Method for manufacturing organic el device and coating apparatus

Abstract

The invention provides a method for manufacturing an organic EL device and a coating apparatus, wherein the method facilitates uniform film thickness distribution. A method for manufacturing an organic EL device includes: a step for 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 plurality of second dot regions being smaller than each of the plurality of first dot regions; and an application step for 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.

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing an organic EL device and a coating device for manufacturing the organic EL device. Background Art

[0002] When manufacturing an organic EL device having a panel (organic EL panel) having an OLED (Organic Light Emitting Diode) as an organic EL (Electro Luminescence) element, a method of applying a solution film to a desired portion on a substrate using an inkjet device is known. The 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, that is, 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 (sub-pixels) divided by banks is prepared, ink is applied to each groove region, the substrate and the ink are dried, and a functional film of a pixel is formed in each groove region.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2015 / 166647 Summary of the invention

[0007] Problem that the invention aims to solve

[0008] When two or more panels of different sizes are manufactured from one substrate, that is, when the substrate has a plurality of first point regions and a plurality of second point regions and each of the plurality of second point regions is smaller than each of the plurality of first point regions, in the process of drying the substrate, a deviation may occur between the drying speed of the film in the first point region and the drying speed of the film in the second point region. As a result, a deviation may occur in the film thickness distribution of the films formed in the first point region and the second point region, respectively.

[0009] Solutions for solving problems

[0010] The first technical solution disclosed in the present invention is a method for manufacturing an organic EL device, characterized in that the manufacturing method includes: a process of preparing a substrate, the substrate having a main surface including a plurality of first point areas arranged in a matrix and a plurality of second point areas arranged in a matrix, each of the plurality of second point areas being smaller than each of the plurality of first point areas; and a coating process, coating the first liquid on the plurality of first point areas respectively, coating the second liquid on the plurality of second point areas respectively, and coating the third liquid between the plurality of second point areas.

[0011] The second technical solution of the present disclosure is a coating device, characterized in that the coating device includes: a liquid ejecting unit; a substrate holding unit, which holds a substrate, the substrate having a main surface including a plurality of first point areas arranged in a matrix and a plurality of second point areas arranged in a matrix, each of the plurality of second point areas being smaller than each of the plurality of first point areas; and a control unit, which controls the liquid ejecting unit, the control unit controls the liquid ejecting unit to respectively apply the first liquid to the plurality of first point areas, respectively apply the second liquid to the plurality of second point areas, and apply the third liquid between the plurality of second point areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram showing the structure of a manufacturing system as an example of the system according to the first embodiment.

[0013] Figure 2a It is an explanatory diagram of the coating device according to the first embodiment. Figure 2b It is an explanatory diagram of the coating device and the substrate according to the first embodiment.

[0014] Figure 3a This is an explanatory diagram of a part of the first panel region in the first embodiment. Figure 3b This is an explanatory diagram of a part of the second panel region in the first embodiment. Figure 3c It is a cross-sectional view of the substrate according to the first embodiment.

[0015] Figure 4a It is an explanatory diagram of a part of the manufacturing process of the organic EL device of the first embodiment. Figure 4b It is an explanatory diagram of a part of the manufacturing process of the organic EL device of the first embodiment. Figure 4c It is an explanatory diagram of a part of the manufacturing process of the organic EL device of the first embodiment. Figure 4d It is an explanatory diagram of a part of the manufacturing process of the organic EL device of the first embodiment. Figure 4e It is an explanatory diagram of a part of the manufacturing process of the organic EL device of the first embodiment.

[0016] Figure 5aIt is an explanatory diagram of a part of the manufacturing process of the organic EL device of the first embodiment. Figure 5b This is an explanatory diagram of a part of the second panel region of Modification Example 1.

[0017] Figure 6a It is an explanatory diagram of a coating device and a substrate according to a second embodiment. Figure 6b This is an explanatory diagram of a part of the second panel region in the second embodiment.

[0018] Figure 7a It is an explanatory diagram of a part of the manufacturing process of the organic EL device of the second embodiment. Figure 7b It is an explanatory diagram of a part of the manufacturing process of the organic EL device of the second embodiment. Figure 7c It is an explanatory diagram of a part of the manufacturing process of the organic EL device of the second embodiment. Figure 7d It is an explanatory diagram of a part of the manufacturing process of the organic EL device of the second embodiment.

[0019] Figure 8a It is an explanatory diagram of a part of the manufacturing process of the organic EL device of a comparative example. Figure 8b It is an explanatory diagram of a part of the manufacturing process of the organic EL device of a comparative example. Figure 8c It is an explanatory diagram of a part of the manufacturing process of the organic EL device of a comparative example. Figure 8d It is an explanatory diagram of a part of the manufacturing process of the organic EL device of a comparative example.

[0020] Description of Reference Numerals

[0021] S1, ink (first liquid); S2, ink (second liquid); S3, liquid (third liquid); S4, liquid (fourth liquid); 1, substrate; 11, main surface; 21, dot area (first dot area); 22, dot area (second dot area); 31, dot area group (first group); 32, dot area group (second group); 41, panel area (first panel area); 42, panel area (second panel area); 50, recessed portion; 120, control unit (control unit); 140, liquid ejecting portion. DETAILED DESCRIPTION

[0022] Hereinafter, the exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The following embodiments illustrate the preferred structures of the present disclosure by way of example, and for example, those skilled in the art can appropriately change the detailed structures to implement the present disclosure without departing from the main purpose of the present disclosure. In addition, for the drawings referred to in the description of the following embodiments, unless there are special remarks, the elements indicated by the same reference figure numerals have the same functions. In addition, since these drawings are schematically represented for the convenience of illustration and description, they are not limited to strict consistency in shape, size, configuration, etc. between the drawings.

[0023] In the following embodiments, directions are represented by an XYZ coordinate system which is a rectangular coordinate system. The X direction, the Y direction, and the Z direction are orthogonal to each other. In the XYZ coordinate system, the XY plane is a horizontal plane, and the XZ plane and the YZ plane are vertical planes. The X direction and the Y direction are horizontal directions. The negative direction of the Z axis is the vertical direction (gravity direction), in other words, the downward direction. In addition, the positive direction of the Z axis is the upward direction.

[0024] In the following description, for example, when the positive direction of the X-axis is recorded, it refers to the same direction as the direction indicated by the arrow of the X-axis in the XYZ coordinate system, and when the negative direction of the X-axis is recorded, it refers to the direction 180 degrees opposite to the direction indicated by the arrow of the X-axis in the XYZ coordinate system. In addition, when it is simply recorded as the X direction, it refers to the direction parallel to the X-axis regardless of the difference in the direction indicated by the arrow of the X-axis. The same applies to the Y-axis and Z-axis other than the X-axis.

[0025] In the following description, ink refers to a liquid (solution) containing a functional material for forming a functional film of an organic EL element.

[0026] [First embodiment]

[0027] Figure 1 1 is a schematic diagram showing a configuration of a manufacturing system 1000 as an example of a system according to Embodiment 1. The manufacturing system 1000 is a system for manufacturing organic EL devices used in a display device.

[0028] The manufacturing system 1000 is configured to include, for example, a film forming device for forming an organic film on the 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 EL element (OLED). The process of manufacturing the organic EL element can include the following steps: applying a solution containing a functional material to form an organic film such as a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer on the substrate 1.

[0029] The process of forming an organic film on the substrate 1 may include, for example, a coating process of coating a film-forming solution on the substrate 1 by 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 of promoting evaporation under a reduced pressure environment lower than the atmospheric pressure. For example, the evaporation of the solvent may be promoted at a temperature higher than normal 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.

[0030] The manufacturing system 1000 includes a plurality of processing units for performing certain processing on a substrate and a conveying mechanism 900 for conveying the substrate between the plurality of processing units. Each processing unit may include a processing chamber. The manufacturing system 1000 includes a conveying chamber 110 connected to each processing chamber of the plurality of processing units. The conveying mechanism 900 may be arranged in the conveying chamber 110. The conveying chamber 110 may be arranged in a manner surrounded by the processing chambers of the plurality of processing units. The manufacturing system 1000 may be a manufacturing system for articles in a multi-chamber form.

[0031] In one example, the plurality of processing units include a coating unit 100 that applies a film-forming solution to the substrate 1 by an inkjet method, and a drying unit 400 that dries the film-forming solution applied to the substrate 1 by the coating unit 100. In addition, the plurality of processing units may include, for example, a load lock unit 200, an unload lock unit 300, a processing unit 500, a processing unit 600, a processing unit 700, and a processing unit 800.

[0032] The load lock unit 200 is used as an interface for transferring the substrate 1 from the outside of the manufacturing system 1000 to the inside of the manufacturing system 1000. The unload lock unit 300 is configured as an interface for transferring the substrate 1 after the processing of 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.

[0033] The drying unit 400 is configured to dry the film-forming solution applied on the substrate 1 by the coating unit 100 to form a dry film. The processing units 500 to 800 can be processing chambers for performing various processes in accordance with the device characteristics such as cooling and alignment. In addition, the number of processing units is not limited to the example shown in the figure, and can be increased or decreased.

[0034] The conveying mechanism 900 is, for example, a conveying robot. The conveying robot is configured to hold the substrate, and to convey the substrate from the coating unit 100 to any processing chamber and to convey the substrate from the processing chamber. For example, the conveying robot is configured to convey the substrate from the coating unit 100 along a straight path, for example, to convey the substrate straightly into any processing chamber after changing the direction of the substrate toward the processing chamber by a rotation action.

[0035] Alternatively, you can Figure 1 As illustrated, the transport chamber 111 is provided between the coating unit 100 and the transport chamber 110. In the first embodiment, the transport chamber 111 can be configured to transport the substrate 1 sent out from the coating unit 100 straightly to the transport mechanism 900 without changing the orientation of the substrate 1.

[0036] The manufacturing system 1000 may further include a control unit 120. The control unit 120 may be composed of hardware such as an FPGA (Field Programmable Gate Array). The control unit 120 may also be composed of a PLD (Programmable Logic Device) or an ASIC (Application Specific Integrated Circuit). Alternatively, the control unit 120 may be composed of a general-purpose or dedicated computer loaded with a program (software), or may be composed of a combination of all or part of the aforementioned devices.

[0037] The control unit 120 can include a CPU, an I / O port, and a computer-readable recording medium. As a computer-readable recording medium, a non-transient recording medium that stores a processing program executed by the CPU, parameters required for the execution of the processing, etc. can be used. As a non-transient recording medium, for example, a floppy disk, an optical disk, a magneto-optical disk, a magnetic tape, a USB memory, an SSD, etc. can be used. In addition, the information processing device can include a rewritable storage medium (RAM, etc.) that provides a recording area required for processing such as calculations.

[0038] 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 provided in the control unit 120 stores a program for the manufacturing system 1000 to manufacture a substrate for an organic EL device.

[0039] 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.

[0040] Figure 2a It is an explanatory diagram of the coating device 150 according to the first embodiment. Figure 2b 1 is an explanatory diagram of a coating device 150 and a substrate 1 according to the first embodiment. Figure 2b Omitted Figure 2a FIG. 1 is a diagram showing a part of the structure of the coating device 150. The coating unit 100 of the coating device 150 includes a mounting table 130 as an example of a substrate holding portion capable of holding the substrate 1 and a liquid discharge portion 140 for discharging liquid.

[0041] use Figure 1The transport mechanism 900 shown in the figure positions the substrate 1 with high precision and transports it to the stage 130. At this time, the substrate 1 is transported to the stage 130 with the main surface 11 of the substrate 1 facing upward. The liquid ejection unit 140 includes a head 141 as an example of a first head and a head 142 as an example of a second head. The head 141 is an inkjet head that ejects droplets of a supplied liquid from a nozzle. The head 142 is also an inkjet head that ejects droplets of a supplied liquid from a nozzle, and its basic structure is the same as that of the head 141.

[0042] The heads 141 and 142 are linear inkjet heads extending in the Y direction, respectively, and have a plurality of nozzles arranged in the Y direction. Each head 141 and 142 can apply liquid to a desired portion of the main surface 11 of the substrate 1 by scanning in the positive direction of the X axis as the scanning direction and ejecting droplets. In addition, each head 141 and 142 is not limited to a linear inkjet head, and can also be configured to scan in the Y direction.

[0043] The liquid ejection unit 140 includes a rail 145 and a driving device 147. The heads 141 and 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 and 142 and the driving device 147. In the first embodiment, the case where the heads 141 and 142 move relative to the substrate 1 is described as an example, but the present invention is not limited thereto, and the mounting table 130 holding the substrate 1 may also move relative to the heads 141 and 142.

[0044] The substrate 1 has a glass substrate, 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 substrate. The bank is formed in the shape of the organic EL element, that is, the shape of the dot area, on the main surface 11 of the substrate 1. The bank defines a concave portion capable of holding a solution in each dot area. A contact hole connecting the lower electrode and the TFT element is also formed in the substrate of the substrate 1.

[0045] In the first embodiment, one pixel is composed of dots (sub-pixels) of three colors, RGB. That is, one pixel is composed of three dots, i.e., three sub-pixels. R is red, G is green, and B is blue. In addition, the number of sub-pixels included in one pixel is not limited to three.

[0046] like Figure 2b As shown, the main surface 11 of the substrate 1 has a dot region group 31 including a plurality of dot regions 21 defined by banks and a dot region group 32 including a plurality of dot regions 22 defined by banks. The dot region group 31 is an example of the first group, and the dot region group 32 is an example of the second group.

[0047] In a plan view, that is, when viewed in the Z direction, the dot region 22 is smaller in 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.

[0048] The dot region 21 is a region where a light emitting portion emitting light of any one of RGB colors is formed. The dot region 22 is also a region where a light emitting portion emitting light of any one of RGB colors is formed. In other words, the dot regions 21 and 22 are sub-pixel regions.

[0049] The plurality of dot regions 21 are arranged in a matrix at intervals from each other. Figure 2b In the embodiment, a plurality of dot regions 21 are arranged at intervals from each other in the X direction and the Y direction. A plurality of dot regions 22 are arranged at intervals from each other in a matrix. Figure 2b In the embodiment, a plurality of dot regions 22 are arranged at intervals from each other in the X direction and the Y direction.

[0050] The dot region group 31 is included in the panel region 41 shown by the dotted line. The panel region 41 is a region that becomes an organic EL panel. The dot region group 32 is included in the panel region 42 shown by the dotted line. The panel region 42 is a region that becomes 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 the first region group, and the dot region group 32 is an example of the second region group. The panel region 41 is an example of the first panel region, and the panel region 42 is an example of the second panel region. The substrate 1 is then cut into individual panels.

[0051] 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 including the dot region group 31. The panel region 42 is a region including the dot region group 32.

[0052] The organic EL panel formed by the panel area 41 can be used for a display of a large television, for example, and the organic EL panel formed by the panel area 42 can be used for a display of a notebook computer, for example. The smaller the area of ​​the panel area, the higher the resolution (dpi), that is, the more pixels per unit area. Therefore, the resolution of the organic EL panel formed by the panel area 42 is higher than that of the organic EL panel formed by the panel area 41.

[0053] 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 the solvent contained in the applied ink.

[0054] The ink as a liquid is composed of, for example, a solution containing a solute (functional material) and a solvent for forming an organic film. The solvent contained in the ink preferably has a property of promoting evaporation under a reduced pressure environment lower than the atmospheric pressure. It is preferred that, for example, the evaporation of the solvent is promoted at a temperature higher than normal temperature (25° C.). The solute is a functional material for forming an OLED.

[0055] The solvent is preferably an organic solvent. The solvent contains at least one 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 glycidyl ether, 1,3-octanediol, diethylene glycol, dipropylene glycol, triethylene glycol, Tripropylene glycol, 1,3-butanediol, 1,4-butanediol, 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, ethyl cellosolve acetate, etc.

[0056] The organic film is an organic layer, for example, any one of the hole injection layer, hole transport layer, light emitting layer, electron transport layer or electron injection layer of an OLED. The manufacture of an organic EL element includes a process of forming each organic film of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer and an electron injection layer at a predetermined position on a substrate 1.

[0057] Figure 8a to Figure 8d This is a diagram for explaining a part of the manufacturing process of an organic EL device of a comparative example. Figure 8a to Figure 8d Schematically illustrates a cross section of a substrate 1X of a comparative example.

[0058] like Figure 8a As shown, a substrate 1X having a panel region 41X including a plurality of dot regions 21X and a panel region 42X including a plurality of dot regions 22X is prepared. When viewed from above, that is, when viewed along the Z direction, the panel region 42X is smaller in size than the panel region 41X, and the dot region 22X is smaller in size than the dot region 21X. In addition, the pitch of the dot region 22X in the X direction is smaller than the pitch of the dot region 21X in the X direction, and the pitch of the dot region 22X in the Y direction is smaller than the pitch of the dot region 21X in the Y direction. The dot region 21X is delimited by the bank 81X, and the dot region 22X is delimited by the bank 82X.

[0059] like Figure 8bAs shown, the head 4X applies a first amount of ink S1X to the dot region 21X, and applies a second amount of ink S2X, which is smaller than the first amount, to the dot region 22X. The ink S2X is a solution of the same type as the ink S1X.

[0060] Next, the substrate 1X coated with the inks S1X and S2X is transported to a drying unit to dry the substrate 1X. Here, the surface area of ​​the ink S1X in the panel area 41X is larger than the surface area of ​​the ink S2X in the panel area 42X. Figure 8c As shown, the solvent vapor pressure above the panel region 41X is higher than the solvent vapor pressure above the panel region 42X. Therefore, the panel region 42X having a lower solvent vapor pressure than the panel region 41X dries faster than the panel region 41X.

[0061] When there is a difference in the time when drying ends, the solvent moves from the area with a slower drying speed to the area with a faster drying speed in each of the dot regions 21X and 22X. Figure 8d As shown in FIG. 1 , dry films F1X and F2X are formed whose upper surfaces are inclined with respect to the horizontal plane, and the dry films F1X and F2X have uneven film thickness.

[0062] Therefore, in the first embodiment, in the drying process, the amount of ink applied to the panel area 42 in the coating process is adjusted so that the pressure above the panel area 41 and the pressure above the panel area 42 become uniform, that is, the pressure distribution in the space above the substrate 1 becomes uniform.

[0063] Figure 3a It is an explanatory diagram of a part of the panel area 41 according to the first embodiment. Figure 3b It is an explanatory diagram of a part of the panel area 42 according to the first embodiment. Figure 3c 1 is a cross-sectional view of the substrate 1 according to the first embodiment. Figure 3c The substrate 1 is schematically shown along Figure 2b The cross section along line AA is shown.

[0064] The size of the dot region 22, that is, the area A2 of the dot region 22 observed in the Z direction, is smaller than the size of the dot region 21, that is, the area A1 of the dot region 21 observed in the Z direction. In addition, the pitch P2X of the dot region 22 in the X direction is smaller than the pitch P1X of the dot region 21 in the X direction, and the pitch P2Y of the dot region 22 in the Y direction is smaller than the pitch P1Y of the dot region 21 in the Y direction. The dot region 21 is a concave portion defined by the bank 81, and the dot region 22 is a concave portion defined by the bank 82.

[0065] In the first embodiment, the main surface 11 of the substrate 1 has a recess 50 formed between a plurality of dot regions 22 and capable of retaining a liquid. The recess 50 is formed outside the dot region 22 so as not to overlap with the dot region 22. Figure 3b As shown, the recess 50 is formed avoiding the contact hole 70 formed between the plurality of dot regions 22 .

[0066] 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 while 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 while avoiding the plurality of dot regions 22.

[0067] The recess 50 is arranged between the four dot areas 22 arranged in two rows and two columns. That is, it is arranged at the center of the smallest rectangular area sandwiched by the four dot areas 22 and surrounding the four dot areas 22. When viewed from above, that is, when viewed along the Z direction, the recess 50 is, for example, circular in shape. Figure 3b In the example of FIG. 5 , the recess 50 is arranged between two contact holes 70 in the Y direction. Figure 3c As shown, the recess 50 is defined by a bank 83 .

[0068] Furthermore, in the first embodiment, if Figure 2b As shown, the main surface 11 of the substrate 1 has a recess 60 as at least one recess formed outside the plurality of panel regions 41 and the plurality of panel regions 42 and in the outer periphery of the main surface 11. Figure 2b In the example, the recess 60 is a series of grooves formed along the outer periphery of the main surface 11, but the present invention is not limited thereto. For example, as at least one recess, a plurality of recesses may be arranged at intervals along the outer periphery of the main surface 11. Figure 3c As shown, the recess 60 is defined by the bank 84. Figure 2b There is no concave portion 50 on the line A-A shown, but Figure 3c In FIG. 1 , for convenience of explanation, the recessed portion 50 is shown.

[0069] In addition, in order to adjust the amount of solvent in the panel area 41, it is also possible to Figure 3a As shown in FIG. 1 , a concave portion 61 capable of holding a liquid is formed between the plurality of dot regions 21. Figure 3c As shown, the recess 61 is defined by a bank 85 .

[0070] Figure 4a to Figure 4e and Figure 5a FIG. 1 is a diagram for explaining a part of the manufacturing process of the organic EL device according to the first embodiment. Figure 4a to Figure 4e Schematically illustrates a cross section of the substrate 1 .

[0071] First, prepare Figure 4a The substrate 1 shown in FIG. Figure 1 The substrate 1 is transported inside the coating chamber of the coating unit 100 shown in FIG. Figure 4b As shown, the control unit 120 causes the head 142 to scan, and the liquid S3 and the liquid S4 are ejected from the head 142, and the liquid S3 is applied to the concave portion 50, and the liquid S4 is applied to the concave portion 60. That is, the liquid S3 is applied between the plurality of 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 the four dot regions 22 arranged in two rows and two columns. At this time, by applying the liquid S3 to the concave portion 50, the liquid S3 is retained in the concave portion 50, and the situation of diffusion outside the concave portion 50 is reduced. By applying the liquid S4 to the concave portion 60, the liquid S4 is retained in the concave portion 60, and the situation of diffusion outside the concave portion 60 is reduced.

[0072] As described above, the liquid S3 and the liquid S4 are applied to the recessed portions 50 and 60 of the substrate 1 using the head 142. The liquid S3 is an example of the third liquid, and the liquid S4 is an example of the fourth liquid.

[0073] The liquid S4 is a liquid having the same component and composition as the liquid S3. The recessed portions 50 and 60 are dummy regions different from the dot regions 21 and 22 where dots of pixels are formed.

[0074] In addition, in the case where the composition of liquid S4 is different from that of liquid S3, two heads may be prepared to replace one head 142, and liquid S3 may be applied to each recess 50 of the substrate 1 using one of the two heads, while liquid S4 may be applied to the recess 60 of the substrate 1 using the other head.

[0075] Then, if Figure 4c As shown, the control unit 120 causes the head 141 to scan, and the ink S1 and the ink S2 are ejected from the head 141, so that the ink S1 is applied to the dot area 21, and the ink S2 is applied to the dot area 22. The ink S1 is an example of the first liquid, and the ink S2 is an example of the second liquid. The first amount of the ink S1 is applied to the dot area 21, and the second amount of the ink S2, which is less than the first amount, is applied to the dot area 22.

[0076] Inks S1 and S2 are solutions (liquids) for forming functional films of organic EL elements, respectively, and are solutions (liquids) containing functional materials. In the first embodiment, ink S2 is a liquid having the same components and composition as ink S1. In addition, ink S2 may have a slightly different composition (amount of components) from ink S1.

[0077] In addition, when making the composition of ink S2 different from that of ink S1, two heads can be prepared to replace one head 141, and one of the two heads can be used to apply ink S1 to each dot area 21 of the substrate 1, and the other head can be used to apply ink S2 to each dot area 22 of the substrate 1.

[0078] On the other hand, since the recesses 50 and 60 to which the liquids S3 and S4 are applied are dummy regions that do not become pixels, it is preferred that the liquids S3 and S4 evaporate and disappear from the substrate 1 during the drying process. Therefore, the liquids S3 and S4 are preferably liquids that do not contain functional materials. For example, the liquids S3 and S4 preferably contain at least one of the organic solvents described above. Thus, after the substrate 1 is dried, no residues remain in the recesses 50 and 60.

[0079] As described above, the area of ​​the panel region 42 is smaller than the area of ​​the panel region 41, and the amount of ink S2 per unit area of ​​the panel region 42 is less than the amount of ink S1 per unit area of ​​the panel region 41. In the first embodiment, by applying the liquid S3 in the panel region 42, the difference between the amount of liquid per unit area of ​​the panel region 41 and the amount of liquid per unit area of ​​the panel region 42 can be reduced, and the liquid can be evenly applied to the main surface 11 of the substrate 1.

[0080] From the viewpoint of making the pressure distribution on the substrate 1 due to the evaporation of the solvent uniform in the subsequent drying process, the liquids S3 and S4 are preferably liquids having the same components and the same composition as the solvents contained in the inks S1 and S2. In addition, after the substrate 1 is dried, no residue can be left in the recesses 50 and 60.

[0081] In the first embodiment, the recessed portion 50 and the recessed portion 60 are formed avoiding the contact hole 70. That is, the liquids S3 and S4 are applied to the substrate 1 avoiding the contact hole 70. Therefore, the liquids S3 and S4 are not limited to solvents that do not contain functional materials, and although a useless functional film is formed in the recessed portion 50 or the recessed portion 60, the liquid S3 or the liquid S4 may be a liquid having the same components as the ink S1 or the ink S2.

[0082] Alternatively, whether or not to apply the liquid S4 to the recessed portion 60 may be determined according to the difference between the amount of ink applied to the panel region 41 and the amount of ink applied to the panel region 42 .

[0083] Above, in Figure 4a to Figure 4c In the coating process shown, the control unit 120 controls the heads 141, 142 and the driving device 147 of the liquid ejection unit 140, and applies ink S1 to the multiple dot areas 21 included in each dot area group 31, applies ink S2 to the multiple dot areas 22 included in each dot area group 32, applies liquid S3 to the multiple recesses 50 included in each panel area 42, and applies liquid S4 to the recesses 60.

[0084] In the first embodiment, in the coating process, the control unit 120 controls the liquid ejection unit 140 to apply the liquids S3 and S4 to the recesses 50 and 60 of the substrate 1 before applying the inks S1 and S2 to the dot regions 21 and 22 of the substrate 1. Thus, the solvent evaporates from the liquids S3 and S4, thereby forming a solvent atmosphere above the substrate 1, and reducing the evaporation of the solvent contained in the inks S1 and S2 to be applied later in the middle of the coating process and between the coating process and the drying process. The practice of first applying the liquid S4 to the recesses 60 located on the outer periphery of the main surface 11 of the substrate 1 is particularly suitable for forming a solvent atmosphere above the main surface 11 of the substrate 1. Thus, the amount of solvent evaporation of the inks S1 and S2 applied to the dot regions 21 and 22 can be reduced in the middle of the coating process and between the coating process and the drying process. Therefore, in the subsequent drying step, the pressure distribution on the substrate 1 can be made more stably uniform, the difference in drying speed can be reduced, and the thickness of the film can be made uniform, that is, the variation in the thickness of the film can be reduced.

[0085] Next, the control unit 120 controls the conveying mechanism 900 to convey the substrate 1 coated with the liquid from the coating unit 100 to the drying unit 400. Then, the control unit 120 controls the drying unit 400, as shown in FIG. Figure 4d As shown in FIG. 1 , the substrate 1 is dried, that is, the liquid (solvent) applied to the substrate 1 is evaporated. Figure 4e As shown, dry films F1 and F2 are formed in the dot regions 21 and 22 by using the functional materials contained in the inks S1 and S2. Figure 4d and Figure 4e In the drying step shown, the substrate 1 coated with the inks S1 and S2 and the liquids S3 and S4 is dried.

[0086] In the first embodiment, as Figure 4d As shown, since the liquid S3 is applied to the panel area 42, the difference between the amount of solvent in the panel area 41 and the amount of solvent in the panel area 42 is reduced, so that the solvent vapor pressure above the substrate 1, that is, the pressure distribution, can be made uniform. As a result, the difference in drying speed can be reduced, and the thickness of the film can be made uniform, that is, the deviation of the thickness of the film can be reduced.

[0087] In addition, the solvent contained in the ink of the dot region near the periphery of the main surface 11 of the substrate 1 is easier to evaporate than the solvent contained in the ink of the dot region in the central portion of the main surface 11. Therefore, in order to reduce the situation where the ink of the dot region near the periphery of the main surface 11 of the substrate 1 dries earlier than the ink of the dot region in the central portion, it is preferred to apply the liquid S4 to the recessed portion 60.

[0088] After the drying step, the substrate is baked in various atmospheres, temperatures, and times according to the film properties, thereby forming a functional film of the organic EL element in the dot regions 21 and 22 .

[0089] When manufacturing an organic EL element, the above-mentioned coating step, drying step and baking step are repeated as many times as necessary to form a plurality of layers of the organic EL element, for example, a hole injection layer, a hole transport layer and a light emitting layer.

[0090] 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 vapor deposition process to form a sealing film or a sealing structure. Then, in a cutting process, the Figure 2b The dotted lines representing the panel regions 41 and 42 cut through the substrate 1, so that Figure 5a As shown, multiple panels P1 and multiple panels P2 are obtained.

[0091] In this way, a plurality of panels P1 and a plurality of panels P2 are manufactured from one substrate 1. Panels P1 and P2 are organic EL panels of different sizes (areas). That is, panel P2 is an organic EL panel of smaller size (area) than panel P1. Organic EL devices such as displays are manufactured using organic EL panels.

[0092] Here, calculation of the ink amount for each panel is described. The ink amount per unit area of ​​each panel can be described as follows. In the following description of the ink amount, ink also includes liquid that does not contain a functional material.

[0093] Ink volume per unit area = (ink volume in dot area + ink volume in concave area) / panel area

[0094] As for the dot area, the amount of ink required for each color R, G, and B is usually different, but since the intervals between the dot areas are very close, at tens to hundreds of μm, the solvent atmosphere between the R, G, and B dot areas does not differ much.

[0095] Therefore, the amount of ink required for one pixel only needs to consider the sum of the ink amounts of each RGB color. The total amount of ink per panel is obtained by adding the sum of the ink amounts, for example, to the amount of ink in the concave portion, and then divided by the panel area, so that the amount of ink per unit area of ​​each panel can be calculated.

[0096] For example, in a large panel such as a large television, no ink is required for areas other than the dot area 21 , whereas in a small panel such as a notebook computer, the amount of ink applied to the recessed portion 50 between the plurality of dot areas 22 is adjusted.

[0097] According to this method, when a small panel and a large panel with a small amount of ink per unit area are manufactured by combining one substrate 1, the difference in drying speed between the panels can be reduced by applying ink or solvent to the concave portion 50 of the small panel with a small amount of ink. As a result, the film thickness of the formed film, such as the deviation of the film shape of the light-emitting layer, can be reduced. That is, the brightness unevenness caused by the deviation of the film shape of the light-emitting layer can be reduced, and an organic EL device that can obtain the desired light-emitting characteristics can be manufactured. In addition, since the thickness of the film can be made uniform, the situation of local concentration of current can be reduced, and the life of the pixel (dot) can be extended.

[0098] 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.

[0099] [Variation 1 of the first embodiment]

[0100] Figure 5b FIG. 4 is a partial explanatory diagram 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, and preferably a liquid having the same composition as the solvent contained in the ink S2. Since the liquid S3 evaporates from the substrate 1 during the drying process, no residue of the liquid S3 remains on the substrate 1. Therefore, the liquid S3 may be Figure 5b As shown in FIG. 1 , a recess 51 is formed in a region including the contact hole 70 instead of the recess 50. In this way, the recess 51 can be set larger than the recess 50 without avoiding the contact hole 70. Figure 5b In the example of , the concave portion 51 is an oblong region that is longer in the Y direction than the two or more dot regions 22. That is, even if the liquid S3 is applied to the contact hole 70, no residue of the liquid S3 remains, so that the electrical characteristics of the contact hole 70 are not affected, and the degree of freedom in adjusting the amount of solvent in the panel region 42 is improved.

[0101] In the first embodiment, the case where panels P1 and P2 of two sizes are manufactured from one substrate 1 is described, but the present invention is not limited thereto, and panels of three or more sizes may be manufactured from one substrate.

[0102] In the first embodiment, the case where the liquid S3 is a liquid different from the ink S2 is described, but the present invention is not limited thereto, and the liquid S3 may be a liquid having the same component as the ink S2. In this case, either of the heads 141 and 142 may be omitted, and one head may be used to scan twice.

[0103] [Second embodiment]

[0104] Hereinafter, unless otherwise specified, elements denoted by the same reference numerals as those of the first embodiment have substantially the same structure and function as those described in the first embodiment, and the differences from the first embodiment will be mainly described.

[0105] Figure 6a 1 is an explanatory diagram of a coating device 150A and a substrate 1 according to a second embodiment. The coating device 150A includes a mounting table 130, a liquid ejecting unit 140A, and Figure 1 The control unit 120 shown. In the coating device 150A of the second embodiment, a liquid ejection unit 140A is provided in place of the liquid ejection unit 140 of the coating device 150 of the first embodiment.

[0106] Ink S1, ink S2, liquid S3, and liquid S4 are liquids having the same components and the same composition. The liquid ejection unit 140 of the first embodiment includes two heads 141 and 142, but the liquid ejection unit 140A of the second embodiment includes one head 14. That is, the liquid ejection unit 140A has a substantially same structure as the structure in which one of the two heads 141 and 142 is omitted from the liquid ejection unit 140. The liquid ejection unit 140A includes a track (not shown) and a driving device (not shown).

[0107] Figure 6b It is an explanatory diagram of a part of the panel region 42 of the second embodiment. The recessed portion 50 is formed so as to avoid the contact hole 70 formed between the plurality of dot regions 22 .

[0108] Figure 7a to Figure 7d FIG. 1 is a diagram for explaining a part of the manufacturing process of the organic EL device according to the second embodiment. Figure 7a to Figure 7d The substrate 1 is schematically shown along Figure 6a The cross section of line BB is shown.

[0109] First, if Figure 7a As shown in FIG. 1 , a substrate 1 is prepared and placed in a coating chamber of a coating device 150A. Figure 7b As shown, the control unit 120 causes the head 14 to scan, and ink S1, ink S2, liquid S3, and liquid S4 are ejected from the head 14, ink S1 is applied to the dot area 21, ink S2 is applied to the dot area 22, liquid S3 is applied to the concave portion 50, and liquid S4 is applied to the concave portion 60. In the second embodiment, since ink S1, ink S2, liquid S3, and liquid S4 are the same components, it is sufficient to scan the head 14 only once in the positive direction of the X axis. Figure 7c and Figure 7d The drying process shown is similar to that of the first embodiment. Figure 4d and Figure 4e The drying steps shown are the same, so the description is omitted.

[0110] 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.

[0111] As described above, according to the present disclosure, a technique that is advantageous for making the film thickness distribution uniform can be provided.

[0112] The present disclosure is not limited to the above-described embodiments, and the embodiments can be modified in many ways within the technical concept of the present disclosure. In addition, the effects described in the present embodiment are merely the best effects produced by the embodiments of the present disclosure, and the effects of the embodiments of the present disclosure are not limited to the contents described in the present embodiment.

Claims

1. A method for manufacturing an organic EL device, characterized in that: The manufacturing method comprises: 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 the plurality of second dot regions being smaller than each of the plurality of first dot regions; and The coating step includes coating the first liquid on each of the plurality of first dot regions, coating the second liquid on each of the plurality of second dot regions, and coating the third liquid between the plurality of second dot regions.

2. The method for manufacturing an organic EL device according to claim 1, characterized in that: The manufacturing method further includes a drying step of drying the substrate coated with the first liquid, the second liquid, and the third liquid.

3. The method for manufacturing an organic EL device according to claim 2, characterized in that: The manufacturing method also includes a cutting step: cutting the substrate to obtain a first panel and a second panel, wherein the first panel includes a first group including the plurality of first point regions, and the second panel includes a second group including the plurality of second point regions.

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

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

6. The method for producing an organic EL device according to any one of claims 1 to 5, characterized in that: A pitch of the plurality of second dot regions is smaller than a pitch of the plurality of first dot regions.

7. The method for producing an organic EL device according to any one of claims 1 to 5, characterized in that: The second liquid is a liquid having the same component as the first liquid.

8. The method for producing an organic EL device according to any one of claims 1 to 5, characterized in that: The first liquid is a solution containing a functional material.

9. The method for producing an organic EL device according to any one of claims 1 to 5, characterized in that: The third liquid is a liquid having the same component as the second liquid.

10. The method for producing an organic EL device according to any one of claims 1 to 5, characterized in that: The third liquid is a liquid that does not contain a functional material.

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

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

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

14. The method for producing an organic EL device according to any one of claims 1 to 5, characterized in that: In the coating step, the third liquid is coated before the first liquid and the second liquid are coated.

15. The method for producing an organic EL device according to any one of claims 1 to 5, characterized in that: The substrate has a recessed portion, which is disposed between the plurality of second dot regions and holds the applied third liquid.

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

17. The method for producing an organic EL device according to any one of claims 1 to 5, characterized in that: In the coating step, the third liquid is coated between four second dot areas arranged in two rows and two columns among the plurality of second dot areas.

18. The method for producing an organic EL device according to any one of claims 1 to 5, characterized in that: The third liquid is applied to the substrate while avoiding the contact holes.

19. The method for producing an organic EL device according to any one of claims 1 to 5, characterized in that: The third liquid is applied to a region including the contact hole.

20. The method for producing an organic EL device according to any one of claims 1 to 5, characterized in that: In the coating step, the fourth liquid is coated on the outer peripheral portion of the main surface of the substrate.

21. The method for manufacturing an organic EL device according to claim 20, characterized in that: The fourth liquid is a liquid having the same component as the third liquid.

22. A coating device, characterized in that: The coating device comprises: Liquid ejection portion; 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 of the plurality of second dot regions being smaller than each of the plurality of first dot regions; and a control unit that controls the liquid ejection unit, The control unit controls the liquid ejection unit to apply the first liquid to each of the plurality of first dot regions, to apply the second liquid to each of the plurality of second dot regions, and to apply the third liquid between the plurality of second dot regions.

23. The coating device according to claim 22, characterized in that The first liquid and the second liquid are liquids containing functional materials, The third liquid is a liquid that does not contain a functional material, The liquid ejection unit comprises: a first head that ejects the first liquid and the second liquid; and The second head ejects the third liquid.

24. The coating device according to claim 22, characterized in that The first liquid, the second liquid, and the third liquid are liquids containing functional materials. The liquid ejection unit includes a head that ejects the first liquid, the second liquid, and the third liquid.

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