KR20130138174A - Donor substrate for transfer, device manufacturing method using the substrate, and organic el element - Google Patents

Abstract

This invention is a transfer donor substrate which has a board | substrate and a photothermal conversion layer, and whose surface is a rough surface. As a result, a film of uniform transfer material is formed, and a device capable of high-precision fine patterning can be manufactured. In addition, the present invention is an organic EL device in which at least a part of the organic compound layer is formed by using a transfer method, with little light emission luminance unevenness or film thickness unevenness in the light emitting region. Thereby, the organic electroluminescent element excellent also in durability can be provided.

Description

A donor substrate for transfer, a manufacturing method of a device using the same, and an organic EL element TECHNICAL FIELD

The present invention relates to a transfer donor substrate for a thin film constituting an organic EL element, a method for manufacturing a device using such a transfer donor substrate, and an organic EL element.

The organic EL device is one in which electrons injected from the cathode and holes injected from the anode are recombined in the organic light emitting layer sandwiched by the anode. The organic EL device emitting light in this manner is thin since the research results as shown in Non-Patent Document 1 and high brightness under low driving voltage, and by using various organic materials in the light emitting layer, red (R), green (G), In the point that it is possible to obtain various light emission colors including the three primary colors of blue (B), the practical application of color display has been advanced, and various technologies have been demanded accordingly. One of them is a final product, a thin film having a typical film thickness of 0.1 µm or less on a device substrate for forming an organic EL element, and a technique of forming a light-emitting layer finely patterned with high precision for every three primary colors.

Conventionally, wet processes (coating methods), such as a photolithography method, an inkjet method, and a printing method, have been used for the fine patterning of a thin film. However, in the wet process, when a photoresist, ink, or the like is applied to a previously formed base layer, it is difficult to completely prevent a shape change, undesired mixing, etc. of a very thin base layer, and uniform film thickness of the thin film dried from the wet state. It was also difficult to achieve sex. On the other hand, several kinds of dry processes are put to practical use or proposed. Among them, the mask deposition method is to deposit a deposition mask in which a precise hole is formed in a metal plate, and deposit each light emitting material on the device substrate by using it as a mask. This method is difficult to achieve both the enlargement of the color display and the precision of the holes, and the adhesion between the device substrate and the deposition mask tends to be impaired due to the enlargement.

As a dry process corresponding to the enlargement of a color display, once the R, G, B light emitting material is apply | coated to the transfer donor sheet (donor film or donor substrate) once, the fine-patterned transfer material is formed, and the transfer material is a device Deposition transfer to a substrate has been developed.

For example, Patent Document 1 discloses a method in which a photothermal conversion layer is formed on a donor substrate, and R, G, and B organic EL materials are divided and painted by a printing method, and the laser beam is irradiated to the photothermal conversion layer and collectively transferred. It is.

Moreover, in patent document 2, 3, a partition pattern is formed on the photothermal conversion layer of a donor substrate, the organic electroluminescent material of R, G, B is apply | coated by methods, such as an inkjet method, and a laser is applied to a photothermal conversion layer on it. A method of collectively transferring an organic EL material by irradiation is described.

On the other hand, Patent Document 4 discloses that the organic EL material formed on the device substrate by selectively irradiating a laser to transfer the organic EL material by selectively irradiating only a portion of the organic EL material formed by a method such as an inkjet method on the donor substrate with a laser. A method of reducing film thickness nonuniformity is described.

Japanese Patent Publication No. 2008-235011 International publication WO 2009/154156 pamphlet Japanese Patent Publication No. 2009-187810 Japanese Patent Publication No. 2009-146715

 "Applied Physics Letters," (US), 1987, Vol. 51, No. 12, pp. 913-915

However, in the method described in Patent Document 1, since no partition pattern is formed on the donor substrate, there is a problem in that when the RGB is applied in a solution state, it is mixed with the next material or the solvent vapor during drying redissolves the next material. It was difficult to divide and apply an organic EL material with high precision. In addition, in the methods described in Patent Documents 2 and 3, when forming a transfer material in each compartment pattern by the inkjet method, a local film thickness nonuniformity in the form of a so-called "coffee stain" occurs, and when the transfer film is transferred to the device substrate, There was a problem that thickness unevenness was transferred.

On the other hand, Patent Document 4 discloses a method for producing a device substrate having a low film thickness nonuniformity by transferring only a portion having a low film thickness nonuniformity of an organic EL material formed on a donor substrate as shown in Fig. 17A. However, as shown in Fig. 17 (b), even when only a portion of the organic EL material formed on the donor substrate has a small film thickness nonuniformity, the transfer region of the donor substrate is small with respect to the pixel region of the device substrate. This causes a problem of extremely thinning in the vicinity of the insulating layer around the pixel. In addition, even when the transfer region of the donor substrate is enlarged as shown in Fig. 17C, the extremely thick organic EL material is also transferred near the partition wall of the donor substrate, so that the film thickness of the organic EL material transferred to the device substrate becomes uneven. Had a problem.

In the present invention, this problem is solved, and an object thereof is a donor substrate for transferring a transfer material to a device substrate by irradiating light represented by a laser, whereby a film of a uniform transfer material can be formed, and high-precision fine patterning is possible. It is providing the method which manufactures the donor substrate and the device represented by organic electroluminescent element using such a donor substrate. Moreover, it is providing the organic electroluminescent element which has the light emission luminance nonuniformity and film thickness nonuniformity of a light emitting area | region, and is excellent also in durability.

MEANS TO SOLVE THE PROBLEM As a result of studying the said subject, the film thickness nonuniformity generate | occur | produced in the drying process of a solvent can be eliminated by adjusting the roughness of the surface of the photothermal conversion layer of a donor substrate, and light emission luminance nonuniformity also in the device substrate of a high aperture ratio. It discovered that this little organic electroluminescent element could be produced and came to this invention.

That is, one configuration of the present invention is a transfer donor substrate, which is a transfer donor substrate having a substrate and a photothermal conversion layer formed on the substrate, wherein the surface of the photothermal conversion layer is a rough surface.

Further, another configuration of the present invention is based on an organic EL element, and has an organic compound layer including a light emitting layer sandwiched between at least a pair of electrodes, and at least a part of the organic compound layer is formed in an organic EL element formed using a transfer method. It is characterized in that the width of the insulating layer of the pixel is less than 40 µm and the light emission luminance nonuniformity of the light emitting region in the subpixel is ± 20% or less. Further, in an organic EL device having an organic compound layer including a light emitting layer sandwiched between at least a pair of electrodes, wherein at least a portion of the organic compound layer is formed by using a transfer method, the width of the insulating layer of the subpixel is less than 40 µm, and It is characterized by the film thickness nonuniformity of the light emitting area | region in a subpixel among the organic compound layers formed using the transcription | transfer method.

(Effects of the Invention)

According to the transfer donor substrate of the present invention, it is possible to produce a transfer donor substrate on which a transfer material having a uniform film thickness is formed by a coating method, and when the transfer is performed using this donor substrate, high performance is achieved without deteriorating device performance. The manufacture of road fine patterned devices is possible.

In addition, according to the organic EL element of the present invention, since there is little light emission luminance nonuniformity, it is possible to realize the display device which is high quality display and excellent in durability.

1 is an enlarged cross-sectional view showing an example of a typical structure of a device substrate on which an organic EL element is formed.
2 is an enlarged cross-sectional view showing an example of a method of forming a transfer film on a device substrate using the donor substrate in the embodiment of the present invention.
3 is an enlarged plan view in FIG. 2.
It is sectional drawing explaining formation of the transfer material in embodiment of this invention.
5 is a cross-sectional view showing an example of formation of a transfer material in an embodiment of the present invention.
It is sectional drawing which shows an example of the patterning method in embodiment of this invention.
It is sectional drawing explaining an example of embodiment of this invention.
It is a top view explaining an example of embodiment of this invention.
It is sectional drawing explaining an example of the light irradiation method of this invention.
It is sectional drawing explaining the problem in the conventional light irradiation arrangement.
It is sectional drawing explaining the difference of the patterning precision of the light emitting layer in this invention technique and a prior art.
It is sectional drawing explaining the difference of the edge shape of a light emitting layer in a transfer method and a vapor deposition method.
It is a top view which shows the pixel of the device substrate in embodiment of this invention.
It is sectional drawing which shows an example of the patterning method of batch transfer in embodiment of this invention.
It is a perspective view which shows an example of the light irradiation method in embodiment of this invention.
It is a top view photograph of the formation process of the transfer material in the Example of this invention.
17 is a cross-sectional view showing an example of a conventional method of forming a transfer film on a device substrate using a donor substrate having a smooth surface.

EMBODIMENT OF THE INVENTION Hereinafter, the preferable form for implementing this invention is demonstrated, referring drawings. In addition, the enlarged sectional drawing or enlarged plan view used in this specification has shown the RGB subpixel which comprises the pixel which is the minimum unit of a color display. In addition, the magnification of the vertical direction (substrate surface vertical direction) is expanded compared with the horizontal direction (substrate surface direction) of an expanded sectional view for clarity. As a representative example of the device, a donor substrate according to an embodiment of the present invention, which is preferable for forming a device substrate 10 having a typical structure in which an organic EL element is formed, and then forming a device on the device substrate 10 by transfer ( 30), the manufacturing method of a device is demonstrated centering on the transfer process using the donor substrate 30 next.

(1) device substrate (10)

1 is an enlarged cross-sectional view showing an example of a typical structure of a device substrate 10 in which an organic EL element is formed. The device substrate 10 includes an active matrix circuit composed of a TFT 12 (including a lead electrode), a planarization layer 13, and the like on a support 11 such as a glass plate. Above them, the first electrode 15 / hole transport layer 16 / light emitting layer 17 / electron transport layer 18 / second electrode 19 constituting the organic EL element is formed. In the example of FIG. 1, the light emitting layer 17 is composed of three types of RGB light emitting layers 17R, 17G, and 17B, and they are partitioned in the horizontal direction. At the end of the first electrode 15, an insulating layer 14 which prevents occurrence of a short circuit at the electrode end and defines a light emitting area is formed. The element configuration of the organic EL element is not limited to this example, and for example, only one layer of the light emitting layer 17 having both a hole transport function and an electron transport function between the first electrode 15 and the second electrode 19 is provided. The hole transport layer 16 may be formed, and the electron transport layer 18 of the hole injection layer and the hole transport layer may have a laminated structure of a plurality of layers of an electron transport layer and an electron injection layer, and the light emitting layer 17 may have an electron transport function. In this case, the electron transport layer 18 may be omitted. The first electrode 15 / electron transport layer 18 / light emitting layer 17 / hole transport layer 16 / second electrode 19 may be stacked in this order. In addition, all of these layers may be a single | mono layer or multiple layers. Although not shown, after the formation of the second electrode 19, the formation of the protective layer, the formation of the color filter, the sealing, or the like may be performed using a known technique or the transfer process of the present embodiment described later.

The light emitting layer 17 may be a single layer or a plurality of layers, and the light emitting material of each layer may be a single material or a mixture of a plurality of materials. From the viewpoint of luminous efficiency, color purity and durability, the light emitting layer 17 is preferably a single layer structure of a mixture of a host material and a dopant material.

The hole transport layer 16 may be a single layer or a plurality of layers, and each layer may be a single material or a mixture of a plurality of materials. A layer called a hole injection layer is also included in the hole transport layer 16. In view of hole transportability (low driving voltage) and durability, an acceptor material for promoting hole transportability may be mixed in the hole transport layer 16.

The electron transport layer 18 may be a single layer or a plurality of layers, and each layer may be a single material or a mixture of a plurality of materials. A layer called a hole blocking layer or an electron injection layer is also included in the electron transport layer 18. In view of electron transportability (low drive voltage) and durability, a donor material that promotes electron transportability may be mixed in the electron transport layer 18. The layer called an electron injection layer is often discussed as this donor material. The transfer material for forming the electron transport layer 18 may be made of a single material or a mixture of a plurality of materials.

As a material of these light emitting layer 17, the hole transport layer 16, and the electron transport layer 18, the well-known material of patent document 1 can be used, for example.

Examples of donor materials include alkali metals such as lithium, cesium, magnesium and calcium, alkaline earth metals, various metal complexes such as quinolinol complexes, oxides and fluorides such as lithium fluoride and cesium oxide, tetrathiafulvalene (TTF), and the like. The electron donating low molecular weight material of can be illustrated. The electron transporting material or the donor material is one of materials which are likely to change in performance due to the combination with the light emitting layer 17.

At least one of the first electrode 15 and the second electrode 19 is preferably transparent in order to extract light emitted from the light emitting layer 17. In the case of the bottom emission which extracts light from the first electrode 15, the second electrode 19 is transparent in the case of the top emission where the first electrode 15 extracts the light from the second electrode 19. Do. For the transparent electrode material and the other electrode, a conventionally known material can be used, for example, as described in JP-A-11-214154.

Such an organic EL element is generally not limited to an active matrix type in which the second electrode 19 is formed as a common electrode, and is, for example, a stripe shape in which the first electrode 15 and the second electrode 19 cross each other. It may be a simple matrix form made of electrodes or a segment form in which the display portion is patterned to display predetermined information. Examples of these applications include televisions, personal computers, monitors, clocks, thermometers, audio equipment, automotive display panels, and the like.

(2) donor substrate 30

Next, the donor substrate 30 by embodiment of this invention which is suitable for forming the thin film layer which forms a device in the device substrate 10 by transfer is demonstrated. 2 and 3 are enlarged cross-sectional views and enlarged plan views illustrating an example of a method of forming the light emitting layer 17 on the device substrate 10 using the donor substrate 30. The donor substrate 30 includes the support 31, the photothermal conversion layer 33 formed on the support 31, the partition pattern 34 formed by laminating the photothermal conversion layer 33, and the partition pattern 34. The transfer material 37 partitioned off is provided. 2 and 3, the transfer material 37 of the donor substrate 30 is made of transfer materials 37R, 37G, 37B of three kinds of RGB light emitting materials partitioned in the horizontal direction, and the device substrate ( 10 corresponds to the three types of light emitting layers 17R, 17G, and 17B. 3 is the figure which looked at the shape of the light irradiation in FIG. 2 from the support body 31 side of the donor substrate 30. As shown in FIG. Since there is a photothermal conversion layer 33 formed on the entire surface, the partition pattern 34 and the transfer materials 37R, 37G, and 37B are not actually seen from the support 31 side, but are dotted to explain the positional relationship with light irradiation. As shown. The irradiated light has a rectangular shape and is irradiated to cover the transfer materials 37R, 37G and 37B, and scanned in a direction perpendicular to the arrangement of the transfer materials 37R, 37G and 37B. The irradiated light may be scanned relatively, and the light itself may be moved, or the set of the donor substrate 30 and the device substrate 10 may be moved, or both. Hereinafter, the support 31, the photothermal conversion layer 33, the transfer material 37, and the partition pattern 34 will be described in order.

The support 31 of the donor substrate 30 has a low light absorption rate, and is not particularly limited as long as it is a material capable of stably forming the photothermal conversion layer 33, the partition pattern 34, and the transfer material 37 thereon. . Depending on the conditions, it is possible to use a film of a resin material. As the resin material, polyester, polyethylene, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyacryl, polysulfone, polyethersulfone, polyphenylene sulfide, polyimide, polyamide, polybenzoxazole, polyepoxy, polypropylene , Polyolefin, aramid resin, silicone resin and the like can be exemplified.

A glass plate is mentioned as a preferable support body 31 from a chemical and thermal stability, a dimensional stability, and mechanical strength transparency. It can select from soda lime glass, alkali free glass, lead containing glass, borosilicate glass, aluminosilicate glass, low expansion glass, quartz glass, etc. according to conditions. As described later, when the transfer process is carried out in a vacuum, a small amount of gas discharge from the support 31 is required, and therefore, the glass plate is particularly preferable from this point.

In order to prevent the patterning accuracy from deteriorating due to the difference in thermal expansion due to temperature change when transferring the transfer material by opposing the device substrate 10 and the donor substrate 30, the device substrate 10 and the donor substrate 30 may be separated. It is preferable that the difference of the thermal expansion coefficients between support bodies 11 and 31 is 10 ppm / degrees C or less, and it is more preferable that these support bodies 11 and 31 consist of the same material. In addition, the difference in thickness of both is not specifically limited.

Even if the photothermal conversion layer 33 is heated to a high temperature, it is necessary to accept the temperature rise (thermal expansion) of the support 31 itself within an acceptable range, so that the heat capacity of the support 31 is sufficiently larger than that of the photothermal conversion layer 33. desirable. Therefore, it is preferable that the thickness of the support body 31 is 10 times or more of the thickness of the photothermal conversion layer 33. The allowable range cannot be expressed uniformly because it depends on the size of the transfer region, the required precision of patterning, and the like, but for example, the photothermal conversion layer 33 rises from room temperature to 300 deg. When it is desired to be suppressed to 3 ° C. or less, which is 100, when the volume heat capacity of the light-heat conversion layer and the support is about the same, the thickness of the support 31 is preferably 100 times or more of the thickness of the light-heat conversion layer 33, and the support ( When it is desired to suppress the temperature rise of 31) to 1 ° C or less, which is 1/300 of 300 ° C, the thickness of the support 31 is more preferably 300 times or more of the thickness of the photothermal conversion layer 33. In a typical case where the volume heat capacity of the photothermal conversion layer is about twice that of the support, the thickness of the support is preferably 200 times or more, more preferably 600 times or more of the thickness of the photothermal conversion layer. By doing so, even if it enlarges, the amount of dimensional displacement due to thermal expansion is small, contributing to high-precision fine patterning.

Next, the photothermal conversion layer 33 of the donor substrate 30 is demonstrated. The photothermal conversion layer 33 is not particularly limited as long as it absorbs light efficiently, generates heat, and is a stable material and structure with respect to generated heat. Inorganic thin films, such as a thin film which disperse | distributed carbon black, graphite, titanium black, an organic pigment, metal particle, etc. to resin, or a metal thin film can be used. Since the light-to-heat conversion layer 33 may be heated to about 300 degreeC as mentioned later, it is preferable that the light-to-heat conversion layer 33 consists of an inorganic thin film which is excellent in heat resistance, and consists of a thin film of a metallic material in light absorption or film-forming property. Is particularly preferred. Metallic materials include tungsten, tantalum, molybdenum, titanium, chromium, gold, silver, copper, platinum, iron, zinc, aluminum, cobalt, nickel, magnesium, vanadium, zirconium, silicon, carbon, and the like, alloys or laminates thereof. Can be used. An antireflection layer can be formed on the support 31 side of the photothermal conversion layer 33 as necessary. In addition, an antireflection layer may be formed on the surface on the light incident side of the support 31. As the anti-reflection layer, an optical interference thin film using a refractive index difference is preferably used, and single or mixed thin films such as silicon, silicon oxide, silicon nitride, zinc oxide, magnesium oxide, titanium oxide, and laminated thin films thereof can be used.

It is important that the photothermal conversion layer 33 has a fine uneven structure on the surface, that is, the surface is rough. Here, the rough surface in this invention shows that the surface becomes rough so that local film thickness nonuniformity may not generate | occur | produce in the film after drying, when apply | coating the solution containing a transfer material to a donor substrate as mentioned later.

4 is a diagram illustrating formation of a dry film of the transfer material 37 when the donor substrate 30 is applied.

As shown in Fig. 4A, when a substrate having a light-heat conversion layer 33 having a smooth surface is used, film thickness unevenness due to a so-called "coffee stain" phenomenon is also likely to occur. That is, when the solution of the transfer material is added dropwise, the solvent is flowing from the center to the periphery in order to replenish the amount of the evaporation from the periphery because the rate of drying of the solvent is faster than the periphery of the droplet. At this time, the solute (transfer material) is also carried to the periphery, resulting in a film having a high periphery.

On the other hand, as shown in FIG.4 (b), when the donor board | substrate with which the photothermal conversion layer 33 is a rough surface is used, the movement of the solution from the center to a peripheral part is prevented by the unevenness | corrugation of the surface of the photothermal conversion layer 33. FIG. Therefore, the solute is uniformly dispersed and precipitated on the surface of the donor substrate 30, and local film thickness nonuniformity can be suppressed.

Since the film thickness nonuniformity of the transfer material 37 shown in FIG. 4 (a) is a result of localized solidification of the solute, the transfer film 27 after transfer to the device substrate 10 also tends to remain as the same film thickness nonuniformity, and organic Even when the EL element is manufactured, uneven luminous luminance unevenness occurs in a part of the compartment.

On the other hand, in Fig. 4 (b), the film thickness of the transfer material 37 is made more uniform than in Fig. 4 (a), and the film thickness nonuniformity of the transfer film 27 is suppressed even after transferring to the device substrate 10. Light emission luminance nonuniformity at the time of manufacturing an element also does not arise. The uniform film thickness here means that the molten mass on the substrate is substantially uniform. Further, even if a slight film thickness nonuniformity following the unevenness of the light-to-heat conversion layer 33 existed in the transfer material 37 to some extent, the transfer material was released to the molecular (atomic) level at the time of transfer by using the deposition mode described later. Since the film is deposited on the device substrate 20 after sublimation in a state, the film thickness nonuniformity of the transfer film 27 becomes uniform, so that the light emission luminance nonuniformity when the organic EL device is manufactured is not a problem.

Further, when the RGB transfer material is sequentially formed in a plurality of sections, the surface of the photothermal conversion layer 33 is roughened to reduce the movement of the transfer material 37 due to dry vapor of the solvent, thereby suppressing the occurrence of film thickness nonuniformity. You may.

5 is a diagram explaining the occurrence of film thickness nonuniformity when the transfer material 37 is applied. First, the case where the board | substrate which has the light-heat conversion layer 33 with a smooth surface is used as shown to FIG. 5 (a) is demonstrated. A solution of the transfer material 37R is applied and dried. Next, a solution of the transfer material 37G is applied and dried. Then, a solution of the transfer material 37B is applied and dried.

At this time, when the transfer material 37G is dried, the transfer material 37R previously formed is affected by the vapor of the solvent which volatilizes, and thus the transfer is likely to occur. The same applies to the transfer material 37G (or 37R) when the transfer material 37B is applied. This movement causes film thickness irregularities in the transfer materials 37R and 37G.

On the other hand, when the surface of the photothermal conversion layer 33 is a rough surface, as shown to FIG. 5 (b), it transfers when the solution of the transfer material 37R is apply | coated and dried, and then the solution of the transfer material 37G is apply | coated. Even if the transfer material 37R is affected by the vapor of the solvent which volatilizes when the material 37G is dried, the transfer of the transfer material 37R is prevented due to the unevenness of the surface of the photothermal conversion layer 33, so that the film thickness unevenness is prevented. It is possible to do very little. The same applies to the transfer material 37G (or 37R) when the transfer material 37B is applied.

In addition, even if it apply | coats to several division in batches of RGB, application | coating nonuniformity can be suppressed by making the surface of the photothermal conversion layer 33 into a rough surface. It is a figure explaining the generation | occurrence | production of application | coating nonuniformity when apply | coating to a several donor in batch collectively on a smooth donor substrate. In the transfer area 38, many RGB partitions are arranged. When the transfer material 37 of RGB is apply | coated collectively to these divisions, the flow of steam from a center to the outer side will generate | occur | produce by the difference in the vapor pressure on the donor substrate 30, and the transfer material of the outer periphery of the donor substrate 30 will be made of the vapor | steam. Under influence, the film is biased outward. In FIG. 6, a portion in which the transfer material flows to the inner part of the donor substrate 30 to the inner part of the donor substrate 30 to the inner part of the donor substrate 30 partially exposes the phenomenon. By the way, when the donor substrate 30 which is rough surface is used, even if it is influenced by dry vapor, solute movement is hard to generate | occur | produce, and the film thickness nonuniformity in surface becomes uniform.

In the formation method of these transfer materials 37, the film thickness after drying of the film | membrane which the at least 1 type of transfer material 37 consists of a low molecular weight material whose molecular weight is less than 1000, and consists of said low molecular material material is 100 nm or less, and also 50 nm It is especially effective in manufacture of the following organic EL thin film. This is because such low-molecular materials have small intermolecular interactions, so that the molecules are entangled with each other, which makes them easier to move than high molecular materials with large intermolecular interactions. In addition, the film thickness of a transcription | transfer material can be calculated | required from the level | step difference with a photothermal conversion layer, for example by measuring a surface shape by the styling method, such as an atomic force microscope. In addition, if the dependence of the fluorescence intensity and the film thickness observed upon irradiation with ultraviolet rays is known, it is also possible to infer the film thickness of the transfer material when the surface of the substrate is observed with a fluorescence microscope.

Moreover, in addition to the method of making the surface of a donor substrate into a rough surface like this invention, the method of suppressing the film thickness nonuniformity of a transfer material is considered. One example is a method of applying the transfer materials 37R, 37G, 37B sequentially, and then applying the solvent on the transfer materials 37R, 37G, 37B collectively, and once drying the solution, and then drying at the same time. . However, this method has a problem that since the coating step occurs twice, the amount of impurities contained in the solution or the solvent increases. Moreover, the method of drying simultaneously three types of transfer materials 37R, 37G, 37B using a high boiling point solvent is also mentioned. However, this method has a problem that the process time becomes long. Moreover, when using the transfer material which is easy to crystallize, since it becomes large crystal grain after drying, it cannot become a uniform thin film and there exists a problem that the film thickness after transfer becomes nonuniform. For this reason, it is more preferable to use the system of this invention as a system of suppressing film thickness nonuniformity.

The degree to which the photothermal conversion layer 33 is a rough surface can be represented by the arithmetic surface roughness (it describes as Ra below) of the surface of the photothermal conversion layer 33. FIG. In addition, the arithmetic mean roughness in this invention is a ten-point average roughness obtained when it measures by 1.0 mm of measurement length based on JIS B0601-1994 with a surface roughness shape measuring instrument. In this invention, it is preferable that Ra of the surface of the photothermal conversion layer 33 is 30 nm or more. If Ra of the surface of the photothermal conversion layer 33 is 30 nm or more, it can exhibit more effective in suppression of a film thickness nonuniformity. More preferably, it is 50 nm or more, More preferably, it is 100 nm or more, Especially preferably, it is 150 nm or more.

On the other hand, if the Ra on the surface of the photothermal conversion layer 33 is too large, the solution will settle in the recess when the transfer material 37 is applied, so that the film after drying becomes discontinuous and the film thickness unevenness after the transfer becomes large. Occurs. In order to prevent the solution from accumulating in the recess, the value of the thickness of the coating solution may be larger than Ra on the surface of the photothermal conversion layer 33. That is, even if Ra of the surface of the photothermal conversion layer 33 is larger than the value of the film thickness after drying, it does not interfere. In this case, film thickness nonuniformity arises by the unevenness | corrugation of the photothermal conversion layer 33, but the "coffee stain phenomenon" and the movement of the transfer material 37 by solvent vapor do not occur. In addition, when the deposition mode is used at the time of transfer as described above, the film thickness of the transfer film 27 becomes uniform, so that the film thickness nonuniformity is not a problem. Specifically, Ra of the photothermal conversion layer 33 is preferably 4 µm or less, more preferably 1 µm or less, still more preferably 500 nm or less, particularly preferably 250 nm or less. If it is this range, when the solution of reasonable concentration is apply | coated in order to obtain the transfer material of desired thickness, the value of the thickness of a coating solution can be made larger than Ra of the photothermal conversion layer 33.

It is preferable that the uneven | corrugated average space | interval (it shows below Sm) of a donor substrate surface is 20 micrometers or less. In addition, the arithmetic mean roughness in this invention is an uneven | corrugated average space | interval obtained when it measures by 1.0 mm of measurement length based on JIS B0601-1994 with a surface roughness shape measuring instrument. When the average thickness of the unevenness is set to 20 µm or less, the density of the unevenness on the surface becomes larger and the movement of the transfer material is more easily inhibited. As a result, local film thickness nonuniformity is easily suppressed. Moreover, the phenomenon which the nonuniformity by the coffee stain phenomenon generate | occur | produces in the range of 20 micrometers does not generate | occur | produce, either.

As the formation method of the photothermal conversion layer 33, a well-known technique can be used according to materials, such as a spin coat, a slit coat, vacuum deposition, EB deposition, sputtering, and ion plating.

There are two ways to roughen the surface of the photothermal conversion layer 33. One is a method of forming the photothermal conversion layer 33 on the roughened support 31 in advance to be substantially uniform in accordance with the irregularities of the surface of the support 31. In this method, Ra on the surface of the support body 31 can be transferred to Ra on the surface of the photothermal conversion layer 33. For example, by making Ra of the surface of the support body 31 into 30 nm or more, the photothermal conversion layer 33 can also adjust Ra of the surface to 30 nm or more. Therefore, it is preferable to set Ra of the surface of the side in which the photothermal conversion layer of a support body is formed as the value calculated | required as Ra of the surface of the photothermal conversion layer 33. FIG. For example, 30 nm or more is preferable, More preferably, it is 50 nm or more, More preferably, it is 100 nm or more, Especially preferably, it is 150 nm or more.

The method of roughening the surface of the support 31 is not particularly limited, and mechanical roughening by sand blasting, chemical etching by mixing with hydrofluoric acid, buffered hydrofluoric acid and other acids, and glass powder are applied to the surface and melted at high temperatures. Known techniques, such as the method of making it, can be used. These treatments can be adjusted so that the desired Ra is obtained as Ra increases as the conditions such as pressure and treatment time are enhanced. In addition, in order to make Sm into 20 micrometers or less, it can adjust by making the particle size of a blast material small when carrying out mechanical roughening by sandblasting.

As a method of forming the photothermal conversion layer 33 substantially uniformly in accordance with the unevenness | corrugation of the surface of the support body 31, sputtering method is mentioned preferably. Since the detailed conditions vary depending on the material, it cannot be said uniformly. For example, in the case of tantalum, for example, it is preferable to form the gas pressure at 0.2 kPa and an input power of 1 kW in an Ar gas atmosphere. Of course, it is not limited to this condition.

The other is a method of roughening the surface after forming the photothermal conversion layer 33 whose surface is almost smooth by a known method. The method is not particularly limited, and known techniques such as mechanical roughening by sand blasting, chemical etching, and changing conditions of gas pressure, input power, and film forming temperature during sputtering film formation can be used.

However, in the method of roughening the photothermal conversion layer 33 directly, when the light irradiation is performed, variation in the surface temperature occurs in the thick portion and the thin portion of the photothermal conversion layer so that the heat is uniformly applied to the transfer material. In view of difficulty, it is preferable to roughen the surface of the former support body 31 to uniformly form the photothermal conversion layer 33 in accordance with the unevenness of the surface.

Since the photothermal conversion layer 33 needs to give sufficient heat for sublimation of the transfer material 37, the heat capacity of the photothermal conversion layer 33 is preferably larger than that of the transfer material 37. Therefore, it is preferable that the thickness of the photothermal conversion layer 33 is thicker than the transfer material 37, and it is more preferable that it is 5 times or more of the thickness of the transfer material 37. As a numerical value, 0.02-2 micrometers is preferable and 0.1-1 micrometer is more preferable. Since the photothermal conversion layer 33 preferably absorbs 90% or more of the light and 95% or more, it is preferable to design the thickness of the photothermal conversion layer 33 to satisfy these conditions.

The light-to-heat conversion layer 33 may be formed in the part in which the transfer material 37 exists, and may be patterned so that it may become discontinuous in the lower part of the partition pattern 34, for example. When the partition pattern 34 lacks adhesiveness with the photothermal conversion layer 33, adhesiveness with the support body 31 can be improved in this way. When the photothermal conversion layer 33 is patterned, it is not necessary to have the same shape as the partition pattern 34, the partition pattern 34 may be a lattice shape, and the photothermal conversion layer 33 may be a stripe shape.

7, the partition pattern 34 is formed on the light-heat conversion layer 33a, and then the material of the light-heat conversion layer 33a is formed entirely on the donor substrate 30 to form the partition pattern 34. As shown in FIG. By coating (photothermal conversion layer 33b), it is also possible to prevent the partition pattern material from mixing as an impurity on the donor substrate 30, whereby impurities of the partition pattern material are not transferred when transferring to the device substrate. This will not adversely affect device performance.

In the case of this configuration, Ra on the surface of the previously roughened support body 31 is first transferred to Ra on the surface of the photothermal conversion layer 33a, and Ra on the surface of the photothermal conversion layer 33a is converted into a photothermal conversion layer ( By further transferring to Ra of the surface of 33b), Ra of the surface of the photothermal conversion layer 33b can be adjusted to 30 nm or more.

8, after forming the partition pattern 34 directly on the support body 31, the material of the photothermal conversion layer 33 is formed into a film on the donor substrate 30, and the partition pattern 34 is coat | covered. It may be a method. Also in this case, the method of roughening the light-heat conversion layer 33 on the roughened support body 31 beforehand is uniformly formed in accordance with the irregularities of the surface of the support body 31, and the light-heat conversion layer 33 having a smooth surface. After forming), a method of roughening the surface may be used.

Since the photothermal conversion layer 33 has a large light absorption rate, it is preferable to form the position mark of the donor substrate 30 at a suitable position inside and outside the transfer region using the photothermal conversion layer 33.

Next, the transfer material 37 formed on the donor substrate 30 is demonstrated. The transfer material of the transfer material 37 may be transferred from the donor substrate to the device substrate 10 by sublimation (including ablation sublimation) when any of an organic material and an inorganic material containing a metal is heated. The transfer material may be a precursor for thin film formation, and may be converted into a thin film forming material by heat or light before or during the transfer to form a transfer film 27. Moreover, this transfer material can form not only an organic EL element but also the thin film which comprises devices, such as an organic TFT, a photoelectric conversion element, and various sensors.

It is difficult to express the thickness of the transfer material 37 uniformly according to their function or the number of transfers. For example, the transfer material 37 for one-time transfer of donor material (electron injection material), such as lithium fluoride, has a typical thickness of 1 nm or less. In addition, the film thickness of the transfer material 37 of an electrode material may be 100 nm or more. In the case of formation of the light emitting layer 17, the thickness of the transfer material 37 for one transfer is preferably 10 to 100 nm, more preferably 20 to 50 nm.

The formation method of the transfer material 37 is not specifically limited, Dry process, such as vacuum deposition and sputtering, can also be used. It is preferable to use the coating method which apply | coats the solution which consists of a transcription | transfer material and a solvent at least in the partition pattern 34, and after drying a solvent as a method which is easy to respond to enlargement. As a specific method of the coating method, various printing such as inkjet, nozzle coating, electric field polymerization or electrodeposition, offset or flexo, flat plate, convex plate, gravure, screen, etc. can be exemplified. In particular, it is important to precisely form a quantitative transfer material 37 in each partition pattern 34, and inkjet and nozzle application can be exemplified as a particularly preferred method from this point of view.

Without the partition pattern 34, the transfer materials 37 formed from the coating liquid are in contact with each other, and the boundaries thereof are not the same, so that a mixed layer is formed. In order to prevent this, it is difficult to make the thickness of the boundary region the same as the center when the gap is formed so as not to be in contact with each other. In either case, since this boundary region cannot be transferred because it causes a deterioration of the device, it is necessary to selectively transfer an area narrower than the pattern of the transfer material 37 on the donor substrate 30. Therefore, the width of the transfer material 37 which can actually be used becomes narrow, and when producing an organic EL display, it becomes a pixel with a small aperture ratio (large area of a non-light emission area). In addition, batch transfer is impossible on account of the necessity of transfer except for the boundary region, so that if the transfer material of the transfer material 37 is different in type (for example, the transfer materials 37R, 37G, 37B) are sequentially lasered. It is necessary to irradiate and transfer independently, respectively, and high-precision position adjustment of high intensity laser irradiation is needed. This problem can be solved by collectively transferring the donor substrate 30 having the partition pattern 34 and the transfer material 37 formed from the coating liquid as described below.

When applying the solution which consists of a transcription | transfer material and a solvent to a coating method, in general, it adds surfactant, a dispersing agent, etc., and adjusts the viscosity, surface tension, dispersibility, etc. of a solution, and inks often. However, in the donor substrate 30, if these additives exist as a residue in the transfer material, it is feared that they will be taken into the transfer film 27 even during transfer and adversely affect the device performance. Therefore, it is preferable to prepare a solution so that the purity of the transfer material after drying may be 95% or more and 98% or more. Such adjustment is possible by making the ratio of the transfer material which components other than a solvent in an ink occupy for 95 weight% or more.

As the solvent, known materials such as water, alcohols, hydrocarbons, aromatic compounds, heterocyclic compounds, esters, ethers, ketones and the like can be used. In the inkjet method which is preferably used for the donor substrate 30, a relatively high boiling point solvent of 100 ° C or higher and 150 ° C or higher is used, and tetralin (tetrahydronaphthalene), in terms of excellent solubility of the transfer material, N-methylpyrrolidone (NMP), dimethylimidazolidinone (DMI), γ-butyllactone (γBL), cyclohexanone, ethyl benzoate, xylene, cumene and the like can be exemplified as preferred solvents.

In the case where the transfer material satisfies both solubility, transfer resistance, and device performance after transfer, it is preferable to dissolve the transfer material itself (hereinafter referred to as the "prototype of transfer material") in a solvent. When the prototype of the transfer material lacks solubility, the solubility can be improved by introducing a soluble group for a solvent such as an alkyl group into the prototype of the transfer material. If a soluble group is introduced into the prototype of the transfer material which is excellent in device performance, the performance may be degraded. In that case, for example, the soluble group may be detached from the heat during transfer to deposit the circular material on the device substrate 10.

In order to prevent generation of gas and incorporation of desorption substances into the transfer film when transferring the transfer material into which the soluble group is introduced, the transfer material has a soluble group for the solvent at the time of coating, and the soluble group is converted or desorbed by heat or light after the coating. It is preferable to transfer the transfer material after the transfer. For example, a material having a benzene ring or an anthracene ring can be converted into a circular material by irradiating light on a material having a soluble group as shown in formulas (1) to (2). In addition, as shown in Formulas (3) to (6), an intramolecular crosslinked structure such as an ethylene group or a diketo group may be introduced as the soluble group, and thereafter, it may be returned to the circular material by a process of desorbing ethylene or carbon monoxide. The conversion or desorption of the soluble group may be in a solution state before drying or in a solid state after drying, but in view of process stability, it is preferable to carry out in a solid state after drying. Since the circular molecules of the transfer material are often nonpolar, it is desirable that the molecular weight of the leachate is small and polar (repulsive to nonpolar circular molecules) in order not to leave the sorbent in the transfer material when the soluble group is desorbed in the solid state. Do. In addition, in order to remove oxygen and water adsorbed in the transfer material together with the desorption substance, the desorption substance is preferably easily reacted with these molecules. From these viewpoints, it is particularly preferable to convert or desorb solubilizers in the process of desorbing carbon monoxide. This method is applicable to condensed polycyclic hetero compounds in addition to condensed polycyclic hydrocarbon compounds such as naphthacene, pyrene, and perylene. Of course, these may be substituted or unsubstituted.

When the light emitting layer 17 is formed as a transfer film of the device substrate 10 and has a single layer structure of a mixture of the host material and the dopant material, the transfer material for forming the light emitting layer 17 is a mixture of the host material and the dopant material. It is preferable. In the case of using the coating method, when the transfer material 37 is disposed in the partition pattern 34, the mixed solution of the host material and the dopant material can be applied and dried to form the transfer material 37. You may apply | coat a solution of a host material and a dopant material separately. Even if the host material and the dopant material are not uniformly mixed in the step of forming the transfer material 37, both may be uniformly mixed during transfer. In addition, the concentration of the dopant material in the light emitting layer 17 of the device substrate 10 may be changed in the film thickness direction by using the difference in the sublimation temperature of the host material and the dopant material during transfer.

When producing an organic TFT element as a device, an organic semiconductor layer can be preferably patterned by this invention. As an example in which two or more kinds of transfer materials 37 are formed on the donor substrate 30, one set of circuit units is composed of two or more TFT elements, and the size (or thickness) of the organic semiconductor layer required for them is different. The transfer material group which consists of organic-semiconductor material but differs in shape (or thickness) is mentioned. Of course, it is also possible to pattern each organic semiconductor layer with the present invention for two or more TFT elements. In addition, you may pattern the source, drain, gate electrode, gate insulating layer, etc. which comprise an organic TFT element by this invention.

Next, the partition pattern 34 of the donor substrate 30 is demonstrated. The partition pattern 34 defines the boundary of the transfer material 37 and is not particularly limited as long as it is a material and a structure that is stable with respect to heat generated in the photothermal conversion layer 33. The film forming method and the patterning method of the partition pattern 34 are not particularly limited as long as they can be finely patterned with high precision, and can be produced by, for example, the known materials and manufacturing methods described in Patent Document 2.

When the application method is used when arranging the transfer material 37 in the partition pattern 34, the upper surface of the partition pattern 34 is disposed on the upper surface of the partition pattern 34 in order to prevent the solution from being mixed into other compartments or placed on the upper surface of the partition pattern 34. Liquid repellent treatment (surface energy control) can be implemented. As the liquid repellent treatment, a liquid repellent material such as a fluorine-based material may be mixed with the resin material forming the partition pattern 34, or a high concentration region of the liquid repellent material may be selectively formed on the surface or the upper surface. The partition pattern 34 may have a multilayer structure of materials having different surface energies, and the surface energy state is controlled by performing plasma treatment or UV ozone treatment with a light irradiation or a fluorine-based material-containing gas after formation of the partition pattern 34. Known techniques such as can be used.

The cross-sectional shape of the partition pattern 34 is preferably in a forward taper shape in order to facilitate the deposition of the sublimated transfer material onto the device substrate 10 uniformly. As illustrated in FIG. 2, when the same pattern as the insulating layer 14 is present on the device substrate 10, the width of the insulating layer 14 is wider than the width of the partition pattern 34. In addition, it is preferable to arrange | position so that the width | variety of the partition pattern 34 may be limited to the width | variety of the insulating layer 14 at the time of position adjustment.

The partition pattern 34 needs to be a structure which suppresses the temperature rise of the device substrate 10 as disclosed in Patent Literature 2, and the thermal conductivity thereof is preferably 1.0 W / mK or less and 0.3 W / mK or less. The volume specific heat (= density x specific heat) of the partition pattern 34 is preferably 1.0 J / cm 3 K or more. Moreover, it is preferable that the thickness of the partition pattern 34 is 5 micrometers or more from a viewpoint which suppresses the temperature rise of the device board | substrate 10, and the point which makes it difficult to mutual influence when apply | coating a transfer material. On the other hand, it is preferable that the thickness is 100 micrometers or less from the viewpoint of forming the partition pattern 34 with high precision.

(3) manufacturing method of the device

Next, the manufacturing method of the device which makes an organic EL element the representative centering on the transfer process using the donor substrate 30 is demonstrated.

In a color display, at least the light emitting layer 17 needs to be patterned, and the light emitting layer 17 is a thin film preferably patterned using the transfer process of this embodiment. Moreover, only the light emitting layers 17R and 17G among the light emitting layers 17 are patterned using the transfer process of this embodiment, and the whole surface which forms the light emitting layer 17B and the electron transporting layer 18 of R and G on it can also be formed whole. have. When it is necessary to pattern at least one layer, such as the hole transport layer 16, the electron transport layer 18, the 2nd electrode 19, etc., you may pattern using the transfer process of this embodiment. In particular, since the electron transporting material or the donor material is one of materials which are easily changed in performance due to the combination with the light emitting layer 17, the electron transporting layer 18 is preferably patterned using the transfer process of the present embodiment. In addition, although the insulating layer 14, the 1st electrode 15, TFT, etc. are often patterned by the well-known photolithographic method, you may pattern by using the transfer process of this embodiment.

Upon application of the transfer process of this embodiment, the underlying layer formed on the device substrate 10 depends on the thin film to be patterned. For example, when patterning the light emitting layer 17, the first electrode 15 and the hole transport layer 16 become a base layer on which the formation is completed. A structure such as the insulating layer 14 is not essential, but the partition pattern of the donor substrate 30 when protecting the edge portion of the first electrode 15 and opposing the device substrate 10 and the donor substrate 30 ( It is preferable that 34 is formed in advance in the device substrate 10 from a viewpoint of preventing contact with the underlying layer formed on the device substrate 10 and damaging it. For forming the insulating layer 14, a material, a film forming method, or a patterning method exemplified as the partition pattern 34 of the donor substrate 30 can be used. About the shape, thickness, and pitch of the insulating layer 14, the shape and numerical value which were illustrated by the partition pattern 34 of the donor substrate 30 can be illustrated.

As shown in FIG. 2, both substrates 10 and 30 are disposed to face each other in a state where the partition pattern 34 of the donor substrate 30 and the insulating layer 14 of the device substrate 10 are aligned. At this time, the donor board | substrate 30 and the device board | substrate 10 may be made to oppose in a vacuum, and it may draw out to air | atmosphere, maintaining the transfer space in vacuum as it is. For example, the region surrounded by these can be maintained in a vacuum using the partition pattern 34 of the donor substrate and / or the insulating layer of the device substrate 10. In this case, the vacuum sealing function may be formed in the periphery of the donor substrate 30 and / or the device substrate 10. When the underlying layer of the device substrate 10, for example, the hole transport layer 16 is formed by the vacuum process, the light emitting layer 17 is patterned by transfer, and the electron transport layer 18 is also formed by the vacuum process. It is preferable that the donor substrate 30 and the device substrate 10 face each other in a vacuum, and transfer is performed in a vacuum. In this case, the method of positioning the donor substrate 30 and the device substrate 10 with high accuracy in a vacuum, and maintaining an opposing state, for example, vacuum dropping and adhesion of the liquid crystal material used in the manufacturing process of a liquid crystal monitor Known techniques such as processes can be used. In addition, by using the photothermal conversion layer 33 formed of a good conductor, such as a metal, the donor substrate 30 can also be easily maintained by an electrostatic system.

The transfer atmosphere may be atmospheric or reduced pressure. Reactive transfer such as reacting a transfer material with an active gas such as oxygen may also be performed during transfer of the first electrode 15 and the second electrode 19 and the like. However, in order to suppress deterioration of a transfer material, it is preferable in inert gas, such as nitrogen gas, or under vacuum. If it is in an inert gas, it is possible to promote uniformity of film thickness nonuniformity at the time of transfer by controlling a pressure suitably. It is possible to particularly promote the reduction of impurity incorporation into the vacuum high surface transfer film 27 and the lowering of the sublimation temperature. In addition, the donor substrate 30 may be radiated or cooled at the time of transfer regardless of the transfer atmosphere.

The transfer irradiates the light represented by the laser from the support body 31 side of the donor substrate 30 to the photothermal conversion layer 33, and heats and sublimes the transfer material 37 by the heat generated therein. 10) deposit a transfer film. When one scan is completed by irradiating light of a predetermined size, light is irradiated to the unilluminated portion and scanned. This scan finally irradiates the transfer region.

9 is a cross-sectional view showing an example of a light irradiation method onto the donor substrate 30. The donor substrate 30 is composed of the support 31, the photothermal conversion layer 33, the partition pattern 34, and the transfer material 37 of the transfer material existing in the partition pattern 34, and the device substrate 20 is It is supposed to consist only of the support body 21.

The transfer material 37 is heated and sublimed by light irradiation from the support 31 side, and is deposited as the transfer film 27 on the support 21 of the device substrate 20.

In this embodiment, it is preferable to irradiate light to the photothermal conversion layer 33 so that at least a part of the transfer material 37 and the partition pattern 34 are simultaneously heated. By adopting such an arrangement, the temperature drop at the boundary between the partition pattern 34 and the transfer material 37 is suppressed, so that the transfer material existing at the boundary is sufficiently heated to be transferred to obtain a uniform transfer film 27.

In the present embodiment, if a material or light irradiation condition is selected, an ablation mode in which the transfer material 37 reaches the support 21 of the device substrate 20 while maintaining the film shape may be used. From the viewpoint of reducing, it is preferable to use a deposition mode in which the transfer material 37 is sublimed (evaporated) in a state of being unwound with 1 to 100 units of molecules (atoms) and transferred.

In the conventional light irradiation method shown in FIG. 10, the temperature is lowered at the boundary between the partition pattern 34 and the transfer material 37, and if the light irradiation position is shifted, the uniformity of the transfer film 27 is extremely damaged. Was. Considering the difficulty of positioning the light irradiation with high accuracy over the entire area of the substrate in the enlargement, the burden of the light irradiation apparatus is remarkably reduced in the method of the present embodiment. It is a particularly preferable transfer method of the present embodiment that the transfer material 37 is divided into a plurality of times in the film thickness direction and transferred by irradiating light onto the photothermal conversion layer 33 in a plurality of times with respect to one donor substrate 30. . This lowers not only the transfer material 37 but also the maximum attained temperatures of the partition pattern 34 and the underlying layer formed on the device substrate 20, thereby preventing damage to the donor substrate and degrading device performance.

The organic EL element produced by the transfer method using the donor substrate of this invention has the following characteristics. For example, when the transfer layer is a light emitting layer (R, G, B), the light emitting layer transferred by laser irradiation to the device substrate traces the pattern of the donor substrate. That is, as shown in Fig. 11A, when a donor substrate in which light emitting layers are patterned at regular intervals is used, the distance between adjacent light emitting layers is almost constant in the device substrate. In FIG. 11A, the broken lines extending to the portions described as R, G, and B indicate the center positions in the width direction of each light emitting layer. The distance between the center positions between adjacent light emitting layers is substantially constant. In addition, although Fig. 11 (a) exemplifies an embodiment in which laser irradiation is performed by the same method as in Fig. 2 or Fig. 3, another laser irradiation method, for example, a portion of the partition pattern and the transfer layer is irradiated with laser and then R The same results also apply to the embodiment of scanning in the array direction of the G, B, or the like.

On the other hand, the case where a light emitting layer is produced by a vapor deposition method is shown in FIG. Here, although the position adjustment of a mask is necessary at the time of vapor deposition of each of R, G, and B, it is difficult to perform the position adjustment completely. R, G, and B do not become a fixed space | interval at the site | part which the error of the mask position generate | occur | produces. 11 (c) shows a method of forming R, G and B light emitting layers on each of three donor substrates having no partition pattern and partially transferring the same. In this case, it is difficult to fully perform the position adjustment of three laser irradiations, and R, G, and B do not become fixed intervals similarly to a vapor deposition method. This shows that in the transfer method using the donor substrate of this invention, R, G, and B can be patterned with high precision, and the space | interval can be made substantially constant.

Moreover, the other characteristic of the organic electroluminescent element produced by the transfer method using the donor substrate of this invention is demonstrated. When the transfer is performed by a laser, as shown in Fig. 12 (a), the transfer destination has a characteristic that the film thickness is gently attenuated at the edge of the transfer film 27 (Fig. 12 (a), at first glance, the pattern edge becomes higher than the center. It seems to be present, but since there is a forward tapered partition pattern on the edge, the film thickness of the transfer film is gently attenuated toward the edge). On the other hand, as shown in Fig. 12 (b), in the mask deposition, the molecules of the light emitting layer fly straight from the vapor deposition source and adhere to the substrate, so that the attenuation of the film thickness at the edge is steep. By observing the edge of the transfer film in this manner, it is possible to distinguish whether it is formed by either the vapor deposition method or the transfer method.

Next, the organic EL element of this invention is demonstrated. The organic EL device of the present invention is produced by the transfer method, and even if the device substrate has a high opening ratio, a uniform transfer film is formed to exhibit excellent light emission performance. Such an organic EL element preferably has an organic compound layer including a light emitting layer sandwiched between at least a pair of electrodes, for example, and at least a part of the organic compound layer is formed by using a transfer method. It is an organic electroluminescent element to satisfy.

(1) The width of the insulating layer of the subpixel is less than 40 µm, and the light emission luminance nonuniformity of the light emitting region in the subpixel is ± 20% or less.

(2) The width of the insulating layer of the subpixel is less than 40 µm, and the film thickness nonuniformity of the light emitting region in the subpixel in the organic compound layer formed by the transfer method is ± 10% or less.

More preferably, it is an organic electroluminescent element which satisfy | fills both said (1) and (2).

In the present invention, the film thickness uniformity of the transfer film of the device substrate by the film thickness nonuniformity suppression effect of the donor substrate which is rough in the organic EL element whose width of the insulating layer of a subpixel is less than 40 micrometers, More preferably, it is 30 micrometers or less. The effect can be further improved, and an organic EL device having a film thickness nonuniformity of a light emitting region in a subpixel of a device substrate can be prepared to be ± 10% or less. As a result, the light emission luminance nonuniformity in the subpixel of the created organic EL element will be ± 20% or less.

In the present specification, the subpixel refers to a portion indicated by reference numeral 47 in FIG. 13, that is, a light emitting region of any one of the light emitting regions 37R, 37G, 37B and the insulating layer 34 constituting the pixel of the device substrate, and the same. The structural unit of one insulating layer adjacent to each other is said. In other words, the width in the x direction or the y direction of the subpixel indicates the pitch of the patterned insulating layer. In addition, the width of an insulating layer means the length of the part shown by the code | symbol 44 of FIG. 13, ie, the insulating layer of the x direction (or y direction) of a pixel.

In addition, film thickness nonuniformity and light emission luminance nonuniformity represent the error of the film thickness and brightness | luminance in the light emitting area of a subpixel as a percentage.

In other words, the film thickness nonuniformity is calculated by measuring a two-dimensional film thickness profile in a subpixel using an optical interference film thickness meter and substituting the formula (Maximum film thickness-minimum film thickness) / film thickness average value × 100. One value. The film thickness average value is a value obtained by dividing the total of the film thickness measurement values of all the measurement points in the subpixels by the measurement score of the film thickness. In addition, when film thickness measurement is difficult by the said method by the influence of the refractive index difference between layers being small, etc., the cross-sectional shape of organic electroluminescent element is observed by SEM, TEM, etc., and the film thickness of a light emitting layer is read from the cross-sectional profile, and it substituted in the said formula. The film thickness nonuniformity may be calculated.

In addition, the light emission luminance nonuniformity is determined by using the FPD module inspection apparatus in which the distances in the x direction and the y direction are 20 µm (four points in total) from the four corners of the subpixels, and the x, y, and diagonal directions of the points. A total of nine points (the luminance measurement points 48 in FIG. 13) of the intermediate points (5 points in total) were measured at a spot diameter of 30 占 퐉, and substituted into an equation of (maximum luminance-minimum luminance) / luminance average value x 100. It is the calculated value. The luminance average value is a value obtained by dividing the total of nine luminance measurement values in a subpixel by nine (the number of luminance measurement points 48 in FIG. 13).

In the case of producing a large-scale panel or a high-resolution panel in an organic EL device, it is necessary to design a high aperture ratio and a small width of the insulating layer. For example, in the case of a full high-vision television having a size of 37 inches. The design value is, for example, a subpixel width of 100 m, a light emitting area width of 80 m, and an insulating layer width of 20 m (opening width ratio of 80%). When adjusting the position of the donor substrate and the device substrate, it is preferable that the width of the partition pattern is smaller than the width of the insulating layer, so that the width of the light emitting region of the donor substrate is, for example, 90 µm and the width of the partition pattern is 10 µm. do. In this case, when a coating film is formed on a donor substrate with a smooth surface, local film skew occurs in a range of about 10 µm from the partition wall, so that the film thickness unevenness also increases in the device substrate of the transfer destination. In addition, even if only the portion where the local nonuniformity does not occur is transferred, the film thickness near the insulating layer becomes very small as described above. For this reason, the organic electroluminescent element whose film thickness nonuniformity of the light emitting area | region in the subpixel of a device board | substrate is ± 10% or less cannot be produced, and the luminescence brightness nonuniformity in the subpixel of organic electroluminescent element ± 20% or less cannot be achieved.

In order to transfer the opening width ratio of a donor substrate higher than this and to transfer a part with few unevenness, for example, designing a light emitting area width to 95 micrometers and a partition pattern width to 5 micrometers is considered. However, in this case, since the width of the partition pattern of the donor substrate is too dense, there is a problem that stress occurs in the partition pattern during the substrate fabrication process or the joining / joining of the donor substrate and the device substrate, so that the partition pattern tends to collapse or defects occur. In addition, since a part of local film deflection may also be transferred, a part with a large film thickness nonuniformity may also occur in the device substrate.

Therefore, when using a donor substrate having a smooth surface, it is considered to design the insulating layer width of the device substrate to 30 µm or 40 µm (opening width ratio 70% or 60%). In these cases, if the partition pattern width of the donor substrate is designed to be 10 mu m, a device substrate with less film thickness nonuniformity can be produced by transferring to avoid local bias of the film generated in the range of 10 mu m from the partition wall. By the way, even if only a portion having a small non-uniformity is transferred by these methods, most of the transfer material remains in the vicinity of the insulating layer of the donor substrate, so that the material utilization efficiency is significantly lowered.

On the other hand, when a rough donor substrate is used, a local film thickness nonuniformity does not generate | occur | produce in the coating film of a donor substrate at first, and a device substrate excellent in film thickness uniformity can be produced regardless of the width of an insulating layer. In addition, there is an advantage that the material can be efficiently transferred. Therefore, the organic EL element whose insulating layer width of a device substrate is less than 40 micrometers, More preferably, it is 30 micrometers or less can be manufactured preferably.

In addition, the said dimension regarding the width of a subpixel is an example, and a phenomenon similar to the above arises as the width of an insulating layer changes, even if a subpixel width becomes larger or smaller than this. The subpixel width does not have an upper limit or a lower limit in particular, but if it is determined, a subpixel width, which is a design value of a general display panel, may be in the range of 30 µm or more and 1000 µm or less.

Increasing the aperture ratio by narrowing the width of the insulating layer of the organic EL element reduces the amount of current per unit area flowing when a constant voltage is applied to the element, thereby improving element durability. It is known empirically that the durability is inversely proportional to the 1.6 to 1.7 square of the current density. For example, increasing the aperture ratio from 60% to 70% improves the durability by about 30%. In addition, by suppressing the film thickness nonuniformity to ± 10%, the light emission luminance nonuniformity and the chromaticity nonuniformity in the pixel are reduced, so that the display quality can be improved and the bias of the current density distribution can be improved, so that the device life is long.

Fig. 14 shows a partition pattern sandwiched between the widths and the partition patterns 34 (in this example, 37R and 37G, 37G and 37B) of two or more different transfer materials 37 (three types of 37R, 37G and 37B in this example). By irradiating light-to-heat conversion layer 33 with light wider than the sum total of the width of two (34), two or more types of other transfer materials 37 (three types of 37R, 37G, 37B in this example) are collectively. It is a figure which shows one of the preferable embodiment to transfer. Here, an example of collectively transferring one set of 37R, 37G, and 37B as shown in FIGS. 2 and 3 is shown, but as is often seen in display applications, a set of transfer materials 37R, 37G, and 37B are arranged in such an arrangement. If k is repeated in the x direction and h times in the vertical y direction, for example, light is simultaneously applied to the transfer material 37R, 37G, 37B of m sets (m is an integer of 2 or more and k or less). By scanning the light in the y direction while irradiating, the transfer time can be shortened to about 1 / m. In the case of m = k, as shown in Fig. 15A, the entire transfer material 37 is collectively transferred in one scan by irradiating light to cover the entire width of the transfer region 38 of the donor substrate 30. It may be. In this arrangement, the positional adjustment of light irradiation with respect to the donor substrate 30 can be greatly reduced. As shown in Fig. 15B, when there are a plurality of transfer regions 38 on the substrate, it is also possible to collectively transfer them.

This batch transfer can shorten patterning time compared with the method of irradiating light sequentially to each transfer material 37R, 37G, 37B. Since the light is sufficiently absorbed by the light-to-heat conversion layer 33, each transfer material 37R, 37G, 37B having a different light absorption spectrum can be heated to the same temperature using the same light source, and the device is transmitted by the transmitted light. There is no fear that the substrate 10 may be heated. The presence of the partition pattern 34 prevents transfer of the transfer portions in which the adjacent transfer materials 37 are mixed with each other or shakes at the boundary position, so that batch transfer does not impair device performance.

In the example of the batch transfer, when the transfer materials 37R, 37G, 37B have different sublimation temperatures (temperature dependence of the vapor pressure), the batch transfer may be performed by one light irradiation in accordance with the transfer material having the highest sublimation temperature. On the contrary, for example, when the transfer material 37R has the lowest sublimation temperature, all of the transfer material 37R is partially transferred to 37G and 37B by one light irradiation, and again 37G and 37B are subjected to light irradiation. The rest may be transferred or may be divided into three or more transfers. Since the transfer time can be shortened by about 1 / m, the damage to the transfer material 37 can be further reduced by dividing the transfer time into m transfers. The optimal one can be selected from various transfer conditions while taking into account the time divided by the transfer process and the damage to the transfer material 37.

In addition, the batch transfer has another effect. Within the wide range of irradiation of light, heat diffusion in the horizontal direction, which has been a problem in laser transfer, does not occur, so that light can be irradiated for a relatively long time such as scanning the laser at a relatively low speed. Therefore, control of the highest achieved temperature of the transfer material 37 becomes easier, and fine patterning can be performed with high precision. Moreover, the fall of device performance can be suppressed to the minimum, without giving damage to the transfer material 37 at the time of transfer. The damage to the transfer material 37 is reduced, and the damage to the partition pattern 34 is also reduced, and deterioration is less likely to occur even when the partition pattern 34 is formed of an organic material. Therefore, the cost of the patterning which can reuse a donor substrate several times can be reduced. Moreover, since the position which irradiates light does not need to be strictly controlled by the conventional method, the mechanism of the apparatus which irradiates light can also be simplified.

Although a high intensity | strength is easily obtained as a light source of irradiation light, and the laser excellent in the shape control of irradiation light can be illustrated as a preferable light source, light sources, such as an infrared lamp, a tungsten lamp, a halogen lamp, a xenon lamp, and a flash lamp, can also be used. As the laser, known lasers such as semiconductor lasers, fiber lasers, YAG lasers, argon ion lasers, nitrogen lasers, excimer lasers and pulse lasers can be used.

The wavelength of the irradiation light is not particularly limited as long as the absorption in the irradiation atmosphere and the support 31 of the donor substrate is small and the absorption in the photothermal conversion layer 33 is performed efficiently. Therefore, not only the visible light region but also ultraviolet light to infrared light can be used. Considering the material of the preferable support body 31 of a donor substrate, 300 nm-5 micrometers can be illustrated as a preferable wavelength area, and 380 nm-2 micrometers can be illustrated as a more preferable wavelength area.

It does not specifically limit about the irradiation method and the scanning method of irradiation light, For example, the method currently disclosed by patent document 2 may be used.

The donor substrate for transcription | transfer which concerns on embodiment of this invention, the manufacturing method of the device using this, and the organic electroluminescent element were demonstrated above. Next, the Example which concerns on embodiment of this invention is described. The present invention can be variously modified within the scope of the matters described in the claims without being limited to those described in the above-described embodiments and the following examples.

Example

EXAMPLES Hereinafter, specific embodiments of the present invention will be described with reference to Examples, but the present invention is not limited thereto. In the following Examples and Comparative Examples, Ra and Sm on the surfaces of the support and the photothermal conversion layer were measured using a surface roughness measuring instrument (manufactured by TOKYO SEIMITSU CO., LTD.) Based on JIS B0601-1994 with a measurement length of 1.0. It was set as the 10-point average roughness obtained when measured by mm. The film thickness is measured by the optical interference type film thickness measuring device SP-700 (Toray Engineering Co., Ltd.) to measure the two-dimensional film thickness profile in the sub-pixel, and the emission luminance is measured by the FPD module inspection device (Otsuka Electronics Co., Ltd.). Measured using.

In addition, film thickness nonuniformity is the value computed by substituting the formula which becomes (maximum film thickness-minimum film thickness) / film thickness average value x100 in a subpixel, and light emission nonuniformity is the x direction and the y direction from the four edges of a subpixel. Luminance was measured at a spot diameter of 30 μm from a total point of 20 μm (four points in total) and a total of nine points of these four points in the x, y, and diagonal directions (five points in total). It is the value calculated by substituting into the formula which becomes the maximum luminance-minimum luminance) / luminance average value x100. The film thickness average value is a value obtained by dividing the total of the film thickness measurement values of all the measurement points in the subpixels by the measurement score of the film thickness. The luminance average value is a value obtained by dividing the total of nine luminance measurement values in the subpixels by nine (the number of luminance measurement points 48 in FIG. 13).

The durability was evaluated by continuously flowing a constant current of 10 mA / cm 2 and measuring the time (luminance half life) until the luminance was lowered by half from the initial luminance. In addition, the spot diameter was 5 mm so that the area | region containing the subpixel which measured the said luminescence brightness nonuniformity at least can be measured at this time.

Example 1

The donor substrate 30 was produced as follows. The support body 31 was etched with hydrofluoric acid using the alkali free glass substrate of 38x46 mm and thickness 0.7mm as the support body 31, and the surface of the side which forms the photothermal conversion layer 33 was roughened. Ra of the surface of the support body 31 was 30 nm, and Sm was 15 micrometers. After the washing / UV ozone treatment, a tantalum film having a thickness of 0.2 μm was formed as a photothermal conversion layer 33 by the sputtering method (gas type: Ar, gas pressure: 0.2 kPa, power: 1 kw). Ra of the surface of the photothermal conversion layer 33 was also 30 nm. Subsequently, after performing the UV ozone treatment of the photothermal conversion layer 33 similar to the above, the fluorine-type positive polyimide photosensitive coating agent was spin-coat-coated on it, and after exposure and prebaking, UV exposure, the exposure part was dissolved and removed by the developing solution. The patterned polyimide precursor film was baked at 350 ° C. for 10 minutes on a hot plate to form a polyimide partition pattern 34. The partition pattern 34 had a thickness of 7 µm and a width of 20 µm, and the cross section had a forward tapered shape. Inside the partition pattern 34, 768 openings exposing the photothermal conversion layer 33 having a width of 80 μm and a length of 280 μm were arranged at a pitch of 100 μm in the width direction and 200 at a pitch of 300 μm in the longitudinal direction. Next, a partition pattern 34 is formed so that a tantalum film having a thickness of 0.2 μm is formed on the entire surface of the donor substrate 30 by a 0.2 μm thickness sputtering method, so that the transfer material 37R and the transfer material 37G to be applied later are not mixed. The upper surface of the fluorine-based liquid repellent treatment was performed. The contact angle of the partition pattern 34 was about 60 degrees with respect to xylene. Each solution of transfer materials (37R, 37G) having a viscosity of about 0.75 mPa · s using xylene as a solvent was prepared. The solution forming the transfer material 37R was formed by dissolving a pyrene-based red host material RH-1 and a pyrromethene-based red dopant material RD-1 in xylene, respectively, by 0.5 wt% and 0.01 wt%, to form a transfer material 37G. The solution was obtained by dissolving pyrene-based green host material GH-1 and coumarin-based green dopant material (C545T) in xylene by 0.5 wt% and 0.04 wt%, respectively.

Among them, a 37G solution is first applied by the inkjet method to a section corresponding to G so that the transfer materials 37R and 37G on the donor substrate 30 become RGB repetitions so as to form an RGB pattern in which three RGB sections are used as a unit. Subsequently, the 37R solution was applied to the section corresponding to R by the inkjet method. In addition, since the blue light emitting layer functions as an electron transporting layer deposited on the device substrate later, the blue transfer material 37B was not applied here.

The planar photograph of the donor substrate after naturally drying xylene is shown to FIG. 16 (a). The thicknesses of the transfer materials 37R and 37G in the compartments were about 40 nm and about 30 nm, respectively, and local deviations of in-plane and in-zone transfer materials did not occur, resulting in a good film with very low film thickness nonuniformity.

Example 2

Inkjet coating was performed using the donor substrate 30 of the structure similar to Example 1 except Ra of the surface of the support body 31 and the photothermal conversion layer 33 being 150 nm. Sm of the surface of the support body 31 and the photothermal conversion layer 33 was 15 micrometers. The solution of the transfer material 37 was produced by dissolving 0.5 wt% of pyrene-based green host material GH-1 in cyclohexanone, and coating by the inkjet method was performed on all sections of the donor substrate 30.

The planar photograph of the donor substrate after naturally drying cyclohexanone is shown to FIG. 16 (b). The thickness of the transfer material 37 in the compartment is about 40 nm and adheres according to the unevenness of the surface of the light-to-heat conversion layer 33 (light color in Fig. 16B), but in-plane as in Example 1 And local deviation of the transfer material in the compartment did not occur, resulting in a good film with very little film thickness nonuniformity.

Example 3

Inkjet coating was performed by the method similar to Example 2 except having used the donor substrate 30 whose Ra of the surface of the support body 31 and the photothermal conversion layer 33 is 250 nm. Sm of the surface of the support body 31 and the photothermal conversion layer 33 was 15 micrometers.

The planar photograph of the donor substrate after naturally drying cyclohexanone is shown to FIG. 16 (c). The thickness of the transfer material 37 in the compartment is about 40 nm and adheres according to the unevenness of the surface of the light-to-heat conversion layer 33 (light and shade color in Fig. 16 (c)), but similarly to Examples 1 and 2 There was no local bias of the transfer material in the plane and in the compartment, resulting in a good film with very little film thickness nonuniformity.

Example 4

An organic EL device was produced using the donor substrate of Example 1.

The device substrate was produced as follows. An alkali-free glass substrate (sputtering film formation product, manufactured by GEOMATEC Co., Ltd.), on which the ITO transparent conductive film was deposited at 140 nm, was cut, and ITO was patterned into 768 stripe shapes at a 100 μm pitch by photolithography. Next, the polyimide precursor film patterned similarly to the donor substrate was baked at 300 degreeC for 10 minutes, and the polyimide insulating layer was formed. The height of this insulating layer was 1.8 micrometers, the width was 30 micrometers, and the cross section was a forward taper shape. Inside the pattern of the insulating layer, 200 openings exposing ITO having a width of 70 µm and a length of 250 µm were arranged at a pitch of 100 µm in the width direction and at a pitch of 300 µm in the longitudinal direction. The rectangular direction of the ITO stripe electrode was matched with the longitudinal direction of the insulating layer.

This substrate was subjected to UV ozone treatment, placed in a vacuum vapor deposition apparatus, and evacuated until the vacuum in the apparatus was 3 × 10 ⁻⁴ Pa or less. 50 nm of an amine compound and 10 nm of NPD were deposited on the whole surface of the light emitting area | region of this board | substrate by the resistance heating method.

Subsequently, the partition pattern of the donor substrate produced in Example 1 and the position of the insulating layer of the said device substrate were adjusted and opposed, it hold | maintained in the vacuum of 3x10 <^-4> Pa or less, and after sealing the outer peripheral part, it took out to air | atmosphere. . The transfer space partitioned by the insulating layer and the partition pattern was kept in vacuum. For transfer, light having a center wavelength of 940 nm and having an irradiation shape of a rectangle of 340 μm in width and 50 μm in length was used (light source: semiconductor laser diode).

The co-deposited film as the transfer material is irradiated with light from the glass substrate side of the donor substrate so as to coincide with the longitudinal direction of the partition pattern and the insulating layer and the longitudinal direction so that the transfer material and the partition pattern are simultaneously heated. It transferred onto the hole transport layer which is a base layer of. The laser intensity was 148 W / mm 2 and the scanning speed was 0.6 Hz. The light was repeatedly scanned so that the number of transfers was 24 times so that the light was transferred to the entire surface of the light emitting region while overlapping at a pitch of about 300 µm in the horizontal direction. As a result, the film thickness nonuniformity of the RG light emitting layer became ± 10% or less.

The device substrate after transfer of the RG light emitting layer was placed in the vacuum deposition apparatus again, and exhausted until the vacuum in the apparatus became 3 × 10 ⁻⁴ Pa or less. E-1 was vapor-deposited on 25 nm and the whole light emission area whole surface as the electron carrying layer by the resistance heating method. Next, 0.5 nm of lithium fluoride was deposited as a donor material (electron injection layer), and 100 nm of aluminum was further deposited as a 2nd electrode. At this time, aluminum was patterned into 200 stripe shapes at 300 탆 pitch by mask deposition to match the rectangular direction of the stripe electrode with the width direction of the insulating layer. Therefore, the fabricated organic EL device has a structure of a simple matrix display in which the first electrode made of ITO stripe and the second electrode made of aluminum stripe are orthogonal to each other, and the subpixels of R, G, and B are arranged at the intersections of both electrodes. The pixels constituted by 256 x 200 are arranged.

In each element produced using the donor substrate of Example 1, clear R, G, and B light emission were confirmed from each subpixel, and the emission luminance nonuniformity became each color ± 20% or less, and the color between the subpixels. No mixing was confirmed.

Example 5

An organic EL device was produced in the same manner as in Example 4 except that the width of the insulating layer of the device substrate of Example 4 was 25 μm. Then, as in Example 4, clear R, G, and B light emission were observed from each sub-pixel, respectively, and the film thickness unevenness was ± 10% or less for each color, and the luminance unevenness was less than ± 20% for each color. Color mixing was not confirmed. Moreover, compared with Example 4, durability improved 10% or more.

Example 6

An organic EL device was produced in the same manner as in Example 4 except that the width of the insulating layer of the device substrate of Example 4 was 35 μm. Then, as in Example 4, clear R, G, and B light emission were observed from each sub-pixel, respectively, and the film thickness unevenness was ± 10% or less for each color, and the luminance unevenness was less than ± 20% for each color. Color mixing was not confirmed. In addition, compared with Example 4, the durability was reduced by 10% or more.

Example 7

An organic EL device was produced in the same manner as in Example 4 except that the width of the insulating layer of the device substrate of Example 4 was 40 μm. Then, as in Example 4, clear R, G, and B light emission were observed from each sub-pixel, respectively, and the film thickness unevenness was ± 10% or less for each color, and the luminance unevenness was less than ± 20% for each color. Color mixing was not confirmed. In addition, compared with Example 4, the durability was reduced by 20% or more.

Example 8

Using the donor substrates produced in Examples 2 and 3, the device substrates produced by the same method as in Example 4 were transferred under the same transfer conditions as in Example 4. However, in this embodiment, the hole transport layer is not formed in the device substrate, and the pyrene-based green host material GH-1 formed in all sections of the donor substrate is transferred to the entire opening of the insulating layer on the device substrate, and The film was observed with an optical microscope. The transfer material adhered to the unevenness of the surface of the light-to-heat conversion layer 33 was homogenized to obtain a good film with very little film thickness nonuniformity in the plane and in the compartment.

Comparative Example 1

The donor substrate 30 was produced by the method similar to Example 1 except having not etched the support body 31 with hydrofluoric acid. The surface of the support body 31 and the photothermal conversion layer 33 was smooth.

When the inkjet coating is applied to the donor substrate 30 in the same manner as in Example 1 in the order of 37G solution and 37R solution, the solute is near the edge in the drying process of the solvent as shown in Fig. 16 (d). The film thickness of the central portion in the compartment is extremely thin due to the conveyed effect, and the 37G coating film is locally biased in the opposite direction to the 37R compartment by the effect of dry vapor of the 37R solution applied later. It became a film with a very large film thickness nonuniformity in which 90% of the solutes in total exist within micrometers.

Comparative Example 2

The organic EL element was produced by the method similar to Example 4 using the donor board | substrate with which the surface of the comparative example 1 was smooth, and the width of the insulating layer of Example 4 was a 30 micrometer device substrate.

Clear B light emission was observed from the B subpixel, but only R and G light emission was observed from the sublayers of R and G in the region of 5 占 퐉 from the insulating layer, and from the remaining areas of the R and G subpixels. Blue light emission of the electron transport layer was confirmed.

Comparative Example 3

The organic EL element was created by the method similar to Example 4 using the donor substrate whose surface of the comparative example 1 was smooth, and the device substrate whose width of the insulating layer of Example 5 is 25 micrometers.

Clear B light emission was observed from the subpixel of B, but R and G light emission were observed only from a slight area of 7.5 µm from the insulating layer from the subpixels of R and G, and the remaining areas of the subpixels of R and G were observed. From the above, only blue light emission of the electron transport layer could be confirmed.

Comparative Example 4

The organic EL element was created by the method similar to Example 4 using the donor substrate whose surface of the comparative example 1 was smooth, and the device substrate whose width | variety of the insulating layer of Example 6 is 35 micrometers.

Clear B light emission was observed from the B subpixel, but only R and G light emission was observed from the R and G subpixels only in a slight area of 2.5 µm from the insulating layer, and the remaining areas of the R and G subpixels. From the above, only blue light emission of the electron transport layer could be confirmed.

Comparative Example 5

The organic EL element was created by the method similar to Example 4 using the donor substrate whose surface of the comparative example 1 was smooth, and the device substrate whose width of the insulating layer of Example 7 is 40 micrometers.

Although clear B light emission was seen from the B subpixel, only blue light emission of the electron transport layer could be confirmed from the subpixels of R and G.

BACKGROUND OF THE INVENTION Field of the Invention The present invention is a thin film patterning technology constituting devices such as organic EL elements, organic TFTs, photoelectric conversion elements, various sensors, and the like. It can be used for the production of such.

10: organic EL element (device substrate) 11: support
12: TFT (including extraction electrode) 13: planarization layer
14: insulating layer 15: first electrode
16: hole transport layer 17: light emitting layer
18: electron transport layer 19: second electrode
20: device substrate 21: support
27: transfer film 30: donor substrate
31: support 33: photothermal conversion layer
34: compartment pattern 37: transfer material
38: transfer area 40: mask
44: width of the insulating layer 47: subpixel
48: luminance measurement point

Claims (10)

A transfer donor substrate having a substrate and a photothermal conversion layer formed on the substrate:
A donor substrate for transfer, characterized in that the surface of the light-to-heat conversion layer is a rough surface. The method of claim 1,
The arithmetic mean roughness of the surface of the said photothermal conversion layer is 30 nm or more, The transfer donor substrate characterized by the above-mentioned. The method according to claim 1 or 2,
The arithmetic mean roughness of the surface of the side in which the photothermal conversion layer of the said board | substrate is formed is 30 nm or more, The transfer donor substrate characterized by the above-mentioned. The method according to any one of claims 1 to 3,
Transfer surface of the donor substrate, characterized in that the average unevenness of the surface is 20㎛ or less. The method according to any one of claims 1 to 4,
A transfer donor substrate, characterized in that a partition pattern is formed on the upper surface of the light-to-heat conversion layer. A step of opposing the transfer donor substrate according to any one of claims 1 to 5 to a device substrate, and a step of transferring the transfer layer to the device substrate by irradiating light to the photothermal conversion layer. The manufacturing method of the device made into. In an organic EL device having an organic compound layer comprising a light emitting layer sandwiched between at least a pair of electrodes, wherein at least a portion of the organic compound layer is formed using a transfer method:
An organic EL device having a width of an insulating layer of a subpixel of less than 40 µm, and an uneven luminous intensity of light emitting regions in the subpixel being ± 20% or less. The method of claim 7, wherein
The width of the insulating layer of the said subpixel is 30 micrometers or less, The organic electroluminescent element characterized by the above-mentioned. In an organic EL device having an organic compound layer comprising a light emitting layer sandwiched between at least a pair of electrodes, wherein at least a portion of the organic compound layer is formed using a transfer method:
An organic EL device having a width of an insulating layer of a subpixel of less than 40 μm, and a film thickness nonuniformity of a light emitting region in the subpixel among the organic compound layers formed by the transfer method is ± 10% or less. The method of claim 9,
The width of the insulating layer of the subpixel is 30 µm or less.

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