KR100870542B1 - Organic light-emitting device with an organic-inorganic hybrid hole-injection/transporting layer and manufacturing method of the same - Google Patents

Abstract

The present invention has a surface area of 1000 Fabrication of an organic electroluminescent device in which a hole injection-transport material is directly dispersed in a silica mesoporous molecular sieve pore having a pore size of more than ㎡ / g and having a nanometer arrangement and using this as a single hole injection-transport layer And the performance of the device, the surface area is 1000 It is possible to disperse the hole injection-transport material in the silica mesoporous molecular sieve pores having m2 / g or more and having a nanometer size and regular arrangement thereof. The use of silica mesoporous molecular sieves with very high surface area, nanometer size and regularly arranged pores makes it possible to disperse the organics responsible for hole injection-transport, and the hole injection-transport organics to the inorganic walls. It is possible to improve thermal and mechanical stability, and by using a well-known and relatively inexpensive material among the existing hole injection-transport organic materials, it is possible to improve the performance of the existing organic electroluminescent device and reduce the manufacturing cost of the device. .

Organic-inorganic, hybrid, hole, injection-transport, mesoporous, molecular sieve, organic electroluminescent device, TPD

Description

Organic light-emitting device with an organic-inorganic hybrid hole-injection / transporting layer and manufacturing method of the same}

Figure 1 is a schematic diagram of the synthesis process of the silica mesoporous molecular sieve film constituting the organic-inorganic hybrid organic electroluminescent device of the present invention.

Figure 2 is a cross-linking process of the hydrolysis and dehydration of tetraethoxysilane as an example of the pore wall forming material in the synthesis process of the silica mesoporous molecular sieve film constituting the organic-inorganic hybrid organic electroluminescent device of the present invention Reaction mechanism.

3 is a schematic diagram of various pore structures of a silica mesoporous molecular sieve film.

Figure 4 is a schematic diagram for the production of the organic-inorganic hybrid organic electroluminescent device of the present invention.

Figure 5 is a flow chart illustrating a process for preparing a silica mesoporous molecular sieve film solution having a regular hexagonal pore arrangement in accordance with an embodiment of the present invention.

FIG. 6 is a flow chart illustrating a silica film synthesis process in which pore arrays of regular hexagonal structures are formed with mesopores on an indium-tin oxide (ITO) -coated glass sheet according to an embodiment of the present invention.

7 is a flow chart illustrating the incorporation process of TPD into the pores of a mesoporous silica film (MS) coated on an indium-tin oxide (ITO) glass plate according to an embodiment of the present invention.

8 is a flowchart illustrating a manufacturing process of an organic electroluminescent device having an organic-inorganic hybrid hole transport layer according to an exemplary embodiment of the present invention.

FIG. 9 is a scanning electron micrograph of a sample in which a mesoporous silica film (MS) was formed on an indium-tin oxide (ITO) coated glass plate. FIG.

10 is an x-ray diffraction pattern of a mesoporous silica film (MS) sample.

Fig. 11 is a transmission electron micrograph of (a) (100) and (b) (110) planes for a mesoporous silica film (MS) sample.

12 is an atomic beam micrograph of the surface of a mesoporous silica film (MS) sample.

Figure 13 is a nitrogen adsorption / desorption isotherm of the mesoporous silica film (MS) sample. Inset graph shows pore size distribution.

FIG. 14 is x-ray photoelectron spectroscopy data for a sample of mesoporous silica film (TIMS) in which TPD is incorporated into pores on a glass plate coated with an indium-tin oxide (ITO) of the present invention. FIG.

FIG. 15 is an organic-inorganic hybrid organic electroluminescent device in which all of the mesoporous silica, the electron injection-transport material (Alq3), and Al, which are TPDs, are incorporated into pores on a glass plate coated with indium-tin oxide (ITO). Data of instantaneous photocurrent measured by time-of-flight analysis.

FIG. 16 shows the voltage-current for an organic electroluminescent device comprising a sample in which a TPD is incorporated into a pore into a hole injection-transport layer and a sample directly coated with TPD (FIG. 16A). ) And voltage-luminescence (FIG. 16 (B)) measurement data; (a) ITO / TIMS (110 nm) / Alq3 (50 nm) / Al, (b) ITO / TIMS (110 nm) / Alq3 (70 nm) / Al, (c) ITO / TIMS (110 nm) / Alq3 (110 nm) / Al, (d) ITO / TPD (110 nm) / Alq3 (70 nm) / Al, (e) ITO / TPD (110 nm) / Alq3 (110 nm) / Al, (f) ITO / TPD (50 nm) / Alq 3 (50 nm) / Al. The graph inserted in FIG. 16 (A) shows ITO / TIMS (110 nm) / Alq3 (70 nm) (TIMS), ITO / MS (110 nm) / TPD (50 nm) / Alq3 (MS / TPD), ITO / An organic electroluminescent device composed of TPD (50 nm) / Alq 3 (70 nm) (MS).

FIG. 17 is current density-current efficiency measurement data for organic electroluminescent devices, and the configuration of each device is as follows: (a) ITO / TIMS (110 nm) / Alq 3 (50 nm) / Al, (b) ITO / TIMS (110 nm) / Alq3 (70 nm) / Al, (c) ITO / TIMS (110 nm) / Alq3 (110 nm) / Al, (d) ITO / TPD (110 nm) / Alq3 (70 nm ) / Al, (e) ITO / TPD (110 nm) / Alq3 (110 nm) / Al, (f) ITO / TPD (50 nm) / Alq3 (50 nm) / Al

18 is a CIE color coordinate system.

The present invention provides an organic material by using, as a hole injection-transport layer, a mesoporous molecular sieve in which the hole injection-transport material is directly dispersed in a silica mesoporous molecular sieve pore having a large surface area and a nanometer size and having a regular structure thereof. The present invention relates to an organic electroluminescent device and a method of manufacturing the same, which can enhance the high dispersion and thermal and mechanical stability.

Organic EL is spotlighted as an ideal display device that is solid and self-luminous. The organic EL can drive at a low voltage below 15V, can design ultra-thin products, has the advantage of fast response speed, excellent brightness, and realization of all colors in the visible region. Currently, it is applied to sub-displays of mobile phones, automobiles, industrial applications, and consumer devices, but organic EL has high expectations for applications other than simple character display.

One problem with organic ELs is their lifetime. Most organic molecules are weak to oxygen or moisture. In addition, organic molecules are more likely to deteriorate by reacting with oxygen or moisture when in an excited state than in the ground state. And how well these organic molecules are dispersed also determines the performance of the organic EL device. Therefore, in order to increase the thermal, mechanical stability, and dispersion of these organics, other researchers have attempted to prepare complexes with inorganic materials.

Wu et al . Describe poly [2-methoxy-5 (2'-ethyl-hexyloxy) -1,4 used as a hole injection-transport material in pores of silica mesoporous materials having a hexagonal pore arrangement. -Phenylene vinylene] (MEH-PPV) polymers were incorporated (JA Wu, AF Gross, SH Tlbert, J. Phys. Chem., 1999, 103, 2374-2384). And Molenkamp et al. A poly [2-methoxy-5 (2'-ethyl-hexyloxy) -1,4-phenylene vinylene] (MEH-PPV) polymer is incorporated into the pores of the mesoporous silica film so that these polymer chains are high dipoles. It was reported to have an array (WC Molenkamp, M. Watanabe, H. Miyata, SH Tolbert, J. Am. Chem. Soc., 2004, 126, 4476-4477.).

However, they did not apply this organic and mesoporous composite to organic electroluminescent devices (OLEDs). The hole injection-transport material, MEH-PPV, is a rather expensive material. Improving the performance of the organic EL device is also important, but reducing such a device manufacturing cost is an important part that can reduce the cost of the product using the organic EL device.
In addition, US Pat. No. 6,592,764 et al. Has reported an example of preparing an intermediate porous material using a block copolymer, but has not been directly applied to an organic electroluminescent device using this material. On the other hand, Japanese Patent Laid-Open No. 8-279623, US Patent Publication No. 2006-071233, Japanese Patent Publication No. 2003-302686, Korean Patent Publication No. 2005-023572, Korean Patent Publication No. 2000-073117, and the like, The invention has been reported to be applied to an organic electroluminescent device having a two-layer structure by inserting a porous material or a mesoporous material between a general hole injection-transport layer and an ITO coated glass, but as in the present invention, the material of the hole injection-transport layer Is directly incorporated into the mesoporous material, and there is no example applied to the organic electroluminescent device using this as a hole injection-transport layer.

An object of the present invention is to provide an organic-inorganic hybrid organic electroluminescent device capable of increasing the thermal and mechanical stability of organic molecules acting as a hole injection-transport layer.

Another object of the present invention is to provide an organic electroluminescent device having a low driving voltage of the device by using an organic-inorganic hybrid hole injection-transport layer.

In addition, another object of the present invention is to increase the degree of dispersion of organic molecules acting as a hole injection-transport layer by using an inorganic mesoporous molecular sieve having a very high surface area and having pores arranged regularly at a nanometer size. It is to provide a light emitting device.

In addition, another object of the present invention is to present the organic molecules acting as the hole injection-transport layer with high dispersibility in the pores of the inorganic mesoporous molecular sieve film having a very high surface area. The present invention provides a method of manufacturing an organic electroluminescent device which increases the economic efficiency of device manufacturing by making a hole injection-transporting organic molecular layer and having similar performance to that of a conventional one.

It is another object of the present invention to provide a method for manufacturing an organic electroluminescent device having improved economic efficiency in manufacturing an organic electroluminescent device by using an inexpensive organic molecule serving as a hole injection-transport layer.

In addition, another object of the present invention is organic electroluminescence capable of mass production through the improvement of the production process by using a solution supporting method under the atmospheric pressure of room temperature, rather than high vacuum thermal evaporation method in the production of organic molecular layer acting as a hole injection-transport layer It is to provide a method for manufacturing a device.

Other objects, features and advantages of the present invention will become apparent from the following description.

The technical problem as described above has a surface area of 1000 Organic electroluminescence using an organic-inorganic hybrid hole injection-transport layer by forming a hole injection-transport material in the pores of an inorganic mesoporous molecular sieve film having a size of 2 m / g or more and having a nanometer size and a regular arrangement thereof It can be achieved by manufacturing the device.

Preferably, the inorganic mesoporous molecular sieve film may be a material in which the skeleton of the pores is in the form of an oxide and has a hydroxyl group on the pore surface.

Preferably, the inorganic mesoporous molecular sieve film may be obtained by using an inorganic source selected from a silica source, an organic hybrid silica source, and a titanium oxide source as a pore wall forming material.

Preferably, the inorganic mesoporous molecular sieve film may have a hexagonal structure, a cube structure, or a disordered structure in the arrangement of the pores.

Preferably, the surfactant (CH ₃ (CH ₂ ) ₁₁ N (CH ₃ ) ₃ Br, CH ₃ (CH ₂ ) ₁₅ N (template) as a template for synthesizing inorganic mesoporous molecular sieve film having various pores of various structures CH ₃ ) ₃ Br, CH ₃ (CH ₂ ) ₁₇ N (CH ₃ ) ₃ Br) or block copolymer (poly (ethylene oxide) poly (propyleneoxide) -poly (ethylene oxide) oxide) - block -poly (propylene oxide ) - block -poly (ethylene oxide), hereinafter PEO-PPO-PEO block copolymers) and the double-copolymer ((poly (etylene oxide-poly (ethylethylene), PEO-PEE)) It may be selected from.

Preferably, the inorganic mesoporous molecular sieve film may have various sizes of pores.

Preferably, the surfactant (CH ₃ (CH ₂ ) ₁₁ N (CH ₃ ) ₃ Br, CH ₃ (CH ₂ ) ₁₅ N as a template for the synthesis of inorganic mesoporous molecular sieve film having a mesopore of various pore size (CH ₃ ) ₃ Br, CH ₃ (CH ₂ ) ₁₇ N (CH ₃ ) ₃ Br) or block copolymer (poly (ethylene oxide) poly (propyleneoxide) -poly (ethylene oxide) ethylene oxide) - block -poly (propylene oxide) - block -poly (ethylene oxide), hereinafter PEO-PPO-PEO block copolymers) and the double-copolymer ((poly (etylene oxide-poly (ethylethylene), PEO-PEE) ) May be selected from.

Preferably, the hole injection-transport layer material may be selected from TPD, MEH-PPV, CuPc, PEDT / PSS, TDAB, PVK, and PF.

Preferably, the electron injection-transporting layer material may be selected from Alq3, PBD, TPBI, BCP.

Preferably, the anode material may be selected from Al, Ag-Mg, Al-Ca, Al-Li, AlLiF.

Preferably, a volume of mesoporous silica film pores with a solution of 3 wt% hole injection-transport material using a solution loading method for incorporating the hole injection-transport material into the mesoporous silica film pores as the hole injection-transport layer (3 x 10 ¹⁴ nm 3) may carry 3 × 10 ¹⁴ hole injection-transport material molecules.

In addition, the technical problem of the present invention can be achieved by measuring the hole mobility, voltage-current, voltage-luminescence, current amount-emitting luminance with the organic electroluminescent device manufactured above.

Preferably, the driving voltage of the device is determined by measuring the amount of current flowing through the device according to the change of the voltage, and the stability of the organic electroluminescent device manufactured by measuring the change in emission luminance with respect to the amount of current flowing through the device is determined. That's the way.

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

The organic-inorganic hybrid organic electroluminescent device of the present invention comprises a hole injection-transport material in the pores of an inorganic mesoporous molecular sieve film having a very high surface area and having pores arranged regularly in nanometer size. Therefore, the organic material responsible for hole injection-transport can be well dispersed, and the hole injection-transport organic material can be surrounded by inorganic walls to increase thermal and mechanical stability, and can be highly compared with devices manufactured with similar materials. It has hole mobility, low drive voltage and thermal and mechanical stability.

The inorganic mesoporous molecular sieve film may be obtained through a known method, and preferably may be obtained using an inorganic source selected from a silica source, an organic hybrid silica source, or a titanium oxide source as a pore wall forming material. have.

Specific examples of the silica source include tetraethoxysilane (TEOS), and specific examples of the organic hybrid silica source include 1,2-bis (trimethoxysilyl) ethane and 1,4-bis (triethoxysilyl ) Benzene or 1,2-bis (trimethoxysilyl) ethene. In addition, specific examples of the titanium oxide source include tetrachloro titanium or titanium isopropoxide.

An example of the preparation of an inorganic mesoporous molecular sieve film having a very high surface area and regular pores of nanometer size is schematically illustrated in FIG. 1. In FIG. 1, the silica source is used as the inorganic source, but the present invention is not limited thereto.

As shown in FIG. 1, the inorganic mesoporous molecular sieve has a sol-gel and a self-assembly process using an inorganic source (for example, a silica circle) as a pore wall forming material, and using a surfactant or a block copolymer as a template. To form a template hybrid with silica.

At this time, one example of a surfactant that can be used as a template is CH ₃ (CH ₂ ) ₁₁ N (CH ₃ ) ₃ Br, CH ₃ (CH ₂ ) ₁₅ N (CH ₃ ) ₃ Br, CH ₃ (CH ₂ ) ₁₇ N (CH _{3) 3} Br and the like, an example of the block copolymer is poly (ethylene oxide) poly (propylene oxide) - poly (ethylene oxide) triple copolymer (poly (ethylene oxide) of the - block -poly (propylene oxide ) - block -poly and the like (ethylene oxide), hereinafter "PEO-PPO-PEO block copolymers") and dual copolymer ((poly (etylene oxide-poly (ethylethylene), PEO-PEE), to preferably And PEO-PPO-PEO block copolymers having a number average molecular weight of about 13400.

As described above, the formation of the silica and the template hybrid is performed in an acidic atmosphere. When the hybrid is formed, the solution is added to the support and then rotated at high speed to form a thin film. Then, after drying at about 80 to 100 ℃, calcination (calcine) at 450 ℃ to remove the mold, the inorganic system having a silica wall, a surface area of more than 1000 m 2 / g surface area and nano-sized and regularly arranged pores A mesoporous molecular sieve film can be obtained.

As shown in Fig. 2, the silica source used as the pore wall forming material, specifically tetraethoxysilane as the pore wall forming material, shows that the tetraethoxy silane is preferably dissolved in aqueous solution and Decomposition reaction (step 1) is followed by dehydration between silanols to form -Si-O-Si- bonds (step 2), and finally they are crosslinked to form pore walls (step 3). As a result, the skeleton of the pores is in the form of an oxide and has hydroxyl groups on the surface of the pores.

The inorganic mesoporous molecular sieve film thus formed may have a pore array of a hexagonal, cubic, layered or disordered structure, as shown in FIG. 3.

Based on the inorganic-based mesoporous molecular sieve film synthesis technology, as shown in FIG. 4, a vacuum is used to incorporate TPD, a hole injection-transport material, into the mesoporous silica film pores coated on an indium-tin oxide (ITO) glass plate. It is preferable to use a solution supporting method rather than a thermal vapor deposition method.

And preferably, as the hole injection-transport layer material, TPD ( N, N'- Bis ( m -tolyl) -1,1'-biphenyl-4,4'-diamine), MEH-PPV (Poly [2-methoxy- 5- (2'-ethylhexyloxy) -p -phenylene vinylene]), CuPc (Copper phthalocyanine), PEDT / PSS (Poly (3,4-ethylenedioxythiophene) -poly (styrene)), TDAB (1,3,5-Tris) (diphenylamino) benzene), PVK (Polyvinylcarbazole), PF (Polyfluorene).

In order to incorporate TPD, which is a hole injection-transport material, into the mesoporous silica film pores, a concentration of 3 wt% chloroform solution is appropriate. If a thinner concentration is used, the amount of TPD incorporated into the pores is less. If a higher concentration is used, it is inefficient due to waste of TPD.

As shown in FIG. 4, Alq3, an electron injection-transport material, and aluminum (Al), a cathode, are deposited on a TPD-incorporated inorganic mesoporous silica molecular sieve by a high vacuum thermal evaporation method to form an organic-inorganic hybrid organic electroluminescent device. It can manufacture.

As such, the electron injection-transport material is preferably Alq3 (Tris (8-hydroxyquinolinato) aluminum), PBD (2-Biphenyl-4-yl-5- (4- t -butylphenyl) -1,3,4-oxadiazole), TPBI () 2,2 ', 2''-(Benzene-1,3,5-triyl) -tris (1-phenyl-1 H -benzimidazole), BCP (2,9-Dimethyl-4,7-diphenyl- 1,10-phenanthroline). Also, the negative electrode material is preferably selected from Al, Ag-Mg, Al-Ca, Al-Li, AlLiF.

The performance of the device can be known by measuring the hole mobility, the voltage-current, the voltage-luminescence, and the amount of light-emitting luminance of the organic electroluminescent device.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1

Preparation of mesoporous silica solution with regular hexagonal pore arrangement by self-assembly of triple polymer and tetraethoxysilane

5 is a flowchart showing a process of preparing a silica solution having mesopores according to one embodiment of the present invention. In describing the preparation of the silica solution having mesopores with reference to this, first, 1.0 × 10 ^-2 mol of a tripolymer (PE ₁₀₆ PO ₇₀ PE ₁₀₆ ) is dissolved in a solution of 12 mol of distilled water and 60 mol of ethanol (step S51). ). To this was added 3.0 × 10 ⁻² mol of 35 wt% hydrochloric acid (step S52). Stir until a homogeneous solution at room temperature. Then, 1 mol of tetraethoxysilane (TEOS) was added (step S53). Stir at room temperature for 2 hours. Finally, the self-assembly of the triple polymer and tetraethoxysilane yielded a mesoporous silica solution having a regular hexagonal pore arrangement (step S54).

Synthesis of Silica Films with Mesopores on Indium-Tin Oxide (ITO) Coated Glass

FIG. 6 is a flowchart illustrating a process of synthesizing a silica film having a pore arrangement of a regular hexagonal structure with mesopores on an indium-tin oxide (ITO) -coated glass sheet according to an embodiment of the present invention. Referring to this, the process of synthesizing a silica film (MS) having mesopores on an indium-tin oxide-coated glass sheet is described below. First, an indium-tin oxide (ITO) -coated glass sheet (4 mm in a 2 mm x 20 mm glass sheet) is described. A glass plate coated with an indium-tin oxide line having a width of 2 mm at intervals is prepared (step S61). First, the prepared mesoporous silica solution is added onto an indium-tin oxide coated glass plate (step S62). The glass plate is rotated at 6000 rpm for 50 seconds (step S63). Then, it was dried at 80 ° C. for 2 hours (step S64). And an indium-tin oxide coated with a mesoporous silica film (MS) having a surface area of at least 1000 m 2 / g and a regular hexagonal pore arrangement with calcination at 450 ^o C for 4 hours. A glass plate was obtained (steps S65 and S66).

Incorporation of TPD into the pores of the mesoporous silica film coated on an indium-tin oxide (ITO) glass plate

7 is a flow chart showing the incorporation process of TPD in the pores of the mesoporous silica film (MS) coated on the indium-tin oxide (ITO) glass plate according to an embodiment of the present invention. First, 3 wt% N, N'-diphenyl-N, N'-bis (3-methylphenyl) -1,1-biphenyl-4,4'-diamine (TPD) is dissolved in chloroform solution (step S71). In this solution, an indium-tin oxide glass plate coated with a mesoporous silica film (MS) is dipped (step S72). Shake for 8 hours at room temperature. Then, the glass plate is taken out and rotated at 5000 rpm for 5 seconds (step S73). Then, dry at 40 ^° C. for 12 hours. Finally, the thickness of the mesoporous silica film (MS) coated on the indium-tin oxide (ITO) glass plate and including TPD in the pores was 110 nanometers.

Organic-Inorganic Hybrid Hall Transport layer  Fabrication of Organic Electroluminescent Device with Eggplant

8 is a flowchart illustrating a manufacturing process of an organic electroluminescent device having an organic-inorganic hybrid hole transport layer according to an embodiment of the present invention. Indium-tin oxide (ITO) coated glass plates are commercially available. First, the Alq3 was coated on an indium-tin oxide (ITO) glass plate and included TPD in the pores under different vacuum thicknesses of 50, 70, and 100 nanometers of Alq3 under a vacuum of 5 x 10 ^-6 Torr. Vapor deposition (step S81). And aluminum is deposited under a vacuum of 5 x 10 ^-6 Torr (step S82). Then, gold wires are connected to the indium-tin oxide (ITO) layer and the deposited aluminum layer to complete an organic electroluminescent device having an organic-inorganic hybrid hole transport layer (steps S83 and S84).

Identification and evaluation of product

FIG. 9 shows a scanning electron micrograph of a sample in which a mesoporous silica film (MS) was formed on an indium-tin oxide (ITO) coated glass plate. From this, it was confirmed that the mesoporous film was well formed with a constant thickness of 110 nanometers. And it was confirmed that the pores of the mesoporous silica film (MS) were well formed throughout the sample, as shown by the black dots representatively shown in the red circle from the edge of the enlarged film (lime green square part).

10 shows the X-ray diffraction pattern of the mesoporous silica film (MS) sample. According to the results of FIG. 10, as shown in the characteristic peaks of (100) and (200), the pores in the mesoporous silica film sample had a hexagonal structure and arranged in parallel with an indium-tin oxide (ITO) coated glass plate. Shows a very regular array.

11 is a transmission electron micrograph of a sample of mesoporous silica film (MS). From this result, it can be directly confirmed that the pores in the mesoporous silica film sample have a regular size and are arranged regularly. And this result is in good agreement with the result of the x-ray diffraction pattern in FIG.

12 shows an atomic force micrograph of the surface of the mesoporous silica film (MS) sample. This result shows directly that two-dimensionally arranged pores having a certain size on the surface of the mesoporous silica film (MS) sample. These results are in good agreement with the results of the X-ray diffraction pattern, which shows that uniformly sized mesopores are arranged parallel to the indium-tin oxide (ITO) coated glass plate.

FIG. 13 is a nitrogen adsorption / desorption curve of a sample of mesoporous silica film (MS), which shows the curve for a typical mesoporous molecular sieve. From the pore distribution (inserted graph), it was confirmed that pores having a constant size of 7 nanometers were distributed in the sample.

FIG. 14 is x-ray photoelectron spectroscopy data for a sample of mesoporous silica film (TIMS) in which TPD is incorporated into pores on an indium-tin oxide (ITO) coated glass plate. This data shows the content of elements by depth for the sample. From this result, when the depth reaches 110 nanometers, it can be seen that as the indium element contained in the indium tin oxide (ITO) as a support, the mesoporous silica film has a thickness of 110 nanometers. This result is in agreement with the results confirmed by the scanning electron microscope. And most of the carbon (C) and nitrogen (N) atoms that can be identified by TPD, the hole injection-transport material incorporated into the pores, were identified up to 110 nanometers in depth. Thus, it can be seen that TPD is well dispersed in the pores of the entire mesoporous silica film.

Example 2:

Hole injection With transport layer TPD Voltage-Current-Luminous Measurement and Excellent Performance and Device Stability of Organic-Inorganic Hybrid Organic Electroluminescent Devices Containing Mixed-porous Silica Films

FIG. 15 is an organic-inorganic hybrid organic electroluminescent device in which all of the mesoporous silica, the electron injection-transport material (Alq3), and Al, which are TPDs, are incorporated into pores on a glass plate coated with indium-tin oxide (ITO). It is the data that measured the instantaneous light current by time difference analysis. From this result, the hole mobility of the device showed a value of 1.02 × 10 ^-10 cm ² V ^-1 s ^-1 and confirmed that it is a value required by the present invention.

Fig. 16 shows the amount of current with respect to voltage (Fig. 16 (A)) and the luminescence with respect to voltage (Fig. 16 (B)), respectively. In the interpolated graph of FIG. 16 (A), when the hole injection-transport layer consists of only the mesoporous silica film in the device or when the TPD, which is a hole injection-transport material, is coated on the mesoporous silica film layer, it has the same properties as the insulator. As the voltage increases, no current flows. On the other hand, a device composed of a mesoporous silica film (TIMS) in which TPD is dispersed in pores as a hole injection-transport layer shows a change in the amount of current flowing as the voltage changes, thereby acting as a semiconductor layer in the organic electroluminescent device. Shows. 16 (A) and 16 (B), the Alq3 of Alq3 has a thickness of 110 nanometers in which the TPD incorporating the hole injection-transport layer from the voltage-current and voltage-luminescence characteristics is 110 nanometers. The thickness shows that 70 nanometers is most suitable. Further, as shown in the results of Figs. 16 (A) and 16 (B), under the same current or luminescence, the device in which the hole injection-transport layer is composed of a TPD-interporous silica film (TIMS) (Fig. 16 (A) (b)) And (b) and (b) of FIG. 16, the driving voltage is significantly lower than that of the TPD device manufactured by the conventional method. These results show that the TPD-porous silica film (TIMS) layer controls the hole flow in the device.

As shown in FIG. 16 (B), the device (FIG. 16 (B) (a), (b), (c)) in which the hole injection-transport layer is composed of TPD-interporous silica film (TIMS) is used in the conventional method. The stability of the device is shown to show luminescence at a higher voltage (especially at 30 V or higher) than the device composed only of TPD manufactured by FIG. 16 (d), (e), (f).

As shown in FIG. 17, the current efficiency of the device (FIG. 17 (b)) in which the hole injection-transport layer is composed of TPD-interporous silica film (TIMS) is shown in FIG. 17 (FIG. Comparable to d) and (e)).

As shown in the Commission Internationale de l'Eclairage (CIE) color coordinate system of FIG. 18, as the hole injection-transport layer increases with the voltage up to 32 V for a device comprised of TPD-porous silica film (TIMS), (0.31, From 0.56) to (0.32, 0.55) with little change. This result is consistent with the results for the stability of the device in Fig. 17 (b), which shows strong luminescence even at high voltages.

Although the above has been described with reference to a preferred embodiment of the present invention, various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the scope of the present invention should not be limited to the above embodiments, but should be determined by the claims described below.

As described in detail above, the present invention provides a single hole injection-transport layer in which an organic material responsible for hole injection-transport is well dispersed in a silica mesoporous molecular sieve having a very high surface area and having pores arranged regularly in nanometer size. By using it can improve the performance of the organic electroluminescent device using the same.

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In addition, the hole injection-transport organic material may be surrounded by an inorganic material wall, thereby improving thermal and mechanical stability of the organic electroluminescent device using the same.

In addition, by using a well-known and relatively inexpensive material of the conventional hole injection-transport organic material, it is possible to improve the performance of the existing organic electroluminescent device and reduce the manufacturing cost of the device.

Claims (12)

Inorganic mesoporous molecular sieve characterized in that the surface area is 1000 m 2 / g or more, the nanometer size and the arrangement structure has regular pores, and the hole injection-transport material is incorporated into the pores to form a layer film. delete delete delete delete Forming an inorganic / template hybrid solution using a source of inorganic material as a pore wall forming material and undergoing self-assembly with a sol-gel using a surfactant or a block copolymer as a mold; Rotating the inorganic / template hybrid solution on the support at high speed to form a thin film; And Drying and calcining the thin film (calcine) to remove the mold to obtain the molecular sieve film of claim 1, wherein the method for producing an inorganic mesoporous molecular sieve film. delete The method according to claim 6, The surfactant may be CH ₃ (CH ₂ ) ₁₁ N (CH ₃ ) ₃ Br, CH ₃ (CH ₂ ) ₁₅ N (CH ₃ ) ₃ Br, or CH ₃ (CH ₂ ) ₁₇ N (CH ₃ ) ₃ Br Including, Wherein the block copolymer is poly (ethylene oxide) poly (propylene oxide) - poly (ethylene oxide) triple copolymers of (poly (ethylene oxide) - block -poly (propylene oxide) - block -poly (ethylene oxide)), or Method for producing an inorganic mesoporous molecular sieve film comprising a double copolymer (poly (etylene oxide-poly (ethylethylene))). delete delete delete An organic-inorganic hybrid organic electroluminescent device, comprising using the inorganic mesoporous molecular sieve film of claim 1 as one hole injection-transport layer.

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