Method for manufacturing organic el device, and application device

Abstract

To provide a technique advantageous for making a film thickness distribution uniform.SOLUTION: A method for manufacturing an organic EL device includes: a step of preparing a substrate having a principal surface including a plurality of first dot areas arranged in matrix and a plurality of second dot areas arranged in matrix and each having a size smaller than the first dot area; and an application step of applying first liquid to each of the plurality of first dot areas, applying second liquid to each of the plurality of second dot areas, and applying third liquid to spaces between the plurality of second dot areas.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to techniques for manufacturing organic electroluminescent devices. [Background technology]

[0002] When manufacturing an organic EL device equipped with a panel (organic EL panel) having an OLED (Organic Light Emitting Diode), which is an organic EL (Electro Luminescence) element, a method is known in which a solution film is applied to a desired location on a substrate using an inkjet device. A solution film is a film composed of a solution containing a solute and a solvent. A film (layer) is formed on the substrate by drying the substrate, i.e., by evaporating the solvent contained in the solution film applied on the substrate.

[0003] Patent Document 1 discloses a method for manufacturing an organic EL device, in which a substrate having a plurality of groove regions (subpixels) partitioned by banks is prepared, ink is applied to each groove region, and the substrate, i.e., the ink, is dried to form a pixel functional film in each groove region. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2015 / 166647 Summary of the Invention [Problem to be solved by the invention]

[0005] When two or more panels of different sizes are manufactured from one substrate, that is, when the substrate has a plurality of first dot regions and a plurality of second dot regions each smaller in size than the first dot regions, there is a risk of a deviation in the drying speed of the film in the first dot regions and the drying speed of the film in the second dot regions in the process of drying the substrate, which may result in a deviation in the film thickness distribution of the film formed in each dot region.

[0006] The present disclosure provides an advantageous technique for making the film thickness distribution uniform. [Means for solving the problem]

[0007] A first aspect of the present disclosure is a method for manufacturing an organic EL device, comprising: a step of preparing a substrate having a main surface including a plurality of first dot regions arranged in a matrix and a plurality of second dot regions arranged in a matrix, each of which is smaller in size than the first dot regions; and a coating step of applying a first liquid to each of the plurality of first dot regions, applying a second liquid to each of the plurality of second dot regions, and applying a third liquid between the plurality of second dot regions.

[0008] A second aspect of the present disclosure is a coating device comprising a liquid ejection unit, a substrate holding unit that holds a substrate having a main surface including a plurality of first dot regions arranged in a matrix and a plurality of second dot regions arranged in a matrix, each of which is smaller in size than the first dot regions, and a control unit that controls the liquid ejection unit, wherein the control unit controls the liquid ejection unit to apply a first liquid to each of the plurality of first dot regions, apply a second liquid to each of the plurality of second dot regions, and apply a third liquid between the plurality of second dot regions. Effect of the Invention

[0009] According to the present disclosure, an advantageous technique for achieving a uniform film thickness distribution is provided. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic diagram showing a configuration of a manufacturing system which is an example of a system according to a first embodiment. [Diagram 2] 1A is an explanatory view of a coating apparatus according to a first embodiment, and FIG. 1B is an explanatory view of the coating apparatus and a substrate according to the first embodiment. [Diagram 3]1A is an explanatory diagram of a portion of a first panel region according to the first embodiment, FIG. 1B is an explanatory diagram of a portion of a second panel region according to the first embodiment, and FIG. 1C is a cross-sectional view of a substrate according to the first embodiment. [Figure 4] 3(a) to 3(e) are diagrams illustrating a part of the manufacturing process of the organic EL device according to the first embodiment. [Diagram 5] 1A is an explanatory diagram of a part of a manufacturing process of the organic EL device according to the first embodiment, and FIG. [Figure 6] 10(a) is an explanatory view of a coating apparatus and a substrate according to a second embodiment, and (b) is an explanatory view of a part of a second panel region according to the second embodiment. [Figure 7] 10(a) to 10(d) are diagrams illustrating a part of a manufacturing process for an organic EL device according to a second embodiment. [Figure 8] 1(a) to 1(d) are explanatory views of a part of a manufacturing process for an organic EL device of a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the drawings. The following embodiments are illustrative of preferred configurations of the present disclosure, and for example, those skilled in the art can appropriately modify the detailed configurations without departing from the spirit of the present disclosure. In addition, in the drawings referred to in the following description of the embodiments, elements indicated by the same reference numbers have the same functions unless otherwise noted. In addition, these drawings are represented diagrammatically for convenience of illustration and explanation, and therefore shapes, sizes, arrangements, etc. may not strictly match between the drawings.

[0012] In the following embodiments, directions are indicated by an XYZ coordinate system, which is a Cartesian coordinate system. The X, Y, and Z directions are mutually orthogonal. In the XYZ coordinate system, the XY plane is a horizontal plane, and the XZ and YZ planes are vertical planes. The X and Y directions are horizontal directions. The negative direction of the Z axis is the vertical direction (gravity direction), in other words, the downward direction. Also, the positive direction of the Z axis is the upward direction.

[0013] In the following description, for example, the positive direction of the X-axis refers to the same direction as the X-axis arrow in the XYZ coordinate system, and the negative direction of the X-axis refers to the direction 180 degrees opposite to the direction of the X-axis arrow in the XYZ coordinate system. Also, when simply referring to the X-direction, it refers to the direction parallel to the X-axis, regardless of whether it is in the same direction as the X-axis arrow. The same applies to the Y-axis and Z-axis other than the X-axis.

[0014] In the following description, ink is a liquid (solution) containing a functional material for forming a functional film of an organic EL element.

[0015] [First embodiment] 1 is a schematic diagram showing the configuration of a manufacturing system 1000, which is an example of a system according to the first embodiment. The manufacturing system 1000 is a system that manufactures an organic EL device used in a display device.

[0016] The manufacturing system 1000 is configured to include, for example, a film forming apparatus that forms an organic film on a substrate 1. The organic film can be, for example, any one of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer of an organic electroluminescent device (OLED). A process for manufacturing an organic electroluminescent device can include a step of forming an organic film such as a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, or an electron injection layer on the substrate 1 by applying a solution containing a functional material.

[0017] The process of forming an organic film on the substrate 1 may include a coating process of coating a film-forming solution on the substrate 1 by, for example, an inkjet method, a drying process of drying the coated film-forming solution to form a dry film, and a baking process of baking the dry film. The film-forming solution may be a solution (ink) containing a solute and a solvent for forming an organic film. The solvent may have a property that evaporation is promoted in a reduced pressure environment lower than atmospheric pressure. Evaporation of the solvent may be promoted, for example, at a temperature higher than room temperature (25°C). Hereinafter, evaporating the solvent contained in the solution coated on the substrate 1 is also referred to as drying the substrate 1 or drying the solution coated on the substrate 1.

[0018] The manufacturing system 1000 includes a plurality of processing units that perform some processing on a substrate, and a transport mechanism 900 that transports a substrate between the plurality of processing units. Each processing unit may include a processing chamber. The manufacturing system 1000 includes a transport chamber 110 that is connected to each processing chamber of the plurality of processing units. The transport mechanism 900 may be disposed within the transport chamber 110. The transport chamber 110 may be disposed so as to be surrounded by processing chambers of the plurality of processing units. The manufacturing system 1000 may be a multi-chamber type article manufacturing system.

[0019] In one example, the multiple processing units include a coating unit 100 that coats the substrate 1 with a film forming solution by an inkjet method, and a drying unit 400 that dries the film forming solution coated on the substrate 1 by the coating unit 100. The multiple processing units may also include, for example, the coating unit 100, a load lock unit 200, an unload lock unit 300, a drying unit 400, a processing unit 500, a processing unit 600, a processing unit 700, and a processing unit 800.

[0020] The load lock unit 200 is used as an interface for transporting the substrate 1 from outside the manufacturing system 1000 to inside the manufacturing system 1000. The unload lock unit 300 is configured as an interface for transporting the substrate 1 after processing in the manufacturing system 1000 from the manufacturing system 1000 to the outside. The load lock unit 200 and the unload lock unit 300 may be configured as a single unit shared for loading and unloading.

[0021] The drying unit 400 is configured to dry the film forming solution applied onto the substrate 1 by the application unit 100 to form a dry film. The processing units 500 to 800 can be processing chambers for performing various processes such as cooling and alignment according to the characteristics of the apparatus. The number of processing units is not limited to the example shown in the figure, and can be increased or decreased.

[0022] The transport mechanism 900 is, for example, a transport robot. The transport robot is configured to hold a substrate, transport the substrate from the coating unit 100 to any one of the processing chambers, and transport the substrate from the processing chamber. For example, the transport robot is configured to transport the substrate from the coating unit 100 along a straight path, change the orientation of the substrate toward any one of the processing chambers by, for example, a rotational operation, and then transport the substrate straight into the processing chamber.

[0023] 1, a transfer chamber 111 may be provided between the coating unit 100 and the transfer chamber 110. In the first embodiment, the transfer chamber 111 may be configured to transfer the substrate 1 unloaded from the coating unit 100 in a straight line to the transfer mechanism 900 without changing the orientation of the substrate 1.

[0024] The manufacturing system 1000 may further include a control unit 120. The control unit 120 may be configured with hardware such as a field programmable gate array (FPGA). It may also be configured with a programmable logic device (PLD) or an application specific integrated circuit (ASIC). Alternatively, the control unit 120 may be configured with a general-purpose or dedicated computer in which a program (software) is embedded, or may be configured with a combination of all or part of the above.

[0025] The control unit 120 may include a CPU, an I / O port, and a computer-readable recording medium. As the computer-readable recording medium, a non-transitory recording medium that stores a processing program executed by the CPU, parameters necessary for executing the processing, and the like may be used. As the non-transitory recording medium, for example, a flexible disk, an optical disk, a magneto-optical disk, a magnetic tape, a USB memory, an SSD, and the like may be used. In addition, the information processing device may include a rewritable storage medium (such as a RAM) that provides a recording area necessary for processing such as calculations.

[0026] The control unit 120 controls the operation of each part of the manufacturing system 1000, including the coating unit 100. A computer-readable non-transitory recording medium included in the control unit 120 stores a program for the manufacturing system 1000 to manufacture a substrate for an organic EL device.

[0027] The coating device 150 includes the coating unit 100 and the control unit 120. The control unit 120 is an example of a control unit.

[0028] Fig. 2(a) is an explanatory diagram of a coating apparatus 150 according to the first embodiment. Fig. 2(b) is an explanatory diagram of the coating apparatus 150 and a substrate 1 according to the first embodiment. Note that part of the configuration of the coating apparatus 150 shown in Fig. 2(a) is omitted in Fig. 2(b). The coating unit 100 of the coating apparatus 150 includes a stage 130, which is an example of a substrate holding section capable of holding the substrate 1, and a liquid discharge section 140 that discharges liquid.

[0029] The substrate 1 is positioned and transported with high precision above the stage 130 by the transport mechanism 900 shown in FIG. 1. At this time, the substrate 1 is transported onto the stage 130 with the main surface 11 of the substrate 1 facing upward. The liquid discharge unit 140 includes a head 141 which is an example of a first head, and a head 142 which is an example of a second head. The head 141 is an inkjet head which discharges droplets of the supplied liquid from a nozzle. The head 142 is also an inkjet head which discharges droplets of the supplied liquid from a nozzle, and has the same basic configuration as the head 141.

[0030] Each of the heads 141, 142 is a line-type inkjet head extending in the Y direction, and has a plurality of nozzles arranged in the Y direction. Each of the heads 141, 142 can apply liquid to desired locations on the main surface 11 of the substrate 1 by scanning in the positive direction of the X axis, which is the scanning direction, and ejecting droplets. Note that each of the heads 141, 142 is not limited to being a line-type inkjet head, and may be configured to scan in the Y direction as well.

[0031] The liquid ejection unit 140 has a rail 145 and a driving device 147. The heads 141, 142 are supported by the rail 145 extending in the X direction, and are driven by the driving device 147 to move in the X direction along the rail 145. The control unit 120 controls the heads 141, 142 and the driving device 147. Note that, in the first embodiment, an example will be described in which the heads 141, 142 move relative to the substrate 1, but this is not limiting, and the stage 130 holding the substrate 1 may move relative to the heads 141, 142.

[0032] The substrate 1 has a base made of glass, a TFT element for driving the organic EL element, a lower electrode, and a bank. The TFT element, the lower electrode, and the bank are formed on the base. The bank is formed on the main surface 11 of the substrate 1 in the shape of the organic EL element, i.e., the shape of the dot region. The bank defines a recess capable of holding a solution in each dot region. The base of the substrate 1 also has a contact hole formed therein for connecting the lower electrode and the TFT element.

[0033] In the first embodiment, one picture element (1 pixel) is made up of dots (sub-pixels) of three colors, RGB. That is, one pixel is made up of three dots, i.e., three sub-pixels. R is red, G is green, and B is blue. Note that the number of sub-pixels included in one pixel is not limited to three.

[0034] 2(b), the main surface 11 of the substrate 1 has a dot region group 31 consisting of a plurality of dot regions 21 defined by banks, and a dot region group 32 consisting of a plurality of dot regions 22 defined by banks. The dot region group 31 is an example of a first group, and the dot region group 32 is an example of a second group.

[0035] In a plan view, i.e., when viewed in the Z direction, the dot region 22 has a smaller size (area) than the dot region 21. The dot region 21 is an example of a first dot region, and the dot region 22 is an example of a second dot region. Each of the dot regions 21 and 22 is a substantially rectangular region that is long in the X direction.

[0036] The dot region 21 is a region where a light-emitting portion that emits light of one of the colors RGB is formed. The dot region 22 is also a region where a light-emitting portion that emits light of one of the colors RGB is formed. In other words, the dot regions 21 and 22 are sub-pixel regions.

[0037] The multiple dot regions 21 are arranged in a matrix with gaps between them. In Fig. 2(b), the multiple dot regions 21 are arranged in the X and Y directions with gaps between them. The multiple dot regions 22 are arranged in a matrix with gaps between them. In Fig. 2(b), the multiple dot regions 22 are arranged in the X and Y directions with gaps between them.

[0038] The dot region group 31 is included in a panel region 41 shown by a dashed line. The panel region 41 is a region that will become an organic EL panel. The dot region group 32 is included in a panel region 42 shown by a dashed line. The panel region 42 is a region that will become an organic EL panel. The panel region 42 is smaller in size (area) than the panel region 41. The dot region group 31 is an example of a first region group, and the dot region group 32 is an example of a second region group. The panel region 41 is an example of a first panel region, and the panel region 42 is an example of a second panel region. The substrate 1 will later be cut into each panel.

[0039] The substrate 1 includes a plurality of panel regions 41 and a plurality of panel regions 42. That is, the substrate 1 includes a plurality of dot region groups 31 and a plurality of dot region groups 32. The panel region 41 is a region that includes the dot region group 31. The panel region 42 is a region that includes the dot region group 32.

[0040] The organic EL panel formed by the panel region 41 is used for displays such as large TVs, and the organic EL panel formed by the panel region 42 is used for displays such as laptop PCs. The smaller the area of ​​the panel region, the higher the resolution (dpi), i.e., the more pixels per unit area. Therefore, the resolution of the organic EL panel formed by the panel region 42 is higher than that of the organic EL panel formed by the panel region 41.

[0041] A solution (ink) is applied to each of the dot regions 21 and 22, and a functional film such as an organic film is formed in each of the dot regions 21 and 22 by evaporating a solvent contained in the applied ink.

[0042] The ink, which is a liquid, is composed of a solution containing a solute (functional material) and a solvent for forming an organic film, for example. The solvent contained in the ink preferably has a property that evaporation is promoted in a reduced pressure environment lower than atmospheric pressure. The evaporation of the solvent is preferably promoted, for example, at a temperature higher than room temperature (25°C). The solute is a functional material for forming an OLED.

[0043] The solvent is preferably an organic solvent. The solvent contains at least one kind of organic solvent. Examples of the organic solvent include N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, diethylene glycol monomethyl ether, cyclohexanone, N,N-dimethylisobutyramide, N-methylformamide, N-methylacetamide, N-diethylformamide, cyclohexanol, ethylene glycol, ethylene glycol diglycidyl ether, 1,3-octylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, 1,3-butanediol, 1,4-butanediol, and the like. Examples of the monomer units include propylene glycol, hexylene glycol, propylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether, diacetone alcohol, γ-butyrolactone, ethyl lactate, N-hexyl acetate, and ethyl cellosolve acetate.

[0044] The organic film is an organic layer, for example, any one of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer of an OLED. The manufacture of an organic EL device includes a process of forming each of the organic films, the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer, and the electron injection layer, at a predetermined position on a substrate 1.

[0045] Figures 8(a) to 8(d) are explanatory diagrams of a part of the manufacturing process of an organic EL device of a comparative example, and each of Figures 8(a) to 8(d) shows a schematic cross section of a substrate 1X of the comparative example.

[0046] As shown in Fig. 8(a), a substrate 1X is prepared having a panel region 41X including a plurality of dot regions 21X and a panel region 42X including a plurality of dot regions 22X. In plan view, i.e., when viewed in the Z direction, the panel region 42X is smaller in size than the panel region 41X, and the dot regions 22X are smaller in size than the dot regions 21X. Furthermore, the pitch in the X direction of the dot regions 22X is smaller than the pitch in the X direction of the dot regions 21X, and the pitch in the Y direction of the dot regions 22X is smaller than the pitch in the X direction of the dot regions 21X. The dot regions 21X are defined by banks 81X, and the dot regions 22X are defined by banks 82X.

[0047] 8(b), a first amount of ink S1X is applied to a dot region 21X by a head 4X, and a second amount of ink S2X, which is less than the first amount, is applied to a dot region 22X by a head 4X. Note that the ink S2X is the same type of solution as the ink S1X.

[0048] Next, the substrate 1X coated with the inks S1X and S2X is transported to a drying unit, where the substrate 1X is dried. Here, the surface area of ​​the ink S1X in the panel region 41X is larger than the surface area of ​​the ink S2X in the panel region 42X. Therefore, in this drying process, as shown in FIG. 8(c), the solvent vapor pressure above the panel region 41X is greater than the solvent vapor pressure above the panel region 42X. As a result, the panel region 42X, which has a lower solvent vapor pressure than the panel region 41X, dries faster than the panel region 41X.

[0049] When there is a difference in the timing at which the drying ends, the solvent moves from the slower drying speed to the faster drying speed in each dot region 21X, 22X. As a result, as shown in FIG. 8(d), the dried films F1X, F2X are formed with their upper surfaces inclined relative to the horizontal plane, resulting in uneven thickness of the dried films F1X, F2X.

[0050] Therefore, in the first embodiment, the amount of ink applied to the panel region 42 in the application process is adjusted so that the pressure above the panel region 41 and the pressure above the panel region 42 in the drying process are uniform, i.e., so that the pressure distribution in the space above the substrate 1 is uniform.

[0051] Fig. 3(a) is an explanatory diagram of a portion of a panel region 41 according to the first embodiment. Fig. 3(b) is an explanatory diagram of a portion of a panel region 42 according to the first embodiment. Fig. 3(c) is a cross-sectional view of a substrate 1 according to the first embodiment. Fig. 3(c) is a schematic diagram of a cross-section of the substrate 1 taken along line AA shown in Fig. 2(b).

[0052] The size of dot region 22, i.e., the area A2 of dot region 22 when viewed in the Z direction, is smaller than the size of dot region 21, i.e., the area A1 of dot region 21 when viewed in the Z direction. Furthermore, the pitch P2X of dot region 22 in the X direction is smaller than the pitch P1X of dot region 21 in the X direction, and the pitch P2Y of dot region 22 in the Y direction is smaller than the pitch P1Y of dot region 21 in the Y direction. Dot region 21 is a recess defined by bank 81, and dot region 22 is a recess defined by bank 82.

[0053] In the first embodiment, the main surface 11 of the substrate 1 has recesses 50 capable of holding liquid, which are formed between the multiple dot regions 22. The recesses 50 are formed outside the dot regions 22 so as not to overlap with the dot regions 22. The recesses 50 are formed to avoid the contact holes 70 formed between the multiple dot regions 22, as shown in FIG. 3(b).

[0054] In the first embodiment, a plurality of contact holes 70 are formed in each of the panel regions 41 and 42. In the panel region 41, the plurality of contact holes 70 are formed between the plurality of dot regions 21, avoiding the plurality of dot regions 21. In the panel region 42, the plurality of contact holes 70 are formed between the plurality of dot regions 22, avoiding the plurality of dot regions 22.

[0055] The recess 50 is disposed between four dot regions 22 arranged in two rows and two columns. That is, the recess 50 is disposed at the center position of the smallest rectangular region that is sandwiched between the four dot regions 22 and surrounds the four dot regions 22. The recess 50 has, for example, a circular shape when viewed in a plan view, that is, when viewed in the Z direction. In the example of FIG. 3(b), the recess 50 is disposed between two contact holes 70 in the Y direction. The recess 50 is defined by a bank 83 as shown in FIG. 3(c).

[0056] In the first embodiment, as shown in FIG. 2(b), the main surface 11 of the substrate 1 is outside the plurality of panel regions 41 and the plurality of panel regions 42 and has one recess 60 as at least one recess formed on the outer periphery of the main surface 11. In the example of FIG. 2(b), the recess 60 is a continuous groove portion formed along the outer periphery of the main surface 11, but is not limited thereto. For example, as the at least one recess, a plurality of recesses may be arranged at intervals along the outer periphery of the main surface 11. The recess 60 is defined by a bank 84 as shown in FIG. 3(c). Note that the recess 50 does not exist on the line AA shown in FIG. 2(b), but the recess 50 is illustrated in FIG. 3(c) for convenience of explanation.

[0057] In order to adjust the amount of the solvent in the panel region 41, as shown in Fig. 3(a), recesses 61 capable of holding liquid may be formed between the multiple dot regions 21. As shown in Fig. 3(c), the recesses 61 are defined by banks 85.

[0058] Figures 4(a) to 4(e) and 5(a) are diagrams illustrating a part of the manufacturing process of the organic EL device according to the first embodiment. Figures 4(a) to 4(e) show schematic cross sections of the substrate 1.

[0059] First, the substrate 1 shown in FIG. 4(a) is prepared, and the substrate 1 is transported inside the coating chamber of the coating unit 100 shown in FIG. 1. Next, the control unit 120 scans the head 142 as shown in FIG. 4(b), ejects the liquid S3 and the liquid S4 from the head 142, and applies the liquid S3 to the recess 50 and the liquid S4 to the recess 60. That is, the liquid S3 is applied between the multiple dot regions 22, and the liquid S4 is applied to the outer periphery of the main surface 11 of the substrate 1. In the first embodiment, the liquid S3 is applied between four dot regions 22 arranged in two rows and two columns. At that time, by applying the liquid S3 to the recess 50, the liquid S3 is held in the recess 50, and the liquid S3 is reduced from spreading outside the recess 50, and by applying the liquid S4 to the recess 60, the liquid S4 is held in the recess 60, and the liquid S4 is reduced from spreading outside the recess 60.

[0060] As described above, the liquid S3 and the liquid S4 are applied to the recesses 50 and the recesses 60 of the substrate 1 using the head 142. The liquid S3 is an example of a third liquid, and the liquid S4 is an example of a fourth liquid.

[0061] The liquid S4 has the same components and composition as the liquid S3. The recesses 50 and 60 are dummy regions that are different from the dot regions 21 and 22 in which pixel dots are formed.

[0062] In addition, when the components of liquid S4 are made different from the components of liquid S3, two heads may be prepared instead of one head 142, and one of the two heads may apply liquid S3 to each recess 50 of substrate 1, and the other head may apply liquid S4 to each recess 60 of substrate 1.

[0063] Next, as shown in Fig. 4(c), the control unit 120 scans the head 141 to eject the ink S1 and the ink S2 from the head 141, applying the ink S1 to the dot region 21 and applying the ink S2 to the dot region 22. The ink S1 is an example of a first liquid, and the ink S2 is an example of a second liquid. A first amount of ink S1 is applied to the dot region 21, and a second amount of ink S2, which is less than the first amount, is applied to the dot region 22.

[0064] Each of the inks S1 and S2 is a solution (liquid) for forming a functional film of an organic EL element, and is a solution (liquid) containing a functional material. In the first embodiment, the ink S2 is a liquid having the same components and composition as the ink S1. Note that the composition (amount of components) of the ink S2 may be slightly different from that of the ink S1.

[0065] In addition, if the components of ink S2 are made different from the components of ink S1, two heads can be prepared instead of one head 141, and one of the two heads can be used to apply ink S1 to each dot area 21 of substrate 1, and the other head can be used to apply ink S2 to each dot area 22 of substrate 1.

[0066] On the other hand, since the recesses 50, 60 to which the liquids S3, S4 are applied are dummy regions that do not become pixels, it is preferable that the liquids S3, S4 disappear from the substrate 1 by evaporation in the drying process. Therefore, it is preferable that the liquids S3, S4 are liquids that do not contain functional materials. For example, it is preferable that the liquids S3, S4 contain at least one of the organic solvents described above. This can prevent residues from remaining in the recesses 50, 60 after the substrate 1 is dried.

[0067] As described above, the area of ​​panel region 42 is smaller than the area of ​​panel region 41, and the amount of ink S2 per unit area in panel region 42 is smaller than the amount of ink S1 per unit area in panel region 41. In the first embodiment, by applying liquid S3 inside panel region 42, it is possible to reduce the difference between the amount of liquid per unit area in panel region 41 and the amount of liquid per unit area in panel region 42, and the liquid is applied uniformly over main surface 11 of substrate 1.

[0068] From the viewpoint of achieving a uniform pressure distribution on the substrate 1 due to evaporation of the solvent in the subsequent drying step, it is preferable that the liquids S3 and S4 are liquids having the same components and composition as the solvent contained in the inks S1 and S2. Furthermore, this can prevent any residue from remaining in the recesses 50 and 60 after the substrate 1 is dried.

[0069] In the first embodiment, the recesses 50 and 60 are formed to avoid the contact hole 70. That is, the liquids S3 and S4 are applied to the substrate 1 to avoid the contact hole 70. Therefore, the liquids S3 and S4 are not limited to solvents that do not contain functional materials, and the liquid S3 or the liquid S4 may be a liquid having the same components as the ink S1 or the ink S2, although an unnecessary functional film is formed in the recesses 50 or the recesses 60.

[0070] Furthermore, whether or not to apply the liquid S4 to the recessed portion 60 may be determined depending on the difference between the amount of ink applied to the panel area 41 and the amount of ink applied to the panel area .

[0071] As described above, in the application process shown in Figures 4(a) to 4(c), the control unit 120 controls the heads 141, 142 and driving device 147 of the liquid ejection section 140 to apply ink S1 to each of the multiple dot regions 21 included in each dot region group 31, apply ink S2 to each of the multiple dot regions 22 included in each dot region group 32, apply liquid S3 to each of the multiple recesses 50 included in each panel region 42, and apply liquid S4 to the recesses 60.

[0072] In the first embodiment, in the coating process, the control unit 120 controls the liquid ejection unit 140 to coat the liquids S3 and S4 on the recesses 50 and 60 of the substrate 1 before coating the inks S1 and S2 on the dot regions 21 and 22 of the substrate 1. As a result, the solvent evaporates from the liquids S3 and S4, creating a solvent atmosphere above the substrate 1, and the evaporation of the solvent contained in the inks S1 and S2 to be applied later during the coating process and in the period between the coating process and the drying process is reduced. In particular, coating the liquid S4 first on the recesses 60 located on the outer periphery of the main surface 11 of the substrate 1 is suitable for creating a solvent atmosphere above the main surface 11 of the substrate 1. As a result, the amount of evaporation of the solvent of the inks S1 and S2 applied to the dot regions 21 and 22 during the coating process and in the period between the coating process and the drying process can be reduced. Therefore, the pressure distribution on the substrate 1 can be made more stable and uniform in the subsequent drying process, the difference in drying speed can be reduced, and the thickness of the film can be made uniform, i.e., the variation in the thickness of the film can be reduced.

[0073] Next, the control unit 120 controls the transport mechanism 900 to transport the substrate 1 coated with the liquid out of the coating unit 100 and into the drying unit 400. Then, the control unit 120 controls the drying unit 400 to dry the substrate 1 as shown in FIG. 4(d), that is, to evaporate the liquid (solvent) coated on the substrate 1. As a result, as shown in FIG. 4(e), dried films F1 and F2 are formed of the functional material contained in the inks S1 and S2 in the dot regions 21 and 22. The substrate 1 coated with the inks S1 and S2 and the liquids S3 and S4 is dried by the drying process shown in FIG. 4(d) and FIG. 4(e) above.

[0074] 4(d), in the first embodiment, liquid S3 is applied to panel region 42 so as to reduce the difference between the amount of solvent in panel region 41 and the amount of solvent in panel region 42, and therefore the solvent vapor pressure above substrate 1, i.e., the pressure distribution, can be made uniform. This makes it possible to reduce the difference in drying speed and make the film thickness uniform, i.e., reduce the variation in film thickness.

[0075] Furthermore, the solvent contained in the ink in the dot regions near the periphery of main surface 11 of substrate 1 evaporates more easily than the solvent contained in the ink in the dot regions in the center of main surface 11. Therefore, in order to prevent the ink in the dot regions near the periphery of main surface 11 of substrate 1 from drying before the ink in the dot region in the center, it is preferable to apply liquid S4 to recesses 60.

[0076] After the drying step, the substrate is baked in various atmospheres, at various temperatures, and for various times depending on the film properties, whereby functional films for the organic EL elements are formed in the dot regions 21 and 22.

[0077] When an organic EL element is manufactured, the above-mentioned coating step, drying step, and baking step are repeated a required number of times to form a plurality of layers of the organic EL element, such as a hole injection layer, a hole transport layer, and a light-emitting layer.

[0078] After the light-emitting layer is formed, various layers such as an electron injection layer, an upper electrode, and an optical distance adjustment layer are formed in a deposition process to form a sealing film or a sealing structure. Then, in a cutting process, the substrate 1 is cut along the dashed lines indicating the panel regions 41 and 42 shown in Fig. 2(b) to obtain a plurality of panels P1 and a plurality of panels P2 as shown in Fig. 5(a).

[0079] In this manner, a plurality of panels P1 and a plurality of panels P2 are manufactured from one substrate 1. The panels P1 and P2 are organic EL panels having different sizes (areas). That is, the panel P2 is an organic EL panel having a smaller size (area) than the panel P1. The organic EL panels are used to manufacture organic EL devices such as displays.

[0080] Here, the calculation of the ink amount for each panel will be described. The ink amount per unit area of ​​each panel can be written as follows. Note that in the following description of the ink amount, ink includes liquids that do not contain functional materials. Ink amount per unit area = (ink amount in dot area + ink amount in recessed area) / panel area

[0081] In the dot areas, the amount of ink required for each of the R, G, and B colors generally differs, but since the intervals between the dot areas are very close, at several tens to several hundred μm, there is no significant difference in the solvent atmosphere between the R, G, and B dot areas.

[0082] Therefore, the amount of ink required for one pixel can be calculated by adding up the amount of ink for each of the R, G, and B colors. This total amount of ink can be added to the amount of ink in the recesses, for example, to determine the total amount of ink per panel, and then divided by the panel area to calculate the amount of ink per unit area of ​​each panel.

[0083] For example, in a large panel such as a large television, no ink is required in areas other than the dot areas 21, while in a small panel such as a laptop PC, the amount of ink applied to the recesses 50 between multiple dot areas 22 is adjusted.

[0084] According to this method, when a small panel with a small amount of ink per unit area is manufactured in combination with a large panel from one substrate 1, the difference in drying speed between the panels can be reduced by applying ink or solvent to the recessed portion 50 of the small panel with the small amount of ink. This reduces the variation in the thickness of the film formed, for example, the film shape of the light-emitting layer. In other words, it is possible to reduce the unevenness in brightness caused by the film shape variation of the light-emitting layer, and to manufacture an organic EL device with the desired light-emitting characteristics. In addition, since the thickness of the film can be made uniform, it is possible to reduce localized concentration of current and extend the life of the pixels (dots).

[0085] As described above, according to the first embodiment, the film thickness distribution of the film formed in the dot regions 21 and 22 can be made uniform.

[0086] [Modification 1 of the first embodiment] FIG. 5(b) is an explanatory diagram of a part of the panel region 42 of the first modification. As in the first embodiment, the liquid S3 may be a liquid that does not contain a functional material, preferably a liquid that has the same components as the solvent contained in the ink S2. The liquid S3 disappears from the substrate 1 by evaporating in the drying process, so that no residue of the liquid S3 remains on the substrate 1. For this reason, as shown in FIG. 5(b), instead of the recess 50, a recess 51 may be formed in the region including the contact hole 70. In this way, it is not necessary to avoid the contact hole 70, and the recess 51 larger than the recess 50 can be set. In the example of FIG. 5(b), the recess 51 is an elliptical region that is longer in the Y direction than two or more dot regions 22. That is, even if the liquid S3 is applied on the contact hole 70, no residue of the liquid S3 remains, so that the degree of freedom in adjusting the amount of solvent in the panel region 42 is increased without affecting the electrical characteristics of the contact hole 70.

[0087] In the first embodiment, a case has been described in which panels P1 and P2 of two different sizes are manufactured from a single substrate 1; however, this is not limited to this, and panels of three or more different sizes may be manufactured from a single substrate.

[0088] In the first embodiment, the liquid S3 is a liquid different from the ink S2, but the present invention is not limited to this, and the liquid S3 may be a liquid having the same components as the ink S2. In this case, one of the heads 141 and 142 may be omitted, and one head may perform two scans.

[0089] [Second embodiment] A second embodiment of the present disclosure will be described. In the following, elements with the same reference symbols as those in the first embodiment will have substantially the same configurations and functions as those described in the first embodiment unless otherwise specified, and differences from the first embodiment will be mainly described.

[0090] Fig. 6(a) is an explanatory diagram of a coating apparatus 150A and a substrate 1 according to the second embodiment. The coating apparatus 150A includes a stage 130, a liquid discharger 140A, and the control unit 120 shown in Fig. 1. In the coating apparatus 150A of the second embodiment, the liquid discharger 140 in the coating apparatus 150 of the first embodiment is replaced with the liquid discharger 140A.

[0091] The ink S1, the ink S2, the liquid S3, and the liquid S4 are liquids having the same components and the same composition. The liquid ejection section 140 of the first embodiment includes two heads 141 and 142, but the liquid ejection section 140A of the second embodiment includes one head 14. That is, the liquid ejection section 140A has substantially the same configuration as the liquid ejection section 140 from which one of the two heads 141 and 142 has been omitted. The liquid ejection section 140A includes a rail (not shown) and a drive device (not shown).

[0092] 6(b) is an explanatory diagram of a part of the panel region 42 according to the second embodiment. The recesses 50 are formed so as to avoid the contact holes 70 formed between the multiple dot regions 22.

[0093] Figures 7(a) to 7(d) are explanatory diagrams of a part of the manufacturing process of the organic EL device according to the second embodiment, each of which illustrates a cross section of the substrate 1 taken along the line BB shown in Figure 6(a).

[0094] First, as shown in FIG. 7(a), the substrate 1 is prepared and placed in the coating chamber of the coating device 150A. Next, as shown in FIG. 7(b), the control unit 120 scans the head 14 to eject the ink S1, the ink S2, the liquid S3, and the liquid S4 from the head 14, and applies the ink S1 to the dot region 21, the ink S2 to the dot region 22, the liquid S3 to the recess 50, and the liquid S4 to the recess 60. In the second embodiment, since the ink S1, the ink S2, the liquid S3, and the liquid S4 have the same components, it is sufficient to scan the head 14 once in the positive direction of the X-axis. The drying process shown in FIG. 7(c) and FIG. 7(d) is the same as the drying process shown in FIG. 4(d) and FIG. 4(e) of the first embodiment, and therefore a description thereof will be omitted.

[0095] As described above, according to the second embodiment, similarly to the first embodiment, the film thickness distribution of the film formed in the dot regions 21 and 22 can be made uniform.

[0096] The present disclosure is not limited to the above-described embodiments, and many modifications of the embodiments are possible within the technical concept of the present disclosure. Furthermore, the effects described in the present embodiment are merely a list of the most preferable effects resulting from the embodiments of the present disclosure, and the effects of the embodiments of the present disclosure are not limited to those described in the present embodiment.

[0097] The disclosure of the above embodiments includes the following sections.

[0098] (Section 1) preparing a substrate having a main surface including a plurality of first dot regions arranged in a matrix and a plurality of second dot regions arranged in a matrix, each of the second dot regions being smaller in size than the first dot regions; a coating step of coating a first liquid on each of the plurality of first dot regions, coating a second liquid on each of the plurality of second dot regions, and coating a third liquid between the plurality of second dot regions, The present invention relates to a method for producing an organic electroluminescence device.

[0099] (Section 2) The method further includes a drying step of drying the substrate on which the first liquid, the second liquid, and the third liquid have been applied. 2. The method for producing an organic EL device according to item 1,

[0100] (Section 3) a cutting step of cutting the substrate to obtain a first panel including a first group including the plurality of first dot regions and a second panel including a second group including the plurality of second dot regions. 3. The method for producing an organic EL device according to item 2,

[0101] (Section 4) The substrate has a plurality of the first groups and a plurality of the second groups, In the cutting step, the substrate is cut to obtain a plurality of the first panels and a plurality of the second panels. 4. The method for producing an organic EL device according to item 3,

[0102] (Section 5) The second panel is smaller in size than the first panel. Item 5. The method for producing an organic EL device according to item 3 or 4,

[0103] (Section 6) the pitch of the second dots is smaller than the pitch of the first dots; 6. The method for producing an organic EL device according to any one of items 1 to 5,

[0104] (Section 7) The second liquid is a liquid having the same composition as the first liquid. 7. The method for producing an organic EL device according to any one of items 1 to 6,

[0105] (Section 8) The first liquid is a solution containing a functional material. 8. The method for producing an organic EL device according to any one of items 1 to 7,

[0106] (Section 9) The third liquid is a liquid having the same composition as the second liquid. 9. The method for producing an organic EL device according to any one of items 1 to 8,

[0107] (Section 10) The third liquid is a liquid that does not contain a functional material. 9. The method for producing an organic EL device according to any one of items 1 to 8,

[0108] (Section 11) The third liquid is a liquid having the same components as the solvent contained in the second liquid. 11. The method for producing an organic EL device according to item 10,

[0109] (Section 12) the first liquid and the second liquid are applied using a first head, The third liquid is applied using a second head different from the first head. 12. The method for producing an organic EL device according to item 10 or 11,

[0110] (Section 13) The first liquid, the second liquid, and the third liquid are applied using a head. 10. The method for producing an organic EL device according to item 9,

[0111] (Section 14) In the application step, the third liquid is applied before the first liquid and the second liquid are applied. Item 14. The method for producing an organic EL device according to any one of items 1 to 13,

[0112] (Section 15) the substrate is disposed between the second dot regions and has a recess for holding the applied third liquid; Item 15. The method for producing an organic EL device according to any one of items 1 to 14,

[0113] (Section 16) the recess is defined by a bank; Item 16. The method for producing an organic EL device according to item 15,

[0114] (Section 17) In the applying step, the third liquid is applied between four second dot regions arranged in two rows and two columns among the plurality of second dot regions. Item 17. The method for producing an organic EL device according to any one of items 1 to 16,

[0115] (Section 18) The third liquid is applied to the substrate while avoiding contact holes. Item 18. The method for producing an organic EL device according to any one of items 1 to 17,

[0116] (Section 19) The third liquid is applied to an area including a contact hole. Item 18. The method for producing an organic EL device according to any one of items 1 to 17,

[0117] (Section 20) In the coating step, a fourth liquid is coated on an outer periphery of the main surface of the substrate. 20. The method for producing an organic EL device according to any one of items 1 to 19,

[0118] (Section 21) The fourth liquid is a liquid having the same composition as the third liquid. 21. The method for producing an organic EL device according to item 20,

[0119] (Section 22) A liquid ejection unit; a substrate holding section that holds a substrate having a main surface including a plurality of first dot regions arranged in a matrix and a plurality of second dot regions arranged in a matrix, each of the first dot regions being smaller in size than the first dot regions; A control unit that controls the liquid ejection unit, the control unit controls the liquid ejection unit to apply a first liquid to each of the plurality of first dot regions, apply a second liquid to each of the plurality of second dot regions, and apply a third liquid between the plurality of second dot regions; A coating device comprising:

[0120] (Section 23) the first liquid and the second liquid are liquids containing a functional material, the third liquid is a liquid that does not contain a functional material, The liquid ejection unit includes: a first head that ejects the first liquid and the second liquid; a second head that ejects the third liquid; 23. The coating device according to item 22,

[0121] (Section 24) the first liquid, the second liquid, and the third liquid are liquids containing a functional material, the liquid ejection unit includes a head that ejects the first liquid, the second liquid, and the third liquid, 23. The coating device according to item 22, [Explanation of symbols]

[0122] S1...ink (first liquid), S2...ink (second liquid), S3...liquid (third liquid), S4...liquid (fourth liquid), 1...substrate, 11...main surface, 21...dot region (first dot region), 22...dot region (second dot region), 31...dot region group (first group), 32...dot region group (second group), 41...panel region (first panel region), 42...panel region (second panel region), 50...recess, 120...control unit (control section), 140...liquid ejection section

Claims

1. A step of preparing a substrate having a main surface that includes a plurality of first dot regions arranged in a matrix, and a plurality of second dot regions arranged in a matrix, each smaller in size than the first dot region, The process includes a coating step of applying a first liquid to each of the plurality of first dot regions, applying a second liquid to each of the plurality of second dot regions, and applying a third liquid between the plurality of second dot regions. A method for manufacturing an organic EL device characterized by the following:

2. The method further comprises a drying step of drying the substrate to which the first liquid, the second liquid, and the third liquid have been applied. A method for manufacturing an organic EL device according to claim 1, characterized in that it is described above.

3. The process further includes a cutting step of cutting the substrate to obtain a first panel encompassing a first group including a plurality of first dot regions, and a second panel encompassing a second group including a plurality of second dot regions. A method for manufacturing an organic EL device according to claim 2, characterized in that it is a method for manufacturing an organic EL device.

4. The substrate has a plurality of first groups and a plurality of second groups, In the cutting step, the substrate is cut to obtain a plurality of first panels and a plurality of second panels. A method for manufacturing an organic EL device according to claim 3, characterized in that it is a method for manufacturing an organic EL device.

5. The second panel is smaller in size than the first panel. A method for manufacturing an organic EL device according to claim 3, characterized in that it is a method for manufacturing an organic EL device.

6. The pitch of the plurality of second dot regions is smaller than the pitch of the plurality of first dot regions. A method for manufacturing an organic EL device according to any one of claims 1 to 5.

7. The second liquid is a liquid with the same components as the first liquid. A method for manufacturing an organic EL device according to any one of claims 1 to 5.

8. The first liquid is a solution containing a functional material. A method for manufacturing an organic EL device according to any one of claims 1 to 5.

9. The third liquid is a liquid with the same components as the second liquid. A method for manufacturing an organic EL device according to any one of claims 1 to 5.

10. The third liquid mentioned above is a liquid that does not contain functional materials. A method for manufacturing an organic EL device according to any one of claims 1 to 5.

11. The third liquid is a liquid having the same components as the solvent contained in the second liquid. A method for manufacturing an organic EL device according to claim 10, characterized in that it is a method for manufacturing an organic EL device.

12. The first liquid and the second liquid are applied using the first head. The third liquid is applied using a second head different from the first head. A method for manufacturing an organic EL device according to claim 10, characterized in that it is a method for manufacturing an organic EL device.

13. The first liquid, the second liquid, and the third liquid are applied using a head. A method for manufacturing an organic EL device according to claim 9.

14. In the coating step, the third liquid is applied before the first and second liquids are applied. A method for manufacturing an organic EL device according to any one of claims 1 to 5.

15. The substrate is positioned between the plurality of second dot regions and has recesses that hold the coated third liquid, A method for manufacturing an organic EL device according to any one of claims 1 to 5.

16. The recess is defined by the bank. A method for manufacturing an organic EL device according to claim 15, characterized in that it is a method for manufacturing an organic EL device.

17. In the coating step, the third liquid is applied between four second dot regions arranged in a 2x2 grid from among the plurality of second dot regions. A method for manufacturing an organic EL device according to any one of claims 1 to 5.

18. The third liquid is applied to the substrate, avoiding the contact holes. A method for manufacturing an organic EL device according to any one of claims 1 to 5.

19. The third liquid is applied to the region including the contact hole. A method for manufacturing an organic EL device according to any one of claims 1 to 5.

20. In the coating step, the fourth liquid is applied to the outer periphery of the main surface of the substrate. A method for manufacturing an organic EL device according to any one of claims 1 to 5.

21. The fourth liquid is a liquid with the same components as the third liquid. A method for manufacturing an organic EL device according to claim 20, characterized in that it is a method for manufacturing an organic EL device.

22. Liquid dispensing section, A substrate holding portion that holds a substrate having a main surface including a plurality of first dot regions arranged in a matrix, and a plurality of second dot regions arranged in a matrix, each smaller in size than the first dot region, The system comprises a control unit for controlling the liquid discharge unit, The control unit controls the liquid dispensing unit to apply the first liquid to each of the plurality of first dot regions, the second liquid to each of the plurality of second dot regions, and the third liquid between the plurality of second dot regions. A coating apparatus characterized by the following features.

23. The first liquid and the second liquid are liquids containing functional materials. The third liquid mentioned above is a liquid that does not contain functional materials. The aforementioned liquid dispensing unit is A first head for dispensing the first liquid and the second liquid, A second head for discharging the third liquid, The coating apparatus according to feature 22.

24. The first liquid, the second liquid, and the third liquid are liquids containing a functional material. The liquid dispensing unit includes a head for dispensing the first liquid, the second liquid, and the third liquid. The coating apparatus according to feature 22.

Images