KR20120121834A - Method of manufacturing organic electroluminescence display device - Google Patents

Abstract

PURPOSE: A method for manufacturing an organic electroluminescence(EL) display device is provided to obtain an organic EL device having equivalent device characteristics of an organic EL device which is formed by a vacuum in-situ method. CONSTITUTION: Organic compound layers(22a,22b,22c) are formed on first electrodes(21a,2lb,21c). A peeling layer(30) is formed on the organic compound layer. The organic compound layer is removed from the peeling layer. The peeling layer includes a deposition film consisting of the organic compound. A polar solvent includes water and a solvent which is mixed with the polar solvent.

Description

Manufacturing method of organic electroluminescent display device {METHOD OF MANUFACTURING ORGANIC ELECTROLUMINESCENCE DISPLAY DEVICE}

TECHNICAL FIELD This invention relates to the manufacturing method of an organic electroluminescent (EL) display apparatus.

BACKGROUND ART A display device equipped with a generally known organic EL element is a device in which pixels having a single or multiple organic EL elements are arranged in a predetermined pattern. By these pixels, the display area of the display device is finely divided two-dimensionally. The organic EL element contained in these pixels is an electronic element which outputs any one of red light, green light, and blue light, for example. A display device equipped with an organic EL element obtains a full color image by driving an organic EL element that outputs a desired color at a desired emission intensity.

By the way, in the organic EL element which is a component of the display device, the organic compound layer in the element is a thin film layer formed by forming a thin film made of an organic material by vapor deposition or the like. When forming the organic compound layer in the organic EL element of the display device for each element by vapor deposition, fine patterning technique is required. When performing the patterning, a fine metal mask according to the fineness of the patterning is required. However, the vapor deposition film deposited when the metal mask is used for repeated vapor deposition may narrow the opening of the mask, or the stress may deform the opening of the mask. Therefore, it is necessary to wash the mask used after a certain number of film formation, which is a disadvantage in terms of manufacturing cost. Further, in part due to the limitation of the processing accuracy of the mask, the pixel size is limited to about 100 μm, which is disadvantageous for the finer size. Further, regarding the substrate size, when the high-definition metal mask is enlarged, it is necessary to increase the rigidity of the frame of the mask in order to secure the positional accuracy of the opening of the mask. However, increasing the rigidity of the mask causes an increase in the weight of the mask itself. For this reason, from the viewpoint of processability and handling, when manufacturing a large-sized display device after the fourth generation or later, an optimal manufacturing process of a high-definition organic EL element and a display device on which the organic EL element is mounted is present. Not embodied in

Under these circumstances, a method of manufacturing a display device having a high-definition organic EL element by a method without using a metal mask has been proposed.

In the method proposed in Japanese Patent No. 3839276, a photoresist is directly formed on the light emitting layer. When employing this method, the photoresist used generally contains many photoinitiators, crosslinking agents and the like. Here, photoinitiator, crosslinking agent, etc. are materials for changing insolubility to a developing solution at least, respectively. In the method proposed in Japanese Patent No. 4507759, an intermediate layer formed of a water-soluble material is provided on the organic compound layer, and the organic compound layer is patterned by performing photolithography on the intermediate layer. Here, the water-soluble polymer constituting the intermediate layer to be formed on the light emitting layer is generally insulating. In addition, Japanese Patent No. 4548211 has proposed a technique of using a water-soluble polymer as a release layer to peel a photoresist together with the release layer.

The resist, the intermediate layer, the release layer and the like are generally insulating. As a result, if any one of these layers is left on the surface of the light emitting layer or the like of the organic EL element, the layer becomes a resistance, and the device characteristics of the organic EL element in the organic EL display device deteriorate remarkably. Accordingly, it is necessary to remove the resist, the intermediate layer, the release layer, and the like so as not to remain on the surface of the light emitting layer or the like. However, it is difficult to completely remove the resist, the intermediate layer, the release layer, and the like, each formed of a polymer material, so that a residue which cannot be completely removed remains in the apparatus to some extent. For example, the following is a concern about deterioration of device characteristics. Trace impurities contained in the resist, the intermediate layer, the exfoliation layer, or the like, or a solvent used when applying the resist, the intermediate layer, the exfoliation layer, or the like diffuses to the light-emitting layer constituting the organic compound layer and causes crystallization of the organic compound layer. Becomes Accordingly, the following problem has arisen in the prior art. The device characteristics of the organic EL element included in the organic EL display device manufactured by patterning including the use of a photolithography process are determined by the organic EL element formed like a pattern such as a metal mask in a vacuum in-situ method. It is worse than device characteristics.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide device characteristics equivalent to those of an organic EL element formed by a vacuum in-situ method using a metal mask or the like while using a patterning method based on photolithography. The present invention provides a method for manufacturing an organic EL display device having an organic EL element.

A method for manufacturing an organic EL display device of the present invention includes an organic EL having an organic EL element composed of a first electrode and a second electrode and an organic compound layer disposed and patterned between the first electrode and the second electrode. A method of manufacturing a display device, comprising: forming an organic compound layer forming at least the organic compound layer on the first electrode; A step of forming a release layer for forming a release layer on the organic compound layer; A first processing step of the release layer for patterning the release layer; A processing step of the organic compound layer for removing the organic compound layer in a region not covered with the release layer processed in the first processing step of the release layer; And a second processing step of the release layer for removing a part of the release layer, wherein the release layer includes a vapor deposition film made of a charge-transporting organic compound and is soluble in a polar solvent.

According to the present invention, an organic EL display comprising an organic EL element formed by a vacuum in-situ method and an organic EL element having a device characteristic equivalent to those using a metal mask or the like while using a patterning method based on photolithography. It is possible to provide a method of manufacturing the device.

Further features of the present invention will become apparent from the description of exemplary embodiments below with reference to the accompanying drawings.

1 is a schematic cross-sectional view showing an example of an organic EL display device manufactured by the manufacturing method of the present invention.
2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 2i, 2j, 2k, 2l, 2m, 2n, and 2o respectively show Example 1 in the method for manufacturing the organic EL display device of the present invention. It is a cross-sectional schematic diagram shown.
3 is a graph showing a change in thickness with respect to etching time in Compound 1 and Compound A2.
4 is a graph showing the solubility of an IPA / water mixed solvent (polar solvent) between a condensed polycyclic hydrocarbon compound (Compound 1) and a heterocyclic compound (Compound A2).
5A, 5B, 5C, 5D, and 5E are cross-sectional schematic diagrams showing Example 2 of the method for manufacturing the organic EL display device of the present invention, respectively.
6A, 6B, 6C, 6D, 6E, and 6F are cross-sectional schematic diagrams showing Example 3 of the method for manufacturing the organic EL display device of the present invention, respectively.
7 is a block diagram illustrating an example of a digital camera system.

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

The method according to the present invention has an organic EL element comprising a first electrode and a second electrode and an organic compound layer disposed between the first electrode and the second electrode, wherein the organic compound layer has a desired shape. It is a manufacturing method of the patterned organic EL display apparatus.

The manufacturing method of this invention includes the process (A)-(E) shown below: (A) Formation process of the organic compound layer which forms an organic compound layer on a 1st electrode; (B) forming a release layer for forming a release layer on the organic compound layer; (C) the first processing step of the release layer for processing the release layer into a desired shape; (D) The process of the organic compound layer which removes the organic compound layer of the area | region which is not covered by the peeling layer processed by the 1st process process of the said peeling layer; (E) 2nd process of peeling layer which removes a part of said peeling layer.

In addition, in this invention, a peeling layer is a vapor deposition film which consists of a charge transport organic compound, and is a thin film layer soluble in a polar solvent. In general, the organic compound layer of the organic EL element is formed of a compound having a low solubility in a polar solvent. Therefore, in the said process (E), a peeling layer can be selectively melt | dissolved selectively, hardly dissolving an organic compound layer. Furthermore, the peeling layer which remains on the surface of an organic compound layer after the said process (E) is a layer formed from the charge-transporting organic compound. Thus, even if a layer constituting an organic EL element such as a second electrode is formed thereon, the flow of charges is not disturbed. At this time, it is preferable that the method of this invention further includes the process of forming the layer containing an alkali metal after the said process (E) (2nd process process of a peeling layer).

(Example 1)

Hereinafter, embodiments of the present invention will be described with reference to the drawings. At this time, in the following description, the well-known technique or well-known technique of the said technical field can be applied especially about the part which is shown in a figure, or a part without description. In addition, the Example described below is only one Example of this invention to the last, and this invention is not limited to these. As long as the combination does not deviate from the gist of the present invention, the embodiments described below may be appropriately combined.

(Organic EL display device)

1 is a schematic cross-sectional view showing an example of an organic EL display device manufactured by the manufacturing method of the present invention. In the organic EL display device 1 of FIG. 1, three types of subpixels, that is, the first subpixel 20a, the second subpixel 20b, and the third subpixel (on the support substrate 10) are provided. 20c) is installed. Here, the pixel is composed of the first subpixel 20a, the second subpixel 20b, and the third subpixel 20c. In the organic EL display device 1 of FIG. 1, one pixel composed of the first subpixel 20a, the second subpixel 20b, and the third subpixel 20c is shown, but the actual organic EL display is shown. In the apparatus, a plurality of pixels are arranged in a matrix on the support substrate 10.

In the organic EL display device 1 of FIG. 1, each of the subpixels 20a, 20b, or 20c includes the first electrode 21, the organic compound layer 22, the charge transport layer 23, and the charge. The injection / transport layer 24 and the second electrode 25 are provided.

The first electrodes 21 (21a, 2lb or 21c) are electrode layers (lower electrodes) provided on the support substrate 10, and are provided individually for each subpixel. The first electrodes 21a, 2lb, and 21c are electrically connected to switching elements (not shown) such as transistors, respectively.

The organic compound layer 22 (22a, 22b, or 22c) is a single layer which consists of a predetermined organic compound, or a laminated body formed from these multiple layers. At this time, the organic compound layer 22a, 22b, or 22c has a light emitting layer (not shown) for outputting at least one of colors including red, green, and blue.

The charge transport layers 23 (23a, 23b or 23c) are provided to inject or transport holes or electrons injected from the second electrode 25 into the organic compound layer 22. In the organic EL display device 1 of FIG. 1, the charge transport layers 23a, 23b or 23c are provided separately for each subpixel.

The charge injection / transport layer 24 is provided along with the charge transport layer 23 to inject or transport the holes or electrons injected from the second electrode 25 to the organic compound layer 22. In the organic EL display device 1 of FIG. 1, the charge injection / transport layer 24 is provided as a layer common to the subpixels 20a, 20b, and 20c, respectively, but the present invention is not limited thereto. That is, the charge injection / transport layer 24 may be provided separately for each subpixel.

In the organic EL display device 1 of FIG. 1, the second electrode 25 (upper electrode) is provided as a layer common to each of the subpixels 20a, 20b, 20c like the charge injection / transport layer 24. However, the present invention is not limited to this. That is, the second electrode 25 may be provided separately for each subpixel.

(Method of manufacturing organic EL display device)

Next, as a specific example of the manufacturing method of the organic EL display device of FIG. 1 according to the present invention, a manufacturing method of the organic EL display device having three types of subpixels displaying different colors will be described.

As described above, the method for manufacturing the organic EL display device of the present invention includes at least the following steps (A) to (E): (A) Step of forming an organic compound layer for forming an organic compound layer on the first electrode ; (B) forming a release layer for forming a release layer on the organic compound layer; (C) the first processing step of the release layer for processing the release layer into a desired shape; (D) The process of the organic compound layer which removes the organic compound layer of the area | region which is not covered by the peeling layer processed by the 1st process process of the said peeling layer; (E) 2nd process of peeling layer which removes a part of said peeling layer.

2A to 2O are cross-sectional schematic diagrams each showing an example of a manufacturing process of the organic EL display device of FIG. 1. 2A to 2O are schematic cross-sectional views showing Example 1 of the method for manufacturing the organic EL display device of the present invention, respectively. When manufacturing the organic EL display device of FIG. 1, for example, an organic EL display device is manufactured by the following steps: (1) Formation process of first electrode (FIG. 2A); (2) formation process of organic compound layer (FIG. 2B); (3) formation process of peeling layer (FIG. 2C); (4) formation process of photosensitive resin layer (FIG. 2D); (5) processing step of photosensitive resin layer (FIG. 2E); (6) 1st process process of peeling layer (FIG. 2F); (7) processing step of organic compound layer (FIG. 2G); (8) removal process of photosensitive resin layer (FIG. 2L); (9) 2nd processing process (formation process of charge transport layer) of peeling layer (FIG. 2m); (10) formation process of charge injection / transport layer (FIG. 2N); And (11) a step of forming the second electrode (FIG. 2O).

However, the process of said (1)-(11) is a specific example to the last, and this invention is not limited to this form. Since the organic EL display device 1 of FIG. 1 needs to manufacture three types of subpixels 20a, 20b, and 20c, each having a different emission color, the organic EL display device 1 of FIG. Before performing a process, it is necessary to perform the process of (2)-(7) three times in total. For example, first, the organic compound layer 22a in the first subpixel 20a is formed by the steps (2) to (7) (Fig. 2G). And the organic compound layer 22b in the 2nd subpixel 20b is formed by the process of (2)-(7) (FIG. 2H-FIG. 2I). Then, the organic compound layer 22c in the 3rd subpixel 20c is formed by the process of (2)-(7) (FIG. 2J-FIG. 2K).

Next, each process of said (1)-(11) is demonstrated concretely.

(Step of Forming First Electrode)

First, first electrodes 21a, 2lb, and 21c are formed on the support substrate 10. As the support substrate 10, a well-known board | substrate, such as a glass substrate, can be selected. The first electrodes 21a, 2lb, and 21c are electrode layers made of known electrode materials, respectively, and appropriately select its constituent materials in accordance with the light extraction direction. In the case of manufacturing a top emission organic EL display device, the first electrodes 21a, 2lb, and 21c are reflective electrodes, and the second electrode 25 described later is a light transmissive electrode. On the other hand, in the case of manufacturing a bottom emission type organic EL display device, the first electrodes 21a, 2lb, and 21c are light transmissive electrodes and the second electrode 25 is a reflective electrode.

When the first electrodes 21a, 2lb, 21c are formed as reflective electrodes, the constituent material of each of the first electrodes 21a, 2lb, 21c is preferably a metal such as Cr, Al, Ag, Au, or Pat. Material Of these metal materials, materials having high reflectance are more preferable because they can further improve light extraction efficiency. The reflective electrode is formed separately for each subpixel by forming a thin film of the metal material by a known method such as sputtering and processing the thin film into a desired shape by photolithography or the like. At this time, a layer made of an oxide semiconductor having light transmittance such as ITO or IOX may be further provided on the thin film made of any of the above metal materials for reasons such as protection of the thin film or adjustment of the work function. In addition, when forming the 1st electrode 21a, 2lb, 21c, vapor deposition using a metal mask may be used. Even when vapor deposition is performed using a metal mask, the first electrodes 21a, 2lb, or 21c are formed separately for each subpixel.

When the first electrodes 21a, 2lb and 21c are formed as the light transmissive electrodes, examples of the constituent material of each of the first electrodes 21a, 2lb and 21c include light such as indium tin oxide (ITO) and indium zinc oxide. There is an oxide semiconductor having permeability.

(Formation process of organic compound layer)

The organic compound layers 22 (22a, 22b or 22c) are constituent members of the organic EL display device, and are at least a single layer or a plurality of layers including a light emitting layer. Layers other than the light emitting layer in the organic compound layer 22 are, for example, a hole injection layer, a hole transport layer, an electron block layer, a hole block layer, an electron transport layer, or an electron injection layer, unless the present invention is limited thereto. The layer in contact with the light emitting layer may be a charge transport layer (hole transport layer or electron transport layer) or a charge block layer (electron block layer or hole block layer).

In addition, about the specific structure of the organic compound layer 22 with respect to the 1st electrode 21, what is necessary is just to set suitably according to the kind of carrier which the 1st electrode 21 injects toward the organic compound layer 22. FIG. That is, when holes are injected from the first electrode 21, a layer (hole injection layer or hole transport layer) for injecting or transporting holes is provided on the side of the first electrode 21, while the second electrode 25 is provided. On the side, a layer (electron injection layer or electron transport layer) for injecting or transporting electrons is provided. On the other hand, when electrons are injected from the first electrode 21, a layer (electron injection layer or electron transport layer) for injecting or transporting electrons is provided on the first electrode 21 side, while the second electrode 25 is provided. On the side, a layer (hole injection layer or hole transport layer) for injecting or transporting holes is provided.

At this time, it is preferable that the organic compound layer 22 is an amorphous film from a viewpoint of luminous efficiency. In addition, it is preferable to appropriately design the thickness of each organic layer in accordance with the light emission wavelength so as to obtain the optical interference effect.

When the hole injection layer, the hole transport layer, or both are provided, the hole injection / transport material, which is a constituent material of the hole injection layer or the hole transport layer, is not particularly limited, but at least the work function is smaller than the constituent material of the light emitting layer, and the hole transportability is provided. It is preferable to use this high material. The hole injection layer or the hole transport layer may be provided with not only a function of transporting holes but also a function of blocking electrons flowing from the light emitting layer. Alternatively, apart from the hole injection layer or the hole transport layer, a layer (electron block layer) having a function of blocking electrons flowing from the light emitting layer may be inserted between the hole transport layer (or the hole injection layer) and the light emitting layer.

As the organic light emitting material of each color (red / green / blue) in the light emitting layer, for example, an arylamine derivative, stilbene derivative, polyarylene, a condensed polycyclic hydrocarbon compound, a heterocyclic aromatic compound, a heterocyclic condensed polycyclic compound, An organometallic complex compound and the like and a homo oligomer or a hetero oligomer can be used, respectively, and the light emitting material in the present invention is not limited to the above materials.

At this time, when the organic EL display device of FIG. 1 is manufactured, the light emission colors of the light emitting layers in the three types of organic compound layers 22a, 22b and 22c respectively provided on the lower electrodes 21a, 2lb and 21c are blue, Red and green, that is, their emission colors are different from each other. In addition, the combination of emission colors is not specifically limited.

The constituent material of the hole block layer is not particularly limited as long as it has an energy barrier for preventing holes from leaking from the light emitting layer toward the cathode and has electron transport properties.

In this invention, it is necessary to selectively etch a peeling layer in the removal process of the peeling layer performed after patterning of an organic compound layer. In consideration of the above, it is preferable that the whole of the organic compound layer 22 formed in the formation process of an organic compound layer is a layer which consists of a material with low solubility in a polar solvent rather than a peeling layer. Here, the organic compound layer 22 has at least a light emitting layer, and is further selected from a hole block layer, an electron block layer, a charge transport layer (hole transport layer or electron transport layer) and a charge injection layer (electron injection layer or hole injection layer). It may include. Here, the material with low solubility in a polar solvent is specifically a condensed polycyclic hydrocarbon compound without any m-terphenyl group.

Here, the condensed polycyclic hydrocarbon compound is a cyclic unsaturated organic compound composed only of hydrocarbons. More specifically, this compound is a compound containing the condensed ring obtained by condensation of at least one side of aromatic rings, such as a benzene ring. Specific examples of the condensed polycyclic hydrocarbon compound include naphthalene, fluorene, fluoranthene, chrysene, anthracene, tetracene, phenanthrene, pyrene, triphenylene.

However, since said condensation polycyclic hydrocarbon compound is low in thermal stability as it is, it is difficult to use it as a constituent material of an organic compound layer. Therefore, the compound to which the substituent was added to these condensed polycyclic hydrocarbon compounds is used as a structural material of an organic compound layer.

Here, especially the compound which is a structural material of the uppermost layer of an organic compound layer, Preferably, the said condensed polycyclic hydrocarbon compound is an organic compound obtained by combining two or more by single bond. This organic compound contains the compound obtained by the alkyl group, such as a methyl group and an ethyl group, being suitably substituted by the condensed polycyclic hydrocarbon compound which is a main skeleton. Since such an organic compound does not contain any compound having a hetero atom (N, O, etc.) in its main chain or substituent, solubility in a polar solvent is particularly low.

The layer made of the aromatic hydrocarbon compound has charge transport properties. Here, "charge transport property" means the characteristic which can flow an electric current. Specifically, not only an electron transport layer and a hole transport layer, but also an electron injection layer, a hole injection layer, a block layer, etc. are contained in the layer which has charge transport property.

At this time, as a method of forming the layer made of the aromatic hydrocarbon compound, it is possible to use conventional methods such as vacuum deposition, spin coating, dip coating or inkjet. In consideration of the light emission characteristics of the organic EL display device, the deposition method is more preferably a vacuum deposition method.

(Formation Process of Peeling Layer)

The peeling layer 30 provided on the organic compound layer 22 may be a single layer, or may be a laminate composed of a plurality of layers. In this invention, when the peeling layer 30 consists of a single layer, this layer is a vapor deposition film formed from the material soluble in a polar solvent. Or when the peeling layer 30 is a laminated body which consists of a some layer, at least the lowest layer among the layers which comprise this laminated body is a layer which consists of low molecular weight materials formed into a film by the vacuum deposition method. More specifically, the lowermost layer of the release layer 30 is a vapor deposition film formed of a material soluble in a polar solvent. Thereby, it becomes possible to selectively remove the peeling layer 30 by using a polar solvent. In addition, in this invention, it is preferable that the peeling layer 30 is an amorphous film.

Here, the reason why the release layer 30 (or at least its lowest layer) is a vapor deposition film in which the material available for the polar solvent is formed by vacuum deposition will be described.

Since the vacuum evaporation method is a thin film formation method applied to a compound having high sublimability, the material formed by the vacuum evaporation method is limited to a low molecular weight compound which has sublimation by itself. The compound with high sublimability is a compound specifically sublimated at the temperature of 400 degrees C or less under the pressure of 10 <^-4> Pa <10> ^-5 Pa. Moreover, since the molecular weight of the compound contained in a vapor deposition film is small compared with a polymeric material, the interaction (molecular force) of the molecules which comprise a vapor deposition film is weak, and the adsorption power to the organic compound layer 22 is also weak. Furthermore, the state of the molecule | numerator in the vapor deposition film formed in amorphous state, for example, the orientation of molecules is random. For this reason, compared with a solid state and a crystalline state, intermolecular distance becomes large and it is established in the state which a molecule expands and a solvent molecule easily enters, ie, a state in which a molecule is easy to melt | dissolve. Therefore, the vapor-deposited film (of organic compound) formed by such a vacuum deposition method is etched almost uniformly from the surface by contacting a solvent containing a polar solvent, so that a desired thickness of several nm to several tens of nanometers can be left.

On the other hand, when the peeling layer is a polymer material, it is difficult to remove the peeling layer while leaving a desired thickness of several nm to several tens of nm. For example, when a conductive water-soluble polymer is used for the release layer, since the deterioration layer having low solubility can be formed in the interface region by baking drying after application, it is difficult to etch the release layer uniformly. Further, π-conjugated polymers that can be used in the light emitting layer and the like cannot be formed as a release layer because, when the material is applied, the solvent of the coating liquid causes dissolution of the organic compound layer having a lower layer.

In the 2nd process of the peeling layer mentioned later, it is preferable to use the polar solvent used in order to remove a part of peeling layer. Moreover, it is more preferable that the polar solvent used in order to remove a part of peeling layer is a mixed solvent obtained by mixing water and the organic solvent miscible with water. Two or more types of organic solvents miscible with water may be used.

Here, examples of the polar solvent include alcohols, polyhydric alcohols, ketones, esters, pyridines and ethers, except that in the second processing step of the peeling layer described later after the second processing step is performed. It is necessary to volatilize and remove the used solvent. Accordingly, the boiling point of the organic solvent to be used is preferably at least lower than the decomposition temperature or the glass transition temperature of the organic compound in the organic compound layer 22. When the alcohols are described as specific examples, alcohols each having a low carbon number, for example, methanol, ethanol, and isopropyl alcohol, are preferable because of their low boiling point.

As a factor which produces the difference between the etching rates of the film | membrane which consists of various compounds with respect to a polar solvent, ie, a difference in solubility, it can think as follows.

Compounds listed as polar solvents necessarily contain heteroatoms in the molecule, and these heteroatoms serve as polar regions of the compound molecules to be targeted. This polar portion interacts with the polar portion contained in the constituent material of the release layer, and the constituent material of the release layer is dissolved in the polar solvent. In addition, the interaction between these polar regions affects the solubility of various compounds in the polar solvent. In view of the above, it is possible to increase the solubility of the lowermost layer of the release layer than the solubility of the organic compound layer in the solvent composed of the polar solvent by appropriately selecting the polar solvent while considering the structure of the compound used as the constituent material of the release layer 30. Do.

Therefore, the material of the release layer 30 is appropriately selected in consideration of the boiling point of the polar solvent and the interaction between the polar portion contained in the compound which is the constituent material of the release layer 30 and the polar portion of the solvent molecule. This makes it possible to selectively dissolve the release layer 30.

By the way, the compound which melt | dissolves in the said polar solvent is a heterocyclic compound and the organic compound which has an electron donating or an electron withdrawing substituent specifically ,.

(1) a heterocyclic compound having charge transport properties

In the present invention, a heterocyclic compound may be used as a constituent material of the release layer 30. In the present invention, a heterocyclic compound having excellent charge transport properties is suitably used. Examples include heterocyclic compounds such as pyridine, bipyridine, triazine, phenanthroline, quinoline, imidazole, oxazole, thiazole, oxadiazole and thiadiazole, respectively, as basic skeletons. Compound group. At this time, when such a compound contains quinoline as a basic skeleton, the compound may be a quinolinate complex. The compound contained in the compound group of this heterocyclic compound has the following compound, for example.

(2) group of compounds having m-terphenyl group and condensation ventilation, respectively

In this invention, you may use the compound which has m-terphenyl group and condensation ventilation as a constituent material of the peeling layer 30. The presence of the m-terphenyl group improves the solubility in the polar solvent, but the peeling layer needs to be improved in terms of the solubility in the polar solvent as well as thermal stability such as glass transition temperature. For this reason, it is preferable to use the compound obtained by combining the m-terphenyl group and the condensed polycyclic hydrocarbon compound as a constituent material of the peeling layer 30. Examples of the compound having condensation ventilation with this m-terphenyl group include the following compounds.

(3) Group of charge transport compounds each having electron-withdrawing groups

In the present invention, a charge transport compound having an electron withdrawing group may be used as a constituent material of the release layer 30. Here, examples of the electron withdrawing group include a ketone group and a cyano group. Examples of the compound having this electron withdrawing group include the following compounds.

One type may be used independently from the said three types of compound group, or may be used in combination of 2 or more types from a viewpoint of the improvement of the solubility with respect to a polar solvent.

In a heterocyclic compound, the charge is limited to hetero elements other than carbon (N, O or S, etc.). For example, in a pyridine having a nitrogen atom in a ring, the negative charge is localized on the nitrogen atom, and thus the polarity of the entire molecule is generated. Here, it is said that an organic solvent containing a hydrogen atom (miscible with water) that localizes a positive charge such as a hydroxyl group (-OH) is interposed. As a result, a hydrogen bond is formed between the site (N atom) of the heterocyclic compound and the localized negative charge and the hydrogen atom localized with the positive charge in the polar solvent molecule. When the hydrogen bond is formed as described above, the heterocyclic compound is easily dissolved or dissolved in the polar solvent.

Similarly, the compound which has polarity by containing at least a hetero atom (N, O, S, etc.) improves the solubility with respect to a polar solvent compared with a condensed polycyclic hydrocarbon compound.

For example, in a compound in which an electron-withdrawing group or an electron-donating group is introduced into an aromatic ring, a bias of π electrons occurs and a polarization phenomenon occurs. Here, in the case where a substituent of the electron withdrawing group is introduced, polarity is generated by localizing negative charges on the substituent. When a substituent of the electron donating group is introduced, polarity is generated by localizing a positive charge on the substituent. This polarization enables interaction with the solvent molecules of the polar solvent, so that the solubility in the organic solvent is improved.

On the other hand, the aromatic hydrocarbon compound which does not have any condensed ring, specifically, the compound in which the benzene rings are connected by a single bond, is small in size compared with the condensed polycyclic hydrocarbon compound. For this reason, the former compound improved the solubility in a polar solvent compared with a condensed polycyclic hydrocarbon compound. In particular, the molecules each having an m-terphenyl structure are difficult to crystallize because they have a structure that is difficult to orient each other. For this reason, the solubility in a polar solvent further improves.

In view of the above considerations, it is preferable to use a compound belonging to any one of the following compound groups as a material having good charge transportability and good solubility for the release layer used in the present invention. However, the material is not limited to the following examples as long as the material follows the above consideration.

Here, the difference in solubility in the polar solvent between the constituent material of the organic compound layer and the constituent material of the release layer will be described. Specific examples include the following compound 1 which is a compound having a condensed polycyclic hydrocarbon having no m-terphenyl structure used as a constituent material of the organic compound layer; And the etching rate of the following compound A2 used as a constituent material of a peeling layer is demonstrated.

In the present invention, a large etching rate means a fast dissolution rate. And a large etching rate means that the solubility in the solvent (polar solvent) of the layer which has a target material is high.

3 is a graph showing the change in thickness with respect to the etching time in Compound 1 and Compound A2. Here, FIG. 3 is a mixed solvent obtained by mixing IPA and water so that isopropyl alcohol (IPA) becomes 60 weight% as a solvent which consists of a polar solvent (henceforth a case called "IPA / water mixed solvent". The result of etching of each layer at the time of using () is shown.

As can be seen from Fig. 3, the layer (A layer) made of compound 1, which is a condensed polycyclic hydrocarbon compound having no m-terphenyl structure, hardly decreases in thickness even when the etching time is increased. On the other hand, the thickness of the layer (layer B) which consists of compound A2 which is a heterocyclic compound reduces with time. When the etching rate of each layer is calculated by making the etching conditions the same, the etching rate of the A layer is 0.008 nm / sec, while the etching rate of the B layer is 0.87 nm / sec, that is, the latter to the former ratio is about 100. .

Here, the ratio (n) of the etching rate by the polar solvent in an organic compound layer (equivalent to A layer) and a peeling layer (equivalent to B layer) can be represented as follows.

At this time, the organic compound layer described in the above formula includes, for example, a hole block layer, a light emitting layer, an electron block layer or a hole transport layer. In the present invention, n needs to be larger than at least one. n is preferably larger than 10 (n> 10). Here, when said compound 1 is used for the uppermost layer of an organic compound layer, and compound A2 is used for a peeling layer (lowest layer), n becomes about 100. Accordingly, in consideration of the solubility of each material in the polar solvent, selecting the constituent material of the uppermost layer of the organic compound layer and the constituent material of the peeling layer (lowest layer) can increase the etching rate ratio of both layers. Thereby, selective removal of the release layer is possible using a polar solvent. Therefore, the organic compound layer 22 is protected from damage due to elution to the polar solvent, penetration of the solvent, and the like. In addition, when each end of the film is exposed, at least n is 10 in each of all the layers in the organic compound layer 22 so as to prevent the end of the organic compound layer 22 from eluting with a solvent composed of a polar solvent. Satisfy a greater relationship.

The solubility of the compound which is a constituent material of each layer in the above-mentioned IPA / water mixed solvent is changed depending on the weight ratio of IPA in the mixed solvent. 4 is a graph showing the solubility of the compound 1 (condensed polycyclic hydrocarbon compound) and compound A2 (heterocyclic compound) in the IPA / water mixed solvent (polar solvent). In the graph of FIG. 4, the horizontal axis represents the weight percent concentration of IPA in the IPA / water mixed solvent, and the vertical axis represents the amount of the condensed polycyclic hydrocarbon compound or heterocyclic compound dissolved in 1 g of the solvent. As can be seen from FIG. 4, Compound 1 (condensed polycyclic hydrocarbon compound) has a dissolution amount of 5 µg in 1 g of an IPA / water mixed solvent having an IPA of 80% by weight, while Compound A2 (heterocyclic compound) has a dissolution amount of 73 µg. .

In addition, the graph of FIG. 4 is also the graph which demonstrates the following item (i) and (ii): (i) When the density | concentration of IPA in an IPA / water mixed solvent is too high, the structural material and organic compound layer of a peeling layer. All of the constituent materials of the present invention are in such a situation that the dissolution rate in the IPA / water mixed solvent is too fast and the etching rate ratio n is close to one; And (ii), in the case of item (i), by adding water to thin the concentration of IPA, the etching rate ratio n can be increased while lowering the dissolution rate of each material.

In this case, it is preferable to include water in the solvent. Specifically, it is preferable to appropriately adjust the content of water so that the etching rate of the release layer becomes larger with respect to the organic compound layer. More preferably, the content of water is appropriately adjusted so that the etching rate ratio (n) of the layer located on the uppermost layer in the organic compound layer and the peeling layer exceeds 10. As a result, the peeling layer can be removed more selectively, thereby preventing the deterioration of the characteristics of the organic EL display device.

(1st processing process of peeling layer)

In this invention, the photolithographic method can be used as a means of patterning (processing) the peeling layer 30 to a desired shape. Here, the processing process (1st processing process of a peeling layer) of the peeling layer accompanying using photolithography method is demonstrated.

(i) Formation and processing process of photosensitive resin layer

In the case of using the photolithography method, it is first necessary to provide the photosensitive resin layer 40 on the peeling layer 30. A well-known material can be used for the photosensitive resin which is a constituent material of the photosensitive resin layer 40. Moreover, as a formation method of the photosensitive resin layer 40, existing methods, such as a spin coating method, a dip coating method, or the inkjet method, can be used. In some situations, vacuum deposition may be used.

After the photosensitive resin layer 40 is formed, the photosensitive resin layer 40 is processed. Here, the processing process of the photosensitive resin layer 40 is divided into the exposure (exposure process) to the photosensitive resin layer, and the image development (developing process) of the photosensitive resin layer.

Here, in the exposure process, the existing light irradiation apparatus can be used. At this time, the exposure apparatus may be used depending on the fineness of the mask pattern. In addition, when performing this exposure process, the photomask 50 which has an opening in the area | region to expose is used. At this time, as a photomask, the photomask which has a light shielding area which consists of a Cr thin film generally used can be used. On the other hand, ultraviolet light or visible light can be used as light irradiated to the photosensitive resin layer 40 in this exposure process.

By the way, when performing an exposure process, it is preferable to consider the property of the photosensitive resin which is a constituent material of the photosensitive resin layer 40, and to determine the exposure area of the photosensitive resin layer 40. FIG. Specifically, when using positive photosensitive resin, the area | region in which the photosensitive resin layer 40 is to be removed at the next image development process is called exposure area. On the other hand, when using negative photosensitive resin, the area | region which wants to leave the photosensitive resin layer 40 at the next image development process is called exposure area. Here, FIG. 2E shows the case of using positive photosensitive resin. In FIG. 2E, the region 42 irradiated with the ultraviolet light 51 in the photosensitive resin layer 40 is removed in the next development step. On the other hand, the area | region 41 cut | disconnected from the ultraviolet light by the photomask 50 is the organic compound layer 22a provided in the predetermined | prescribed area | region (1st subpixel 20a) in the process of the peeling layer performed later, or the process of the organic compound layer. Protects).

What is necessary is just to use the developing solution suitable for the photosensitive resin which is a structural material of the photosensitive resin layer 40 when performing a image development process.

(ｉｉ) 1st process of peeling layer

Next, the peeling layer 30 is processed by selectively removing a region of the peeling layer 30 which is not covered with the photosensitive resin layer 40. Although the selective removal method of the peeling layer 30 is not specifically limited, Specifically, the existing thin film processing methods, such as a wet etching or dry etching, can be used, However, the influence of the side etching by a solvent is arbitrary. Dry etching is preferred because it is smaller than other methods.

In the above description, although the photolithography process including the thing using a photoresist is used as a processing means of the peeling layer 30, the processing method of the peeling layer 30 is not limited to this. For example, you may pattern a peeling layer to a desired shape using the inkjet system, printing, laser processing, etc. In this case, the release layer patterned into a desired shape can be formed without forming any photoresist. For this reason, it is recommended to use the peeling layer 30 as an etching mask at the time of processing an organic compound layer in a next process (processing process of an organic compound layer). At this time, when using the peeling layer 30 as an etching mask, it is preferable to make thickness of the peeling layer 30 thicker than an organic compound layer at least. In addition, since the high-definition metal mask is not used in the manufacturing method of the present invention, it is possible to achieve high fineness of setting the pixel size to about 10 m. Therefore, the manufacturing of the organic EL display device having a large support substrate size after the fifth generation can be realized.

(Process of Organic Compound Layer)

Next, the organic compound layer 22 in the area | region which is not coat | covered with the peeling layer 30 among the organic compound layer 22 is selectively removed. The processing method of the organic compound layer 22 is not specifically limited, Conventional methods, such as wet etching or dry etching, can be used, but dry etching is preferable since there is no worry about side etching by a solvent.

By the above process, an organic compound layer can be formed so that it may selectively install only a predetermined subpixel. In addition, by repeating the above-described forming process of the organic compound layer to the processing step of the organic compound layer by the number of times corresponding to the number of types of subpixels, the desired organic compound layer can be selectively formed in each subpixel only in the subpixels. have.

(2nd processing process of peeling layer)

Next, a part of the peeling layer 30 may be removed and thinned (processing the peeling layer 30 to thin shape). Specifically, the second processing step is a step of immersing the support substrate 10 in which the layers are formed up to the release layer 30 in the polar solvent mixed with water after the above-described processing step of the organic compound layer. Here, when the support substrate 10 in which the layers are formed up to the release layer 30 is immersed in the polar solvent mixed with water, the release layer 30 is gradually dissolved from the opposite side of the support substrate 10. Here, under the conditions of the etching rate below, the supporting substrate 10 in which the layers are formed up to the release layer 30 is immersed for a predetermined time. The etching rate previously determined from the amount (elution amount) of the constituent material of the release layer 30 eluted when the solvent is used for a certain period of time is immersed is used. Thereby, the peeling layer 30 can be processed to desired thickness. Each release layer 30 processed in this second processing step functions as a charge transport layer 23 (23a, 23b or 23c) (FIG. 2M). For this reason, the process of forming a charge transport layer can be simplified or abbreviate | omitted in a later process. In addition, the thickness of the peeling layer (charge transport layer 23 (23a, 23b or 23c)) after a 2nd process process can be changed suitably according to element design.

In the 2nd processing process of the said peeling layer, the mixing ratio between water and IPA is adjusted so that the etching rate of a peeling layer with respect to a polar solvent may be faster than an organic compound layer. For this reason, the edge part of the organic compound layer 22 (22a, 22b, or 22c) which arises in the unit of each subpixel after the organic compound process process becomes hard to melt | dissolve in the said solvent. Therefore, after performing the 2nd processing process of this peeling layer, when the said support substrate 10 is lifted up with a polar solvent, the peeling layer (while maintaining the shape of the organic compound layer 22 (22a, 22b or 22c) Only 30) can be processed. Further, if necessary, a charge transport layer such as an electron transport layer may be formed separately.

After performing the 2nd process of the peeling layer 30, the solvent which remains on the support substrate 10 in which the organic compound layer 22 is provided, or on the organic compound layer 22 is heated and removed, It is preferable. More preferably, the support substrate 10 is heated at about 80 ° C. under vacuum conditions. In this way, when the support substrate 10 is heated to remove the solvent, the charge injection layer or the charge transport layer can be formed in the next step while the formation is not affected by the solvent. At this time, the support substrate 10 may be vacuum heated before performing the next step. This vacuum heating also can reduce the effects of adhesion of water, oxygen, or foreign matter in the air.

(Formation process of charge injection / transport layer)

As described above, after the reprocessing of the release layer 30 (second processing step of the release layer 30), the charge injection / transport layer 24 is formed on the charge transport layer 23. At this time, it is preferable that this charge injection / transport layer 24 is formed as a layer common to each subpixel.

When the electron injection layer is formed as the charge injection / transport layer 24, the electron injection material which is a constituent material of the electron injection layer has a high work function. Examples of such materials include alkali metals, alkaline earth metals, alkali metal compounds (oxides, carbonates, or halogenated salts), alkali metal compounds (oxides, carbonates, or halogenated salts), and alkali metal or alkali metal compounds in electron transport materials. There is a material obtained by doping. Here, as an alkali metal, cesium, potassium, lithium etc. are mentioned specifically ,. Moreover, calcium, barium, etc. are mentioned specifically as alkaline earth metal.

On the other hand, in the case where the hole injection layer is formed as the charge injection / transport layer 24, as the hole injection material which is a constituent material of the hole injection layer, an organic compound having a small work function and an electron withdrawing material having a deep work function are suitably mentioned. Can be. As an example of the organic compound with a small work function, an arylamine compound and a phthalocyanine are mentioned. In addition, examples of the electron-absorbing material having a deep work function include F4-TNC, azatriphenylene compounds (PCD or hexacyano-hexaazatriphenylene, etc.), molybdenum oxide, and tungsten oxide.

(Step of Forming Second Electrode)

When manufacturing the top emission type organic EL display device, the second electrode 25 corresponding to the upper electrode is a transparent electrode made of a transparent conductive material. The transparent conductive material having light transmittance is preferably a material having high light transmittance. Examples of such materials include transparent conductive materials such as ITO, IPO, and CN; And organic conductive materials such as polyacetylene. At this time, the transflective film which formed the metal material, such as Ag or Al, into the film of about 10 nm-30 nm in thickness, may be used as the 2nd electrode 25. As shown in FIG. Here, in the case of forming a light-transmissive electrode with a transparent conductive material such as ITO, IGO or CNNO, the low-resistance characteristics required for the composition used in the electrode and the high transmittance necessary for improving the light extraction efficiency for the purpose of lowering the power consumption. The composition which satisfy | fills both with a characteristic is preferable. The thin film which becomes a light transmissive electrode can be formed by well-known methods, such as sputtering. In the case of producing a transparent conductive film having both the low resistance characteristic and the high transmittance characteristic described above, it is necessary to appropriately adjust the capacity of the film forming apparatus, the target, the pressure in the apparatus, and the output voltage at the time of film formation. At this time, the second electrode 25 is electrically connected to a switching element such as TFT (not shown).

(Drive of organic EL display device)

The organic EL display device manufactured by the manufacturing method of the present invention can be driven by applying a voltage between the first electrode 21 and the second electrode 25 of each of the subpixels 20a, 20b or 20c. have. Here, in the case of applying the voltage, for example, a power supply means (not shown) electrically connected to each electrode via a TFT is used.

(Example 2)

5A to 5E are cross-sectional schematic diagrams each showing Example 2 of the method for manufacturing the organic EL display device of the present invention. Here, Example 2 differs from Example 1 in that the protective layer 60 is formed on this peeling layer 30 after the formation process of the peeling layer 30 (FIG. 5A). The second embodiment will be described below with particular emphasis on the differences from the first embodiment.

(Formation process of a protective layer)

In the manufacturing method of this invention, after the formation process of the peeling layer 30, you may form the protective layer 60 on this peeling layer 30, as shown in FIG. 5A. Here, it is preferable that the protective layer 60 formed on the peeling layer 30 is a film | membrane insoluble in water and an organic solvent, and is a film | membrane which has moisture resistance and gas barrier property. Here, it is more preferable that the protective layer 60 has the characteristic which absorbs the light irradiated at the time of photolithography. It is preferable that the protective layer 60 formed in the manufacturing method of this invention is a thin film layer of the inorganic compound which uses silicon nitride (SiI) as a main material.

By forming the protective layer 60 on the release layer 30, however, a solvent used to form the photosensitive resin layer 40 in the next step penetrates the release layer 30 to contact the organic compound layer 22. Eliminate the possibility Therefore, when selecting the solvent of the photosensitive resin layer 40, the restriction that the solvent should not dissolve the organic compound layer 22 is eliminated, and a cheaper material can also be selected.

(Process of protective layer)

When the protective layer 60 is provided between the photosensitive resin layer 40 and the peeling layer 30, it is necessary to process the protective layer 60 before processing the peeling layer 30. have. Here, the process of the protective layer 60 specifically removes the area | region which is not covered by the photosensitive resin layer 41 (photosensitive resin which was not exposed in an exposure process) among the protective layers 60. FIG. (FIG. 5B). The method for selectively removing the protective layer 60 is not particularly limited, but known techniques such as wet etching or dry etching may be used. For example, when the constituent material of the protective layer 60 is SiN, dry etching using CF ₄ as the reaction gas can be used.

(Removal process of protective layer)

After performing the process of the protective layer 60 demonstrated above, similarly to Example 1, the peeling layer 30 and the organic compound layer 22a are processed (FIG. 5C). At this time, when the organic compound layer 22a is processed, the photosensitive resin layer 41 may be removed at the same time.

Thereafter, the steps from the formation of the organic compound layer 22b or 22c to the processing of the organic compound layer are performed in each subpixel (FIG. 5D), and then the protective layer 60 and the peeling layer 30 are removed (FIG. 5E). As in the present embodiment, in the case where the protective layer 60 is provided between the release layer 30 and the photosensitive resin layer 40, the photosensitive resin layer 40 is removed and then, during the processing of the protective layer described above. The protective layer 60 is removed by the method used (dry etching or wet etching, etc.). After removing the protective layer 60, the support substrate 10 is immersed in a polar solvent, and only the peeling layer 30 is processed, maintaining the shape of the organic compound layer 22 (22a, 22b, or 22c). After removing only a specific thickness from the surface of the peeling layer 30, similarly to Example 1, further, a charge transport layer, such as an electron transport layer, a charge injection / transport layer, a 2nd electrode, etc. are formed separately as needed.

(Example 3)

6A to 6F are cross-sectional schematic diagrams illustrating the third embodiment in the method of manufacturing an organic EL display device of the present invention. Here, the third embodiment differs from the second embodiment in that the protective layer 60 is formed of a plurality of layers (first protective layer 61 and second protective layer 62) (FIG. 6A). The third embodiment will be described below with particular emphasis on the differences from the second embodiment.

(Formation process of a protective layer)

As shown to FIG. 5A and 6A, the protective layer 60 may be a single layer, or may be a some layer. When the protective layer is a laminate composed of two layers, it is preferable that the first protective layer 61 formed first is formed of a water-soluble material. In addition, it is preferable that the second protective layer 62 formed after the first protective layer 61 is a film of an inorganic compound using a material that cannot be dissolved in water such as silicon nitride and an organic solvent as a main material.

Examples of the water-soluble material which is a constituent material of the first protective layer 61 include known water-soluble polymer materials such as polyvinyl alcohol, polyethylene glycol, polyvinyl pyrrolidone. Moreover, when forming a 1st protective layer, existing methods, such as a well-known spin coating method, the dip coating method, and the inkjet method, can be used. Here, since the organic compound layer 22 is a layer made of a material which does not dissolve in water, the organic compound layer 22 is not etched by a solvent when forming the first protective layer 61. In addition, when the thickness of the protective layer 60 is formed thick, the organic compound layer 22 dissolves in the solvent of the photosensitive resin layer 40, the thickness of the organic compound layer 22 decreases, or the light emitting material elutes. The influence of the back can be more reduced.

(Process of protective layer)

In addition, when the protective layer 60 consists of several layers, it is necessary to process about each protective layer. For example, when the protective layer 60 is a laminate obtained by laminating the first protective layer 61 made of a water-soluble polymer and the second protective layer 62 made of SiN in this order, Process the protective layer. First, with respect to the upper layer of the second protective layer, and subjected to dry etching using CF ₄ as a reaction gas (Fig. 6b), was then carried out, the dry etching using CF ₄ as the reaction gas for the lower layer of the first protective layer ( 6c).

(Removal process of protective layer)

After performing the process of the protective layer 60 demonstrated above, the organic compound layer 22a is processed like Example 2 (FIG. 6D). At this time, when the organic compound layer 22a is processed, the photosensitive resin layer 41 may be removed at the same time as shown in FIG. 6D.

Subsequently, a process from the formation of the organic compound layer 22b or 22c to the processing of the organic compound layer is performed in each subpixel (FIG. 6E) to remove the protective layer 60 and the peeling layer (FIG. 6F). As in the present embodiment, in the case where the protective layer 60 is provided between the release layer 30 and the photosensitive resin layer 40, the photosensitive resin layer 40 is removed and then the protective layer is processed. The protective layer 60 is removed by a method (such as dry etching or wet etching) used in the above.

Next, examples of the present invention will be described. However, the present invention is not limited to the examples described below. For example, the order of forming subpixels in terms of emission color is not limited to the order of "blue, green and red". For example, the structure and thickness of the organic compound layer are not limited to the information described in the examples. For example, in the case of injecting electrons from the first electrode, a stacking layer of organic compound layers may be employed in accordance with the injection. The invention also includes a combination of the examples described below. Techniques well known or known in the art apply to parts not specifically described or described in the specification.

(Electronics)

As described above, the organic EL display device is excellent in current efficiency, drive life, and fineness. Therefore, the organic EL display device of the present invention may be used as a display portion of various electronic devices. Electronic devices include portable devices such as digital cameras and portable information terminals, personal computers, televisions, and various printers.

As an example of an electronic device, a digital camera will be described. 7 is a block diagram illustrating an example of a digital camera system. The digital camera system 7 includes a photographing unit 71, a video signal processing circuit 72, a display device 73, a memory 74, a CPU 75, and an operation unit 76. The display device 73 constituting the digital camera system 7 in FIG. 7 uses an organic EL display device manufactured using the manufacturing method of the present invention.

The video photographed using the photographing unit 71 and the video information recorded in the memory 74 are signal-processed by the video signal processing circuit 72, converted into video signals, and then transmitted to the display device 73, It is displayed as an image.

The controller (not shown) attached to the digital camera system 7 of FIG. 7 is connected to the CPU 75 that controls the photographing unit 71, the memory 74, and the video signal processing circuit 72. The input signal from the operation unit 76 performs shooting, recording, reproducing, and display appropriate to the situation.

(Example 1)

The organic EL display device shown in FIG. 1 was manufactured according to the process shown in FIG.

(1) Formation process of the first electrode

By the sputtering method, aluminum alloys were formed on the support substrate 10 to form an Al films (reflective electrodes). At this time, the thickness of the Al film was 100 nm. Next, an ITO film was formed on the Al film by the sputtering method to form an ITO film. At this time, the thickness of the ITO film was 10 nm. In addition, the laminated body consisting of the said Al film and the ITO film functions as the 1st electrode 21. As shown in FIG. Next, by patterning the first electrode 21 based on the photolithography process, the first electrodes 21a, 2lb, 21c constituting the first subpixel, the second subpixel, and the third subpixel are respectively formed. Each was prepared (FIG. 2A).

(2) Formation process of blue organic compound layer

On the support substrate 10 on which the patterned first electrodes 21a, 2lb, 21c are formed, the blue organic compound layer 22a was formed by continuous film formation using the vacuum deposition method. First, the hole transport layer was formed to a thickness of 120 nm, and then a light emitting layer containing a blue light emitting material was formed to a thickness of 30 nm. Next, the condensed polycyclic hydrocarbon compound represented by following formula 1 was formed into a film, and the buffer layer was formed. At this time, the thickness of the buffer layer was 10 nm. The organic compound layer 22a (blue organic compound layer) was formed by the above (FIG. 2B).

(3) Formation process of peeling layer

Next, the phenanthroline derivative represented by following formula 2 was formed into a film by the vacuum deposition method, and the peeling layer 30 was formed. At this time, the thickness of the peeling layer 30 was 500 nm (FIG. 2C).

(4) Formation and processing process of photosensitive resin layer

Next, the photosensitive resin layer 40 was formed by depositing a positive photoresist (Avatronic Materials, product name "Ava 1500") by spin coating (FIG. 2D). At this time, the thickness of the photosensitive resin layer was 1000 nm. Next, the photosensitive resin layer was used using the photomask 50 so that the photosensitive resin layer 41 provided in the area | region of the 1st subpixel 20a may be left using an exposure apparatus (made by Canon, the mask aligner MPA600). The ultraviolet light 51 was exposed in the state which shielded 41 (FIG. 2E). At this time, the exposure time was 40s. After exposure, it developed for 1 minute using the developing solution (made by AJ Electronic Materials, the product name "312MIF" diluted to water, and making 50% of the density | concentration). The photosensitive resin layer 42 exposed to the ultraviolet light 51 was removed by this developing treatment.

(5) First process of peeling layer and process of blue organic compound layer

Next, oxygen was used as a reaction gas, and the peeling layer 30 which was not covered with the photosensitive resin layer 41 was removed and patterned under conditions of a flow rate of 20 cc, a pressure of 8 Pa, an output of 150 W, and a reaction time of 2 minutes. By doing in this way, the peeling layer 30 patterned in the area | region of the 1st subpixel 20a was formed (FIG. 2F). By dry etching under the same conditions, the blue organic compound layer 22a provided in the region other than the region of the first subpixel 20a was selectively removed. Thus, the organic compound layer 22a (blue organic compound layer) was formed in the area | region of the 1st subpixel 20a (FIG. 2G).

(6) Formation and processing process of red organic compound layer

Next, the red organic compound layer 22b was formed by continuous film formation using the vacuum deposition method. First, the hole transport layer was formed to a thickness of 200 nm, and then a light emitting layer containing a red light emitting material was formed to a thickness of 30 nm. Next, the condensed polycyclic hydrocarbon compound represented by said Formula (1) was formed into a film, and the buffer layer was formed. At this time, the thickness of the buffer layer was 10 nm. The organic compound layer 22b (red organic compound layer) was formed by the above. Next, the phenanthroline derivative of Formula (2) was formed into a film by the vacuum deposition method, and the peeling layer 30 was formed. At this time, the thickness of the peeling layer 30 was 500 nm. Next, the positive photoresist used in the step (4) was formed by spin coating to form the photosensitive resin layer 40 (FIG. 2H). At this time, the thickness of the photosensitive resin layer was 1000 nm. Next, after the photosensitive resin layer 40 is processed by the method similar to the process (4), the peeling layer 30 and the organic compound layer 22b are processed by the method similar to the process (5). By doing in this way, the organic compound layer 22b (red organic compound layer) was formed in the area | region of the 2nd subpixel 20b (FIG. 2I).

(7) Formation and processing process of green organic compound layer

Next, the green organic compound layer 22c was formed by continuous film formation using the vacuum deposition method. First, the hole transport layer was formed to a thickness of 160 nm, and then a light emitting layer containing a green light emitting material was formed to a thickness of 30 nm. Next, the condensed polycyclic hydrocarbon compound represented by Formula (1) was formed into a film and the hole block layer was formed. At this time, the thickness of the hole block layer was 10 nm. The organic compound layer 22c (green organic compound layer) was formed by the above. Next, the phenanthroline derivative of Formula (2) was formed into a film by the vacuum deposition method, and the peeling layer 30 was formed. At this time, the thickness of the peeling layer 30 was 500 nm. Next, the positive photoresist used in the step (4) was formed by spin coating to form the photosensitive resin layer 40 (FIG. 2J). At this time, the thickness of the photosensitive resin layer was 1000 nm. Next, after the photosensitive resin layer 40 is processed by the method similar to the process (4), the peeling layer 30 and the organic compound layer 22b are processed by the method similar to the process (5). In this way, the organic compound layer 22c (green organic compound layer) was formed in the region of the third subpixel 20c (FIG. 2K).

(8) Removing step of photosensitive resin layer

Subsequently, dry etching was performed under the conditions of a flow rate of 20 sccm, a pressure of 8 Pa, and an output of 150 W using oxygen as the reaction gas to remove the photosensitive resin layer 41 (FIG. 2L).

(9) 2nd process of peeling layer

Next, using the mixed solvent which mixed water and IPA so that an IPA concentration might be 60 weight%, a part of peeling layer 30 was removed and the 2nd processing process which thinned the peeling layer 30 was performed. At this time, since the etching rate of the compound (phenanthroline derivative represented by Formula (2)) constituting the release layer 30 in this example is 0.9 nm / sec, it is immersed in the mixed solvent for 530 seconds to release the release layer 30 A part of) was removed to form a thin film (FIG. 2M). As a result of this 2nd process, the thickness of the peeling layer 30 became 20 nm. Moreover, each peeling layer thinned by this 2nd process process functions as a charge transport layer (electron transport layer) 23a, 23b, or 23c. Next, it vacuum-heated at 80 degreeC, and the solvent remaining on the charge transport layer was removed.

(10) manufacturing process of second electrode

Next, the compound (compound A2) and cesium carbonate (Cs ₂ CO ₃ ) represented by Formula (2) were co-deposited to form an electron injection layer (charge injection / transport layer 24). At this time, the thickness of the electron injection layer was 20 nm (FIG. 2N).

Next, by sputtering, Ag which is a translucent conductive material was formed into a film, and the 2nd electrode was formed (FIG. 2O). At this time, the thickness of the second electrode was 16 nm.

Next, the sealing glass (not shown) was bonded to the substrate in a nitrogen atmosphere to prevent deterioration of the device. In this way, an organic EL display device was manufactured.

As a result of evaluating the organic EL display device 1 manufactured in this way, the current efficiency and the driving durability life of each of three colors, namely red, green and blue, are comparable to those of the organic EL display device manufactured by vacuum in-situ film formation. It was enough. Therefore, the organic EL display device manufactured by the manufacturing method of the present invention is excellent in light emission characteristics. At this time, with respect to the high definition, a pixel size of 12 µm was obtained, and the pixel size obtained by fine metal mask deposition was about 100 µm.

(Example 2)

An organic EL display device was manufactured in the same manner as in Example 1, except for the following. In Example 1, the following compound B1 (etch rate: 1.3 nm / sec) was used as a constituent material of the release layer 30. Moreover, at the time of removal of the peeling layer 30, the immersion time in the IPA / water mixed solvent was set to 370 second.

The resulting organic EL display device was evaluated in the same manner as in Example 1. As a result, as in Example 1, the display device showed good results in terms of current efficiency, driving life, and fineness.

(Example 3)

An organic EL display device was manufactured in the same manner as in Example 1, except for the following. In Example 1, the following compound C1 (etch rate: 1.5 nm / sec) was used as a constituent material of the release layer 30. Moreover, at the time of removal of the peeling layer 30, the immersion time in the IPA / water mixed solvent was set to 320 second.

The resulting organic EL display device was evaluated in the same manner as in Example 1. As a result, as in Example 1, the display device showed good results in terms of current efficiency, driving life, and fineness.

(Example 4)

An organic EL display device was manufactured in the same manner as in Example 1, except for the following. In Example 1, the formation process of the protective layer 60 between the formation process of the peeling layer 30 and the formation process of the photosensitive resin layer 40 which are performed at the time of processing the organic compound layer 22a, 22b, or 22c. Added. Moreover, the process of the protective layer 60 was added between the process of the photosensitive resin layer 40, and the process of the peeling layer 30. FIG. Furthermore, the removal process of the protective layer 60 was added between the removal process of the photosensitive resin layer 41, and the removal process of the peeling layer 30. FIG. Hereinafter, with reference to FIG. 5, the manufacturing process in this example is demonstrated focusing especially on the formation process of a protective layer, the process of a protective layer, and the process of removing a protective layer.

(1) Formation process of protective layer

First, by the same method as in Example 1, layers were formed on the support substrate 10 up to the release layer 30. Next, silicon nitride (SiN) was formed into a film on the peeling layer 30 by the CD method, and the protective layer 60 was formed. At this time, the thickness of the protective layer 60 was 1000 nm. Next, the photosensitive resin layer 40 was formed on the protective layer 60 by the method similar to Example 1 (FIG. 5A).

(2) Processing step of protective layer

Next, the photosensitive resin layer 40 was patterned. Subsequently, the protective layer 60 which is not covered with the photosensitive resin layer 41 under the conditions of a flow rate of 30 sccm, an output of 150 w, a pressure of 10 Pa, and a processing time of 7 minutes using the protective layer 60 as the reaction gas C ₄ is used. Removed (FIG. 5B). That is, the protective layer 60 was processed at this process so that the protective layer 60 may be provided corresponding to the area of each subpixel.

(3) Processing process of organic compound layer

Then, the process of the peeling layer 30 and the organic compound layer 22a was performed by the method similar to Example 1 (FIG. 5C). Next, the step (1) and the step (2) are performed in each of the second subpixel 20b and the third subpixel 20c, whereby the second subpixel 20b and the third subpixel 20c. The organic compound layers 22b and 22c respectively provided in FIG. 5 were formed and processed (FIG. 5D).

(4) Removing the protective layer

Next, the photosensitive resin layer 41 was removed by the method similar to Example 1. Thereafter, the protective layer 60 was removed under the conditions of a flow rate of 30 sccm, an output of 150w, a pressure of 10 Pa, and a processing time of 7 minutes by using Cf ₄ as a reaction gas. Next, a part of the peeling layer 30 was removed and thinned by the method similar to Example 1. In this way, the charge transport layers 23a, 23b, 23c were formed, respectively (FIG. 5E). Next, the charge injection / transport layer 24 and the second electrode 25 were formed in this order by the same method as in Example 1. In this way, an organic EL display device was obtained.

The resulting organic EL display device was evaluated in the same manner as in Example 1. As a result, as in Example 1, the display device showed good results in terms of current efficiency, driving life, and fineness.

(Example 5)

In this example, as in Example 4, except that the forming step of the protective layer, the processing step of the protective layer 60 and the removing step of the protective layer 60 are changed by the method described below. An organic EL display device was manufactured by the method. Hereinafter, with reference to FIG. 6, the process of forming a protective layer, the process of processing a protective layer, and the process of removing a protective layer will be described with particular emphasis.

(1) Formation process of protective layer

First, by the same method as in Example 4, the layers were formed on the support substrate 10 up to the release layer 30. Next, an aqueous solution of polyvinyl pyrrolidone (PHP, molecular weight: 360,000), which is a water-soluble high molecular material, was mixed so that the weight concentration of PPP was 5% by weight, to prepare a PPP solution. Next, the prepared PPU aqueous solution was applied onto the release layer 30 and formed into a film by spin coating to form a first protective layer 61. At this time, the thickness of the first protective layer 61 was 500 nm. Next, silicon nitride (SiI) was formed on the first protective layer 61 by the CD method to form the second protective layer 62. At this time, the thickness of the second protective layer 62 was set to 1000 nm. Next, the photosensitive resin layer 40 was formed on the protective layer 60 by which the 1st protective layer 61 and the 2nd protective layer 62 were laminated | stacked in this order by the method similar to Example 4 (FIG. 6A). ).

(2) Processing process of protective layer

After patterning the photosensitive resin layer 40, the process of the 2nd protective layer 62 (selective removal of the 2nd protective layer 62) was performed on the conditions similar to the process (2) of Example 4 (FIG. 6B). . Next, using oxygen as a reaction gas, the first protective layer 61 not covered with the photosensitive resin layer 41 was removed under a condition of a flow rate of 20 cc, a pressure of 8 Pa, an output of 150 W, and 5 minutes. That is, the protective layer 60 was processed in this process so that the protective layer 60 which consists of the 1st protective layer 61 and the 2nd protective layer 62 is provided corresponding to the area | region of each subpixel (FIG. 6C thru | or 6). 6e).

(3) removal process of protective layer

After the photosensitive resin layer 41 was removed, the second protective layer 62 was removed under the same conditions as in the step (4) of Example 4. Next, using oxygen as a reaction gas, the first protective layer 61 was removed under conditions of a flow rate of 20 cc, a pressure of 8 Pa, an output of 150 W, and 5 minutes. Next, a part of the peeling layer 30 was removed and thinned by the method similar to Example 4. In this way, the charge transport layer 23 was formed (Fig. 6B). Thereafter, the charge injection / transport layer 24 and the second electrode 25 were formed in this order by the same method as in Example 4. In this way, an organic EL display device was obtained.

The resulting organic EL display device was evaluated in the same manner as in Example 1. As a result, as in Example 1, the display device showed good results in terms of current efficiency, driving life, and fineness.

While the present invention has been described with reference to exemplary embodiments, it will be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all modifications, equivalent structures and functions.

Claims (10)

A method of manufacturing an organic electroluminescent display device having an organic electroluminescent element comprising a first electrode and a second electrode and an organic compound layer disposed between and patterned between the first electrode and the second electrode. ,
Forming an organic compound layer to form at least the organic compound layer on the first electrode;
A step of forming a release layer for forming a release layer on the organic compound layer;
A first processing step of the release layer for patterning the release layer;
A processing step of the organic compound layer for removing the organic compound layer in a region not covered with the release layer processed in the first processing step of the release layer; And
A second processing step of the release layer for removing a part of the release layer;
The release layer includes a vapor deposition film made of a charge-transporting organic compound, and is soluble in a polar solvent, wherein the organic electroluminescent display device is manufactured.
The method of claim 1,
The said polar solvent contains water and the solvent obtained by mixing the polar solvent miscible with the said water, The manufacturing method of the organic electroluminescent display apparatus.
The method of claim 1,
The manufacturing method of the organic electroluminescent display apparatus which used the film formed in the 2nd process process of the said peeling layer as a charge transport layer.
The method of claim 1,
The said peeling layer contains the heterocyclic compound, The manufacturing method of the organic electroluminescent display apparatus.
The method of claim 1,
The said peeling layer contains the charge transport compound which has an electron-withdrawing group, The manufacturing method of the organic electroluminescent display apparatus.
The method of claim 1,
The said peeling layer contains the compound which has condensation ventilation with m-terphenyl group, The manufacturing method of the organic electroluminescent display apparatus.
The method of claim 1,
A method for producing an organic electroluminescent display device according to claim 1, wherein the following formula is established:

Where n is the ratio of the etching rate.
The method of claim 1,
The method of manufacturing an organic electroluminescent display device, further comprising a step of forming a layer containing an alkali metal after the second processing step of the release layer.
An organic electroluminescent display manufactured by the manufacturing method according to claim 1.
Shooting unit for taking an image;
A memory for recording the photographed image;
An image signal processing circuit for converting the image photographed by the photographing unit and the image information recorded in the memory into an image signal;
A CPU (central processing unit) for controlling the photographing unit, the memory, and the image signal processing circuit;
An operation unit for inputting a signal to control the CPU; And
A display device for displaying the video signal transmitted from the video signal processing circuit as a video according to the signal from the CPU;
The display device is an organic electroluminescent display device according to claim 9.

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