KR102299891B1 - Method for manufacturing organic light emitting device - Google Patents

Abstract

In the method of manufacturing an organic light emitting device according to an embodiment of the present invention, a P-type doped layer is formed on a donor substrate and then a P-type doped layer is formed between the first substrate and the organic light emitting layer through a laser thermal transfer method. It has the effect of compensating for non-uniform incomplete interfaces that may occur on the deposition surface.
In addition, the P-type doped layer of the organic light emitting device according to the embodiment of the present invention serves to allow holes to move well and to additionally generate holes, thereby reducing the interfacial stress of the organic light emitting device and preventing the increase of the driving voltage. There is an effect that can be done.
In addition, the organic light emitting device according to an embodiment of the present invention has an effect of improving the lifespan of the organic light emitting device by preventing an increase in the driving voltage.

Description

Method for manufacturing an organic light emitting device {METHOD FOR MANUFACTURING ORGANIC LIGHT EMITTING DEVICE}

The present invention relates to a method of manufacturing an organic light emitting device, and more particularly, to a method of manufacturing an organic light emitting device capable of driving at a low voltage and improving light emission lifetime.

An organic light emitting display (OLED) is a self-emitting display device, in which electrons and holes are injected into the light emitting layer from an electrode for electron injection and an electrode for hole injection, respectively. 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 includes a top emission type, a bottom emission type, a dual emission type, etc. depending on a direction in which light is emitted, and a passive matrix type according to a driving method. ) and active matrix type.

Unlike a liquid crystal display (LCD), the 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 display device is being researched as a next-generation display because it is advantageous in terms of power consumption due to low voltage driving and excellent in 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. In addition, there are problems in that the reliability of the organic light emitting diode decreases and power consumption increases due to an increase in applied current.

Accordingly, there is a need to overcome the technical limitations of improving the luminous efficiency, lifespan, and power consumption of the organic light emitting diode, which are factors that impede the quality and productivity of the organic light emitting display device. Furthermore, the demand for the development of an organic light emitting device capable of improving the luminous efficiency, the lifetime of the organic light emitting layer, and the viewing angle characteristics while maintaining the color gamut is also continuing.

The organic light emitting device according to the prior art has limitations in light emitting characteristics and lifespan performance due to the material and light emitting structure of the organic light emitting layer, and various methods for improving light emitting efficiency and lifespan have been proposed. However, there is a problem in that power consumption is consumed when the luminance is increased, and the luminous efficiency is lowered when the light emitting material is changed to secure a high lifespan.

A method of manufacturing an organic light emitting device through laser induced thermal printing is a hole injection layer (HIL), a hole transport layer (HTL) and an electron blocking layer ( EBL) is formed to correspond in common to the red sub-pixel region Red, the green sub-pixel region Green, and the blue sub-pixel region Blue, and an optical auxiliary layer and an organic layer formed on the donor substrate thereon This is performed by transferring the organic material layer including the light emitting layer (EML) to the receptor substrate through laser irradiation on the donor substrate.

However, in the case of performing the laser thermal transfer method as described above, a non-uniform imperfect interface exists between the deposition surface of the receptor substrate and the donor substrate, making it difficult to transfer holes, and thereby recombination of the organic light emitting layer A phenomenon in which the efficiency is lowered and the driving voltage is increased may occur due to the movement of the recombination zone.

As described above, when the driving voltage of the organic light emitting diode increases, the power consumption of the organic light emitting diode display increases. As deterioration occurs, there is a problem in that the lifespan of the organic light emitting diode is reduced.

An object to be solved according to an embodiment of the present invention is to provide a method of manufacturing an organic light emitting diode having improved driving and light emission lifespan at a low voltage.

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 method of manufacturing an organic light emitting device according to an embodiment of the present invention, there is provided a method of manufacturing an organic light emitting device capable of driving at a low voltage and improving light emission lifetime.

A method of manufacturing an organic light emitting diode according to an embodiment of the present invention includes the steps of preparing a first substrate, preparing a second substrate, aligning and bonding the first and second substrates, and applying a laser beam to the second substrate. and transferring the first organic material layer formed on the second substrate onto the first substrate by irradiating the light, and removing the second substrate, wherein preparing the second substrate comprises: a first organic light emitting layer on the second substrate; and sequentially forming a first organic material layer including the first optical auxiliary layer and the first P-type doping layer.

According to another feature of the present invention, preparing a third substrate, aligning and bonding the first substrate and the third substrate on which the first organic material layer is formed, and irradiating a laser to the third substrate to form the third substrate The method further includes transferring the second organic material layer onto the first substrate and removing the third substrate, wherein preparing the third substrate includes a second organic light emitting layer, a second optical auxiliary layer, and a second layer on the third substrate. The method may include sequentially forming a second organic material layer including the P-type doping layer.

According to another feature of the present invention, the step of preparing the first substrate comprises the steps of forming a first electrode on the first substrate and forming a hole injection layer, a hole transport layer and an electron blocking layer on the first electrode. It is characterized in that it further comprises.

According to another feature of the present invention, the steps of forming a third organic light emitting layer on the entire surface of the first substrate on which the first organic material layer and the second organic material layer are formed, forming an electron transport layer on the third organic light emitting layer, and on the electron transport layer The method may further include forming a second electrode and forming a capping layer on the second electrode.

According to another feature of the present invention, each of the second substrate and the third substrate may include a laser thermal transfer film.

According to another feature of the present invention, each of the first P-type doped layer and the second P-type doped layer may be formed by doping the hole transport layer material with a P-type dopant or may be formed of a P-type material.

According to another feature of the present invention, the first organic emission layer may include a red emission layer, and the second organic emission layer may include a green emission layer.

According to another feature of the present invention, the first P-type doped layer and the second P-type doped layer may be formed to have different thicknesses.

According to another feature of the present invention, the first P-type doped layer and the second P-type doped layer may have different dopant concentrations.

According to another feature of the present invention, the third organic light emitting layer may be formed of a blue light emitting layer.

According to another feature of the present invention, the first optical auxiliary layer and the second optical auxiliary layer may be formed to have different thicknesses.

In the method of manufacturing an organic light emitting device according to an embodiment of the present invention, after forming a P-type doping layer on a donor substrate, a P-type doping layer is formed between the first substrate and the organic light emitting layer through laser thermal transfer. It has the effect of compensating for non-uniform incomplete interfaces that may occur on the deposition surface during the thermal transfer process.

In addition, the P-type doped layer of the organic light emitting device according to the embodiment of the present invention serves to allow holes to move well and to additionally generate holes, thereby reducing the interfacial stress of the organic light emitting device and preventing the increase of the driving voltage. There is an effect that can be done.

In addition, the organic light emitting device according to an embodiment of the present invention has an effect of improving the lifespan of the organic light emitting device by preventing an increase in the driving voltage.

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 flowchart illustrating a method of manufacturing an organic light emitting device according to an embodiment of the present invention.
2(a) to 2(e) are schematic cross-sectional views illustrating a method of manufacturing an organic light emitting device according to an exemplary embodiment of the present invention.
3A to 3D are schematic cross-sectional views illustrating a method of manufacturing an organic light emitting diode according to an exemplary embodiment of the present invention.
4(a) to 4(c) are schematic cross-sectional views illustrating a method of manufacturing an organic light emitting diode according to an exemplary embodiment of the present invention.
5(a) to 5(d) are schematic cross-sectional views illustrating a method of manufacturing an organic light emitting diode according to an exemplary embodiment of the present invention.
6(a) to 6(c) are schematic cross-sectional views illustrating a method of manufacturing an organic light emitting diode according to an exemplary embodiment of the present invention.
7(a) to 7(d) are schematic cross-sectional views illustrating a method of manufacturing an organic light emitting diode according to an exemplary embodiment of the present invention.
8 is a view illustrating electro-optical characteristic evaluation results during red light emission and green light emission of an organic light emitting diode according to an embodiment of the present invention and an organic light emitting diode according to a comparative example.
9A and 9B are diagrams illustrating evaluation results of lifespan characteristics during red light emission and green light emission of an organic light emitting diode according to an embodiment of the present invention and an organic light emitting diode according to a comparative example.

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 implemented 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 subject matter 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 interpreted 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 the 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 may be partially or wholly combined or combined with each other, technically various interlocking and driving are possible, and each of the embodiments may be implemented independently of each other or may be implemented together in a related relationship. may be

1 is a flowchart illustrating a method of manufacturing an organic light emitting device according to an embodiment of the present invention.

Also, FIGS. 2 to 7 are schematic cross-sectional views illustrating a method of manufacturing an organic light emitting diode according to an exemplary embodiment of the present invention.

Hereinafter, a method of manufacturing an organic light emitting diode according to an exemplary embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2 to 7 .

Laser Induced Thermal Printing is a method of forming a pattern by converting a laser emitted from a light source into thermal energy and transferring a pattern-forming material to a target substrate by this thermal energy. A pattern-forming material formed on a laser thermal transfer film A donor substrate comprising a, a receptor substrate onto which a pattern forming material is transferred, and a laser light source are required.

When performing the laser thermal transfer method, the donor substrate is bonded to and fixed to the receptor substrate on the optical stage while covering the entirety of the receptor substrate. Then, the optical system moves on the donor substrate, and a laser beam is irradiated from the light source in the optical system to the donor substrate to transfer the pattern forming material to the receptor substrate to form a pattern.

1 and 2 (a) to 2 (e), the steps of preparing the first substrate 205 (S101 to S104) are started.

First, finally, the substrate 200 on which the organic light emitting device according to the embodiment of the present invention is formed is prepared. The first substrate 205 described in the embodiment of the present invention refers to the receptor substrate described above in the laser thermal transfer method.

The substrate 200 may be made of a material of glass, plastic, quartz, silicon, or metal, and may also be made of a transparent material.

1 and 2 (b), a first electrode 201 (anode) is formed on the substrate 200 (S101). The first electrode 201 is formed to correspond to all of the red sub-pixel region Rp, the green sub-pixel region Gp, and the blue sub-pixel region Bp. The first electrode 201 may be formed as a reflective electrode, for example, a layer of a transparent conductive material having a high work function, such as indium-tin-oxide (ITO), and silver (Ag) or silver. It may include a layer of a reflective material such as an Ag alloy.

Next, referring to FIGS. 1 and 2C , a hole injection layer 202 (HIL) is formed on the first electrode 201 ( S102 ). The hole injection layer 202 is formed on the first electrode 201 to correspond to all of the red sub-pixel region Rp, the green sub-pixel region Gp, and the blue sub-pixel region Bp.

The hole injection layer 202 may serve to facilitate hole injection, and may include HATCN and cupper phthalocyanine (CuPc), poly(3,4)-ethylenedioxythiophene (PEDOT), polyaniline (PANI), and N,N (N,N). -dinaphthyl-N,N'-diphenylbenzidine) may consist of any one or more selected from the group consisting of, but is not limited thereto.

Next, referring to FIGS. 1 and 2D , a hole transporting layer (HTL) 203 is formed on the hole injection layer 202 ( S103 ). The hole transport layer 203 serves to facilitate hole transport, and includes N,N-dinaphthyl-N,N'-diphenylbenzidine (NPD), N,N'-bis-(3-methylphenyl)-N (TPD), Any one selected from the group consisting of N'-bis-(phenyl)-benzidine), s-TAD and MTDATA (4,4',4"-Tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine) It may be made as above, but is not limited thereto.

Next, referring to FIGS. 1 and 2 (e), an electron blocking layer 204 (electron blocking layer: EBL) is formed on the hole transport layer 203 (S104). The electron blocking layer 204 prevents electrons from moving to the hole transport layer 203 to facilitate recombination of holes and electrons in the organic light emitting layer, thereby improving the luminous efficiency of the organic light emitting diode.

Through the above steps, the first substrate 205 in which the first electrode 201 , the hole injection layer 202 , the hole transport layer 203 , and the electron blocking layer 204 are sequentially formed on the substrate 200 is prepared .

Next, referring to FIGS. 1 and 3 ( a ) to 3 ( d ), the steps of preparing the second substrate 315 ( S111 to S114 ) are started. The second substrate 315 described in the embodiment of the present invention refers to the first donor substrate described above in the laser thermal transfer method.

1 and 3 (a), a first laser thermal transfer film 311 is prepared (S111). The first laser thermal transfer film 311 is transparent in order to transmit light to the thermal conversion layer, and may be made of a material having suitable optical properties and sufficient mechanical stability. For example, the base film of the first laser thermal transfer film 311 is polyester, polyacryl, polyepoxy, polyethylene, and polyethyleneterephthalate and polystyrene (polyethyleneterephthalate). It may be made of one or more polymer materials or glass selected from the group consisting of polystyrene).

In addition, a heat conversion layer may be additionally formed between the base film and the pattern forming material. The heat conversion layer is a layer that converts a portion of the light into heat by absorbing light in the infrared to visible ray region, and may include a light absorbing material to absorb light.

The heat conversion layer may be made of a metal material made of aluminum (Al), silver (Ag), oxides and sulfides thereof, or an organic material made of a polymer including carbon black, graphite, or infrared dye.

Next, referring to FIGS. 1 and 3B , a first organic emission layer 312 is formed on the first laser thermal transfer film 311 ( S112 ). In an embodiment of the present invention, the first organic emission layer 312 may be formed of a red emission layer (Red EML) that emits red light.

The first organic emission layer 312 includes a host material including carbazole biphenyl (CBP) or 1,3-bis (carbazol-9-yl) (mCP), and PIQIr (acac) (bis (1-phenylisoquinoline) acetylacetonate iridium ), PQIr (acac) (bis (1-phenylquinoline) acetylacetonate iridium), PQIr (tris (1-phenylquinoline) iridium) and PtOEP (octaethylporphyrin platinum) phosphorescent material comprising a dopant comprising at least one selected from the group consisting of Alternatively, it may be made of a fluorescent material including PBD:Eu(DBM)3(Phen) or Perylene, but is not limited thereto.

Next, referring to FIGS. 1 and 3C , a first optical auxiliary layer 313 is formed on the first organic emission layer 312 ( S113 ). The first optical auxiliary layer 313 serves as a first R-hole transporting layer (R-HTL) formed in the red sub-pixel region Rp, and is formed in the red sub-pixel region Rp to form micro It is possible to form the optical distance of the cavity (micro cavity).

The first optical auxiliary layer 313 serves to facilitate hole transport, and includes N,N-dinaphthyl-N,N'-diphenylbenzidine (NPD), N,N'-bis-(3-methylphenyl) NPD (N,N'-bis-(3-methylphenyl) In the group consisting of -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, but is not limited thereto.

Next, referring to FIGS. 1 and 3D , a first P-type doped layer 314 ( ^1st p-doped layer) is formed on the first optical auxiliary layer 313 ( S114 ). The first P-type doped layer 314 is formed on the deposition surface between the first substrate 205, which is a receptor substrate, and the second substrate 315, which is the first donor substrate. It acts as an interlayer that complements the (imperfect interface), and can serve to not only induce holes to move well, but also to create additional holes.

The first P-type doped layer 314 is formed by doping the material of the hole injection layer 202, the hole transport layer 203, or the first optical auxiliary layer 313 described above with a P-type dopant, or P It may be formed of a mold material.

The first P-type doped layer 314 may be formed to a thickness of 1 or more and 400 Å or less in consideration of the formation of an optical distance suitable for characteristics of the organic light emitting device., the hole injection layer 202, the hole transport layer 203, or When the first P-type dopant is doped into the material of the first optical auxiliary layer 313 to form the first P-type doped layer 314 , the concentration of the P-type dopant is preferably 0.1 or more and 10% or less.

Through the above steps, the first organic material layer including the first organic light emitting layer 312 , the first optical auxiliary layer 313 , and the first P-type doping layer 314 on the first laser thermal transfer film 311 . The sequentially formed second substrates 315 are prepared.

Next, referring to FIGS. 1 and 4( a ) to 4( c ), bonding and transferring the first substrate 205 and the second substrate 315 ( S131 to S133 ) are started.

First, referring to FIGS. 1 and 4( a ), the second substrate 315 is aligned to correspond to the front surface of the first substrate 205 and adhered to the first substrate 205 ( S131 ).

Next, referring to FIGS. 1 and 4B , the first P-type first P-type film 311 is irradiated with a laser beam corresponding to the red sub-pixel region Rp of the second substrate 315 . The doped layer 314 , the first optical auxiliary layer 313 , and the first organic emission layer 312 are transferred onto the electron blocking layer 204 formed on the first substrate 205 ( S132 ). At this time, the first P-type doping layer 314 , the first optical auxiliary layer 313 , and the first organic emission layer 312 only on the electron blocking layer 204 of the red sub-pixel region Rp to which the laser is selectively irradiated. It is transferred and formed.

Next, referring to FIGS. 1 and 4 ( c ), the first P-type doping layer 314 , the first optical auxiliary layer 313 , and the first organic light emitting layer 312 are applied to the electrons of the first substrate 205 . After the transfer on the blocking layer 204, the first laser thermal transfer film 311 is removed (S133). As shown in FIG. 4C , when the first laser thermal transfer film 311 is removed, the organic material layer formed in the region other than the red sub-pixel region Rp is formed at the same time as the first laser thermal transfer film 311 . are removed together

Through the above steps, in the red sub-pixel region Rp of the first substrate 205, the first P-type doped layer 314, the first optical auxiliary layer 313, and the first organic emission layer ( 312) is completed.

Next, referring to FIGS. 1 and 5 ( a ) to 5 ( d ), the steps of preparing the third substrate 425 ( S121 to S124 ) are started. The third substrate 425 described in the embodiment of the present invention refers to the second donor substrate described above in the laser thermal transfer method.

In describing this step, a description of the same or corresponding components to the previously described steps will be omitted.

Referring to FIGS. 1 and 5 ( a ), first, a second laser thermal transfer film 421 is prepared ( S121 ). The second laser thermal transfer film 421 is transparent in order to transmit light to the thermal conversion layer, and may be made of a material having suitable optical properties and sufficient mechanical stability. For example, the base film of the second laser thermal transfer film 421 may include polyester, polyacryl, polyepoxy, polyethylene, and polyethyleneterephthalate and polystyrene (polyethyleneterephthalate). It may be made of one or more polymer materials or glass selected from the group consisting of polystyrene).

Next, referring to FIGS. 1 and 5B , a second organic emission layer 422 is formed on the second laser thermal transfer film 421 ( S122 ). In an embodiment of the present invention, the second organic emission layer 422 may be formed of a green emission layer (Green EML) emitting green light.

The second organic emission layer 422 includes a host material including CBP or mCP, and a phosphorescent material including a dopant material such as Ir complex including Ir(ppy)3 (fac tris(2-phenylpyridine)iridium). Alternatively, it may be made of a fluorescent material including Alq3 (tris(8-hydroxyquinolino)aluminum), but is not limited thereto.

Next, referring to FIGS. 1 and 5C , a second optical auxiliary layer 423 is formed on the second organic emission layer 422 ( S123 ). The second optical auxiliary layer 423 serves as a second hole transporting layer (G-HTL) formed in the green sub-pixel region Gp, and is formed in the green sub-pixel region Gp to form micro The optical distance of the cavity can be formed. As described above, when considering the formation of an optical distance in the red sub-pixel region Rp and the green sub-pixel region Gp, the thicknesses of the first optical auxiliary layer 313 and the second optical auxiliary layer 423 are different from each other. can

The second optical auxiliary layer 423 serves to facilitate hole transport, and includes N,N-dinaphthyl-N,N'-diphenylbenzidine (NPD), N,N'-bis-(3-methylphenyl) NPD (N,N'-bis-(3-methylphenyl) In the group consisting of -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, but is not limited thereto.

To form the following, Fig. 1 and to FIG. 5 (d), the second optical auxiliary layer 423, the second P-type doped layers (424, 2 ^nd p-doped layer) on a (S124). The second P-type doping layer 424 is formed on the deposition surface between the first substrate 205 serving as the receptor substrate and the third substrate 425 serving as the second donor substrate, so that a non-uniform incomplete interface that may occur on the deposition surface is formed. It acts as an interlayer that complements the (imperfect interface), and can serve to not only induce holes to move well, but also to create additional holes.

The second P-type doped layer 424 is formed by doping the above-described material of the hole injection layer 202, the hole transport layer 203, or the second optical auxiliary layer 423 with a P-type dopant, or P It may be formed of a mold material.

The second P-type doped layer 424 may be formed to a thickness of 1 or more and 400 Å or less in consideration of the formation of an optical distance suitable for characteristics of the organic light emitting device. When the second P-type doped layer 424 is formed by doping the P-type dopant into the material of the hole injection layer 202 , the hole transport layer 203 , or the second optical auxiliary layer 423 , the concentration of the P-type dopant is 0.1 A level of 10% or more is preferable.

In addition, when considering the formation of an optical distance in the red sub-pixel region Rp and the green sub-pixel region Gp, the thickness of the first P-type doped layer 314 and the second P-type doped layer 424 is different from each other. The dopant concentration of the first P-type doped layer 314 and the second P-type doped layer 424 may be different from each other.

Through the above steps, a second organic material layer including a second organic light emitting layer 422 , a second optical auxiliary layer 423 , and a second P-type doping layer 424 on the second laser thermal transfer film 421 . The sequentially formed third substrate 425 is prepared.

Next, referring to FIGS. 1 and 6(a) to 6(c) , bonding and transferring the first substrate 205 and the third substrate 425 ( S141 to S143 ) are started.

First, referring to FIGS. 1 and 6A , the third substrate 425 is aligned to correspond to the front surface of the first substrate 205 and adhered to the first substrate 205 ( S141 ).

Next, referring to FIGS. 1 and 6B , the second P-type film 421 is irradiated with a laser beam corresponding to the green sub-pixel region Gp of the third substrate 425 . The doping layer 424 , the second optical auxiliary layer 423 , and the second organic emission layer 422 are transferred onto the electron blocking layer 204 formed on the first substrate 205 ( S142 ). At this time, the second P-type doping layer 424 , the second optical auxiliary layer 423 and the second organic emission layer 422 only on the electron blocking layer 204 of the green sub-pixel region Gp to which the laser is selectively irradiated. It is transferred and formed.

Next, referring to FIGS. 1 and 6 ( c ), the second P-type doping layer 424 , the second optical auxiliary layer 423 , and the second organic light emitting layer 422 are applied to the electrons of the first substrate 205 . After the transfer on the blocking layer 204, the second laser thermal transfer film 421 is removed (S143). As can be seen in FIG. 6(c) , when the second laser thermal transfer film 421 is removed, the organic material layer formed in the region other than the green sub-pixel region Gp is formed with the second laser thermal transfer film 421 and removed together at the same time.

Through the above steps, in the green sub-pixel region Gp of the first substrate 205, the second P-type doping layer 424, the second optical auxiliary layer 423, and the second organic emission layer ( 422) is completed.

Next, referring to FIGS. 1 and 7A to 7D , the first P-type doping layer 314 and the first optical auxiliary layer are formed in the red sub-pixel region Rp through the laser thermal transfer. 313 and the first organic emission layer 312 and the first organic emission layer 422 in which the second P-type doping layer 424 , the second optical auxiliary layer 423 and the second organic emission layer 422 are formed in the green sub-pixel region Gp A third organic emission layer 751 is formed on the substrate 205 ( S151 ).

The third organic emission layer 751 may be formed of a blue emission layer (Blue EML) emitting blue light. The third organic emission layer 751 is formed on the first organic emission layer 312 and the second organic emission layer 422 , and includes a red sub-pixel region Rp, a green sub-pixel region Gp, and a blue sub-pixel region ( It is formed so as to correspond to the front surface of Bp).

The third organic emission layer 751 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. Alternatively, it may be made of a fluorescent material including any one selected from the group consisting of spiro-DPVBi, spiro-6P, distylbenzene (DSB), distrylarylene (DSA), PFO-based polymers and PPV-based polymers. not limited

Next, referring to FIGS. 1 and 7B , an electron transporting layer (ETL) 752 is formed on the third organic emission layer 751 ( S152 ).

The electron transport layer 752 may play a role of electron transport and injection, and the thickness of the electron transport layer 752 may be adjusted in consideration of electron transport characteristics.

The electron transport layer 752 serves to facilitate the transport of electrons, and Alq3 (tris(8-hydroxyquinolino)aluminum), PBD, TAZ, spiro-PBD, BAlq, Liq(lithium quinolate), BMB-3T , PF-6P, TPBI, COT, and may be made of any one or more selected from the group consisting of SAlq, but is not limited thereto.

In addition, although not shown in the drawings, an electron injection layer (EIL) may be separately additionally formed on the electron transport layer 752 .

The electron injection layer (EIL) may include, but is not limited to, Alq3 (tris(8-hydroxyquinolino)aluminum), PBD, TAZ, spiro-PBD, BAlq, or SAlq.

Here, the structure is not limited according to the embodiment of the present invention, and the hole injection layer 202 , the hole transport layer 203 , the first optical auxiliary layer 313 , the second optical auxiliary layer 423 , and the electron transport layer At least one of (752) may be omitted.

In addition, the hole injection layer 202 , the hole transport layer 203 , the first optical auxiliary layer 313 , the second optical auxiliary layer 423 , the electron transport layer 752 , and the electron injection layer (EIL) are formed in two or more layers. It is also possible to configure as

Next, referring to FIGS. 1 and 7C , a second electrode 753 (cathode) is formed on the electron transport layer 752 (S153). The second electrode 753 may be made of, for example, silver (Ag) or an alloy of silver (Ag) and magnesium (Mg) (Ag:Mg), but is not limited thereto, and may have a transflective property.

That is, the light emitted from the organic emission layer is displayed to the outside through the second electrode 753 , and since the second electrode 753 has a transflective property, some light is directed back to the first electrode 201 . .

In this way, repeated reflection occurs between the first electrode 201 and the second electrode 753 acting as a reflective layer, and the first electrode 201 and the second electrode are caused by the micro-cavity effect. The light is repeatedly reflected in the cavity between 753 and the light efficiency is increased.

In addition, light from the organic light emitting layer may be externally displayed through the first electrode 201 by forming the first electrode 201 as a transmissive electrode and forming the second electrode 753 as a reflective electrode.

Next, referring to FIGS. 1 and 7D , a capping layer 754 (CPL) is formed on the second electrode 753 ( S154 ). The capping layer 754 is used to increase the light extraction effect, and the capping layer 754 includes a hole transport layer 203 material, a first optical auxiliary layer 313 material, a second optical auxiliary layer 423 material, and an electron transport layer. The material (752) and a host material of the first emission layer 312 , the second emission layer 412 , and the third emission layer 751 may be formed. It is also possible to omit the capping layer 754 .

Through the above manufacturing method, the organic light emitting device according to the embodiment of the present invention using the laser thermal transfer method is manufactured.

8 is a view showing electro-optical characteristic evaluation results in red light emission and green light emission of the organic light emitting diode according to the embodiment of the present invention and the organic light emitting diode according to the comparative example.

Referring to FIG. 8 , the organic light emitting diode of Comparative Example to which the P-type doping layer is not applied exhibited a driving voltage of 5.4 V and a luminance of 44.5 cd/A in the case of red light emission. On the other hand, the organic light emitting diode of the embodiment to which the P-type doping layer is applied exhibited a driving voltage of 4.4 V and a luminance of 46 cd/A in the case of red light emission.

That is, the organic light emitting device to which the P-type doped layer according to the embodiment of the present invention is applied exhibited a similar level of luminance when emitting red light, compared to the organic light emitting device of the Comparative Example to which the P-type doped layer was not applied. About 1.0V lower driving voltage was shown. From these results, it was confirmed that when the organic light-emitting device to which the P-type doping layer according to the embodiment of the present invention is applied is used, the effect of reducing the driving voltage can be obtained.

In addition, the organic light emitting diode of Comparative Example to which the P-type doping layer was not applied exhibited a driving voltage of 4.7 V and a luminance of 113.3 cd/A in the case of green light emission. On the other hand, the organic light emitting diode of the embodiment to which the P-type doping layer is applied exhibited a driving voltage of 4.3 V and a luminance of 115 cd/A in the case of green light emission.

That is, the organic light emitting device to which the P-type doping layer is applied according to the embodiment of the present invention exhibits a similar level of luminance when compared to the organic light emitting device of the Comparative Example to which the P-type doping layer is not applied when green light is emitted. About 0.4V lower driving voltage was shown. From these results, it was confirmed once again that when the organic light-emitting device to which the P-type doping layer is applied according to the embodiment of the present invention is used, the effect of reducing the driving voltage can be obtained.

9A and 9B are views showing results of evaluation of lifespan characteristics during red light emission and green light emission of an organic light emitting diode according to an embodiment of the present invention and an organic light emitting diode according to a comparative example.

Referring to the results of evaluation of the lifespan characteristics of the organic light emitting device with reference to FIGS. 8 and 9A , the lifespan of the organic light emitting device according to the comparative example was about 325 hours during red light emission, but the organic light emitting diode according to the embodiment of the present invention The lifetime of the device was about 425 hours. From these results, it was confirmed that, when the organic light emitting device according to the embodiment of the present invention is used, it is possible to achieve a lifespan improvement of about 100 hours during red light emission.

In addition, referring to FIGS. 8 and 9B , when looking at the evaluation results of the lifespan characteristics of the organic light emitting diode, the life of the organic light emitting diode according to the comparative example was about 200 hours when green light was emitted. The lifetime of the organic light emitting device was about 290 hours. From these results, it was confirmed that, when the organic light emitting diode according to the embodiment of the present invention is used, the lifespan improvement of about 90 hours can be achieved even when green light is emitted.

Combining the electro-optical evaluation and lifespan characteristic evaluation results, the organic light-emitting device according to the embodiment of the present invention to which the P-type doping layer is applied has the same level in the same color coordinates when compared to the organic light-emitting device of the comparative example, in the case of red light emission. The above efficiency, 31% lifespan improvement, and 1.0V level reduction in driving voltage were exhibited. In the case of green light emission, at the same color coordinate, efficiency above the same level, lifespan improvement of 45%, and driving voltage of 0.4V level It can be seen that it is possible to obtain the effect of reduction.

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.

200: substrate
201: first electrode
202: hole injection layer
203: hole transport layer
204: electron blocking layer
314: first P-type doped layer
424: second P-type doped layer
313: first optical auxiliary layer
423: second optical auxiliary layer
312: first organic light emitting layer
422: second organic light emitting layer
751: third organic light emitting layer
752: electron transport layer
753: second electrode
754: capping layer
205: first substrate
315: second substrate
425: third substrate

Claims (11)

preparing a first substrate;
preparing a second substrate;
aligning and bonding the first substrate and the second substrate;
transferring a first organic material layer formed on the second substrate onto the first substrate by irradiating a laser to the second substrate; and
removing the second substrate;
The step of preparing the first substrate,
forming a first electrode on a substrate; and
Comprising the step of forming a hole injection layer, a hole transport layer and an electron blocking layer on the first electrode,
The step of preparing the second substrate,
and sequentially forming the first organic material layer including a first organic light emitting layer, a first optical auxiliary layer, and a first P-type doping layer on the second substrate,
In the step of transferring the first organic material layer formed on the second substrate on the first substrate,
An organic light emitting device for transferring the first organic material layer of the second substrate onto the electron blocking layer of the first substrate to form the first P-type doped layer between the electron blocking layer and the first optical auxiliary layer manufacturing method. The method of claim 1,
preparing a third substrate;
aligning and bonding the first substrate and the third substrate on which the first organic material layer is formed;
transferring a second organic material layer formed on the third substrate onto the first substrate by irradiating a laser to the third substrate; and
Further comprising the step of removing the third substrate,
The step of preparing the third substrate,
and sequentially forming the second organic material layer including a second organic light emitting layer, a second optical auxiliary layer, and a second P-type doping layer on the third substrate. delete 3. The method of claim 2,
forming a third organic light emitting layer on the entire surface of the first substrate on which the first organic material layer and the second organic material layer are formed;
forming an electron transport layer on the third organic light emitting layer;
forming a second electrode on the electron transport layer; and
The method of manufacturing an organic light-emitting device further comprising the step of forming a capping layer on the second electrode. 3. The method of claim 2,
Each of the second substrate and the third substrate includes a laser thermal transfer film. 6. The method of claim 5,
Each of the first P-type doped layer and the second P-type doped layer is formed by doping the hole transport layer material with a P-type dopant or is formed of a P-type material. 7. The method of claim 6,
The method of manufacturing an organic light emitting device, wherein the first organic light emitting layer is made of a red light emitting layer, and the second organic light emitting layer is made of a green light emitting layer. 3. The method of claim 2,
The method of manufacturing an organic light emitting device in which the first P-type doped layer and the second P-type doped layer are formed to have different thicknesses. 7. The method of claim 6,
The method of manufacturing an organic light emitting device comprising the first P-type doped layer and the second P-type doped layer having different dopant concentrations. 5. The method of claim 4,
The third organic light emitting layer is a method of manufacturing an organic light emitting device comprising a blue light emitting layer. 3. The method of claim 2,
The method of manufacturing an organic light emitting device in which the first optical auxiliary layer and the second optical auxiliary layer are formed to have different thicknesses.

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