KR100691310B1 - Organic Electro-Luminescence Display and Method of Manufacturing the same - Google Patents

Abstract

The present invention relates to the manufacture of high resolution organic EL displays using semiconductor single crystal substrates. That is, the present invention comprises a first electrode formed on a substrate, an organic EL layer, an organic EL light emitting element including a second electrode, and a protective layer encapsulating the organic EL light emitting element, wherein the substrate is The present invention relates to an organic EL display that is flexible and is a single crystal substrate that transmits light.

The present invention also includes an organic EL light emitting element including an organic EL layer and an electrode formed on a substrate, and a protective layer protecting the organic EL light emitting element, wherein the substrate is flexible and transmits a single crystal substrate. The present invention relates to an organic EL display characterized by being phosphorus.

In addition, the present invention relates to a method for manufacturing an organic EL display, comprising the steps of: preparing a single crystal substrate that is flexible and transmits light; forming an organic EL layer and an electrode on the single crystal substrate to provide an organic EL light emitting device; Forming a protective layer encapsulating the organic EL light emitting element.

In addition, the present invention relates to a method for manufacturing an organic EL display, comprising the steps of preparing an SOI substrate consisting of a base substrate, an insulating layer and a single crystal layer, and forming an organic EL layer and an electrode on the single crystal layer to provide an organic EL light emitting device. Forming a protective layer encapsulating the organic EL light emitting device, and removing the base substrate and the insulating layer of the SOI substrate to form the single crystal layer as a flexible and light transmitting single crystal substrate. Include.

Light Transmissive Monocrystalline Substrate, Nano SOI, Etching, Organic EL Display, Organic Light Emitting Layer, Flexible

Description

Organic EL display and method of manufacturing the same {Organic Electro-Luminescence Display and Method of Manufacturing the same}             

1 is a cross-sectional view of a conventional organic EL display

2 is a perspective view of a conventional organic EL display

3 is a cross-sectional view of an organic EL display according to the present invention.

4 is a cross-sectional view of another organic EL display according to the present invention.

5 is a manufacturing process diagram of a light transmitting single crystal substrate of the present invention.

Figure 6 is another manufacturing process diagram of the light transmitting single crystal substrate of the present invention

Figure 7 is a jig structure diagram of the present invention

8 is a photograph of a light transmitting single crystal substrate of the present invention.

Figure 9 is a photograph showing the bending characteristics of the light transmitting single crystal substrate of the present invention

<Description of Symbols for Major Parts of Drawings>

2: glass substrate

3: anode layer

4, 14: hole injection layer

5, 15: hole transport layer

6, 16: organic light emitting layer

7, 17: electron transport layer

8: cathode layer

9, 19: protective layer

12: light transmitting single crystal substrate

13: first electrode layer

18: second electrode layer

31: base substrate

32: insulation layer

33: single crystal layer

34: jig

35: KOH

36: HF

37: element layer

40: substrate

41: lower plate

42: top plate

45: heater

The present invention relates to a high resolution flexible organic EL (Electro-Luminescence) display using a flexible and transparent semiconductor single crystal substrate in the manufacture of a circuit driving element and a pixel element, and a method of manufacturing the same. That is, since the thinning technology of the single crystal silicon substrate is used, the active layer of the device is fabricated on the single crystal silicon substrate by applying a design rule of a general semiconductor process, thereby obtaining desired characteristics of the device and reducing the size of the device. A high-resolution flexible organic EL display is produced by imparting flexibility and light transmitting functions to a single crystal silicon substrate.

The organic EL display has various advantages, such as low power consumption and high-speed response, which can meet the needs of portability and moving image display, compared to the liquid crystal display which is the mainstream of flat panel display. It is attracting attention as a flat panel display that can replace.

1 and 2 are diagrams showing a schematic configuration of a general organic EL display 1. This organic electroluminescent display 1 is equipped with the transparent glass substrate 2, and the anode layer 3, Anode is formed by this transparent conductive material, such as ITO, on this glass substrate. On the anode layer 3, a hole injection layer 4 and a hole transport layer 5 for supplying holes by applying a voltage are formed, and on the anode layer 3, a small amount of organic dye is included as a dopant. An organic light emitting layer 6 is formed, and an electron injection layer 7 for supplying electrons by applying a voltage is formed thereon, and the cathode layer 8 of the conductive material, which is the uppermost layer, is formed thereon. ) Is formed. In addition, after the cathode layer is formed and the organic EL element is manufactured, the protective layer 9 which seals the organic EL element from the outside seals the organic EL element in order to protect the organic EL element which is very susceptible to oxidation.

In the organic EL display as described above, when a voltage is applied between the anode layer 3 and the cathode layer 8 by a power source, the hole injection layer 4 and the transfer layer stacked on the anode layer 3 to which the voltage is applied are transferred. Holes are injected from the transport layer 5 into the organic light emitting layer 6 and electrons are injected into the organic light emitting layer 6 from the electron injection layer 7 below the cathode layer 8 to which voltage is applied. In the organic light emitting layer 6 in which holes from the hole transport layer 5 and electrons from the electron injection layer 7 are respectively injected, holes and electrons recombine, and energy generated by the recombination is organic light emitting layer 6. It is absorbed by the organic dye contained in and emits light. Light generated from the organic light emitting layer 6 sequentially passes through the hole transport layer 5, the hole injection layer 4, the anode layer 3, and the glass substrate 2, and thus the back surface of the glass substrate 2 (bottom injection, Bottom injection). The organic EL display 1 may be manufactured by a method of emitting light in the upward direction of the organic EL display by manufacturing the above protective layer as a transparent material in addition to the structure of emitting light to the back surface of the substrate. It may be.

In addition to the driving method for passive matrix driving, the organic EL display may adopt a driving method for active matrix driving (which is advantageous for color displays) that is driven by using thin film transistors (TFTs) and the like.

The active matrix drive type organic EL display using the above TFT as a driving element is manufactured by forming TFTs on a glass substrate or a polycrystalline silicon layer, but such a TFT cannot use a conventional semiconductor process as it is, and therefore high density integration is impossible. In addition, there is a limitation in TFT device performance, so that a high performance TFT cannot be manufactured on a substrate, and it is difficult to integrate complex system circuits or reduce the size of the pixel device.

On the other hand, the technique of manufacturing an active matrix type organic EL display using the insulated gate field effect transistors formed on the single crystal semiconductor substrate is the same as that of the semiconductor process technology used in the field of large scale integrated circuits as compared to the case of using the organic substrate. It is advantageous in that it is applicable and can be formed by integrating high-performance transistors capable of driving low voltage at high speed on a substrate at high density. However, on the other hand, when manufacturing an organic EL element on a single crystal semiconductor substrate, the organic EL display has a problem of being limited to the top injection method because the substrate does not pass visible light.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to manufacture a flexible organic EL display using a single crystal substrate having flexibility and light transmission characteristics, as a semiconductor process to which fine design rules can be applied. And to provide a method for producing the same.

Another object of the present invention is to provide a top injection type organic EL display as well as a high performance bottom injection type organic EL display and its manufacturing method by using a single crystal substrate having flexible light transmitting characteristics.

Another object of the present invention is to provide a flexible organic EL display having excellent device characteristics and a method of manufacturing the same by using a silicon single crystal in the manufacture of a drive element such as a TFT.

It is still another object of the present invention to provide an organic EL display and a method for manufacturing the same, in which the substrate itself can function as an electrode by using a semiconductor single crystal substrate having flexible light transmitting characteristics, thereby simplifying the laminated structure.

Another additional object of the present invention is to provide a flexible organic EL display capable of providing a flexible system on display (SOD) by providing excellent device characteristics and reliability of single crystal silicon TFTs, thereby enabling integration of various circuit driving devices. To provide.

The organic EL display of the present invention for achieving the above object of the present invention surrounds the organic EL light emitting element comprising a first electrode formed on a substrate, an organic EL layer, a second electrode, and the organic EL light emitting element. Has a protective layer, and the substrate is a single crystal substrate that is flexible and transmits light. In this case, the first electrode includes a transparent electrode.

In addition, the organic EL display of the present invention includes an organic EL light emitting element including an organic EL layer and an electrode formed on a substrate, and a protective layer protecting the organic EL light emitting element, wherein the substrate is flexible and provides light. It is a single crystal substrate that transmits. In this case, the light transmitting single crystal substrate may have an electrode function.

In addition, the light transmissive single crystal substrate of the organic EL display of the present invention may be manufactured using an SOI manufacturing process, and the light transmissive single crystal substrate may have a thickness of several tens of nanometers to several micrometers.

In addition, the light transmitting single crystal substrate of the organic EL display of the present invention may include silicon or a compound semiconductor, and the silicon single crystal substrate may be a defectless single crystal and doped with impurities.

In addition, the organic EL layer of the organic EL display of the present invention includes an organic EL light emitting layer, or the organic EL layer includes a hole transport layer, an organic EL light emitting layer and an electron injection layer, or the organic EL layer is a hole injection layer, a hole A transport layer, an organic EL light emitting layer, and an electron injection layer can be included.

In addition, the organic EL display of the present invention may include a pixel portion and a driving element portion, and the driving element portion may include a thin film transistor.

In order to achieve the object of the present invention, a method of manufacturing an organic EL display of the present invention includes preparing a single crystal substrate that is flexible and transmits light, and forms an organic EL layer and an electrode on the single crystal substrate to form an organic EL light emitting device. And providing a protective layer surrounding the organic EL light emitting device. The preparing of the single crystal substrate may include preparing a single crystal substrate that is flexible and transmits light using an SOI substrate including a base substrate, an insulating layer, and a single crystal layer, and is flexible using the SOI substrate. Producing a single crystal substrate that transmits light includes removing the base substrate and the insulating layer of the SOI substrate to produce the single crystal layer as a flexible, light transmissive single crystal substrate.

In addition, the manufacturing method of the organic EL display of the present invention comprises the steps of preparing a SOI substrate consisting of a base substrate, an insulating layer and a single crystal layer, and providing an organic EL light emitting device by forming an organic EL layer and an electrode on the single crystal layer; And forming a protective layer encapsulating the organic EL light emitting element, and removing the base substrate and the insulating layer of the SOI substrate to produce the single crystal layer as a flexible and light transmitting single crystal substrate.

In the preparing of the organic EL light emitting device of the organic EL display manufacturing method of the present invention, an electrode may be formed between the single crystal layer and the substrate and the organic EL layer.

In addition, the step of removing the base substrate of the organic EL display manufacturing method of the present invention includes the step of removing the base substrate by wet etching with KOH, the step of removing the insulating layer by wet etching with HF to remove the insulating layer. It includes a step.

In addition, in the method of manufacturing the organic EL display of the present invention, the thickness of the flexible light transmitting single crystal substrate can be adjusted by adjusting the thickness of the single crystal layer of the SOI substrate.

In the manufacturing of the flexible light transmitting single crystal substrate of the organic EL display manufacturing method of the present invention, one surface of the SOI substrate may be etched using a jig.

In addition, the manufacturing method of the organic EL display of the present invention may further comprise the step of forming a drive element before the step of providing the organic EL light emitting element.

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

3 and 4 are cross-sectional views of the organic EL display according to the present invention. In the organic EL display 11 of the present invention, a first electrode layer 13 is formed on a silicon single crystal substrate 12 having flexibility and light transmitting characteristics, and on the first electrode layer 13, an organic EL layer ( 14 to 17 are formed, and the second electrode layer 18 of the conductive material serving as the uppermost layer is formed thereon. In addition, after the organic EL element is manufactured by forming the second electrode layer 18, a protective layer 19 for enclosing the organic EL element from the outside surrounds the organic EL element in order to protect the organic EL element which is very susceptible to oxidation.

The silicon single crystal substrate 12 is manufactured by thinning a silicon on insulator (SOI) substrate on which an insulating layer is formed on a base substrate and a high quality silicon single crystal layer is formed thereon. Substrate thinning will be described later in detail. By using a defect-free high quality silicon single crystal substrate as a substrate of an organic EL display, a high performance device can be manufactured by applying a general semiconductor manufacturing technique used for semiconductor integrated circuits. In addition, since the silicon single crystal substrate can be manufactured to a sufficiently thin thickness, for example, 5 μm or less, the silicon single crystal substrate has a flexible property of transmitting light and bending the substrate. As a result, the silicon single crystal substrate transmits light while using a high quality silicon single crystal substrate as an organic EL substrate, so that the emitted light can be emitted in the direction of the substrate, thereby producing a flat and bendable flexible display. Here, the silicon single crystal substrate preferably has a transmittance of 50% or more with respect to visible light. In addition, since the silicon single crystal substrate 12 can function as an electrode together with the substrate function by adjusting the resistance value (about 15 Ω / □ or less) by doping impurities, as shown in FIG. 4, the silicon single crystal does not form the first electrode layer. The organic EL display 21 may be manufactured by forming an organic EL layer directly on the substrate 12.

The first electrode layer 13 may be either an anode or a cathode. In the case where the first electrode layer is used as the anode, a material having a large work function is used to efficiently inject holes. In the bottom injection type organic EL device, since light is emitted through the anode, the anode is required to be transparent, and a conductive metal oxide such as ITO and IZO is mainly used. In the present invention, an anode is formed using a transparent conductive metal oxide such as ITO or IZO. In the case where the first electrode 13 is used as a cathode, an electron injectable metal made of alkali metals such as lithium and sodium, which are materials having a small work function, alkaline earth metals such as potassium, calcium, magnesium and strontium, or fluorides thereof; Alloys and compounds with other metals are used. Further, the first electrode layer may not be formed in the organic EL display of the present invention as described above (see Fig. 4). The ITO film, which is mainly used as the first electrode layer, has a resistance of 10 to 15 Ω / □ and a work function of 4.8 eV, but the surface roughness (about 50 to 70 GPa) is bad and adversely affects the hole injection, thereby making a buffer layer (eg a hole injection layer) To compensate. However, since the silicon single crystal substrate of the present invention exhibits an appropriate resistance value by impurity doping and has a work function of 4.05 eV or more and the surface roughness is adjusted to about 5 GPa or less, it does not require a hole injection layer with the function of the substrate. Function as an excellent first electrode.

When the organic EL display of the present invention performs active matrix driving, the first electrode layer 13 is formed in a separate form corresponding to each of the TFTs as the driving elements, and is connected to the source electrodes or the drain electrodes of the TFTs. In other words, when connected to the source electrode, it functions as an anode, and when connected to the drain electrode, it functions as a cathode. Alternatively, when the organic EL display of the present invention performs passive matrix driving, a first electrode having a line pattern shape is formed on a silicon single crystal substrate without forming a TFT.

The organic EL layers 14 to 17 are layers that emit light substantially, and include at least an organic EL light emitting layer 16. The hole injection layer 14 and the hole transport layer supplying holes by applying a voltage as necessary. (15) and / or a voltage interposed between the electron injection layer 17 and the like for supplying electrons. Specifically, what consists of the following laminated constitution is selectively employ | adopted.

(1) organic EL light emitting layer

(2) hole injection layer / organic EL light emitting layer

(3) organic EL light emitting layer / electron injection layer

(4) hole injection layer / organic EL light emitting layer / electron injection layer

(5) hole transport layer / organic EL light emitting layer / electron injection layer

(6) hole injection layer / hole transport layer / organic EL light emitting layer / electron injection layer

(7) hole injection layer / hole transport layer / organic EL light emitting layer / electron transport layer / electron injection layer

In the above, the anode is connected to the organic EL light emitting layer or the hole injection layer, the cathode is connected to the organic EL light emitting layer or the electron injection layer, and known materials are used as the material of each layer. For example, CuPc (Copper Phthalocyanine) may be used as the hole injection layer, and NPB (N, N'-bis- (1-naphthyl) -N, N'-diphenyl-1,1'- may be used as the hole transport layer. biphenyl-4,4'-diamine) may be used, and doped Alq3 (tris- (8-hydroxyquinolinato) aluminum (III)) may be used as the organic EL light emitting layer, and Alq3 (tris-) may be used as the electron transport layer. (8-hydroxyquinolinato) aluminum (III)) may be used, and LiF (lithium fluoride) may be used as the electron injection layer.

The second electrode 18 is a layer for efficiently injecting electrons or holes into the organic EL layers 14 to 17. In the case of the top injection type organic EL display, it is required to be transparent in the emission wavelength region. When the second electrode 18 is used as a cathode, the material is required to have a small work function for efficiently injecting electrons. When the second electrode 18 is used as an anode, a work function is used to increase hole injection efficiency. Larger materials are used.

The protective layer 19 is provided so as to surround these layers in order to protect the second electrode and the following layers formed as described above. The protective layer 19 prevents the permeation of oxygen, low molecular weight components, moisture, and the like from the external environment, thereby preventing the function of the organic EL layers 14 to 17 from being lowered by them. Therefore, the protective layer 19 is electrically insulating, has a barrier property against moisture, oxygen, and the like, and preferably has a hardness of an appropriate level or more. In addition, the protective layer 19 may be formed of a single layer or a plurality of layers.

Hereinafter, the manufacturing method of the organic electroluminescent display of this invention is demonstrated. The light transmitting single crystal substrate of the present invention forms an insulating layer 32 on the base substrate 31 and thins a silicon on insulator (SOI) substrate on which a high quality silicon single crystal layer 33 is formed thereon. Manufacture. Regarding the manufacture of the SOI substrate, reference may be made to Korean Patent Application No. 2002-47351, which is an applicant patent of the present invention. For thinning the substrate, Korean Patent Application No. 2003-0027825, which is an application patent of the present invention participant, may be referred to. It is described in detail in the issue. Here, the method of manufacturing the light transmitting semiconductor single crystal substrate used as the substrate of the organic EL display of the present invention will be described in more detail below with reference to FIGS. 5 and 6.

First, the jig used in the present invention will be described. As shown in FIG. 7, the jig consists of an upper plate 42 and a lower plate 41 so that the substrate 40 is installed between the upper plate and the lower plate. Each such plate is made of a chemically stable material such as Teflon. The upper plate is provided with a chemical bath 43 at the upper portion where the upper plate and the lower plate are combined to contain a chemical solution. These chemical containers are manufactured in a penetrating type, and are manufactured in various forms as necessary, such as a rectangular cylinder and a cylinder. In addition, the upper plate and the lower plate is provided with fixing means (44, 47) for fixing the two plates when the two plates are bonded.

By using such a jig, only one side of the substrate may be wet-etched. That is, the surface of the substrate 40 to be etched is installed on the lower plate 41 so that the upper plate 42 faces the upper plate 42, and the upper plate and the lower plate are joined and fixed, and then the etching solution is supplied to the chemical container 43 to expose them. One side of the prepared wafer is etched. At this time, the heater 45 and the thermometer 46 coated with Teflon are installed in the chemical container according to the etching conditions and the etching temperature is controlled.

A process of etching one entire surface of the substrate using a jig will be described in more detail below with reference to FIG. 8.

An SOI wafer formed of a base substrate 31, an insulating layer 32 formed thereon, and a silicon single crystal layer 33 formed on the insulating layer is prepared with the surface to be etched up as shown in FIG. At this time, the silicon unity may be formed or the element layer may not be formed. The prepared substrate is fixed by holding the wafer edge using the jig 34 described above to expose the entire back side of the base substrate (the surface without the single crystal layer 31) (Fig. 5B).

As described above, the base substrate is etched by supplying the KOH solution 35 to the rear surface of the fixed and exposed base substrate (c in FIG. 5), and after discharging the KOH solution, the HF solution 36 is supplied to the insulating layer 32. ) Is etched (d in FIG. 5) to produce a pure thin silicon single crystal film 33b (FIG. 5 e). At this time, the insulating layer 32 serves as an etch stop layer (stopper) for the etching of the base substrate by the KOH solution, and the removal of the insulating layer 32 by the HF solution may be performed while the jig is fixed, or a single crystal When the element layer is not formed in the layer 33, the jig may be loosened and the whole to-be-processed object may be soaked in HF solution. Since the thin silicon single crystal substrate 33b manufactured as described above is thin, it has light transmitting characteristics and flexibility. The thickness of the defect-free silicon single crystal substrate is controlled in the manufacturing process of the nano SOI single crystal substrate. That is, if the single crystal layer 33 is formed sufficiently thin (for example, 5 micrometers or less) when manufacturing a nano SOI substrate, the thickness of the light transmissive single crystal substrate 33b after thinning will also become thin enough. In this case, the thickness of the light transmitting single crystal substrate 33b may be reduced from several micrometers to several tens of nanometers or less.

A process of etching a portion of one side of the substrate using a jig will be described in more detail below with reference to FIG. 6.

As shown in FIG. 6A, an SOI substrate formed of a base substrate 31, an insulating layer 32 formed thereon, and a silicon single crystal layer 33 formed on the insulating layer is prepared. At this time, a desired element 37 (for example, an organic EL display) may be formed on the silicon single crystal layer 33 as necessary, or the element may not be formed. Using the jig 34 described above, the prepared substrate is fixed by pressing the upper portion of the substrate around the substrate so that a part of the rear surface of the substrate is exposed (Fig. 6B).

As described above, the base substrate 31 is etched by supplying a KOH solution to the rear surface of the fixed and exposed substrate (FIG. 6c), and after discharging the KOH solution, the HF solution is supplied to etch the insulating layer 32. In other words, the base substrate 32 is etched by the KOH solution, and the insulating layer 32 serves as an etch stop layer. Thereafter, after discharging the KOH solution, when the HF solution is supplied, the insulating layer 32 is etched by HF.

The thin silicon single crystal substrate thus manufactured has a light transmission characteristic and flexibility because of its thin thickness. In addition, as described above, the thickness of the light transmitting silicon single crystal substrate is controlled in the manufacturing process of the nano SOI single crystal substrate.

The object to be etched as described above leaves the peripheral portion unetched (Fig. 6E), which serves as a handler to facilitate substrate handling when processing the substrate in a subsequent process. In this case, if necessary, the periphery may be cut to prepare a light transmitting flexible silicon single crystal film.

The method of etching only one surface of the substrate using the jig can easily manufacture a light transmitting flexible single crystal substrate through a simple process. That is, since the back surface of the base substrate is etched using a jig without any additional process, the process step is reduced. In addition, the shape of the chemical container of the upper plate can be changed to produce a light transmitting flexible substrate having a desired shape. In other words, when the circular substrate is caught and etched using a jig having a rectangular cylindrical chemical container, a rectangular light transmitting flexible single crystal substrate can be obtained.

In addition, in the above description, a method of etching one side of the substrate by using a jig has been described, but before fixing the substrate by using the jig, the surface to be etched is ground to a predetermined thickness in advance, and then the The exposed surface can also be etched. In this case, the etching time of the exposed surface of the substrate can be significantly reduced.

An organic EL display is manufactured by sequentially forming an anode layer, an organic EL layer, and a cathode layer on a light-transmitting flexible single crystal substrate manufactured as described above, and then forming a protective layer protecting each layer (see FIGS. 3 and 4). ). In this case, as described above, the anode layer, the organic EL layer, and the cathode layer are sequentially formed on the single crystal layer 31 of the SOI substrate, and then a protective layer for protecting the respective layers is formed. The organic EL display may be manufactured by etching. In addition, depending on the laminated structure of the organic EL display, the organic EL layer may be formed directly without forming the anode layer if necessary. The organic EL layers such as the hole injection layer, the hole transport layer, the organic EL light emitting layer, and the electron injection layer are preferably manufactured in a vacuum atmosphere or an inert gas atmosphere such as nitrogen argon. In addition, after the formation of the organic EL layer, the cathode layer and the protective layer in direct contact with each of the layers are also preferably processed in an inert gas atmosphere such as vacuum atmosphere or nitrogen argon to protect the organic EL layer.

In the above organic EL display manufacturing method, a driving element portion (for example, TFT) may be formed in advance on the light transmitting polycrystalline substrate according to the organic EL display driving method.

<Example>

(Production of a light transmitting flexible single crystal substrate)

A 4 inch SOI substrate formed of a base substrate 31, an insulating layer 32 having a thickness of about 1500 GPa formed thereon, and a silicon single crystal layer 33 having a thickness of about 5 µm formed on the insulating layer is prepared. In this case, the silicon single crystal layer is doped with impurities such as boron and phosphorus to have a resistance value of about 15 Ω / □ or less, and the surface roughness of the single crystal layer is 5 GPa or less. The SOI substrate prepared as described above is fixed by pressing the peripheral portion of the substrate with the upper plate so that a part of the substrate rear surface (base substrate) is exposed using a jig. The base substrate 31 is etched by supplying a 30% KOH solution (0.7 μm / min) maintained at 80 ° C. on the rear surface of the fixed and exposed substrate as described above, and after discharging the KOH solution, 49% HF solution is The insulating layer 32 is etched and removed to prepare a light transmitting silicon single crystal substrate having a thickness of about 5 μm. Since the light-transmitting silicon single crystal substrate manufactured as described above transmits light as shown in FIG. 8, the newspaper 82 located under the silicon single crystal substrate 81 can be clearly read. In addition, when the periphery (handler) of the light-transmissive silicon substrate manufactured as described above is removed, as shown in FIG. 9, the light-transmissive silicon substrate 91 can be bent at a predetermined curvature, thereby providing very flexible and transparent flexibility. It is made into a film.

(Manufacture of Organic EL Display)

An anode layer is formed by coating an ITO transparent electrode on the light-transmitting flexible silicon single crystal substrate prepared as described above. In this case, the ITO electrode has a thickness of about 110 nm, a resistance of 10 to 15 Ω / □ and a work function of about 4.8 eV. Spin NPB (N, N'-bis- (1-naphthyl) -N, N'-diphenyl-1, 1'-biphenyl-4, 4'-diamine) having a thickness of about 1500 mm on the ITO electrode prepared as described above. Coating with a coating or inkjet printing technique forms a hole transport layer. On the hole transport layer, Alq ³ (tris- (8-hydroxyquinolinato) aluminum (III)) having a thickness of about 600 mm ^{3 is} coated by spin coating or inkjet printing to form an organic EL light emitting layer and / or an electron transporting layer. On the organic light emitting layer, LiF (lithium fluoride) having a thickness of about 7 μs is coated by spin coating or inkjet printing to form an electron injection layer. An organic EL element is completed by forming a cathode layer of Al (aluminum) having a thickness of about 300 mW on the electron injection layer. When voltage is applied to the anode layer and the cathode layer of the organic EL device manufactured as described above, the organic EL device emits light.

At this time, as described above, first, the anode layer, the organic EL layer, and the cathode layer are sequentially formed on the single crystal layer 31 of the SOI substrate, and then a protective layer is formed to protect each layer. The organic EL display may be manufactured by etching the rear surface in the same manner as described above.

Although the present invention has been described in detail above, the present invention is not limited thereto and may be modified or improved by those skilled in the art within the technical spirit of the present invention.

The organic EL display of the present invention having the above-described configuration is manufactured using a single crystal substrate having flexibility and light transmission characteristics, so that the entire display can be bent due to its high resolution and flexibility.                     

The organic EL display of the present invention having the above-described configuration uses a single crystal substrate having flexibility and light transmission characteristics, so that a semiconductor process to which a fine design rule can be applied can be applied as it is.

The present invention can manufacture not only a top injection organic EL display but also a high performance bottom injection organic EL display by using a single crystal substrate having flexible light transmitting characteristics.

In addition, the present invention makes it possible to manufacture a driving circuit having excellent device characteristics such as a high performance TFT together with the pixel portion by using a single crystal substrate having flexible light transmitting characteristics.

In addition, the present invention can produce a high performance organic EL display in which the substrate itself can function as an electrode by using a single crystal substrate having flexible light transmitting characteristics, thereby simplifying the laminated structure.

In addition, the present invention uses a single crystal substrate having a flexible light transmission characteristics, the excellent device characteristics and reliability of the single crystal silicon TFT enables the integration of various circuit driving devices to manufacture a flexible system on display (SOD). .

In addition, the present invention can produce a flexible light-transmitting single crystal substrate for an organic EL display whose thickness can be adjusted through a relatively simple and easy manufacturing process.

Claims (26)

An organic EL light emitting element comprising a first electrode formed on a substrate, an organic EL layer, and a second electrode; An organic EL display comprising a protective layer surrounding the organic EL light emitting element, The substrate is a single crystal substrate that is flexible and transmits light, and has an organic EL display having a thickness of not more than 5 micrometers and several tens of nanometers. An organic EL display according to claim 1, wherein the first electrode comprises a transparent electrode. An organic EL light emitting element comprising an organic EL layer and an electrode formed on a substrate, As an organic electroluminescent display containing the protective layer which protects said organic electroluminescent element, The substrate is a single crystal substrate that is flexible and transmits light, and has an organic EL display having a thickness of not more than 5 micrometers and several tens of nanometers. The organic EL display according to claim 3, wherein the light transmitting single crystal substrate has an electrode function. The organic EL display according to any one of claims 1 to 4, wherein the light transmitting single crystal substrate is manufactured using an SOI manufacturing process. delete The organic EL display according to any one of claims 1 to 4, wherein the light transmissive single crystal substrate comprises silicon or a compound semiconductor. 8. An organic EL display according to claim 7, wherein the silicon single crystal substrate is a defectless single crystal and is doped with impurities. The organic EL display according to any one of claims 1 to 4, wherein the organic EL layer includes an organic EL light emitting layer. The organic EL display according to any one of claims 1 to 4, wherein the organic EL layer includes a hole transport layer, an organic EL light emitting layer, and an electron injection layer. The organic EL display according to any one of claims 1 to 4, wherein the organic EL layer includes a hole injection layer, a hole transport layer, an organic EL light emitting layer, and an electron injection layer. The organic EL display according to any one of claims 1 to 4, wherein the organic EL layer includes a hole injection layer, a hole transport layer, an organic EL light emitting layer, an electron transport layer, and an electron injection layer. The organic EL display according to any one of claims 1 to 4, wherein the organic EL display includes a pixel portion and a driving element portion. The organic EL display according to claim 13, wherein the driving element portion comprises a thin film transistor. Removing the base substrate and the insulating layer of the SOI substrate consisting of a base substrate, an insulating layer, and a single crystal layer to produce a flexible, light transmitting single crystal substrate; Forming an organic EL layer and an electrode on the single crystal substrate to provide an organic LE light emitting device; Forming a protective layer surrounding the organic EL light emitting element; delete The method of claim 15, wherein the manufacturing of the flexible and light-transmitting single crystal substrate using the SOI substrate comprises removing the base substrate and the insulating layer of the SOI substrate to make the single crystal layer flexible and light transmitting. Method for manufacturing an organic EL display comprising the step of manufacturing with Preparing an SOI substrate comprising a base substrate, an insulating layer, and a single crystal layer; Forming an organic EL layer and an electrode on the single crystal layer to provide an organic EL light emitting device; Forming a protective layer surrounding the organic EL light emitting element; Removing the base substrate and the insulating layer of the SOI substrate to produce a flexible, light-transmitting single crystal substrate. 19. The organic EL display according to any one of claims 15, 17 and 18, wherein the step of providing the organic EL light emitting element forms an electrode between the single crystal layer and the substrate and the organic EL layer. Manufacturing method 19. The manufacturing method of an organic EL display according to claim 17 or 18, wherein the removing of the base substrate and the insulating layer comprises removing the base substrate and the insulating layer by wet etching. 21. The method of claim 20, wherein removing the base substrate and the insulating layer comprises grinding the base substrate to a predetermined thickness before wet etching the base substrate and the insulating layer. 21. The method of claim 20, wherein removing the base substrate comprises removing the base substrate by wet etching with KOH. 21. The method of claim 20, wherein removing the insulating layer comprises removing the insulating layer by wet etching with HF. 19. The method of manufacturing an organic EL display according to any one of claims 15, 17 and 18, wherein the thickness of the flexible light transmitting single crystal substrate is adjusted by adjusting the thickness of the single crystal layer of the SOI substrate. 19. The manufacturing of the organic EL display according to any one of claims 15, 17 and 18, wherein the manufacturing of the flexible light transmitting single crystal substrate is performed by etching one surface of the SOI substrate using a jig. Way 19. The manufacturing method of an organic EL display according to any one of claims 15, 17 and 18, further comprising the step of forming a driving element before the step of providing the organic EL light emitting element.

Images