KR100786469B1 - Organic light-emitting device and the preparing method of the same - Google Patents

Abstract

The present invention relates to an organic light emitting device and a method of manufacturing the same, and more particularly, to an organic light emitting device and a method for manufacturing the organic light emitting device configured to prevent the light emitted from the organic layer is absorbed into a variety of layers, such as a substrate to reduce the light efficiency. An embodiment of the present invention provides an organic light emitting device comprising a substrate, a first electrode formed on the substrate, an organic layer formed on the first electrode, and a second electrode formed on the organic layer. Projections and / or recesses of a different material from the substrate are formed on the substrate in the direction of the organic layer, and the light efficiency is increased by refracting or re-reflecting light guided to the side of each layer.

Organic light emitting device, waveguide, refraction, light efficiency

Description

Organic light emitting device and its manufacturing method {Organic light-emitting device and the preparing method of the same}

1A is a cross-sectional view of an organic light emitting diode according to a first embodiment of the present invention.

1B is a plan view of an organic light emitting diode according to a first embodiment of the present invention.

1C is a cross-sectional view of an active organic light emitting diode to which a first embodiment of the present invention is applied.

2A is a cross-sectional view of an organic light emitting diode according to a second embodiment of the present invention.

Figure 2b is a cross-sectional view of the organic light emitting device to which the second embodiment of the present invention is applied.

3A is a cross-sectional view of an organic light emitting diode according to a second embodiment of the present invention.

3B is a cross-sectional view of an active organic light emitting diode to which a second embodiment of the present invention is applied.

<Description of the symbols for the main parts of the drawings>

10: substrate # 11: protrusion

12: first electrode 13: organic layer

14: second electrode 15: TR layer

16: TR layer # 20: substrate

21: first electrode 22: organic layer

23: second electrode 24: protective layer

25: TR floor # 26: recessed part

30 substrate: 31 filling material

32: first electrode 33: organic layer

34: second electrode 35: protective layer

36: TR floor

The present invention relates to an organic light emitting device and a method of manufacturing the same, and more particularly, to an organic light emitting device and a method for manufacturing the organic light emitting device configured to efficiently prevent light emitted from the organic layer is absorbed into a variety of layers, such as a substrate to lower the light efficiency will be.

An organic light emitting diode typically has a structure in which a substrate, a first electrode, an organic layer, and a second electrode are sequentially stacked. When an electric power is applied, carriers move from both electrodes to the organic layer to generate excitons in the organic layer. The device is configured to emit light when the excitons become the ground state.

Since light generated in the organic layer of a conventional organic light emitting device is Lambertian, light is emitted in the same direction in all directions, so that some light is reflected back to the device, and some light is emitted to the side and captured by the device. Etc., about 80% is lost, so that only 20% of the generated light is emitted substantially outside the device.

Therefore, various methods have been studied to improve the luminous efficiency of the organic light emitting device. U.S. Patent No. 5,834,893 describes the use of reflective structures surrounding light emitting regions or pixels and the use of angled or inclined reflecting walls at the edges of each pixel, and U.S. Patent No. 6,091,195 having an inclined wall. The pixel is described. However, as it moves laterally through parallel layers within a single pixel or light emitting area, a significant amount of light is still absorbed and lost. In addition, U.S. Patent Application Publication No. 2004-0070335, Japanese Patent Application Publication No. 2002-00360283 and the like disclose a technique of increasing light efficiency by forming an optical waveguide and reflecting light leaking out to the front.

However, even in the case of the organic light emitting device that emits back light by the above-described technology, there is a problem in that the loss of light leaking to the side through the substrate cannot be overcome.

The present invention has been made to solve the above problems, an object of the present invention is to form a phase portion of a predetermined structure on the substrate is not emitted or re-reflected light generated by the emission of the back light emitting structure of the organic light emitting structure is increased It is an object to provide a light emitting element.

An embodiment of the present invention provides an organic light emitting device comprising a substrate, a first electrode formed on the substrate, an organic layer formed on the first electrode, and a second electrode formed on the organic layer. Protruding portions of a material different from the substrate are formed on the substrate in the organic layer direction, and the protruding portions are formed along the curvature of the protruding portions of the first electrode, the organic layer, and the second electrode.

Further, another embodiment of the present invention is to provide a substrate, forming a first electrode formed on the substrate, forming an organic layer formed on the first electrode, and formed on the organic layer A method of manufacturing an organic light emitting device, the method comprising: forming a second electrode, the method comprising: forming a protrusion of a material different from the substrate in a direction of the organic layer on a substrate provided after providing the substrate; It is done.

In still another embodiment, an organic light emitting device includes a substrate, a first electrode formed on the substrate, an organic layer formed on the first electrode, and a second electrode formed on the organic layer. The recess may be formed on the substrate, and the first electrode, the organic layer, and the second electrode may be recessed along the curvature of the recess.

Further, another embodiment of the present invention is to provide a substrate, forming a first electrode formed on the substrate, forming an organic layer formed on the first electrode, and forming on the organic layer In the method of manufacturing an organic light emitting device comprising the step of forming a second electrode, characterized in that it comprises a step of forming a recess groove on the substrate provided after the step of providing the substrate.

In still another embodiment, an organic light emitting device includes a substrate, a first electrode formed on the substrate, an organic layer formed on the first electrode, and a second electrode formed on the organic layer. The concave portion is formed on the substrate, and the concave portion is filled with a filler of a material different from that of the substrate, and the first electrode is formed in an area on the substrate on which the concave portion is not formed. The electrode is characterized in that the bending portion is formed in accordance with the bending of the first electrode.

Further, another embodiment of the present invention is to provide a substrate, forming a first electrode formed on the substrate, forming an organic layer formed on the first electrode, and forming on the organic layer In the method of manufacturing an organic light emitting device comprising the step of forming a second electrode, after the step of providing the substrate, forming a recessed portion on the provided substrate, the recessed portion is filled with a filler of a different material than the substrate Characterized in that it comprises a step.

Hereinafter, a first preferred embodiment of the present invention will be described in detail with reference to FIG. 1A. 1A is a cross-sectional view of a bottom emission organic light emitting diode according to a first embodiment of the present invention. Accordingly, the organic light emitting diode includes a substrate 10, a protrusion 11, a first electrode 12, an organic layer 13, a second electrode 14, and a protective layer 15.

The substrate 10 may be a transparent glass material or the like for back emission as an insulating substrate. The substrate is provided in a conventional manner.

The protrusions 11 are formed of a material different from that of the substrate 10. The protrusions 11 are formed to have different refractive indices of the substrate 10 and the protrusions 11 so that light generated from the organic layer is formed on the side surface of the substrate 10 as one waveguide layer. This is to cause more reflection or refraction to occur without being guided by the light, so that light is emitted to the outside of the substrate 10. As the material of the protrusion 11, for example, SiNx, Ta 2 O 5, TiO 2, MgF 2, MgO, Al 2 O 3, CaO, or the like, but a material different from the refractive index of the substrate may be used, but is not limited thereto.

In the method of forming the protrusions 11 on the substrate 10, a material layer constituting the protrusions 11 is formed on the substrate, and then an etching method using conventional lithography means is used or a film such as PVA is used. A pressure sensitive adhesive may be applied to form a protrusion material thereon, the protrusion may be shaped by etching using conventional lithographic means, and then some or all of the substrate upper layer may be formed by a transfer method by applying an adhesive.

The protrusions 11 are preferably formed on the substrate in a shape that is sharpened toward the opposite direction of the substrate 10. When the angle is maintained at about 45 °, a constant luminance is obtained over a wide viewing angle range, 20 to 60 degrees can be used accordingly. The height of the protruding portion may usually be higher than the thickness of the first electrode.

The protrusion 11 is formed to surround the periphery of the pixel 17 so that light emitted from one pixel is guided to another pixel so that problems such as display blurring do not occur, but the present invention is not limited thereto. It can also be formed in pixels, and can form protrusions surrounding several pixels (FIG. 1B).

The first electrode 12 is formed on the protrusion 11, and ITO or the like of a transparent material may be used. The first electrode 12 may protrude along the protrusion shape of the protrusion 11 to prevent light from being guided along the first electrode 12.

The organic layer 13 is formed on the first electrode 12, and the organic layer 13 according to the present invention includes an organic light emitting layer, and may be formed of various organic materials such as a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer. It refers to at least one organic film made. Like the first electrode 12, the organic layer 13 also protrudes in conformity with the protruding shape of the protrusion 11.

The second electrode 14 is formed on the organic layer 13, the second electrode 14 in the present invention that is mainly applied to the back light emission may not be transparent, so aluminum, lithium, magnesium, aluminum-lithium, calcium, magnesium Materials such as indium, magnesium-silver and the like can be used. Since the second electrode 14 is not transparent, light does not guide and does not need to protrude along the shape of the protrusion 11, but in order to properly maintain the thickness of the second electrode 14, the shape of the second electrode 14 may be along the shape of the protrusion 11. Will protrude. Usually, the thickness of a 1st electrode is 100-10000 kPa, and the thickness of a 2nd electrode is 50-5000 kPa. When the thickness of the electrode is thin, there is a problem of high resistance, and when the thickness is thick, there is a problem that the material cost rises. In particular, when the thickness of the first electrode is increased, the transmittance decreases and thus the luminous efficiency is decreased. When the thickness of the second electrode is increased, the light emitting organic material deteriorates as a weak bonding material in the form of a polymer or a low molecule.

The protective layer 15 is formed on the second electrode 14 and may be formed to have a thickness sufficient to offset the shape of the protrusion 11 without canceling.

Meanwhile, FIG. 1C illustrates an active organic light emitting diode further including a transistor layer (TR layer) 16 between the substrate 10 and the first electrode 12, and as illustrated, the transistor layer 16 is further included. It will be appreciated by those skilled in the art that even if provided, the protrusion can be formed to increase the light efficiency.

Next, a second preferred embodiment of the present invention will be described in more detail with reference to FIG. 2A. 2A is a cross-sectional view of a bottom emission organic light emitting diode according to a second embodiment of the present invention. Accordingly, the organic light emitting diode includes a substrate 20, a first electrode 21, an organic layer 22, a second electrode 23, and a protective layer 24 on which recesses are formed.

The substrate 20 is an insulating substrate Transparent glass material may be used for the back light emission. The concave portion 26 is formed in a region other than the pixel 17 on the substrate 20. The concave inlet portion 26 may be scraped by a sharp blade or the like during the heat treatment process of the substrate 20, or may include a fine metal powder when manufacturing the substrate 20, and then irradiate a laser lamp to dissolve the metal powder. Can be used.

The formation of the concave portion 26 directly on the substrate 20 is because the light output can be increased by reflecting or refracting the light guided to the side surface of the substrate 20.

Concave inlet portion 26 is preferably formed in a shape that is pointed toward the inside of the substrate 20. When the angle is maintained at approximately 45 ° relative to the substrate surface, a constant luminance is obtained over a wide viewing angle range, and an angle of 20 to 60 ° may be used depending on the display device to be used. The height of the recess is 100 ~ 10000 ~. Below 100 mW, the factor of increasing the light output is insufficient, and above 100 mW, it may cause high cost and cracks on the substrate.

The concave portion 26 is formed around the periphery of the pixel as described in Embodiment 1 so that the light emitted from one pixel is guided to the other pixel so that problems such as display blurring do not occur. The present invention is not limited thereto, and may be formed even within one pixel, and may form concave portions surrounding several pixels.

The first electrode 21 is formed on the concave portion 26, ITO or the like of a transparent material may be used. The first electrode 21 may include a concave portion corresponding to the curved shape of the concave portion 26 to prevent light from being guided along the first electrode 21.

The organic layer 22 is formed on the first electrode 21, and the organic layer 22 in the present invention includes an organic light emitting layer, and may be formed of various organic materials such as a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer. It refers to at least one organic film made. Similar to the first electrode 21, the organic layer 22 also has a concave portion in conformity with the concave shape of the concave portion 26.

The second electrode 23 is formed on the organic layer 22, and in the present invention mainly applied to the back light emission, the second electrode 23 does not have to be transparent, so aluminum, lithium, magnesium, aluminum-lithium, calcium, magnesium Materials such as indium, magnesium-silver and the like can be used. Since the second electrode 23 is not transparent, light is not guided, and thus the second electrode 23 does not need to be provided with a concave portion according to the shape of the concave portion 26, but the concave portion 26 is appropriately maintained to maintain the thickness of the second electrode 23. Will protrude along the shape of The thickness of the first electrode and the second electrode is the same as that of the protruding portion, the thickness of the first electrode is usually 100 to 10000 mm 3, and the thickness of the second electrode is 50 to 5000 mm 3. When the thickness of the electrode is thin, there is a problem of high resistance, and when the thickness is thick, there is a problem that the material cost rises. In particular, when the thickness of the first electrode is increased, the transmittance decreases and thus the luminous efficiency is decreased. When the thickness of the second electrode is increased, the light emitting organic material deteriorates as a weak bonding material in the form of a polymer or a low molecule.

The protective layer 24 is formed on the second electrode 23 and may be formed to have a thickness sufficient to offset the shape of the recess 26.

Meanwhile, FIG. 2B illustrates an active organic light emitting diode further including a transistor layer 25 between the substrate 20 and the first electrode 21. Although the transistor layer 25 is further provided as shown in FIG. Those skilled in the art will appreciate that the concave concavity 25 can be formed to increase the light efficiency.

Hereinafter, a third preferred embodiment of the present invention will be described in detail with reference to FIG. 3A. 3A is a cross-sectional view of a bottom emission type organic light emitting diode according to a third embodiment of the present invention. Accordingly, the organic light emitting diode includes a substrate 30 having a recess, a filler 31 filled in the recess, a first electrode 32, an organic layer 33, a second electrode 34, and a protective layer 35. It includes.

The substrate 30 may be a transparent glass material or the like for back emission as an insulating substrate. Concave portions are formed in regions other than where pixels are to be formed on the substrate 30. The recess may be scraped by a sharp blade or the like during the heat treatment process of the substrate, or may include a method of dissolving metal powder by irradiating a laser lamp after incorporating fine metal powder or the like into the substrate. Forming the recess directly on the substrate is because the light output can be increased by reflecting or refracting the light guided to the side of the substrate 30.

It is preferable that the recess is formed on the substrate in a shape that is sharpened toward the inside of the substrate 30. When the angle is maintained at approximately 45 ° relative to the substrate surface, a constant luminance is obtained over a wide viewing angle range, and an angle of 20 to 60 ° may be used depending on the display device to be used. The height of the recess is 100 ~ 10000 ~. Below 100 mW, the factor of increasing the light output is insufficient, and above 100 mW, it may cause high cost and cracks on the substrate.

The recess is formed around the periphery of the pixel so that light emitted from one pixel is guided to another pixel so as not to cause a problem such as display blurring, but is not limited thereto. A recess may be formed to surround several pixels.

The filler 31 is filled with a material different from the substrate in the recessed part, and the refractive indexes of the substrate 30 and the recessed part are differently formed so that the light generated from the organic layer 33 is formed on the side surface of the substrate 30 as one waveguide layer. This is to allow more reflection or refraction to occur so that light is emitted to the outside of the substrate without being guided. As the material of the filler 31, for example, SiNx, Ta2O5, TiO2, MgF2, MgO, Al2O3, CaO, such as a transparent material different from the substrate may be used, but is not limited thereto.

The first electrode 32 is formed in a region on the substrate where the recess is not formed, thereby generating a height difference between the region where the first electrode 32 is formed and the region where the recess is formed, and a transparent material ITO or the like may be used.

The organic layer 33 is formed on the first electrode 32, and the organic layer 33 in the present invention includes an organic light emitting layer, and may be formed of various organic materials such as a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer. It refers to at least one organic film made. The organic layer 33 is formed on the substrate on which the first electrode 32 is formed, and the organic layer 33 is bent according to the region where the first electrode 32 is formed and the region where the recess is formed to have the recess portion. The recess portion has an effect of preventing light from being guided to the side as described above.

The second electrode 34 is formed on the organic layer 33, and in the present invention mainly applied to the back light emission, the second electrode 34 does not have to be transparent, so aluminum, lithium, magnesium, aluminum-lithium, calcium, magnesium Materials such as indium, magnesium-silver and the like can be used. At this time, the second electrode 34 also has a recessed portion according to the bending shape of the organic layer 33. Usually, the thickness of a 1st electrode is 100-10000 kPa, and the thickness of a 2nd electrode is 50-5000 kPa. When the thickness of the electrode is thin, there is a problem of high resistance, and when the thickness is thick, there is a problem that the material cost rises. In particular, when the thickness of the first electrode is increased, the transmittance decreases and thus the luminous efficiency is decreased. When the thickness of the second electrode is increased, the light emitting organic material deteriorates as a weak bonding material in the form of a polymer or a low molecule.

The protective layer 35 is formed on the second electrode 34, but may be formed to have a thickness sufficient to offset the shape of the recess portion.

Although the present invention has been described primarily with reference to the above embodiments, many other possible modifications and variations can be made without departing from the spirit and scope of the invention. For example, changes in the thickness or specificity of the respective layers, changes in the shape of the protrusions or recesses, etc. will be readily changeable by those skilled in the art.

The organic light emitting device according to the present invention has an effect of preventing the light emitted from the organic layer is guided to the side of each layer including the substrate to reduce the light efficiency.

The scope of the above-described invention is defined in the following claims, not bound by the description in the text of the specification, all modifications and variations belonging to the equivalent scope of the claims will fall within the scope of the invention.

Claims (23)

delete delete delete delete delete delete delete delete delete delete delete delete delete delete An organic light emitting device comprising a substrate, a first electrode formed on the substrate, an organic layer formed on the first electrode, and a second electrode formed on the organic layer. The recess is formed on the substrate, the recess is filled with a filler of a different material from the substrate, And the first electrode is formed in a region on the substrate where the recess is not formed, and the organic layer and the second electrode form a bent portion according to the bending of the first electrode. The method of claim 15, The filler is an organic light emitting device, characterized in that the refractive index is different from the substrate. The method of claim 15, The concave portion is formed in the periphery of each pixel of the organic layer. The method of claim 15, The height of the recess portion is an organic light emitting device, characterized in that formed in 100 ~ 10000Å. The method of claim 15, The wall surface of the recess is inclined so as to become sharp toward the inside of the substrate, the inclination angle of the organic light emitting device, characterized in that 20 to 60 ° based on the substrate surface. The method of claim 15, The filler is an organic light emitting device consisting of one selected from the group consisting of Ta2O5, TiO2, MgF2, MgO, Al2O3, CaO. The method of claim 15, The substrate is made of glass, the filler is an organic light emitting device, characterized in that the TiO2. Providing a substrate, forming a first electrode formed on the substrate, forming an organic layer formed on the first electrode, and forming a second electrode formed on the organic layer In the method of manufacturing an organic light emitting device, After providing the substrate, forming a recess on the provided substrate, and filling the recess with a filler of a different material from the substrate. The method of claim 22, In the substrate providing step is provided by mixing the metal powder on the substrate, In the forming of the concave portion, the method of manufacturing an organic light emitting device, characterized in that to form a concave portion by melting the metal powder by irradiating a laser.

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