JP2008269923A - Manufacturing method of multi-color light-emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a multi-color light-emitting device of a color conversion system by selectively forming a color conversion layer precisely, without using a metal mask having a problem in precision. <P>SOLUTION: The manufacturing method of a multi-color light-emitting device includes a color-filter forming process forming color filters made by independently arranging two or more kinds of filters which transmit light of different wavelength regions respectively on a transparent substrate, a flattened layer forming process forming a flattened layer 5 on the color filter formed at the color-filter forming process, an adhesion prevention layer forming process forming layers functioning as an adhesion prevention layer 6 by a desired pattern with low affinity to a color conversion layer on an upper face of the flattened layer formed at the flattened layer forming process, and a color conversion layer forming process forming a color conversion layer absorbing light with a certain wavelength and outputting light containing a different wavelength from the absorbed wavelength by a deposition method, on the flattened layer and the adhesion prevention layer formed by the desired pattern on it. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a multicolor light emitting device.

  In recent years, organic EL devices have been actively researched for practical use. Organic EL elements are expected to achieve high luminance and luminous efficiency because they can achieve high current density at low voltage, and the practical application of organic multi-color EL displays capable of high-definition multi-color or full-color display is expected. Expected.

  As an example of a method for making the organic EL display multi-colored or full-colored, there is a method using a plurality of types of color filters that transmit light in a specific wavelength region (color filter method). When applying the color filter method, the organic EL element used emits multicolor light and includes the three primary colors of light (red (R), green (G), and blue (B)) in a balanced manner, so-called “white light”. "Is required to emit light.

  In order to obtain a multicolor organic EL device, a light emitting layer containing a plurality of light emitting dyes is used, a method for simultaneously exciting the plurality of light emitting dyes, a light emitting layer containing a host light emitting material and a guest light emitting material, and a host light emission. A method of exciting and emitting a material, and simultaneously transferring energy to the guest material and emitting light, a method of exciting a luminescent dye in each layer using a plurality of luminescent dyes, and a luminescent layer containing a luminescent dye And a carrier transport layer containing a light-emitting dopant adjacent to the light-emitting layer, and a method for transferring a part of the excitation energy from the excitons generated by carrier recombination in the light-emitting layer to the light-emitting dopant, etc. It is coming.

  However, the above-described multicolor light-emitting organic EL device relies on either exciting a plurality of types of light-emitting materials at the same time or transferring energy between the plurality of types of light-emitting materials. In such an element, it has been reported that the emission intensity balance between the light emitting materials changes and the obtained hue may change as the driving time elapses or the energization current changes.

  As another method for obtaining a multicolor organic EL element, a color conversion method using a monochromatic organic EL element and a color conversion film has been proposed. The color conversion film used is a layer that contains one or more color conversion materials that absorb light of short wavelengths and convert it to light of longer wavelengths. As a method for forming a color conversion film, it has been studied to apply a coating liquid in which a color conversion material is dispersed in a resin, or to deposit the color conversion material by a dry process such as vapor deposition or sputtering. .

  However, when the concentration of the color conversion material in the color conversion film increases, a phenomenon called concentration quenching occurs in which the absorbed energy is deactivated without light emission while repeating the movement between the same molecules. In order to suppress this phenomenon, a color conversion substance is dissolved or dispersed in some medium to reduce the density (see Patent Document 1).

  Here, when the concentration of the color conversion substance is lowered, the absorbance of light to be absorbed decreases, and sufficient converted light intensity cannot be obtained. With respect to this problem, for example, the color conversion film is made thick so as to have a thickness of about 10 μm to increase the absorbance and maintain the color conversion efficiency. When such a thick color conversion film is used, disconnection of the electrode pattern at the stepped portion, difficulty in achieving high definition, residual moisture or solvent in the film (residual moisture when combined with an organic EL element) Or, the organic EL layer is altered by the solvent, resulting in a display defect). On the other hand, from the viewpoint of reducing the viewing angle dependency, there is a request that is contrary to the idea of increasing the film thickness to reduce the color conversion film.

  Therefore, in order to provide a color conversion film capable of maintaining sufficient converted light intensity without increasing the thickness, a host-guest color conversion film having a film thickness of 2 μm or less is formed by vapor deposition. (See, for example, Patent Document 2).

  In addition, as a patterning method for the thick film color conversion layer, an uneven pattern is formed on the support substrate, a color conversion material is applied to the uneven pattern portion, the color conversion material is embedded in the recess, and then the color conversion layer is polished. A method of patterning by flattening the surface has been studied (for example, see Patent Document 3).

Patent Document 4 proposes a method of manufacturing an optical element in which a lyophilic portion having a predetermined pattern is formed on a substrate, and a portion other than the lyophilic portion on the substrate is a lyophobic portion. This lyophilic part is formed, for example, by applying a hydrophilic solvent having a specific surface tension containing an optical element material. That is, by using a hydrophilic solvent having a specific surface tension, the solvent does not flow to an unnecessary portion, and does not become spherical and uneven.
JP 2000-230172 A JP 2002-75643 A JP 2006-32021 A JP 2006-16579 A Japanese Patent Publication

  However, when a color conversion film is formed by vapor deposition as in Patent Document 2, if a film is formed on the entire display surface, the three primary colors cannot be emitted separately. Corresponding fine pattern formation is required. At present, as a method of patterning a deposited thin film, there is a coating method using a metal mask.

  However, the vapor deposition pattern forming method using a metal mask has been put into practical use for a long time. However, the fineness level of 150 ppi is the limit for the miniaturization of the mask pattern due to the limit due to the mask material and the thickness. For high-definition patterns, there are problems that the difficulty increases, the area is not reached, and the yield is lowered.

  Further, the method described in Patent Document 3 cannot be applied to a color conversion layer formed by a vapor deposition method. Since the color conversion layer formed by the vapor deposition method is affected by moisture and oxygen, a barrier layer is required.

  Furthermore, in the method of Patent Document 4, since water is used as the coating liquid, a baking process at a high temperature for removing the water component from the coating liquid is necessary to form a pattern, and the optical element material in the coating liquid Deterioration is assumed. In addition, the residual water component may enter the light emitting element and have a short life.

  An object of the present invention is to provide a method of manufacturing a color conversion type multicolor light emitting device by finely and selectively forming a color conversion layer without using a metal mask having a problem in definition.

That is, the method for manufacturing a multicolor light emitting device according to the present invention is a color filter formation in which a color filter is formed by independently disposing two or more types of filters that transmit light in different wavelength ranges on a transparent substrate. Process,
A flattening layer forming step of forming a flattening layer on the upper surface of the color filter formed in the color filter forming step;
An adhesion preventing layer forming step of forming a layer having a desired pattern on the upper surface of the planarizing layer formed in the planarizing layer forming step, which has a low affinity for the color conversion layer and functions as an adhesion preventing layer;
A color conversion layer that absorbs light of a certain wavelength and outputs light having a wavelength different from the absorbed wavelength is formed on the planarization layer and an adhesion preventing layer formed in a desired pattern on the flattening layer by an evaporation method. And a color conversion layer forming step.

  By using the method for manufacturing a multicolor light emitting device of the present invention, the color conversion layer can be selectively formed finely, and a high-definition panel can be manufactured.

  Hereinafter, the manufacturing method of the multicolor light emitting device of the present invention will be described with reference to FIGS.

  In the multicolor light emitting device manufactured by the method for manufacturing a multicolor light emitting device of the present invention, for example, a color filter 30 is provided on a substrate 10 as shown in FIG. The substrate 10 used in the method for producing a multicolor light emitting device of the present invention is rich in light transmittance, and is used for forming a black mask, a color filter layer, a color conversion layer, etc., an anode and a light emitting layer (solvent, temperature). Etc.), and is preferably excellent in dimensional stability. Moreover, what is necessary is just to be what does not cause a performance fall to a multicolor light-emitting device, and glass, various plastics, various films etc. are mentioned as an example.

  The color filter 30 used in the present invention may be a color filter used for a flat panel display such as a liquid crystal display. In recent years, a pigment dispersion type color filter in which a pigment is dispersed in a photoresist is often used.

  The color filter 30 for a flat panel display includes a blue color filter 30B that transmits a wavelength of 400 nm to 550 nm, a green color filter 30G that transmits a wavelength of 500 nm to 600 nm, and a red color filter 30R that transmits a wavelength of 600 nm or more. An array is common.

  Further, for the purpose of mainly improving the contrast, it is a general practice to dispose a black matrix 40 that does not transmit the visible range between the pixels formed by the color filters.

  The substrate 10 on which the color filter 30 is provided is covered with the planarization layer 5. The flattening layer 5 is provided for the purpose of protecting the color filter and for the purpose of smoothing the film surface, and has a high light transmittance and can be provided without deteriorating the color filter. And you need to choose a process.

Planarizing layer 5 to enhance the adhesion to the color conversion layer 20 formed on the upper, CH groups on the surface of the planarizing layer, CH _x groups, it is desirable that the material CO groups are often formed. Although the detailed mechanism is currently under analysis, it is thought that having many of these groups lowers the binding potential of the color conversion layer material due to the Coulomb force and increases the affinity.

  Applicable materials are generally those in which a photocurable or photothermal combination type curable resin is subjected to light and / or heat treatment to generate radical species or ionic species to be polymerized or crosslinked to be insoluble and infusible. It is. Further, it is desirable that the photocurable or photothermal combined type curable resin is soluble in an organic solvent or an alkaline solution before curing for patterning.

  Specifically, the photocurable or photothermal combination type curable resin means (1) a composition film composed of an acrylic polyfunctional monomer and oligomer having a plurality of acryloyl groups and methacryloyl groups, and light or a thermal polymerization initiator. Heat treated to generate photo radicals and heat radicals for polymerization, (2) A composition comprising polyvinyl cinnamate ester and sensitizer dimerized by light or heat treatment, and (3) chain A composition film composed of a cyclic or cyclic olefin and bisazide is generated by light or heat treatment to generate nitrene and crosslinked with the olefin, and (4) a composition film composed of a monomer having an epoxy group and a photoacid generator is subjected to light or heat treatment. In other words, the acid (cation) is generated and polymerized. In particular, the photocurable or photothermal combination type curable resin (1) can be patterned with high definition, and is preferable in terms of reliability such as solvent resistance and heat resistance.

  Others such as polycarbonate (PC), polyethylene terephthalate (PET), polyethersulfone, polyvinyl butyral, polyphenylene ether, polyamide, polyetherimide, norbornene resin, methacrylic resin, isobutylene maleic anhydride copolymer resin, cyclic olefin Thermoplastic resins, epoxy resins, phenol resins, urethane resins, acrylic resins, vinyl ester resins, imide resins, urethane resins, urea resins, melamine resins, and other thermosetting resins, or polystyrene, polyacrylonitrile, polycarbonate, etc. A polymer hybrid containing a trifunctional or tetrafunctional alkoxysilane can also be used.

  On the flattening layer 5, an adhesion preventing layer 6 is disposed in a predetermined pattern for patterning the color conversion layer. A color conversion layer 20 is provided on the flattening layer 5 where the adhesion preventing layer 6 is not provided.

  The adhesion preventing layer 6 is provided for patterning of the color conversion layer 20, and it is necessary to select a material and a process that are rich in light transmission and can be provided without deteriorating the planarizing layer 5. . The film thickness of the adhesion preventing layer is set to a film thickness capable of photolithography, preferably 0.3 to 10 um, and more preferably, in order to reduce the film thickness difference between the formed part and the non-formed part of the color conversion layer. 0.3-3um is good.

  As an applicable material, a photocurable or photothermal combination type curable resin is generally insoluble and infusible by light and / or heat treatment to generate radical species and ionic species to be polymerized or crosslinked. It is. Further, it is desirable that the photocurable or photothermal combination type curable resin is soluble in an organic solvent or an alkaline solution before curing for patterning. Examples of the photocurable or photothermal combined type curable resin used here include the resins (1) to (4) described in the section of the planarization layer. In addition, phenol resins, fluororesins, fluorosilane coupling materials, fluoroisocyanate silane materials, and the like can also be used.

The adhesion preventing layer 6 desirably has an OH group or F in the side chain or main chain in order to reduce adhesion with the color conversion layer. On the surface of the flattening layer 5, many CH groups, CH _x groups, and CO groups are formed and the adhesion is increased. On the other hand, the presence of OH groups and F increases the bonding potential due to the Coulomb force with the color conversion layer material. This is probably because the affinity is lowered.

  In order to confirm the above reasoning, when the detection ratio of OH group and CH group on the surface of the adhesion preventing layer was examined by Raman spectroscopy, the peak intensity indicating OH bond was 0.5 or more of the peak intensity indicating CH bond. When shown, it was possible to easily peel off the color conversion material. In the case of F, it was possible to easily peel the color conversion material when the detection ratio was 0.2% or more with respect to the detection amount of C by analyzing the composition ratio by ESCA.

  The color conversion layer 20 is a layer formed from one or more color conversion dyes, and preferably has a thickness of 1 μm or less, more preferably 200 nm to 1 μm. Further, the thickness of the color conversion layer remaining on the adhesion preventing layer is desirably 50 nm or less in order to suppress absorption of wavelengths of blue and green components and obtain sufficient transmission. The color conversion layer 20 is formed by a dry process, preferably a vapor deposition method (including resistance heating and electron beam heating). When the color conversion layer 20 is formed using a plurality of types of color conversion dyes, a preliminary mixture obtained by mixing a plurality of types of color conversion dyes at a predetermined ratio may be prepared in advance, and co-evaporation may be performed using the preliminary mixture. Good. Alternatively, a plurality of types of color conversion dyes may be disposed in separate heating portions, and the respective color conversion dyes may be separately heated to perform co-evaporation. In particular, the latter method is effective when there is a large difference in characteristics (evaporation rate, vapor pressure, etc.) among a plurality of types of color conversion dyes.

  The color conversion dye absorbs light in the near ultraviolet region or visible region emitted from a light source, performs wavelength distribution conversion, and emits visible light having a different wavelength. It is particularly preferable to absorb light in the blue or blue-green region. The emission wavelength of the color conversion layer is preferably in the range of 500 to 550 nm for the green conversion layer and 600 to 700 nm for the red conversion layer.

Examples of the color conversion dye for forming the color conversion layer include aluminum chelate dyes such as Alq3; 3- (2-benzothiazolyl) -7-diethylaminocoumarin (coumarin 6), 3- (2-benzimidazolyl) -7-diethylamino Coumarin dyes such as coumarin (coumarin 7) and coumarin 135; naphthalimide dyes such as solvent yellow 43 and solvent yellow 44; 4-dicyanomethylene-2-methyl-6- (p-dimethylaminostyryl) -4H- Cyanine dyes such as pyran (DCM-1, (I)), DCM-2 (II), and DCJTB (III); xanthene dyes such as rhodamine B and rhodamine 6G; pyridine dyes such as pyridine 1; -Difluoro-1,3,5,7-tetraphenyl-4-bora-3a, 4a-dia -s- indacene (IV), Lumogen F Red, or the like can be used Nile red (V). Moreover, you may use the host-guest material currently used for the light emitting layer of various well-known EL. As described above, the color conversion material that can be easily peeled off by the adhesion preventing layer 6 includes many CH ₃ groups at its end.

  The barrier layer 4 is provided so as to cover the planarization layer 5 on which the adhesion preventing layer 6 and the color conversion layer 20 are formed. That is, since the color conversion dye forming the color conversion layer 20 is an organic substance, it is vulnerable to moisture and oxygen. Therefore, it is necessary to protect the color conversion dye from moisture and oxygen. This barrier layer 4 is provided to protect the color conversion dye from moisture and oxygen.

As a material constituting the barrier layer 4, the barrier layer 4 has electrical insulation, has barrier properties against gases and organic solvents, and has high transparency in the visible range (transmittance of 50% or more in the range of 400 to 700 nm). On the layer, a material having a film hardness of preferably 2H or more can be used as the hardness that can withstand the film formation of the anode. For example, inorganic oxides such as SiO _x , SiN _x , SiN _x O _y , AlO _x , TiO _x , TaO _x , ZnO _x , inorganic nitride, and the like can be used. The barrier layer described above may be a single layer or a stack of a plurality of layers.

On the barrier layer 4, a transparent electrode 2, an organic EL layer 3, and a cathode 1 are laminated in this order.
The transparent electrode is made of ITO, tin oxide, indium oxide, IZO, zinc oxide, zinc-aluminum oxide, zinc-gallium oxide, or a conductive transparent metal obtained by adding a dopant such as F or Sb to these oxides. It can be formed using an oxide.

  The organic EL layer 3 includes at least an organic light emitting layer, and has a structure in which a hole injection layer, a hole transport layer, an electron transport layer and / or an electron injection layer are interposed as required. Specifically, an organic EL element having the following layer structure is adopted (the anode and the cathode are either a reflective electrode or a transparent electrode).

(1) Anode / organic light emitting layer / cathode (2) Anode / hole injection layer / organic light emitting layer / cathode (3) Anode / organic light emitting layer / electron injection layer / cathode (4) Anode / hole injection layer / organic Light emitting layer / electron injection layer / cathode (5) Anode / hole transport layer / organic light emitting layer / electron injection layer / cathode (6) Anode / hole injection layer / hole transport layer / organic light emitting layer / electron injection layer / Cathode (7) Anode / hole injection layer / hole transport layer / organic light emitting layer / electron transport layer / electron injection layer / cathode

  As a material of each layer constituting the organic EL layer, known materials are used. Moreover, each layer which comprises an organic EL layer can be formed using the arbitrary methods known in the said techniques, such as a vapor deposition method. For example, as the material of the organic light emitting layer for obtaining blue to blue-green light emission, for example, fluorescent whitening agents such as benzothiazole, benzimidazole, and benzoxazole, metal chelated oxonium compounds, styrylbenzene compounds, Materials such as aromatic dimethylidin compounds are preferably used. Further, if necessary, white light emission may be used. In that case, a known red dopant is used. In the case of a green conversion layer, a blue-red EL spectrum is desirable.

Next, the manufacturing method of a multicolor light emitting device is further demonstrated using FIG.
FIG. 2A is a diagram illustrating a state in which the planarization layer 5 is formed so as to cover the color filters 30R, 30G, and 30B provided on the substrate 10 and the black matrix 40 provided therebetween. Since the planarization layer 5 has not only the purpose of protecting the color filter 30 but also the purpose of smoothing, it is generally formed by a coating method.

  FIG. 2B is a diagram showing a state in which the adhesion preventing layer 6 is arranged in a predetermined pattern on the planarizing layer 5 formed in (1) for patterning the color conversion layer. The adhesion preventing layer is applied to the entire surface of the planarizing layer by a coating method such as spin coating, and after prebaking, a high-pressure mercury lamp is irradiated to transfer a photomask pattern to form a predetermined pattern.

  FIG. 2 (3) is a diagram showing a state in which the color conversion layer 20 is formed in a portion of the planarization layer 5 where the adhesion preventing layer 5 is not formed. In FIG. 2 (3), the color conversion layer is the red conversion layer 20R, and is provided at the position where the red color filter 30R is provided.

  When an organic EL layer that emits light in the blue or blue-green region is used as a light source, if light from the organic EL layer is passed through a simple red filter to obtain light in the red region, light of the wavelength in the red region is originally emitted. This is because the output light becomes extremely dark due to the small amount. By converting the wavelength distribution of light in the blue or blue-green region into red light by the red conversion layer, it is possible to output light in the red region having sufficient intensity.

  The color conversion layer is formed on the entire surface without using a metal mask, or is formed by vapor deposition using a metal mask having a simple opening.

It is desirable that an ultrasonic transducer is connected to the substrate on which the color conversion layer is deposited via a support portion of the substrate. During the color conversion layer deposition process, the color conversion material deposited on the adhesion preventing layer can be peeled by vibrating the substrate at regular intervals.
A commercially available ultrasonic transducer can be used, and its frequency is 20 to 25000 kHz. In order to prevent detachment from the support portion of the substrate, the frequency is 900 to 2500 KHz. It is desirable to use

Alternatively, the film deposited on the adhesion preventing layer can be removed by spraying Ar, He, N 2, or CO ₂ gas onto the substrate after forming the color conversion layer. The pressure of the gas to be sprayed can be 0.1 to 15 MPa, but is preferably 0.1 to 5 MPa in order to remove only the film deposited on the adhesion preventing layer.

  Alternatively, the film deposited on the adhesion preventing layer can be removed by passing an adhesive tape or roller over the substrate after forming the color conversion layer. The adhesive strength of the adhesive tape or roller is preferably 0.01 to 1 N / cm, and the adhesive strength is 0.01 to 0.5 N / cm to remove only the film deposited on the adhesion preventing layer. Is more desirable. There is no restriction | limiting in particular in the material of an adhesive material, It is desirable that there is no remainder of an adhesive material on a pattern. Acrylic materials or the like can be used.

FIG. 2 (4) is a diagram showing a state in which the barrier layer 4 is formed so as to cover the adhesion preventing layer 6 and the color conversion layer 20 formed on the planarizing layer 5.
Color conversion dyes are organic and are vulnerable to moisture and oxygen. Therefore, it is necessary to protect the color conversion dye from moisture and oxygen, and a barrier layer 4 is provided as shown in FIG. There is no restriction | limiting in particular as a formation method of this barrier layer, It can form by methods, such as a sputtering method, CVD method, and a vacuum evaporation method.

  A transparent electrode 2 is formed on the barrier layer 4, and this transparent electrode is formed by vapor deposition, sputtering, or chemical vapor deposition (CVD), preferably by sputtering. The

<Example 1>
"Color filter"
On a 1737 glass (manufactured by Corning) having a thickness of 200 mm × 200 mm × 0.7 mm, a black matrix (CK-7001: manufactured by Fuji Film Electronics Materials), a red color filter (CR-7001: manufactured by Fuji Film Electronics Materials), A color filter was formed by a photolithographic method using a green color filter (CG-7001: manufactured by Fuji Film Electronics Materials) and a blue color filter (CB-7001: manufactured by Fuji Film Electronics Materials). The film thickness of each layer was 1 μm.

Each color filter layer was applied to a predetermined film thickness by spin coating, pre-baked at 90 ° C. for 120 seconds, and then exposed to light of 250 mJ / cm ^{2 at} 405 nm using an exposure machine using a high-pressure mercury lamp as a light source. The pattern was transferred to the photomask and developed using a developer containing KOH as a main component. Thereafter, post-baking was performed for 600 seconds on a 220 ° C. hot plate.

  The manufactured color filter has a subpixel size of 168 μm × 56 μm (definition 150 ppi), a gap between the subpixels of 10 μm in the vertical direction, 10 μm in the horizontal direction, and an opening size of 158 μm × 46 μm. The three sub-pixels (red, blue, and green) constitute one pixel, and 50 pixels are arranged in the vertical direction and 50 pixels are arranged in the horizontal direction to form one panel. This panel is arranged 5 × 5 in the glass plane.

"Planarization layer"
A flattening layer was formed on the upper surface of the color filter using NN810L manufactured by JSR. The thickness of the planarizing layer was 2 μm. It should be noted that the bonding portion for bonding to the external drive circuit at the panel end portion was subjected to patterning so that the bonding strength would be lowered if a planarizing layer was present, so that the bonding portion at the panel end portion was exposed.

That is, after applying a predetermined film thickness by spin coating, pre-baking at 100 ° C. for 120 seconds, using an exposure machine with a high-pressure mercury lamp as the light source, applying a light beam of 450 mJ / cm ^{2 at} 405 nm. Pattern transfer was performed, and development was performed using a developer containing TMAH as a main component. Thereafter, post-baking was performed for 900 seconds on a 220 ° C. hot plate, and sufficient curing was performed.

"Anti-adhesion layer"
Using NN810L made by JSR, a pattern having a pattern width of 120 μm and a pattern pitch of 168 μm was formed on the planarization layer. The film thickness of the adhesion preventing layer was 1 μm. An anti-adhesion layer was formed on top of the blue and green pixel locations.

That is, after applying a predetermined film thickness by spin coating, pre-baking at 100 ° C. for 120 seconds, using an exposure machine with a high-pressure mercury lamp as the light source, applying a light beam of 450 mJ / cm ^{2 at} 405 nm. Pattern transfer was performed, and development was performed using a developer containing TMAH as a main component. Thereafter, post-baking was performed at 150 ° C. for 900 seconds, and the post-baking temperature was set low, whereby curing was incomplete.

  By baking at 150 ° C., the residual solvent in the film was small, and the resin side chain was left in a high proportion of OH groups. The surface of the adhesion preventing layer and the planarizing layer was measured by Raman spectroscopy, and the detection ratio of CH group and OH group was compared. The detection ratio for binding was approximately 0 or less than 0.1, but was approximately 0.8 on the surface of the anti-adhesion layer.

"Color conversion layer"
A color conversion layer composed of Alq3 and DCM-2 was produced with a resistance heating vapor deposition apparatus. A color conversion film having a film thickness of 300 nm was produced by co-evaporation in which Alq3 and DCM-2 were heated in separate crucibles in the vapor deposition apparatus. At this time, the heating temperature of each crucible was controlled so that the deposition rate of Alq3 was 0.3 nm / s and the deposition rate of DCM-2 was 0.005 nm / s. The color conversion layer of this example contained 2 mol% DCM-2 based on the total number of constituent molecules of the color conversion layer (Alq3: DCM-2 molar ratio is 49: 1). A color conversion layer was uniformly formed on the planarization layer.

"Barrier layer"
Without breaking the vacuum, using a plasma CVD method using monosilane (SiH ₄ ), ammonia (NH ₃ ) and nitrogen (N ₂ ) as source gases in a plasma CVD apparatus, silicon nitride (SiN) having a film thickness of 1 μm Was deposited to form a barrier layer. Here, when depositing SiN, the substrate temperature was 100 ° C. or less.
From the film thickness measurement after the formation of the barrier layer, the film thickness of the portion without the adhesion preventing layer (on the planarization layer) was 300 nm. On the other hand, the film thickness of the color conversion layer on the adhesion preventing layer was about 50 nm, and it was not thick enough to function as a color conversion layer. Therefore, the color conversion layer was formed along the pattern shape formed using the adhesion preventing layer.

"Organic EL layer"
On the filter part manufactured as described above, an anode / organic light emitting element layer (three layers of hole transport layer / organic light emitting layer / electron injection transport layer) / cathode are sequentially formed to obtain a multicolor light emitting device. Obtained.

  That is, first, a transparent electrode (IZO) was formed on the entire upper surface of the barrier layer that forms the outermost layer of the filter portion by sputtering. After applying a resist agent “TFR-1250” (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) on IZO, patterning is performed by a photolithography method, and the light emitting portions (red, green, and blue) of each color are positioned. A first electrode (anode) having a stripe pattern with a width of 0.48 mm, a pitch of 0.168 mm, and a film thickness of 200 nm was obtained.

Next, the substrate on which the anode was formed was mounted in a resistance heating vapor deposition apparatus, and a hole transport layer, an organic light emitting layer, and an electron injection transport layer were sequentially formed without breaking the vacuum. During film formation, the internal pressure of the vacuum chamber was reduced to 1 × 10 ⁻⁴ Pa. As the hole transport layer, 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD) was laminated to a thickness of 50 nm. The light emitting layer was formed by laminating 30 nm of aluminum chelate (Alq3): DCJTB (0.5%). The electron injecting and transporting layer was formed by laminating 20 nm of aluminum chelate (Alq3).

  Then, using a mask that can obtain a stripe pattern with a width of 130 μm and a pitch of 168 μm perpendicular to the first electrode (IZO) line without breaking the vacuum, a 200 nm thick Mg / Ag (10: 1) (Weight ratio) layer was deposited to form a second electrode (cathode).

  The organic light-emitting device thus obtained was sealed using a sealing glass (not shown) and a UV curable adhesive in a dry nitrogen atmosphere (both oxygen and moisture concentrations of 10 ppm or less) in the group box. Table 1 shows the thickness of the color conversion layer on the adhesion prevention layer of the obtained multicolor light emitting device and the thickness of the color conversion layer formed on the planarization layer.

<Example 2>
A multicolor light emitting device was produced in the same manner as in Example 1 except that the method for forming the adhesion preventing layer was changed as follows.

"Anti-adhesion layer"
A pattern with a pattern width of 120 μm and a pattern pitch of 168 μm was formed on the planarization layer using a JSR JEM700R2. The film thickness of the adhesion preventing layer was 1 μm.
After applying to a predetermined film thickness by spin coating, pre-baking at 110 ° C. for 120 seconds, and then transferring the pattern of the photomask to 40 mJ / cm ^{2 at} 405 nm using an exposure machine using a high-pressure mercury lamp as the light source Then, development was performed using a developer containing TMAH as a main component. Thereafter, post-baking was performed at 180 ° C. for 900 seconds, and curing was incomplete, but the residual solvent in the adhesion preventing layer was small.

  The surface of the adhesion preventing layer and the flattening layer were measured by Raman spectroscopy, and the detection ratios of CH groups and OH groups were compared. On the surface of the adhesion preventing layer, the detection ratio of OH bond to CH bond was approximately 1.2.

  From the measurement of the film thickness after the formation of the barrier layer, the color conversion layer was uniformly formed in the portion without the adhesion preventing layer (on the planarization layer), and the film thickness was 300 nm. On the other hand, the film thickness of the color conversion layer on the adhesion preventing layer was about 40 nm, and it was not thick enough to function as a color conversion layer. Therefore, the color conversion layer was formed along the pattern shape formed using the adhesion preventing layer.

<Example 3>
A multicolor light emitting device was produced in the same manner as in Example 1 except that the method for forming the adhesion preventing layer was changed as follows.

"Anti-adhesion layer"
A photosensitive polysilazane having F in the main chain was used, and a pattern having a pattern width of 120 μm and a pattern pitch of 168 μm was formed on the planarizing layer. The film thickness of the adhesion preventing layer was 1 μm.
After applying to a predetermined film thickness by spin coating, pre-baking at 90 ° C. for 120 seconds, and then transferring the pattern of the photomask by applying a light of 40 mJ / cm ^{2 at} 405 nm using an exposure machine using a high-pressure mercury lamp as a light source Then, development was performed using a developer containing TMAH as a main component. Thereafter, post-baking was performed at 120 ° C. for 600 seconds for curing.

The composition ratio of the surface of the adhesion preventing layer was analyzed by ESCA. The detection ratio of F was about 5% with respect to the detected amount of C.
From the measurement of the film thickness after the formation of the barrier layer, the color conversion layer was uniformly formed in the portion without the adhesion preventing layer (on the planarization layer), and the film thickness was 300 nm. On the other hand, the film thickness of the color conversion layer on the adhesion preventing layer was about 20 nm, and it was not thick enough to function as a color conversion layer. Therefore, the color conversion layer was formed along the pattern shape formed using the adhesion preventing layer.

<Example 4>
A multicolor light emitting device was produced in the same manner as in Example 1 except that the method for forming the color conversion layer was changed as follows.

"Color conversion layer"
A color conversion layer made of Alq3 and DCM-2 was prepared using a resistance heating vapor deposition apparatus with an ultrasonic vibrator (manufactured by Honda Electronics Co., Ltd., HM2412) attached to a substrate support jig. A color conversion film having a film thickness of 300 nm was produced by co-evaporation in which Alq3 and DCM-2 were heated in separate crucibles in the vapor deposition apparatus. At this time, the heating temperature of each crucible was controlled so that the deposition rate of Alq3 was 0.3 nm / s and the deposition rate of DCM-2 was 0.005 nm / s. The color conversion layer of this example contained 2 mol% DCM-2 based on the total number of constituent molecules of the color conversion layer (Alq3: DCM-2 molar ratio is 49: 1).
The ultrasonic vibrator was vibrated for 10 seconds at the start of vapor deposition and every 100 seconds during vapor deposition. The number of vibrations during the deposition was 11 times.

  From the measurement of the film thickness after the formation of the barrier layer, the color conversion layer was uniformly formed in the portion without the adhesion preventing layer (on the planarization layer), and the film thickness was 300 nm. On the other hand, the film thickness of the color conversion layer on the adhesion preventing layer was about 5 nm, and it was not a thickness that could function as a color conversion layer. Therefore, the color conversion layer was formed along the pattern shape formed using the adhesion preventing layer.

<Example 5>
A multicolor light emitting device was produced in the same manner as in Example 1 except that the method for forming the color conversion layer was changed as follows.

"Color conversion layer"
An N ₂ gun was prepared in a glove box connected to a resistance heating vapor deposition apparatus. The supply pressure of N ₂ was set to 0.2 MPa, and the substrate was fixed to a support jig for the substrate on which the color conversion layer was formed. N ₂ swings gun hand along the formation direction of the pattern in the vertical direction to remove the color conversion layer formed on the antiadhesive layer.
From the film thickness measurement after the formation of the barrier layer, the color conversion layer on the adhesion preventing layer is almost removed, and the color conversion layer is uniformly formed on the portion without the adhesion preventing layer (on the planarization layer). The film thickness was 300 nm. Therefore, the color conversion layer was formed along the pattern shape formed using the adhesion preventing layer.

<Example 6>
A multicolor light emitting device was produced in the same manner as in Example 1 except that the method for forming the color conversion layer was changed as follows.

"Color conversion layer"
An adhesive tape (No. 5080, manufactured by Sumitomo 3M) was prepared in a glove box connected to a resistance heating vapor deposition apparatus. It fixed to the support jig of the board | substrate with which the color conversion layer was formed, and the adhesive tape was set | placed on the board | substrate. Thereafter, the glass substrate was placed on the adhesive tape, and a roller having a weight of 2 kg was reciprocated once on the glass substrate, and then the glass substrate and the adhesive tape were removed.
From the film thickness measurement after the formation of the barrier layer, the color conversion layer on the adhesion prevention layer is almost removed, and the color conversion layer is uniformly formed on the portion without the adhesion prevention layer (on the planarization layer), The film thickness was 300 nm. Therefore, the color conversion layer was formed along the pattern shape formed using the adhesion preventing layer.

<Comparative Example 1>
A multicolor light emitting device was produced in the same manner as in Example 1 except that the adhesion preventing layer was not formed. From the film thickness measurement after barrier layer formation, the film thickness of the color conversion layer was 300 nm.

<Comparative example 2>
A multicolor light emitting device was produced in the same manner as in Example 1 except that the adhesion preventing layer was not formed and the color conversion layer was formed using a metal mask.
That is, a metal mask having an opening in the red region of a metal mask having an outer shape of 210 mm × 210 mm, a material of Invar, and an opening size of 158 × 46 μm was manufactured.
The processing accuracy of the metal mask was 15 μm for the long dimension (between alignment markers) and 2 μm for the short dimension.

  First, the metal mask and the glass substrate were aligned with a resistance heating vapor deposition apparatus, and the alignment accuracy on the image recognition apparatus was set to ± 1 μm. Thereafter, a color conversion film having a film thickness of 300 nm was produced by co-evaporation in which Alq3 and DCM-2 were heated in separate crucibles in the vapor deposition apparatus. At this time, the heating temperature of each crucible was controlled so that the deposition rate of Alq3 was 0.3 nm / s and the deposition rate of DCM-2 was 0.005 nm / s. The color conversion layer of this example contains 2 mol% of DCM-2 based on the total number of constituent molecules of the color conversion layer (the molar ratio of Alq3: DCM-2 is 49: 1).

From the film thickness measurement after the barrier layer was formed, the film thickness of the color conversion layer in the red region was 300 nm, and the film thickness of the color conversion layer in the blue and green regions was 0 nm.
However, the alignment accuracy of the red region is low, and the ratio of the color conversion layer laminated on the red region is 70 to 80% when the adhesion preventing layer is used.
The red conversion efficiency of this panel was 70 to 80% when the adhesion preventing layer was used.

As described above, by forming the adhesion preventing layer on the planarizing film, it is possible to reduce the adhesion rate of the color conversion material to the planarizing layer, which is difficult to realize when a metal mask is used. A panel with a resolution of 150 ppi could be produced.
In particular, adhesion of the color conversion material to the flattening layer can be further reduced by applying ultrasonic vibration during vapor deposition of the color conversion layer, blowing an inert gas, and removing with an adhesive tape.

  According to the present invention, the color conversion layer can be selectively formed finely, and a high-definition panel can be manufactured.

It is a figure which shows one embodiment of the multicolor light-emitting device manufactured by the manufacturing method of the multicolor light-emitting device of this invention. It is a manufacturing process flowchart of a multicolor light emitting device.

Explanation of symbols

1 2nd electrode (cathode) 2 1st electrode (transparent electrode)
DESCRIPTION OF SYMBOLS 3 Organic light-emitting body 4 Barrier layer 5 Flattening layer 6 Adhesion prevention layer 10 Transparent support substrate 20R Red conversion layer 30R Red color filter 30G Green color filter 30B Blue color filter 40 Black matrix

Claims (6)

A color filter forming step of forming a color filter formed by independently disposing two or more types of filters that transmit light of different wavelength ranges on a transparent substrate;
A flattening layer forming step of forming a flattening layer on the upper surface of the color filter formed in the color filter forming step;
An adhesion preventing layer forming step of forming a layer having a desired pattern on the upper surface of the planarizing layer formed in the planarizing layer forming step, which has a low affinity for the color conversion layer and functions as an adhesion preventing layer;
A color conversion layer that absorbs light of a certain wavelength and outputs light having a wavelength different from the absorbed wavelength is formed on the planarization layer and an adhesion preventing layer formed in a desired pattern on the flattening layer by an evaporation method. And a color conversion layer forming step for producing a multicolor light emitting device.   The method for producing a multicolor light emitting device according to claim 1, wherein the adhesion preventing layer is made of a polymer material having an OH group in the main chain and / or side chain.   The method for producing a multicolor light emitting device according to claim 1, wherein the adhesion preventing layer is made of a polymer material having F in the main chain and / or side chain.   The color conversion layer forming step includes a step of removing the color conversion layer deposited on the adhesion preventing layer by vibrating the transparent substrate continuously or intermittently. The manufacturing method of the multicolor light-emitting device of any one of these.   The said color conversion layer formation process has the process of removing the color conversion layer deposited on the adhesion prevention layer by spraying inert gas, The any one of Claims 1-3 characterized by the above-mentioned. A method for manufacturing a multicolor light emitting device.   The said color conversion layer formation process has the process of removing the color conversion layer deposited on the adhesion prevention layer using an adhesive tape or an adhesive roller, The any one of Claims 1-3 characterized by the above-mentioned. The manufacturing method of the multicolor light-emitting device of description.

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