Drying apparatus and drying method

Abstract

A drying apparatus and a drying method are provided. The drying apparatus can include a stage to support a substrate and including a plurality of heating blocks to heat the substrate, and a drying upper plate disposed at an upper portion of the stage and including a plurality of solvent sensors to detect a concentration of a solvent vapor generated from the substrate at a plurality of locations.

Description

TECHNICAL FIELD

[0001] The present application relates to a drying apparatus and a drying method. BACKGROUND

[0002] Currently, as display apparatuses using various methods, representative examples include a liquid crystal display (LCD) and an organic light-emitting diode (OLED). The liquid crystal display is a display apparatus including a backlight unit and displaying an image by blocking or transmitting light emitted from the backlight unit. In addition, the organic light-emitting diode is a display apparatus that has recently attracted attention, and has a self-emission characteristic, unlike the liquid crystal display, and does not need an additional light source.

[0003] In manufacturing a substrate for such a display apparatus, various processes such as a process of depositing various materials on a substrate for an organic light-emitting diode and a heat treatment process such as a drying process and a baking process can be performed. The heat treatment process is performed in order to form a film having a desired characteristic and in order to induce a physical change or a chemical change of a material or to remove a carrier liquid. SUMMARY

[0004] The present application relates to a drying apparatus and a drying method.

[0005] The present application relates to a drying apparatus and a drying method.

[0006] The technical problems of the present application are not limited to the above-mentioned technical problems, and other technical problems not mentioned above will be clearly understood by those skilled in the art from the following description.

[0007] A drying apparatus according to an embodiment of the present application for achieving the above-mentioned technical problems can include a stage for supporting a substrate and including a plurality of heating blocks for heating the substrate, and a drying upper plate disposed at an upper portion of the stage and including a plurality of solvent sensors for detecting a concentration of solvent vapor generated from the substrate at a plurality of positions.

[0008] The plurality of positions can include a first position and a second position, the plurality of solvent sensors can include a first solvent sensor for detecting a first concentration of the solvent vapor at the first position and a second solvent sensor for detecting a second concentration of the solvent vapor at the second position, and the plurality of heating blocks can include a first heating block corresponding to the first position and a second heating block corresponding to the second position, wherein a heating temperature of the first heating block is set to be higher than a heating temperature of the second heating block if the first concentration is higher than the second concentration.

[0009] The heating temperature of the first heating block can be set to be lower than the heating temperature of the second heating block if the first concentration is lower than the second concentration.

[0010] The plurality of solvent sensors can be disposed in a diagonal line on the drying upper plate.

[0011] The plurality of solvent sensors can be disposed in an X shape on the drying upper plate.

[0012] The plurality of solvent sensors can be disposed in a cross shape on the drying upper plate.

[0013] The plurality of heating blocks can be disposed in an array shape on the object table.

[0014] The plurality of heating blocks can be disposed in a concentric quadrilateral shape on the object table.

[0015] The plurality of heating blocks can be disposed in a concentric circular shape on the object table.

[0016] The drying apparatus can further include a vacuum line connected to a vacuum pump to exhaust the solvent vapor.

[0017] A drying apparatus of an embodiment of the present invention for achieving the above technical task can include a plurality of heating blocks for heating a substrate, a plurality of solvent sensors for detecting a concentration of solvent vapor generated from the substrate at a plurality of positions, and a drying speed control apparatus for controlling a heating temperature of the plurality of heating blocks according to the concentration measured by the plurality of solvent sensors, thereby adjusting a drying speed of the substrate.

[0018] The plurality of positions can include a first position and a second position, the plurality of solvent sensors can include a first solvent sensor for detecting a first concentration of the solvent vapor at the first position and a second solvent sensor for detecting a second concentration of the solvent vapor at the second position, and the plurality of heating blocks can include a first heating block corresponding to the first position and a second heating block corresponding to the second position. In a case where the first concentration is higher than the second concentration, the drying speed control device can be configured to set a heating temperature of the first heating block to be higher than a heating temperature of the second heating block.

[0019] In a case where the first concentration is lower than the second concentration, the drying speed control device can be configured to set a heating temperature of the first heating block to be lower than a heating temperature of the second heating block.

[0020] The drying speed control device can include a first interface for receiving concentration data detected by the plurality of solvent sensors and a second interface for transmitting an instruction for setting a heating temperature of the plurality of heating blocks.

[0021] The drying speed control device can include a processor that receives an input of concentration data detected by the plurality of solvent sensors and calculates a heating temperature of the plurality of heating blocks.

[0022] The drying device can further include a vacuum line connected to a vacuum pump to exhaust the solvent vapor.

[0023] A drying method of an embodiment of the disclosure for achieving the above technical task can include the steps of: providing a substrate to a stage including a plurality of heating blocks; providing a drying upper plate including a plurality of solvent sensors to an upper portion of the stage; detecting concentrations of solvent vapor generated from the substrate at a plurality of positions using the plurality of solvent sensors; and controlling heating temperatures of the plurality of heating blocks according to the concentrations measured by the plurality of solvent sensors, thereby adjusting a drying speed of the substrate.

[0024] The plurality of positions can include a first position and a second position, the plurality of solvent sensors can include a first solvent sensor for detecting a first concentration of the solvent vapor at the first position and a second solvent sensor for detecting a second concentration of the solvent vapor at the second position, and the plurality of heating blocks can include a first heating block corresponding to the first position and a second heating block corresponding to the second position. In a case where the first concentration is higher than the second concentration, the drying speed control device can be configured to set a heating temperature of the first heating block to be higher than a heating temperature of the second heating block.

[0025] In the case where the first concentration is lower than the second concentration, the step of adjusting the drying speed can include a step of setting the heating temperature of the first heating block to be lower than the heating temperature of the second heating block.

[0026] The step of adjusting the drying speed can include a step of detecting the concentration and controlling the heating temperature according to a pre-set time pattern.

[0027] According to embodiments of the present application, by providing a plurality of solvent sensors on a drying upper plate and detecting the concentration distribution of solvent vapor inside a drying chamber in real time, the difference in the drying speed of the substrate by location can be detected, and by locally controlling the drying speed of locations where the difference is large, the thickness of the light emitting layer can be uniformly formed.

[0028] Further, according to embodiments of the present application, a drying speed control device is provided, which controls the heating temperature of a plurality of heating blocks according to the concentration measured by a plurality of solvent sensors, thereby adjusting the drying speed of a substrate, and thus can automatically perform drying speed adjustment and thickness adjustment of the light emitting layer. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a diagram of a drying apparatus for explaining an embodiment of the present application.

[0030] Figures 2 to 5 is a flowchart of a drying method for explaining an embodiment of the present application.

[0031] Figures 6 to 8 is a diagram of a drying upper plate for explaining an embodiment of the present application.

[0032] Figures 9 to 11 is a diagram of a stage for explaining an embodiment of the present application.

[0033] Figure 12 is a diagram of a drying apparatus for explaining an embodiment of the present application.

[0034] Figure 13 is a flowchart of a drying method for explaining an embodiment of the present application. DETAILED DESCRIPTION

[0035] Hereinafter, various embodiments of the present application will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present application pertains can easily practice the present application. The present application can be implemented in various forms and is not limited to the embodiments described herein.

[0036] For the sake of clearness of the present application, parts irrelevant to the explanation are omitted, and the same reference numerals are used for the same or similar structural elements throughout the specification.

[0037] Further, the size and the thickness of each structure shown in the drawings are arbitrarily shown for convenience, and thus the present application is not necessarily limited to the illustrated content. In the drawings, the thickness is exaggerated for the purpose of clear description of a plurality of layers and regions. Also, for the convenience of explanation, the thickness of some layers and regions is exaggerated in the drawings.

[0038] Further, when a part is said to be "on" or "above" another part, this includes not only the case where it is "directly on" or "directly above" the other part, but also the case where there is still another part therebetween. In contrast, when a part is said to be "directly on" or "directly above" another part, it means that there is no other part therebetween. Further, "on" or "above" a part serving as a reference means on or below the part serving as a reference, and does not necessarily mean "on" or "above" in the direction opposite to the direction of gravity.

[0039] Further, throughout the specification, when a part is said to "include" a certain structural element, this indicates that other structural elements can be further included unless specifically stated to the contrary.

[0040] Further, throughout the specification, when "planar" is mentioned, this indicates a case where the object part is viewed from above, and when "cross-sectional" is mentioned, this indicates a case where a cross-section of the object part after being vertically cut and viewed from the side.

[0041] Figure 1 FIG. 1 is a diagram for explaining a drying apparatus according to an embodiment of the present application.

[0042] Referring to Figure 1 , a drying apparatus 1 according to an embodiment of the present application can adjust a drying speed of ink in consideration of a distribution of a vapor concentration of the ink for a light-emitting layer in a case where an inkjet printing method is used, and can include a drying chamber 10 and a vacuum line 12. The inkjet printing method forms a light-emitting layer for each pixel by dropping the ink for the light-emitting layer for forming a light-emitting layer to a substrate in an inkjet printing chamber, and dries the substrate in the drying chamber 10, and detailed contents thereof will be described later with reference to Figures 2 to 5 .

[0043] A substrate 110 on which the ink for the light-emitting layer is dropped in the inkjet printing chamber can be transported into the drying chamber 10 so as to perform a drying process on the substrate 110. In the present embodiment, the drying chamber 10 can include a stage 100, a plurality of heating blocks 102, a drying upper plate 120, and a plurality of solvent sensors 122.

[0044] The stage 100 can support the substrate 110 in the drying process. The stage 100 can be a substrate tray or a chuck, but the scope of the present application is not limited thereto, and the stage 100 can be implemented to be movable up and down to adjust the distance between the stage 100 and the drying upper plate 120, as necessary.

[0045] The stage 100 can include a plurality of heating blocks 102. The plurality of heating blocks 102 can be disposed to contact or be close to the upper surface of the stage 100, thereby heating the substrate 110 mounted on the stage 100. The plurality of heating blocks 102 are heated at a temperature suitable for adjusting the drying speed of the ink on the substrate 110, and can be generally set to have a heating temperature lower than that of a subsequent baking process.

[0046] In particular, the plurality of heating blocks 102 can be set such that the heating blocks corresponding to different positions can have different heating temperatures, respectively. In other words, for the plurality of heating blocks 102, the heating block 102 corresponding to each position can be controlled with respect to a plurality of positions between the substrate 110 and the drying upper plate 120. For example, the plurality of positions can include a first position and a second position between the substrate 110 and the drying upper plate 120, and the plurality of heating blocks 102 can include a first heating block corresponding to the first position and a second heating block corresponding to the second position. The heating temperature of the first heating block can be set to be higher than that of the second heating block, lower than that of the second heating block, or the same as that of the second heating block, according to the progress of the drying process.

[0047] The drying upper plate 120 can be disposed at the upper portion of the stage 100. In the case where the substrate 110 is mounted on the stage 100, the drying upper plate 120 can be disposed at the upper portion of the substrate 110. The drying upper plate 120 can be implemented to be movable up and down to adjust the distance between the drying upper plate 120 and the stage 100 or the substrate 110 mounted on the stage 100, or to be movable left and right to align the drying upper plate 120 with the stage 100 or the substrate 110 mounted on the stage 100, as necessary.

[0048] The drying upper plate 120 can include a plurality of solvent sensors 122. The plurality of solvent sensors 122 can be disposed to contact or be disposed close to a lower surface of the drying upper plate 120, so that the concentration of solvent vapor generated from the substrate 110 can be detected at a plurality of positions between the substrate 110 and the drying upper plate 120. According to a specific implementation purpose, the plurality of solvent sensors 122 can have a hole or a passage through which gas including solvent vapor generated from the ink in the drying chamber 10 can pass, so that the plurality of solvent sensors 122 can be effectively exposed to the solvent vapor, and the plurality of solvent sensors 122 can detect the concentration of the solvent vapor from the gas flowing through the hole or the passage.

[0049] In particular, the plurality of solvent sensors 122 can respectively detect the concentration of the solvent vapor at different respective positions. For example, between the substrate 110 and the drying upper plate 120, the plurality of positions can include a first position and a second position, and the plurality of solvent sensors 122 can include a first solvent sensor for detecting a first concentration of the solvent vapor at the first position and a second solvent sensor for detecting a second concentration of the solvent vapor at the second position.

[0050] The vacuum line 12 is connected to a vacuum pump, and can discharge solvent vapor inside the drying chamber 10 to the outside. In order to flow the solvent vapor, a valve, for example, a throttle valve, can be provided between the vacuum line 12 and the vacuum pump, but the scope of the present application is not limited thereto. In addition, the vacuum pump can be a roughing pump, a roughing pump and a turbo pump, or a roughing pump and a cryogenic pump, and the roughing pump can be a dry pump such as a scroll pump, a diaphragm pump, a screw pump, etc., but the scope of the present application is not limited thereto.

[0051] In the present embodiment, a semiconductor material for configuring various layers such as a display layer, a touch layer, an anti-reflection layer, etc. of a display device can be formed on the substrate 110, but the scope of the present application is not limited thereto, and any semiconductor material for manufacturing any display device can be formed on the substrate 110. Also, it is noted that the embodiments of the present application can be applied to a drying process for a display device to which an inkjet printing method is applied, regardless of what the drying process is applied to. In addition, the scope of the present application covers all processes for manufacturing a thin film using an ink, for example, all processes for manufacturing a printed OLED, a solar cell, a sensor, a QD (quantum dot) filter, etc.

[0052] For the sake of explanation, in the present embodiment, it is assumed that, in order to form a display layer of an organic light emitting display device, a partition wall 112, an insulating film 114 partitioned by the partition wall 112 and forming a pixel, a pixel electrode 116, and a light emitting layer 118 are formed on a substrate 110. However, as described above, the present embodiment can be applied to any substrate on which any ink for a light emitting layer is dropped in an inkjet printing chamber. That is, although a structure in which the insulating film 114 is formed on the entire surface of the substrate 110 and then the partition wall 112 is formed on the insulating film 114 is shown in the above embodiment, the present embodiment can be applied to a structure in which the partition wall 112 is formed on the entire surface of the substrate 110 and then the insulating film 114 is formed on the partition wall 112. Figure 1 Although an example of a display device is shown in the above embodiment, the display device of the present application is not limited thereto, and the display device can have, for example, a structure in which the insulating film 114 is formed on the entire surface of the substrate 110 and then the partition wall 112 is formed on the insulating film 114.

[0053] The substrate 110 can include a plastic so as to have a flexible property, or can be formed of a glass which does not have a flexible property. The substrate 110 including a plastic can include at least one of polystyrene, polyvinyl alcohol, Polymethyl methacrylate, polyethersulfone, polyacrylate, polyetherimide, polyethylenenaphthalate, polyethylene terephthalate, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, triacetate cellulose, and cellulose acetate propionate. In addition, the substrate 110 can further include a flexible material which can be bent or folded, and can be a single layer or a plurality of layers. In addition, a buffer layer, a barrier layer, or the like can be further formed on the substrate 110, but the scope of the present application is not limited thereto.

[0054] In a case where the substrate 110 includes a plastic material, a moving substrate (not shown) formed of a glass or the like can be further included between the heating block 102 of the stage 100 and the substrate 110. The plastic material of the substrate 110 can be prevented from being directly heated to change a property by the moving substrate.

[0055] The insulating film 114, the pixel electrode 116, and the light emitting layer 118 can be included on the substrate 110. The substrate 110 of the present embodiment is a substrate included in an organic light emitting display device, and although not shown, can further include a plurality of transistors which can further include a semiconductor layer, a conductive layer, and an insulating film therebetween.

[0056] The insulating film 114 can be formed to improve the light emitting efficiency of the light emitting layer 118, and can include an organic insulating material such as a general-purpose polymer such as polymethyl methacrylate (PMMA) or polystyrene (PS), a polymer derivative having a phenolic group, an acrylic polymer, an imide polymer, polyimide, an acrylic polymer, a siloxane polymer, etc., but the scope of the present application is not limited thereto.

[0057] The pixel electrode 116 can be formed on the insulating film 114. The pixel electrode 116 can be provided for each pixel, and can include a metal such as silver (Ag), lithium (Li), calcium (Ca), aluminum (Al), magnesium (Mg), gold (Au), and can also include a transparent conductive oxide (TCO) such as indium tin oxide (ITO) and indium zinc oxide (IZO), but the scope of the present application is not limited thereto.

[0058] The pixel can be defined by the partition wall 112. The partition wall 112 can include an organic insulating material such as a general-purpose polymer such as polymethyl methacrylate (PMMA) or polystyrene (PS), a polymer derivative having a phenolic group, an acrylic polymer, an imide polymer, polyimide, an acrylic polymer, a siloxane polymer, etc. The partition wall 112 can include a black dye to be opaque to light.

[0059] The light emitting layer 118 can include a substance layer that inherently emits light of a basic color such as red, green, and blue. In addition, the light emitting layer 118 can also have a structure in which a plurality of substance layers that emit light of different colors are stacked.

[0060] The above has been described based on an organic light emitting display device and with the light emitting layer 118 being an organic substance. However, according to an embodiment, the substrate 110 can be a substrate including a color filter or a color conversion layer in a liquid crystal display device or an organic light emitting display device, and in this case, the light emitting layer 118 can be a color filter layer or a color conversion layer formed of an organic substance. In addition, according to an embodiment, the light emitting layer 118 can be a substance layer including a plurality of organic substances, inorganic substances, quantum dots. Furthermore, the embodiments of the present application can be applied not only to the drying of the light emitting layer, but also to the drying of any layer formed by inkjet, such as an alignment film of a liquid crystal display device, an encapsulation layer of an organic light emitting display device, etc.

[0061] Hereinafter, referring to FIG. 1, a description will be given of an exemplary process performed with respect to the light emitting layer 118, which is a process of dropping ink by an inkjet printing method, drying the ink dropped on the substrate 110, and performing baking. Figures 2 to 5

[0062] Figures 2 to 5 is a diagram for explaining a drying method of an embodiment of the present application.​

[0063] Referring to Figure 2 In the inkjet printing chamber, ink for forming the light emitting layer 118a can be dropped onto the substrate 110 on which the insulating film 114 and the pixel electrode 116 are formed. Specifically, the dropping device 14 can apply the ink on the substrate 110 by dropping the ink to the pixel region defined by the partition wall 112. Of course, the other layers 114, 116 can also be formed in the same or similar manner as the light emitting layer 118a.

[0064] Inside the inkjet printing chamber, in order to drop the ink, a stage for mounting the substrate 110, the dropping device 14 including an inkjet head having at least one nozzle, and an alignment sensor for aligning the dropping device 14, etc. can be provided. Further, a transfer device for moving the dropping device 14 to a desired position can also be provided inside the inkjet printing chamber.

[0065] In addition, as a solvent of the light emitting layer ink dropped by the dropping device 14 onto the substrate 110, an organic solvent such as mesitylen, tetralin, or cyclohexanone can be used, but the scope of the present application is not limited thereto, and various solvents capable of bringing an arbitrary influence to the light emitting layer ink can be used.

[0066] Next, referring to Figure 3 The substrate 110 on which the ink dropping process is completed can be transported out of the inkjet printing chamber and into the drying chamber 10. In Figure 2 and Figure 3 The light emitting layer 118a contains the solvent, and the solvent of the light emitting layer 118a can be removed in the subsequent drying process.

[0067] Next, referring to Figure 4 As the drying process is performed in the drying chamber 10, the solvent vapor is generated from the light emitting layer 118b. The solvent vapor generated from the light emitting layer 118b can move in the direction of the drying upper plate 120 along the path indicated by the arrow in Figure 4 After passing through the passages in the left and right side directions of the substrate 110, the solvent vapor is discharged to the outside through the vacuum pipe 12 of the lower portion of the stage 100. The vacuum pump connected to the vacuum pipe 12 can facilitate the discharge of the solvent vapor.

[0068] In this process, the concentration of the solvent vapor can be different depending on the position between the substrate 110 and the drying upper plate 120. That is, the concentration distribution of the solvent vapor can be non-uniform in the left and right directions of Figure 4 .

[0069] The factors that cause the concentration of the solvent vapor to be unevenly distributed can be various. For example, the following can be listed: a case where the speed of the vacuuming in the drying process is slower than the speed of the generation of the solvent vapor from the substrate 110, a case where the solvent vapor moves slowly between the drying upper plate 120 and the substrate 110 for some reason, and a case where a part of the light-emitting layer 118b reabsorbs the solvent vapor because the interval between the drying upper plate 120 and the substrate 110 is narrow, and the like. Thus, a difference can occur in the drying speed of the light-emitting layer 118b, and the drying profile of the light-emitting layer 118b can differ, and the thickness of the light-emitting layer 118b can be unevenly formed.

[0070] For example, in the case of the drying of the light-emitting layer 118b in the central region (hereinafter referred to as the "center region") of the substrate 110, the drying speed of the light-emitting layer 118b can be slower than the drying speed of the light-emitting layer 118b in the edge regions (hereinafter referred to as the "edge regions") of the substrate 110. That is, the drying of the center region can occur at a slower speed than the drying of the edge regions. Thus, the drying profile of the light-emitting layer 118b in the center region and the drying profile of the light-emitting layer 118b in the edge regions can differ. Figure 4

[0071] In order to prevent or minimize such unevenness, the plurality of solvent sensors 122a, 122b can detect the concentration of the solvent vapor at a first position (for example, the edge region) and a second position (for example, the center region). That is, the first solvent sensor 122a can detect a first concentration of the solvent vapor in the edge region, and the second solvent sensor 122b can detect a second concentration of the solvent vapor in the center region.

[0072] The plurality of solvent sensors 122a, 122b can also detect the concentration of the solvent vapor at any time during the drying process, at predetermined time intervals, or in a predetermined time pattern. Of course, the plurality of solvent sensors 122a, 122b can also detect the concentration of the solvent vapor in real time.

[0073] The concentration data of the solvent vapor by position thus collected by the plurality of solvent sensors 122a, 122b can be analyzed and applied to process improvement. For example, based on the collected concentration data of the solvent vapor, the drying profile of the light-emitting layer 118b in the entire region can be made uniform in various ways such as adjusting the speed of the vacuum pump, adjusting the interval between the drying upper plate 120 and the substrate 110, or adjusting the temperature of the stage 100, and the like.

[0074] ​In particular, as a result of analyzing the concentration data of the solvent vapor by position collected by the plurality of solvent sensors 122a, 122b, in a case where the drying speed of the light emitting layer 118b at a position adjacent to the second solvent sensor 122b differs from the drying speed of the light emitting layer 118b at a position adjacent to the first solvent sensor 122a by a prescribed range or more, the plurality of heating blocks 102a, 102b can be used to enhance the slow drying speed.

[0075] Specifically, the plurality of heating blocks 102a, 102b can heat the substrate 110 at a suitable temperature that promotes drying, and can include a first heating block 102a corresponding to a first position and a second heating block 102b corresponding to a second position that are independently operated from each other.

[0076] For example, in a case where the first concentration is higher than the second concentration, the heating temperature of the first heating block 102a can be set to be higher than the heating temperature of the second heating block 102b. Thereby, at a position adjacent to the first heating block 102a, the emission of the solvent vapor of the light emitting layer 118b is more active, and thus the drying speed can be relatively increased. Conversely, in a case where the first concentration is lower than the second concentration, the heating speed of the first heating block 102a can be set to be lower than the heating temperature of the second heating block 102b. Thereby, at a position adjacent to the second heating block 102b, the emission of the solvent vapor of the light emitting layer 118b is more active, and thus the drying speed can be relatively increased.

[0077] In this way, by providing the plurality of solvent sensors 122a, 122b on the drying upper plate 120 and detecting the concentration distribution of the solvent vapor inside the drying chamber 10 in real time, it is possible to detect the difference in the drying speed by position of the substrate 110, and for example, it is possible to locally control the drying speed of a position where the difference is large using the plurality of heating blocks 102a, 102b that can set the heating temperature respectively, thereby uniformly forming the thickness of the light emitting layer.

[0078] Next, referring to Figure 5 A baking process can be performed on the substrate 110 on which the drying process is completed. For the baking process, the substrate 110 is heated from room temperature to a maximum temperature of about 250°C to about 350°C after being transported into a baking chamber provided with a heater 16. After the baking process is completed, as shown in FIG. 1C, the light emitting layer 118c can have a profile of a shape in which the upper surface is flat. Figure 5

[0079] Figures 6 to 8 is a diagram of a drying upper plate for explaining an embodiment of the present application.

[0080] Referring to Figure 6 ​On the drying upper plate 120A of an embodiment of the present application, a plurality of solvent sensors including a solvent sensor 122A can be provided in an X shape. Referring to Figure 7 On the drying upper plate 120B of another embodiment of the present application, a plurality of solvent sensors including a solvent sensor 122B can be provided along diagonal lines. Also, referring to Figure 8 On the drying upper plate 120C of still another embodiment of the present application, a plurality of solvent sensors including a solvent sensor 122C can be provided in a cross shape.

[0081] Of course, Figures 6 to 8 The illustrated arrangement forms of the solvent sensors are only exemplary, and the scope of the present application is not limited thereto. The solvent sensors of the drying upper plate can be implemented in any arrangement form capable of efficiently and accurately controlling the drying speed so as to uniformly form the thickness of the light emitting layer.

[0082] Figures 9 to 11 is a diagram for explaining a stage of an embodiment of the present application.

[0083] Referring to Figure 9 On the stage 100A of an embodiment of the present application, a plurality of heating blocks including a heating block 102A can be provided in an array shape. Referring to Figure 10 On the stage 100B of another embodiment of the present application, a plurality of heating blocks including a heating block 102B can be provided in a concentric quadrilateral shape. Also, referring to Figure 11 On the stage 100C of still another embodiment of the present application, a plurality of heating blocks including a heating block 102C can be provided in a concentric circular shape. At least two of the plurality of heating blocks can be implemented to be independently operated, respectively, or to be simultaneously operated together.

[0084] Of course, Figures 9 to 11 The illustrated arrangement forms of the heating blocks are only exemplary, and the scope of the present application is not limited thereto. The heating blocks of the stage can be implemented in any arrangement form capable of setting a heating temperature accurately controlled at a desired position of the substrate.

[0085] Figure 12 is a diagram for explaining a drying apparatus of an embodiment of the present application.

[0086] Referring to Figure 12 The drying apparatus 2 of an embodiment of the present application can include a drying chamber 10, a vacuum line 12, and a drying speed control apparatus 20. Detailed contents regarding the drying chamber 10 and the vacuum line 12 can be referred to the contents explained in the foregoing with reference to Figures 1 to 5 The detailed contents regarding the drying chamber 10 and the vacuum line 12 can be referred to the contents explained in the foregoing with reference to

[0087] The drying speed control device 20 can be configured to adjust the drying speed of the substrate 110 by controlling the heating temperature of the plurality of heating blocks 102a, 102b according to the concentrations measured by the plurality of solvent sensors 122a, 122b.

[0088] For example, the first solvent sensor 122a detects a first concentration of solvent vapor at a first position, the second solvent sensor 122b detects a second concentration of solvent vapor at a second position, the first heating block 102a corresponds to the first position, the second heating block 102b corresponds to the second position, and in the case where the first concentration is higher than the second concentration, the drying speed control device 20 can be set to have a higher heating temperature for the first heating block 102a than for the second heating block 102b. Conversely, in the case where the first concentration is lower than the second concentration, the drying speed control device 20 can be set to have a lower heating temperature for the first heating block 102a than for the second heating block 102b.

[0089] To this end, in the present embodiment, the drying speed control device 20 can include at least a first interface for receiving concentration data detected by the plurality of solvent sensors 122a, 122b and a second interface for transmitting instructions for setting the heating temperature of the plurality of heating blocks 102a, 102b, and the drying speed control device 20 can be implemented by an electronic device having a processor that receives input of the concentration data detected by the plurality of solvent sensors 122a, 122b and calculates the heating temperature of the plurality of heating blocks 102a, 102b. Of course, the scope of the present application is not limited thereto, and the drying speed control device 20 can also be implemented by other hardware including some or all of the aforementioned structures, by a combination of hardware and software that performs some or all of the above functions, or by software that performs some or all of the above functions alone.

[0090] Figure 13 is a flowchart of a drying method for explaining an embodiment of the present application.

[0091] Referring to Figure 13 , the drying method of an embodiment of the present application can include a step S1301 of providing a substrate 110 to a stage 100 including a plurality of heating blocks 102a, 102b, and a step S1303 of providing a drying upper plate 120 including a plurality of solvent sensors 122a, 122b to an upper portion of the stage 100.

[0092] Here, the stage 100 and the drying upper plate 120 can be provided to be respectively movable up and down so as to adjust the distance therebetween. In addition, more detailed contents regarding the stage 100 and the drying upper plate 120 can be referred to the foregoing description.

[0093] Further, the drying method can further include a step S1305 of detecting a concentration of the solvent vapor generated from the substrate 110 at a plurality of positions using a plurality of solvent sensors 122a, 122b.

[0094] Here, the plurality of solvent sensors 122a, 122b can have a hole or a passage through which a gas including the solvent vapor generated from the ink in the drying chamber 10 passes so as to effectively expose the plurality of solvent sensors 122a, 122b to the solvent vapor, and the plurality of solvent sensors 122a, 122b can detect the concentration of the solvent vapor from the gas flowing through the hole or the passage. Further, more detailed contents regarding the plurality of solvent sensors 122a, 122b can be referred to the foregoing description.

[0095] Further, the drying method can further include a step S1307 of controlling a heating temperature of the plurality of heating blocks 102a, 102b according to the concentration measured by the plurality of solvent sensors 122a, 122b, thereby adjusting a drying speed of the substrate 110.

[0096] Here, the plurality of heating blocks 102a, 102b can be set such that the heating blocks corresponding to different positions can have different heating temperatures, respectively. Further, more detailed contents regarding the plurality of heating blocks 102a, 102b can be referred to the foregoing description.

[0097] Here, the plurality of positions include a first position and a second position, the plurality of solvent sensors 122a, 122b include a first solvent sensor 122a for detecting a first concentration of the solvent vapor at the first position and a second solvent sensor 122b for detecting a second concentration of the solvent vapor at the second position, and the plurality of heating blocks 102a, 102b include a first heating block 102a corresponding to the first position and a second heating block 102b corresponding to the second position. In a case where the first concentration is higher than the second concentration, the step of adjusting the drying speed can include a step of setting such that a heating temperature of the first heating block 102a is higher than a heating temperature of the second heating block 102b.

[0098] Differently from this, in a case where the first concentration is lower than the second concentration, the step of adjusting the drying speed can include a step of setting such that the heating temperature of the first heating block 102a is lower than the heating temperature of the second heating block 102b.

[0099] In addition, the step of adjusting the drying speed can include a step of detecting the concentration and controlling the heating temperature according to a predetermined time pattern. Furthermore, the step of adjusting the drying speed can include a step of detecting the concentration and controlling the heating temperature at an arbitrary time, or a step of controlling the heating temperature at a predetermined time interval. Of course, the step of adjusting the drying speed can include a step of detecting the concentration and controlling the heating temperature in real time.

[0100] According to the embodiment of the present application described so far, by providing a plurality of solvent sensors on the drying upper plate and detecting the concentration distribution of the solvent vapor inside the drying chamber in real time, the difference in the drying speed of the substrate by position can be detected, and by locally controlling the drying speed of the position where the difference is large, the thickness of the light emitting layer can be uniformly formed.

[0101] Further, according to the embodiment of the present application, the drying speed control device is provided, which controls the heating temperature of the plurality of heating blocks according to the concentration measured by the plurality of solvent sensors, thereby adjusting the drying speed of the substrate, so that the adjustment of the drying speed and the thickness of the light emitting layer can be automatically performed.

[0102] The above has described the embodiment of the present application in detail, but the scope of the right of the present application is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present application defined in the appended claims also belong to the scope of the right of the present application.

[0103] Explanation of Reference Numerals

[0104] 1, 2: Drying device 10: Drying chamber

[0105] 100: Stage 102: Heating block

[0106] 110: Substrate 112: Partition wall

[0107] 114: Insulating film 116: Pixel electrode

[0108] 118: Light emitting layer 120: Drying upper plate

[0109] 122: Solvent sensor 12: Vacuum line

[0110] 14: Dropping device 16: Heater

Claims

1. A drying apparatus comprising: a stage for supporting a substrate, and including a plurality of heating blocks for heating the substrate; and a drying upper plate provided at an upper portion of the stage, and including a plurality of solvent sensors for detecting a concentration of solvent vapor generated from the substrate at a plurality of positions, the plurality of positions including a first position and a second position, the plurality of solvent sensors including a first solvent sensor for detecting a first concentration of the solvent vapor at the first position; and a second solvent sensor for detecting a second concentration of the solvent vapor at the second position, the plurality of heating blocks including a first heating block corresponding to the first position and a second heating block corresponding to the second position.

2. The drying apparatus according to claim 1, wherein in a case where the first concentration is higher than the second concentration, a heating temperature of the first heating block is set to be higher than a heating temperature of the second heating block.

3. The drying apparatus according to claim 1, wherein in a case where the first concentration is lower than the second concentration, a heating temperature of the first heating block is set to be lower than a heating temperature of the second heating block.

4. The drying apparatus according to claim 1, wherein the plurality of solvent sensors are provided on the drying upper plate in a diagonal line, or in an X shape, or in a cross shape.

5. The drying apparatus according to claim 1, wherein the plurality of heating blocks are provided on the stage in an array shape, or in a concentric quadrilateral shape, or in a concentric circular shape.

6. The drying apparatus according to claim 1, further comprising a vacuum line connected to a vacuum pump to exhaust the solvent vapor.

7. A drying apparatus comprising: a plurality of heating blocks for heating a substrate; a plurality of solvent sensors for detecting a concentration of solvent vapor generated from the substrate at a plurality of positions; and a drying speed control device for controlling a heating temperature of the plurality of heating blocks in accordance with the concentration measured by the plurality of solvent sensors, thereby adjusting a drying speed of the substrate, the plurality of positions including a first position and a second position, the plurality of solvent sensors including a first solvent sensor for detecting a first concentration of the solvent vapor at the first position; and a second solvent sensor for detecting a second concentration of the solvent vapor at the second position, the plurality of heating blocks including a first heating block corresponding to the first position and a second heating block corresponding to the second position.

8. The drying apparatus according to claim 7, wherein in a case where the first concentration is higher than the second concentration, the drying speed control device is set so that a heating temperature of the first heating block is higher than a heating temperature of the second heating block, in a case where the first concentration is lower than the second concentration, the drying speed control device is set so that a heating temperature of the first heating block is lower than a heating temperature of the second heating block.

9. The drying apparatus according to claim 7, wherein ​ ​ ​ ​ The drying speed control device includes a first interface for receiving concentration data detected by the plurality of solvent sensors and a second interface for transmitting an instruction for setting a heating temperature of the plurality of heating blocks, The drying speed control device includes a processor that receives an input of concentration data detected by the plurality of solvent sensors and calculates a heating temperature of the plurality of heating blocks.

10. The drying apparatus of claim 7, Further comprising a vacuum line connected to a vacuum pump to exhaust the solvent vapor.

11. A drying method, comprising the steps of: providing a substrate to a stage including a plurality of heating blocks; providing a drying upper plate including a plurality of solvent sensors to an upper portion of the stage; detecting a concentration of a solvent vapor generated from the substrate at a plurality of positions using the plurality of solvent sensors; and controlling a heating temperature of the plurality of heating blocks according to the concentration measured by the plurality of solvent sensors, thereby adjusting a drying speed of the substrate, the plurality of positions include a first position and a second position, the plurality of solvent sensors include a first solvent sensor for detecting a first concentration of the solvent vapor at the first position; and a second solvent sensor for detecting a second concentration of the solvent vapor at the second position, the plurality of heating blocks include a first heating block corresponding to the first position and a second heating block corresponding to the second position.

12. The drying method of claim 11, wherein, in a case where the first concentration is higher than the second concentration, the step of adjusting the drying speed includes a step of setting the heating temperature of the first heating block to be higher than the heating temperature of the second heating block, in a case where the first concentration is lower than the second concentration, the step of adjusting the drying speed includes a step of setting the heating temperature of the first heating block to be lower than the heating temperature of the second heating block.

13. The drying method of claim 11, wherein, the step of adjusting the drying speed includes a step of detecting the concentration and controlling the heating temperature according to a pre-set time pattern. ​

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