may be formed of at least one selected from the group consisting of, but not limited thereto.

The charge generation layer 360 is formed between the first light emitting unit 3100 and the second light emitting unit 3200 and serves to adjust the charge balance between the respective light emitting units.

The charge generation layer 360 includes an n-type charge generation layer (n-CGL) that helps inject electrons into the first light emitting unit 3100 and a p-type charge generation layer p that helps inject holes into the second light emitting unit 3200 . -CGL) can be divided and formed.

More specifically, the n-type charge generating layer (n-CGL) serving as an electron injection may be formed of an alkali metal, an alkali metal compound, an organic material serving as an electron injection, or a compound thereof. For example, it may be formed of a mixed layer of an n-type material such as an anthracene derivative doped with lithium (Li) and cesium (Cs), but is not limited thereto.

In addition, the p-type charge generating layer (p-CGL) serving as a hole injection may be formed of an organic material used as a material for the first and second hole injection layers 330 and 370 . For example, it may be formed of a single layer of a p-type material such as HATCN or F4-TCNQ, but is not limited thereto.

The electron injection layer (EIL) is Alq3 (tris(8-hydroxyquinolino)aluminum), PBD(2-(4-biphenylyl)-5-(4-tert-butylpheny)-1,3,4oxadiazole), TAZ, spiro-PBD , BAlq or SAlq may be used, but is not limited thereto. In addition, it is possible to abbreviate|omit the electron injection layer EIL.

Here, the structure is not limited according to the embodiment of the present invention, and the hole injection layer 320, the first and second hole transport layers 330 and 370, the first and second electron transport layers 350 and 390, and At least one of the electron injection layer EIL may be omitted. In addition, forming the hole injection layer 320, the first and second hole transport layers 330 and 370, the first and second electron transport layers 350 and 390, and the electron injection layer (EIL) as two or more layers is also It is possible.

The second electrode 400 is positioned on the second electron injection layer 390 . For example, the second electrode 400 may be made of an alloy of magnesium and silver (Mg:Ag), and may have a transflective property of several tens to several hundreds of Å. That is, the light emitted from the organic light emitting layer is displayed to the outside through the second electrode 400 , and since the second electrode 400 has a transflective property, some light is directed back to the first electrode 310 . do.

In this way, repeated reflection occurs between the first electrode 310 and the second electrode 400 acting as a reflective layer, which is referred to as a microcavity effect. That is, light is repeatedly reflected in the cavity between the first electrode 310 and the second electrode 400 to increase light efficiency.

In addition, light from the organic light emitting layer may be externally displayed through the first electrode 310 by forming the first electrode 310 as a transmissive electrode and forming the second electrode 400 as a reflective electrode.

In addition, although not shown in the drawings of the present invention, a capping layer (CPL) is for increasing the light extraction effect of the organic light emitting diode, and may be formed on the second electrode 400 . The capping layer includes first and second hole transport layers 330 and 370 materials, first and second electron transport layers 350 and 390 materials, and first and second red light emitting layers 340 and 380 , first and second materials. It may be formed of any one of a host material of the green light emitting layers 341 and 381 and the first and second blue light emitting layers 342 and 382 . In addition, it is possible to omit the capping layer.

Referring to FIG. 3 , the structure of the organic light emitting diode 300 according to the comparative example of the present invention will be described in more detail.

ITO (indium-tin-oxide, indium-tin-oxide) is formed to a thickness of 70 Å as the first electrode 310, a silver alloy is formed thereon to a thickness of 1000 Å, and then ITO was formed to a thickness of 70 Å.

Referring to FIG. 3 , HATCN was formed to a thickness of 70 Å as the hole injection layer 320 on the first electrode 310 , and NPD was formed to a thickness of 500 Å as the first hole transport layer 330 thereon. .

After forming a beryllium compound derivative as a host material to a thickness of 300 Å as a first red light emitting layer 340 in the red sub-pixel region Rp on the first hole transport layer 330 , a dopant is applied to 5 % level to form a first red light emitting layer 340 .

In addition, after forming CBP, which is a host material, to a thickness of 300 Å as the first green light emitting layer 341 in the green sub-pixel region Gp on the first hole transport layer 330 , doping with a dopant to a level of 5% Thus, a first green light emitting layer 341 was formed.

In addition, after forming an anthracene derivative as a host material to a thickness of 300 Å as the first blue light emitting layer 342 in the blue sub-pixel region Bp on the first hole transport layer 130 , a dopant is applied to 5 A first blue light emitting layer 342 was formed by doping at a % level.

An anthracene derivative and lithium quinolate (Liq) are mixed at a ratio of 1:1 as a first electron transport layer 350 on the first red light emitting layer 340 , the first green light emitting layer 341 , and the first blue light emitting layer 342 . to form a thickness of 70 Å.

An n-type charge generation layer (n-CGL) and a p-type charge generation layer (p-CGL) are sequentially stacked on the first electron transport layer 350 as a charge generation layer 360 . After forming Alq3 to a thickness of 100 Å as an n-type charge generation layer, it was formed by doping with lithium (Li), and HATCN was formed to a thickness of 100 Å as a p-type charge generation layer thereon to a thickness of 200 Å. (360) was formed.

An NPD was formed to a thickness of 600 Å as the second hole transport layer 370 on the charge generation layer 360 .

After forming a beryllium compound derivative as a host material to a thickness of 300 Å as the second red light emitting layer 380 in the red sub-pixel region Rp on the second hole transport layer 370 , a dopant is applied to 5 A second red light emitting layer 380 was formed by doping at a % level.

In addition, after forming CBP as a host material to a thickness of 300 Å as the second green light emitting layer 381 in the green sub-pixel region Gp on the second hole transport layer 370 , doping with a dopant to a level of 5% Thus, a second green light emitting layer 381 was formed.

In addition, after forming an anthracene derivative as a host material to a thickness of 300 Å as the second blue light emitting layer 382 in the blue sub-pixel region Bp on the second hole transport layer 370 , a dopant is applied to 5 A second blue light emitting layer 382 was formed by doping at a % level.

Anthracene derivative and lithium quinolate (Liq) are mixed in a ratio of 1:1 as a second electron transport layer 390 on the second red light emitting layer 380 , the second green light emitting layer 381 , and the second blue light emitting layer 382 . to form a thickness of 300 Å.

140Å of a magnesium-silver alloy (Mg:Ag) in which magnesium (Mg) and silver (Ag) are mixed in a ratio of 9:1 as a second electrode 400 as a semi-transmissive electrode on an upper portion of the second electron transport layer 390 . was formed to a thickness of

Looking at the step difference at the boundary between the plurality of sub-pixel regions of the organic light emitting diode 300 with respect to the first electrode 310 in the comparative example of FIG. 3 , the first red light emitting layer 340 and the first green light emitting layer No step is formed between 341 , and no step is formed between the first green light emitting layer 341 and the first blue light emitting layer 342 , and further, a step is not formed between the first blue light emitting layer 342 and the first red light emitting layer 342 . No step is formed even between (341).

Accordingly, the charge generation layer 360 of the red sub-pixel region Rp, the charge generation layer 360 of the green sub-pixel region Gp, and the charge generation layer 360 of the blue sub-pixel region Bp are connected to each other and formed do.

That is, in the case of the organic light emitting device 300 according to the comparative example of the present invention, a step is not formed in the charge generation layer 360 and is formed to be connected between adjacent sub-pixels, and thus the charge generation layer 360 with high conductivity is formed. A horizontal current is generated from the to the adjacent sub-pixels, resulting in a light leakage phenomenon in which unwanted adjacent sub-pixels emit light together.

Accordingly, when the charge generation layer 360 is formed to have a step difference and not to be connected to each other between adjacent sub-pixel regions, generation of a horizontal current due to the high conductivity of the charge generation layer 360 can be prevented, and thus, an unwanted It is possible to prevent a light leakage phenomenon in which adjacent sub-pixels emit light together.

4 is a schematic cross-sectional view of an organic light emitting device 100A according to an embodiment of the present invention.

In describing the present embodiment, descriptions of the same or corresponding components as those of the comparative example described above will be omitted.

Hereinafter, the structure of the organic light emitting diode 100A according to an embodiment of the present invention will be described in more detail with reference to this reference.

Referring to FIG. 4 , as the first electrode 110 , indium-tin-oxide (ITO) is formed to a thickness of 70 Å, and an Ag alloy is formed thereon to a thickness of 1000 Å. After that, ITO was formed to a thickness of 70 Å on the top.

HATCN was formed to a thickness of 70 Å as the hole injection layer 120a on the first electrode 110, and NPD was formed to a thickness of 500 Å as the first hole transport layer 130a thereon.

After forming a beryllium compound derivative as a host material to a thickness of 650 Å as a first red light emitting layer 140a in the red sub-pixel region Rp on the first hole transport layer 130a, a dopant is applied to 5 % level to form a first red light emitting layer 140a.

In addition, after forming CBP as a host material to a thickness of 400 Å as the first green light emitting layer 141a in the green sub-pixel region Gp on the first hole transport layer 130a, doping with a dopant to a level of 5% Thus, a first green light emitting layer 141a was formed.

In addition, after forming an anthracene derivative as a host material to a thickness of 200 Å as the first blue light emitting layer 142a in the blue sub-pixel region Bp on the first hole transport layer 130a, a dopant is added to 5 % level to form a first blue light emitting layer 142a.

Anthracene derivative and lithium quinolate (Liq) are mixed in a ratio of 1:1 as a first electron transport layer 150a on the first red light-emitting layer 140a, the first green light-emitting layer 141a, and the first blue light-emitting layer 142a. to form a thickness of 70 Å.

An n-type charge generation layer (n-CGL) and a p-type charge generation layer (p-CGL) were sequentially stacked on the first electron transport layer 150a as a charge generation layer 160a to form a charge generation layer 160a. After forming Alq3 to a thickness of 100 Å as an n-type charge generation layer, it was formed by doping with lithium (Li), and HATCN was formed to a thickness of 100 Å as a p-type charge generation layer thereon to a thickness of 200 Å. (160a) was formed.

An NPD was formed to a thickness of 400 Å as the second hole transport layer 170a on the charge generation layer 160a.

After forming a beryllium compound derivative as a host material to a thickness of 650 Å as the second red light emitting layer 180a in the red sub-pixel region Rp on the second hole transport layer 170a, a dopant is applied to 5 % level to form a second red light emitting layer 180a.

In addition, after forming CBP as a host material to a thickness of 400 Å as the second green light emitting layer 181a in the green sub-pixel region Gp on the second hole transport layer 170a, doping with a dopant to a level of 5% Thus, a second green light emitting layer 181a was formed.

In addition, after forming an anthracene derivative as a host material to a thickness of 200 Å as the second blue light emitting layer 182a in the blue sub-pixel region Bp on the second hole transport layer 170a, a dopant is applied to 5 % level to form a second blue light emitting layer 182a.

Anthracene derivative and lithium quinolate (Liq) are mixed in a ratio of 1:1 as a second electron transport layer 190a on the second red light-emitting layer 180a, the second green light-emitting layer 181a, and the second blue light-emitting layer 182a. to form a thickness of 300 Å.

140 Å of a magnesium-silver alloy (Mg:Ag) in which magnesium (Mg) and silver (Ag) are mixed in a ratio of 9:1 as the second electrode 200 as a transflective electrode on the second electron transport layer 190a was formed to a thickness of

4 , looking at the step difference between the sub-pixels of the organic light emitting diode 100A with respect to the first electrode 110 , the step difference between the first red light emitting layer 140a and the first green light emitting layer 141a was formed at a level of 250 Å, and the step difference between the first green light emitting layer 141a and the first blue light emitting layer 142a was formed at a level of 200 Å, and the first blue light emitting layer 142a and the first red light emitting layer 142a The step difference between (140a) was formed at a level of 250 Å.

As described above, in the organic light emitting device 100A according to the present embodiment, the step difference between the first red light emitting layer 140a and the first green light emitting layer 141a, the first green light emitting layer 141a and the first blue light emitting layer 142a As the step difference between the two layers and the step difference between the first blue light emitting layer 142a and the first red light emitting layer 140a are all formed to a level of 200 Å or more, the red, green, and blue sub-pixel regions of the upper portion of the organic light emitting layer are respectively formed. The charge generation layer 160a also has a step difference of 200 Å or more.

Accordingly, the charge generation layer 160a of the red sub-pixel region Rp, the charge generation layer 160a of the green sub-pixel region Gp, and the charge generation layer 160a of the blue sub-pixel region Bp are substantially mutually will not be connected. The fact that the charge generation layer 160a is not substantially connected between the two sub-pixel areas means that the charge generation layer 160a formed in each sub-pixel area is short-circuited by a step and even if not short-circuited, as described above. This means that almost no horizontal current will flow. In the same meaning as above, the charge generation layer 160a may be substantially short-circuited due to a step difference.

As a result, in the organic light emitting diode 100A according to the embodiment of the present invention, horizontal current is not generated due to the high conductivity of the charge generating layer 160a, so that undesirable adjacent sub-pixels emit light together. it can be prevented

5 is a schematic cross-sectional view of an organic light emitting diode 100B according to another embodiment of the present invention.

In describing the present embodiment, descriptions of the same or corresponding components as those of the comparative example described above will be omitted.

Hereinafter, the structure of the organic light emitting diode 100B according to an embodiment of the present invention will be described in more detail with reference to this.

Referring to FIG. 5 , as the first electrode 110 , indium-tin-oxide (ITO) is formed to a thickness of 70 Å, and an Ag alloy is formed thereon to a thickness of 1000 Å. After that, ITO was formed to a thickness of 70 Å on the top.

HATCN was formed to a thickness of 70 Å as the hole injection layer 120b on the first electrode 110 , and NPD was formed to a thickness of 500 Å as the first hole transport layer 130b thereon.

After forming a beryllium compound derivative as a host material to a thickness of 850 Å as the first red light emitting layer 140b in the red sub-pixel region Rp on the first hole transport layer 130b, a dopant is applied to 5 % level to form a first red light emitting layer 140b.

In addition, after forming CBP as a host material to a thickness of 400 Å as the first green light emitting layer 141b in the green sub-pixel region Gp on the first hole transport layer 130b, doping with a dopant to a level of 5% Thus, a first green light emitting layer 141b was formed.

In addition, after forming an anthracene derivative as a host material to a thickness of 100 Å as the first blue light emitting layer 142b in the blue sub-pixel region Bp on the first hole transport layer 130b, a dopant of 5 A first blue light emitting layer 142b was formed by doping at a % level.

Anthracene derivative and lithium quinolate (Liq) are mixed in a ratio of 1:1 as a first electron transport layer 150b on the first red light emitting layer 140b, the first green light emitting layer 141b, and the first blue light emitting layer 142b. to form a thickness of 70 Å.

An n-type charge generation layer (n-CGL) and a p-type charge generation layer (p-CGL) are sequentially stacked on the first electron transport layer 150b as a charge generation layer 160b to form a charge generation layer 160b. After forming Alq3 to a thickness of 100 Å as an n-type charge generation layer, it was formed by doping with lithium (Li), and HATCN was formed to a thickness of 100 Å as a p-type charge generation layer thereon to a thickness of 200 Å. (160b) was formed.

An NPD was formed to a thickness of 500 Å as the second hole transport layer 170b on the charge generation layer 160b.

After forming a beryllium compound derivative as a host material to a thickness of 300 Å as a second red light emitting layer 180b in the red sub-pixel region Rp on the second hole transport layer 170b, a dopant is applied to 5 % level to form a second red light emitting layer 180b.

In addition, after forming CBP as a host material to a thickness of 400 Å as the second green light emitting layer 181b in the green sub-pixel region Gp on the second hole transport layer 170b, doping with a dopant to a level of 5% Thus, a second green light emitting layer 181b was formed.

In addition, after forming an anthracene derivative as a host material to a thickness of 450 Å as the second blue light emitting layer 182b in the blue sub-pixel region Bp on the second hole transport layer 170b, a dopant is applied to 5 A second blue light emitting layer 182b was formed by doping at a % level.

Anthracene derivative and lithium quinolate (Liq) are mixed in a ratio of 1:1 as a second electron transport layer 190b on the second red light emitting layer 180b, the second green light emitting layer 181b, and the second blue light emitting layer 182b. to form a thickness of 300 Å.

140 Å of a magnesium-silver alloy (Mg:Ag) in which magnesium (Mg) and silver (Ag) are mixed in a ratio of 9:1 as the second electrode 200 as a transflective electrode on the second electron transport layer 190a was formed to a thickness of

As can be seen from FIG. 5 , looking at the step difference between the sub-pixels of the organic light-emitting device 100B with respect to the first electrode 110 , the difference between the first red light-emitting layer 140b and the first green light-emitting layer 141b is observed. The step was formed at a level of 450 Å, and the step between the first green light emitting layer 141b and the first blue light emitting layer 142b was formed at a level of 300 Å, and the first blue light emitting layer 142b and the first red light emitting layer ( 140b) was formed at a level of 750 Å.

As described above, in the organic light emitting device 100B according to the present embodiment, the step difference between the first red light emitting layer 140b and the first green light emitting layer 141b, the first green light emitting layer 141b and the first blue light emitting layer 142b ) and the step between the first blue light emitting layer 142b and the first red light emitting layer 140b are all formed at a level of 300 Å or more.

Accordingly, the charge generation layers 160b respectively formed in the red, green, and blue sub-pixel regions Rp, Gp, and Bp on the upper portion of the organic light emitting layer have a step difference of 300 Å or more.

Due to the step difference, the charge generation layer 160b of the red sub-pixel region Rp, the charge generation layer 160b of the green sub-pixel region Gp, and the charge generation layer 160b of the blue sub-pixel region Bp are formed. They are not practically connected to each other.

As a result, in the organic light emitting diode 100B according to the embodiment of the present invention, horizontal current is not generated due to the high conductivity of the charge generating layer 160b, so that undesirable adjacent sub-pixels emit light together. it can be prevented

6 is a schematic cross-sectional view of an organic light emitting diode 100C according to another embodiment of the present invention.

In the description of the present embodiment, a description of the same or corresponding components to the previously described comparative example will be omitted.

Hereinafter, the structure of the organic light emitting device 100C according to the embodiment of the present invention will be described in more detail with reference to this.

Referring to FIG. 6 , as the first electrode 110 , indium-tin-oxide (ITO) is formed to a thickness of 70 Å, and an Ag alloy is formed thereon to a thickness of 1000 Å. After that, ITO was formed to a thickness of 70 Å on the top.

HATCN was formed to a thickness of 70 Å as the hole injection layer 120c on the first electrode 110 , and NPD was formed to a thickness of 500 Å as the first hole transport layer 130c on the upper portion of the first electrode 110 .

After forming a beryllium compound derivative as a host material to a thickness of 100 Å as the first red light emitting layer 140c in the red sub-pixel region Rp on the first hole transport layer 130c, a dopant is applied to 5 % level to form a first red light emitting layer 140c.

In addition, after forming CBP as a host material to a thickness of 400 Å as the first green light emitting layer 141c in the green sub-pixel region Gp on the first hole transport layer 130c, doping with a dopant to a level of 5% Thus, a first green light emitting layer 141c was formed.

In addition, after forming an anthracene derivative as a host material to a thickness of 850 Å as the first blue light emitting layer 142c in the blue sub-pixel region Bp on the first hole transport layer 130c, a dopant is added as 5 A first blue light emitting layer 142c was formed by doping at a % level.

Anthracene derivative and lithium quinolate (Liq) are mixed in a ratio of 1:1 as a first electron transport layer 150c on the first red light-emitting layer 140c, the first green light-emitting layer 141c, and the first blue light-emitting layer 142c. to form a thickness of 70 Å.

An n-type charge generation layer (n-CGL) and a p-type charge generation layer (p-CGL) were sequentially stacked on the first electron transport layer 150c as a charge generation layer 160c to form a charge generation layer 160c. After forming Alq3 to a thickness of 100 Å as an n-type charge generation layer, it was formed by doping with lithium (Li), and HATCN was formed to a thickness of 100 Å as a p-type charge generation layer thereon to a thickness of 200 Å. (160c) was formed.

An NPD was formed to a thickness of 500 Å as the second hole transport layer 170c on the charge generation layer 160c.

After forming a beryllium compound derivative as a host material to a thickness of 450 Å as the second red light emitting layer 180c in the red sub-pixel region Rp on the second hole transport layer 170c, a dopant is applied to 5 A second red light emitting layer 180c was formed by doping at a % level.

In addition, after forming CBP as a host material to a thickness of 400 Å as the second green light emitting layer 181c in the green sub-pixel region Gp on the second hole transport layer 170c, doping with a dopant to a level of 5% Thus, a second green light emitting layer 181c was formed.

In addition, after forming an anthracene derivative as a host material to a thickness of 300 Å as the second blue light emitting layer 182c in the blue sub-pixel region Bp on the second hole transport layer 170c, a dopant is added to 5 A second blue light emitting layer 182c was formed by doping at a % level.

Anthracene derivative and lithium quinolate (Liq) are mixed in a ratio of 1:1 as a second electron transport layer 190c on the second red light-emitting layer 180c, the second green light-emitting layer 181c, and the second blue light-emitting layer 182c. to form a thickness of 300 Å.

140 Å of a magnesium-silver alloy (Mg:Ag) in which magnesium (Mg) and silver (Ag) are mixed in a ratio of 9:1 to the second electrode 200 as a transflective electrode on the second electron transport layer 190c was formed to a thickness of

As can be seen from FIG. 6 , looking at the step difference between the sub-pixels of the organic light-emitting device 100C with respect to the first electrode 110 , the difference between the first red light-emitting layer 140c and the first green light-emitting layer 141c is observed. The step was formed at a level of 300 Å, and the step between the first green light emitting layer 141c and the first blue light emitting layer 142c was formed at a level of 450 Å, and the first blue light emitting layer 142c and the first red light emitting layer ( 140c) was formed at a level of 750 Å.

As described above, in the organic light emitting device 100C according to the present embodiment, the step difference between the first red light emitting layer 140c and the first green light emitting layer 141c, the first green light emitting layer 141c and the first blue light emitting layer 142c ) and the step difference between the first blue light emitting layer 142c and the first red light emitting layer 140c are all formed at a level of 300 Å or more, so that the red, green, and blue sub-pixel areas are formed in the upper part of the organic light emitting layer. The charge generation layer 160c also has a step difference of 300 angstroms or more.

Accordingly, the charge generation layer 160c of the red sub-pixel region Rp, the charge generation layer 160c of the green sub-pixel region Gp, and the charge generation layer 160c of the blue sub-pixel region Bp are substantially each other. will not be connected.

As a result, in the organic light emitting diode 100C according to the embodiment of the present invention, horizontal current is not generated due to the high conductivity of the charge generating layer 160c, so that undesirable adjacent sub-pixels emit light together. it can be prevented

7 is a schematic cross-sectional view of an organic light emitting diode 100D according to another embodiment of the present invention.

In the description of the present embodiment, a description of the same or corresponding components to the previously described comparative example will be omitted.

Hereinafter, the structure of the organic light emitting device 100D according to an embodiment of the present invention will be described in more detail with reference to this.

Referring to FIG. 7 , as the first electrode 110 , indium-tin-oxide (ITO) is formed to a thickness of 70 Å, and an Ag alloy is formed thereon to a thickness of 1000 Å. After that, ITO was formed to a thickness of 70 Å on the top.

HATCN was formed to a thickness of 70 Å as the hole injection layer 120d on the first electrode 110 .

The NPD is formed as the first hole transport layer 130d on the hole injection layer 120d to have a thickness of 1200 Å in the red sub-pixel region Rp, and is formed to have a thickness of 500 Å in the green sub-pixel region Gp. and formed to have a thickness of 300 Å in the blue sub-pixel region Bp.

In order to form the first hole transport layer 130d to have a step difference in the red sub-pixel region, the green sub-pixel region, and the blue sub-pixel region, a method of depositing with a different thickness for each sub-pixel region using a mask, or It is possible to apply a patterning method using laser thermal transfer.

A beryllium compound (Be complex) derivative as a host material is formed to a thickness of 300 Å as the first red light emitting layer 140d in the red sub-pixel region Rp above the first hole transport layer 130d having a step difference for each sub-pixel region as described above. After that, the first red light emitting layer 140d was formed by doping with a dopant at a level of 5%.

In addition, after forming CBP, a host material to a thickness of 300 Å, as the first green light emitting layer 141d in the green sub-pixel region Gp above the first hole transport layer 130d having a step difference for each sub-pixel region, a dopant (dopant) ) was doped to a level of 5% to form a first green light emitting layer 141d.

In addition, after forming an anthracene derivative, which is a host material, to a thickness of 300 Å as the first blue light emitting layer 142d in the blue sub-pixel region Bp above the first hole transport layer 130d having a step difference for each sub-pixel region. , a dopant at a level of 5% was doped to form a first blue light emitting layer 142d.

Anthracene derivative and lithium quinolate (Liq) are mixed in a ratio of 1:1 as a first electron transport layer 150d on the first red light-emitting layer 140d, the first green light-emitting layer 141d, and the first blue light-emitting layer 142d. to form a thickness of 70 Å.

An n-type charge generation layer (n-CGL) and a p-type charge generation layer (p-CGL) are sequentially stacked on the first electron transport layer 150d as a charge generation layer 160d to form a charge generation layer 160d. After forming Alq3 to a thickness of 100 Å as an n-type charge generation layer, it was formed by doping with lithium (Li), and HATCN was formed to a thickness of 100 Å as a p-type charge generation layer thereon to a thickness of 200 Å. (160d) was formed.

NPD is formed as the second hole transport layer 170d on the charge generation layer 160d to have a thickness of 300 Å in the red sub-pixel region Rp and to have a thickness of 500 Å in the green sub-pixel region Gp. and formed to have a thickness of 1200 Å in the blue sub-pixel region Bp.

In addition, in order to form the first hole transport layer 130d to have a step difference in the red sub-pixel region, the green sub-pixel region, and the blue sub-pixel region, a mask is used to deposit a different thickness for each sub-pixel region. , or it is possible to apply a patterning method using laser thermal transfer.

After forming a beryllium compound derivative as a host material to a thickness of 300 Å as a second red light emitting layer 180d in the red sub-pixel region Rp on the second hole transport layer 170d, a dopant is applied to 5 % level to form a second red light emitting layer 180d.

In addition, after forming CBP as a host material to a thickness of 300 Å as the second green light emitting layer 181d in the green sub-pixel region Gp on the second hole transport layer 170d, doping with a dopant to a level of 5% Thus, a second green light emitting layer 181d was formed.

In addition, an anthracene derivative, which is a host material, is formed to a thickness of 300 Å as the second blue light emitting layer 182d in the blue sub-pixel region Bp on the second hole transport layer 170d, and then a dopant is added to 5 A second blue light emitting layer 182d was formed by doping at a % level.

Anthracene derivative and lithium quinolate (Liq) are mixed in a ratio of 1:1 as a second electron transport layer 190d on the second red light-emitting layer 180d, the second green light-emitting layer 181d, and the second blue light-emitting layer 182d. to form a thickness of 300 Å.

140Å of a magnesium-silver alloy (Mg:Ag) in which magnesium (Mg) and silver (Ag) are mixed in a ratio of 9:1 as the second electrode 200 as a transflective electrode on the second electron transport layer 190d was formed to a thickness of

As can be seen from FIG. 7 , looking at the step difference between the sub-pixels of the organic light-emitting device 100D with respect to the first electrode 110 , the difference between the first red light-emitting layer 140d and the first green light-emitting layer 141d is shown. The step was formed at a level of 700 Å, and the step between the first green light emitting layer 141d and the first blue light emitting layer 142d was formed at a level of 200 Å, and the first blue light emitting layer 142d and the first red light emitting layer ( 140d) was formed at a level of 900 Å.

As described above, in the organic light emitting device 100D according to the present embodiment, the step difference between the first red light emitting layer 140d and the first green light emitting layer 141d, the first green light emitting layer 141d and the first blue light emitting layer 142d ) and the step difference between the first blue light emitting layer 142d and the first red light emitting layer 140d are all formed at a level of 200 Å or more, so that the red, green, and blue sub-pixel areas are formed in the upper part of the organic light emitting layer. The charge generation layer 160d also has a step difference of 200 angstroms or more.

Accordingly, the charge generation layer 160d of the red sub-pixel region Rp, the charge generation layer 160d of the green sub-pixel region Gp, and the charge generation layer 160d of the blue sub-pixel region Bp are substantially mutually will not be connected.

As a result, in the organic light emitting diode 100D according to the embodiment of the present invention, horizontal current is not generated due to the high conductivity of the charge generating layer 160d, so that undesired light leakage occurs in which adjacent sub-pixels emit light together. it can be prevented

As described above, in the case of the comparative example of the present invention, the charge generation layer (CGL) present between the first light emitting unit and the second light emitting unit reduces the step difference in the red sub-pixel area, the green sub-pixel area, and the blue sub-pixel area. When formed to be connected to each other without having, the charge generating layer CGL is commonly formed at the same position on the first light emitting unit.

Accordingly, as can be seen from the comparative example of the present invention, a horizontal current flows from the high-conductivity charge generating layer (CGL) to the adjacent sub-pixels, causing a light leakage defect in which unwanted adjacent sub-pixels emit light together.

However, as in the embodiment according to the present invention, the charge generation layer CGL existing between the first light emitting unit and the second light emitting unit is formed in each of the red sub-pixel region Rp, the green sub-pixel region Gp, and the blue sub-pixel region. Since the pixel region Bp may be formed to have a step difference of 200 Å or greater, the charge generation layers CGL in each sub-pixel region are not substantially connected to each other.

As a result, horizontal current does not flow from the charge generation layer CGL to the adjacent sub-pixels, and thus, unwanted light leakage from adjacent sub-pixels emitting light can be prevented.

Although not described in detail in the specific content and embodiment of the present invention, as in the embodiment of the present invention, the thicknesses of the first hole transport layer 130d and the second hole transport layer 170d between adjacent sub-pixel regions are different from each other. Similarly, in the structure of the organic light emitting device, it is possible to form the thicknesses of the first electron transport layer 150d and the second electron transport layer 190d, which are common layers, different from each other.

In addition, although not specifically described in the specific content and examples of the present invention, when applying a combination of two or more methods among the methods of forming the charge generating layer (CGL) to have a step in the above embodiment, charge generation It is possible to realize that the step of the layer CGL becomes larger, and thus, it is also possible to obtain a more improved effect in preventing light leakage due to a horizontal current from the charge generating layer CGL.

In addition, although not specifically described in the specific contents and examples of the present invention, a bottom emission method in which the first electrode 110 is formed as a transmissive electrode having a transmittance of 80% or more and the second electrode 200 is formed as a reflective electrode In the organic light emitting diode display, light leakage defects can be prevented in the same manner as in the embodiment of the present invention, and thus the optical reliability of the organic light emitting display can be improved.

a plurality of light emitting units including an organic light emitting layer formed in the plurality of sub-pixel regions and the organic light emitting layer and disposed between the first electrode and the second electrode, and a charge generation layer disposed between the plurality of light emitting units, wherein the charge generation The layer is positioned in the plurality of sub-pixel areas and is an organic light-emitting device having a step difference at a boundary between the plurality of sub-pixel areas.

The organic emission layer may include a red emission layer, a green emission layer, and a blue emission layer.

The thickness of the red light emitting layer, the thickness of the green light emitting layer, and the thickness of the blue light emitting layer may be different from each other.

A thickness of the red light-emitting layer may be greater than a thickness of the green light-emitting layer, and a thickness of the green light-emitting layer may be greater than a thickness of the blue light-emitting layer.

The step difference of the charge generation layer may be 200 Å or more.

An organic light emitting layer disposed between the first electrode and the second electrode, the organic light emitting layer formed in red, green, and blue sub-pixel regions, the charge generating layer formed between the first electrode and the second electrode, and the organic light emitting layer, wherein the first electrode and a first light emitting unit formed between the charge generation layer and the organic light emitting layer, and a second light emitting unit formed between the charge generation layer and the second electrode, wherein the charge generation layer includes the red, green, It is characterized in that it is located in the blue sub-pixel region and is an organic light-emitting device having a step difference at the boundary between the red, green, and blue sub-pixel regions.

The organic emission layer may include a red emission layer, a green emission layer, and a blue emission layer.

A thickness of the red light emitting layer of the first light emitting unit may be greater than a thickness of the red light emitting layer of the second light emitting unit.

A thickness of the blue light emitting layer of the first light emitting unit may be smaller than a thickness of the blue light emitting layer of the second light emitting unit.

The thickness of the green light emitting layer of the first light emitting unit may be smaller than the thickness of the red light emitting layer of the first light emitting unit and greater than the thickness of the blue light emitting layer of the first light emitting unit.

A thickness of the red light emitting layer of the first light emitting unit may be smaller than a thickness of the red light emitting layer of the second light emitting unit.

A thickness of the blue light emitting layer of the first light emitting unit may be greater than a thickness of the blue light emitting layer of the second light emitting unit.

A thickness of the green light emitting layer of the first light emitting unit may be greater than a thickness of the red light emitting layer of the first light emitting unit and smaller than a thickness of the blue light emitting layer of the first light emitting unit.

An organic light emitting layer disposed between the first electrode and the second electrode, the organic light emitting layer formed in red, green, and blue sub-pixel regions, the charge generating layer formed between the first electrode and the second electrode, and the organic light emitting layer, wherein the first electrode and a first light emitting unit formed between the charge generation layer and the organic light emitting layer, wherein the second light emitting unit formed between the charge generation layer and the second electrode and the first light emitting unit are located below the organic light emitting layer a first hole transport layer and a second hole transport layer positioned below the organic light emitting layer of the second light emitting unit, wherein the charge generating layer is positioned in the red, green, and blue sub-pixel regions, red, green, It is characterized in that it is an organic light emitting device having a step difference at the boundary of the blue sub-pixel region.

The organic emission layer may include a red emission layer, a green emission layer, and a blue emission layer.

A thickness of the first hole transport layer in the green sub-pixel region may be smaller than a thickness of the first hole transport layer in the red sub-pixel region, and may be greater than a thickness of the first hole transport layer in the blue sub-pixel region. .

A thickness of the second hole transport layer in the green sub-pixel region may be greater than a thickness of the second hole transport layer in the red sub-pixel region and less than a thickness of the first hole transport layer in the blue sub-pixel region .

Although the embodiments of the present invention have been described in more detail with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and various modifications may be made within the scope without departing from the technical spirit of the present invention. . Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The protection scope of the present invention should be construed by the claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

10: substrate
11: electrode 1
12: electrode 2
13 : bank
14: organic layer
100A, 100B, 100C, 100D, 300: organic light emitting device
110, 310: first electrode (Anode)
120a, 120b, 120c, 120d, 320: hole injection layer (HIL)
130a, 130b, 130c, 130d, 330: first hole transport layer (1 ^st HTL)
140a, 140b, 140c, 140d, 340: first red light emitting layer (1 ^st Red EML)
141a, 141b, 141c, 141d, 341: first green light emitting layer (1 ^st Green EML)
142a, 142b, 142c, 142d, 342: first blue light emitting layer (1 ^st Blue EML)
150a, 150b, 150c, 150d, 350: first electron transport layer (1 ^st ETL)
160a, 160b, 160c, 160d, 360: charge generation layer (CGL)
170a, 170b, 170c, 170d, 370: second hole transport layer (2 ^nd HTL)
180a, 180b, 180c, 180d, 380: second red light emitting layer ( ^2nd Red EML)
181a, 181b, 181c, 181d, 381: second green light emitting layer (2 ^nd Green EML)
182a, 182b, 182c, 182d, 382: second blue light emitting layer (2 ^nd Blue EML)
190a, 190b, 190c, 190d, 390: second electron transport layer (2 ^nd ETL)
200, 400: second electrode (Cathode)
1100a, 1100b, 1100c, 1100d, 3100: first light emitting unit (1 ^st EL Unit)
1200a, 1200b, 1200c, 1200d, 3200: second light emitting unit ( ^2nd EL Unit)

Claims (20)

an organic light emitting layer disposed between the first electrode and the second electrode and disposed in the plurality of sub-pixel areas;
a plurality of light emitting units including the organic light emitting layer;
a charge generation layer positioned between the plurality of light emitting units;
a first hole transport layer positioned under the organic light emitting layer of one of the plurality of light emitting units; and
a second hole transport layer positioned under the organic light emitting layer of another second light emitting unit among the plurality of light emitting units,
the charge generation layer is located in the plurality of sub-pixel areas, and has a step difference at a boundary between the plurality of sub-pixel areas;
The organic light-emitting layer includes a red light-emitting layer, a green light-emitting layer, and a blue light-emitting layer,
The thickness of the red light-emitting layer, the thickness of the green light-emitting layer, and the thickness of the blue light-emitting layer are different from each other,
The thickness of the red light-emitting layer is greater than the thickness of the green light-emitting layer, the thickness of the green light-emitting layer is greater than the thickness of the blue light-emitting layer,
the plurality of sub-pixel areas include a red sub-pixel area, a green sub-pixel area, and a blue sub-pixel area;
and a thickness of the second hole transport layer in the blue sub-pixel region is greater than a thickness of the second hole transport layer in the green sub-pixel region. delete According to claim 1,
The step difference of the charge generation layer is 200 Å or more organic light emitting device. an organic light emitting layer disposed between the first electrode and the second electrode and disposed in the red, green, and blue sub-pixel regions;
a charge generation layer disposed between the first electrode and the second electrode;
a first light emitting unit including the organic light emitting layer and disposed between the first electrode and the charge generating layer;
a second light emitting unit including the organic light emitting layer and disposed between the charge generating layer and the second electrode;
a first hole transport layer positioned under the organic light emitting layer of the first light emitting unit; and
and a second hole transport layer positioned under the organic light emitting layer of the second light emitting unit,
the charge generation layer is positioned in the red, green, and blue sub-pixel regions and has a step difference at a boundary between the red, green, and blue sub-pixel regions;
The organic light emitting layer includes a red light emitting layer, a green light emitting layer, and a blue light emitting layer,
A thickness of the second hole transport layer in the green sub-pixel region is smaller than a thickness of the second hole transport layer in the red sub-pixel region. 5. The method of claim 4,
The step difference of the charge generation layer is 200 Å or more organic light emitting device. an organic light emitting layer disposed between the first electrode and the second electrode and disposed in the red, green, and blue sub-pixel regions;
a first light emitting unit and a second light emitting unit including the organic light emitting layer;
a charge generation layer positioned between the first light emitting unit and the second light emitting unit;
a first electron transport layer positioned on the organic light emitting layer of the first light emitting unit; and
a second electron transport layer positioned on the organic light emitting layer of the second light emitting unit;
The organic light-emitting layer includes a red light-emitting layer, a green light-emitting layer, and a blue light-emitting layer,
The thickness of the red light-emitting layer is greater than the thickness of the green light-emitting layer, the thickness of the green light-emitting layer is greater than the thickness of the blue light-emitting layer,
and a thickness of the first electron transport layer is different from a thickness of the second electron transport layer. 7. The method of claim 6,
The charge generating layer is positioned in the red, green, and blue sub-pixel regions, and has a step difference at a boundary between the red, green, and blue sub-pixel regions. an organic light emitting layer disposed between the first electrode and the second electrode and disposed in the red, green, and blue sub-pixel regions;
a first light emitting unit and a second light emitting unit including the organic light emitting layer;
a charge generation layer positioned between the first light emitting unit and the second light emitting unit;
a first hole transport layer positioned under the organic light emitting layer of the first light emitting unit; and
and a second hole transport layer positioned under the organic light emitting layer of the second light emitting unit,
a thickness of the second hole transport layer in the blue sub-pixel region is greater than a thickness of the second hole transport layer in the green sub-pixel region;
The organic light-emitting layer includes a red light-emitting layer, a green light-emitting layer, and a blue light-emitting layer,
A thickness of the red light emitting layer is greater than a thickness of the green light emitting layer, and a thickness of the green light emitting layer is greater than a thickness of the blue light emitting layer. an organic light emitting layer disposed between the first electrode and the second electrode and disposed in the red, green, and blue sub-pixel regions;
a first light emitting unit and a second light emitting unit including the organic light emitting layer;
a charge generation layer positioned between the first light emitting unit and the second light emitting unit;
a first hole transport layer positioned under the organic light emitting layer of the first light emitting unit; and
and a second hole transport layer positioned under the organic light emitting layer of the second light emitting unit,
a thickness of the first hole transport layer in the red sub-pixel region is different from a thickness of the second hole transport layer in the red sub-pixel region;
The organic light-emitting layer includes a red light-emitting layer, a green light-emitting layer, and a blue light-emitting layer,
A thickness of the red light emitting layer is greater than a thickness of the green light emitting layer, and a thickness of the green light emitting layer is greater than a thickness of the blue light emitting layer. 7. The method of claim 6,
a first hole transport layer positioned under the organic light emitting layer of the first light emitting unit; and
and a second hole transport layer positioned under the organic light emitting layer of the second light emitting unit,
and a thickness of the first hole transport layer in the green sub-pixel region is different from a thickness of the second hole transport layer in the green sub-pixel region. an organic light emitting layer disposed between the first electrode and the second electrode and disposed in the red, green, and blue sub-pixel regions;
a first light emitting unit and a second light emitting unit including the organic light emitting layer;
a charge generation layer positioned between the first light emitting unit and the second light emitting unit;
a first hole transport layer positioned under the organic light emitting layer of the first light emitting unit; and
and a second hole transport layer positioned under the organic light emitting layer of the second light emitting unit,
a thickness of the first hole transport layer in the blue sub-pixel region is different from a thickness of the second hole transport layer in the blue sub-pixel region;
The organic light-emitting layer includes a red light-emitting layer, a green light-emitting layer, and a blue light-emitting layer,
A thickness of the red light emitting layer is greater than a thickness of the green light emitting layer, and a thickness of the green light emitting layer is greater than a thickness of the blue light emitting layer. delete 7. The method of claim 6,
The thickness of the first electron transport layer is smaller than the thickness of the second electron transport layer, the organic light emitting device. an organic light emitting layer disposed between the first electrode and the second electrode and disposed in the red, green, and blue sub-pixel regions;
a first light emitting unit and a second light emitting unit including the organic light emitting layer; and
a first hole transport layer positioned under the organic light emitting layer of the first light emitting unit; and
and a second hole transport layer positioned under the organic light emitting layer of the second light emitting unit,
The organic light-emitting layer includes a red light-emitting layer, a green light-emitting layer, and a blue light-emitting layer,
The thickness of the red light-emitting layer, the thickness of the green light-emitting layer, and the thickness of the blue light-emitting layer are the same,
and a thickness of the first hole transport layer in the red sub-pixel region is different from a thickness of the second hole transport layer in the red sub-pixel region. 15. The method of claim 14,
and a thickness of the first hole transport layer in the blue sub-pixel region is different from a thickness of the second hole transport layer in the blue sub-pixel region. 16. The method of claim 15,
and a thickness of the first hole transport layer in the blue sub-pixel region is smaller than a thickness of the second hole transport layer in the blue sub-pixel region. 15. The method of claim 14,
and a thickness of the first hole transport layer in the green sub-pixel region is different from a thickness of the second hole transport layer in the green sub-pixel region. 15. The method of claim 14,
a first electron transport layer positioned on the organic light emitting layer of the first light emitting unit; and
a second electron transport layer positioned on the organic light emitting layer of the second light emitting unit;
and a thickness of the first electron transport layer is different from a thickness of the second electron transport layer. 19. The method of claim 18,
The thickness of the first electron transport layer is smaller than the thickness of the second electron transport layer, the organic light emitting device. 15. The method of claim 14,
and a charge generation layer positioned between the first light emitting unit and the second light emitting unit,
The charge generating layer is positioned in the red, green, and blue sub-pixel regions, and has a step difference at a boundary between the plurality of sub-pixel regions.

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