Coating device and coating method

Abstract

To provide a coating device which can suppress formation of coating irregularity and form a coated film of a uniform thickness even when a foreign matter exists between a stage and a substrate.SOLUTION: A coating device includes: a stage on which a substrate is mounted; and a coating unit which ejects coating liquid while moving relatively in one direction with respect to the substrate mounted on the surface of the stage and thereby forms a coating film on the substrate. The stage has an exclusion area holding part which sucks and holds an exclusion area other than a coating area of the substrate on which the coating film is formed and a coating area holding part which sucks and holds the coating area. The exclusion area holding part is provided so as to surround the coating area and is formed so that the substrate can be held on the stage while the coating area holding part is released.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a coating apparatus that forms a coating film on a substrate by relatively moving a coating unit that ejects a coating liquid and the substrate. [Background technology]

[0002] In flat panel displays such as liquid crystal displays and organic electroluminescence displays, a substrate made of glass is used that has been coated with a coating liquid such as a resist liquid (called a coated substrate). This coated substrate is formed by a coating device that uniformly coats the coating liquid. This coating device has a stage for placing the substrate and a coating unit that ejects the coating liquid, and while ejecting the coating liquid from a slit nozzle of the coating unit, the substrate and the coating unit are moved relatively in one direction to form a substrate on which a coating film of uniform thickness is formed.

[0003] The stage of this coating device is configured to hold the substrate by suction on the mounting surface on which the substrate is placed. Specifically, as shown in FIG. 8, suction grooves 102 are formed in a lattice pattern on the entire mounting surface 101 of the stage 100, and suction holes 103 formed in the suction grooves 102 are connected to a vacuum pump 104. When the vacuum pump 104 is operated with the substrate W placed on the mounting surface 101, a suction force is generated in the entire suction grooves 102 through the suction holes 103, and the substrate W can be suctioned and held on the mounting surface 101. That is, the entire substrate W is held in a state in which it maintains a horizontal posture along the mounting surface 101 of the stage 100. A coating liquid is applied in this state, so that a coating film of uniform thickness is formed on the substrate W (see, for example, Patent Document 1 below). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2012-250206 A Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, not only glass but also a film thinner and more flexible than glass is used as the substrate W, and it is required to form a coating film of uniform thickness on the substrate W formed of this film. However, if a foreign object P exists on the mounting surface 101 of the stage 100 for some reason, there is a problem that it is difficult to form a coating film of uniform thickness. That is, if a foreign object P exists on the mounting surface 101 of the stage 100, the substrate W is placed on the mounting surface 101 as it is (FIG. 9(a)) and the vacuum pump 104 is operated to adsorb the foreign object P, as shown in FIG. 9(b), the substrate W is sucked by a strong suction force, and the substrate W at the portion where the foreign object P exists adheres to the foreign object P and deforms according to the shape of the foreign object P. If a coating film is formed in this state, there is a problem that the portion where the foreign object P exists is not flat but is sharply deformed, so that coating unevenness is formed in that portion, and the uniformity of the coating film formed on the substrate W is impaired.

[0006] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a coating apparatus that can suppress the formation of uneven coating and form a coating film of uniform thickness even when foreign matter is present between the stage and the substrate. [Means for solving the problem]

[0007] In order to solve the above problems, a coating apparatus of the present invention is a coating apparatus including a stage for placing a substrate, and a coating unit for forming a coating film on the substrate by discharging a coating liquid while moving in one direction relative to the substrate placed on a surface of the stage, the stage having a coating region holding section for sucking and holding a coating region where a coating film that requires product precision is to be formed, and an exclusion region holding section for sucking and holding an exclusion region where product precision is not required for the formed coating film, the exclusion region holding section being provided to surround the coating region and being formed so as to be able to hold the substrate on the stage when the coating region holding section is released. the exclusion region holding portion and the coating region holding portion are formed with suction holes which generate a suction force and suction grooves which communicate with the suction holes and open to the surface of the stage, the suction grooves of the exclusion region holding portion and the suction grooves of the coating region holding portion are formed discontinuously, the exclusion region holding portion has a suction pad which is embedded in the stage separately from the suction holes and the suction grooves, the suction pad is formed so as to be displaceable between a standby position in which it protrudes from the surface of the stage and a suction position in which it is accommodated within the stage, and after the entire substrate is suction-held by the coating region holding portion and the exclusion region holding portion, when the coating region holding portion is released while the suction of the exclusion region holding portion is maintained, the suction of the coating region holding portion is released by forcibly supplying air. It is characterized by the following.

[0008] According to the coating device, the exclusion area holding part is provided so as to surround the coating area, and the substrate can be held in a state where the coating area holding part is released, so that coating unevenness can be suppressed even when a foreign object is present between the stage and the substrate. That is, when the entire substrate is sucked and held by the coating area holding part and the exclusion area holding part, if a foreign object is present on the stage, the portion where the foreign object is present adheres to the foreign object and deforms sharply to conform to the foreign object. Then, when the coating area holding part is released while the suction of the exclusion area holding part is maintained, the coating area of ​​the substrate is released from the adhesion of the foreign object, and the sharp deformation of the substrate is alleviated, so that the portion where the foreign object is present becomes nearly flat while maintaining the state where the exclusion area is adsorbed and held. When a coating film is formed in this state, even when a foreign object is present, the deformation of the substrate in that portion is gentle, so that coating unevenness is not noticeable, and a uniform coating film can be formed overall. In addition, since the suction grooves of the coating area holding part and the exclusion area holding part are formed discontinuously, they can be operated independently. Therefore, after the coating area holding part and the exclusion area holding part hold the substrate by suction, only the coating area holding part can be released and the substrate can be suction-held only by the exclusion area holding part. Even if the substrate is warped and the exclusion area of ​​the substrate is raised above the stage, the substrate can be suctioned by the suction pad in the standby position protruding from the surface of the stage, and as a result of the suction, the suction pad contracts and displaces to the suction position in which the substrate is accommodated within the stage, so that even a warped substrate can be held on the stage.

[0013] In order to solve the above problems, the coating method of the present invention is a coating method in a coating apparatus including a stage for placing a substrate, and a coating unit for forming a coating film on the substrate by discharging a coating liquid while moving in one direction relative to the substrate placed on the surface of the stage, the method including a coating area holding step of suctioning and holding a coating area of ​​the substrate on which a coating film requiring product precision is to be formed, an exclusion area holding step of suctioning and holding an exclusion area of ​​the formed coating film on which product precision is not required, and a coating area release step of releasing the coating area from its held state, the exclusion area holding portion and the application area holding portion are formed with a suction hole which generates a suction force and a suction groove which communicates with the suction hole and opens onto the surface of the stage, the suction groove of the exclusion area holding portion and the suction groove of the application area holding portion are formed discontinuously, the exclusion area holding portion has a suction pad which is embedded within the stage separately from the suction hole and the suction groove, and the suction pad is formed to be displaceable between a standby position in which it protrudes from the surface of the stage and an adsorption position in which it is accommodated within the stage, By carrying out the coating area holding step and the exclusion area holding step, the substrate is held on the surface of the stage, and then, by carrying out the coating area releasing step, a coating film is formed on the substrate in a state in which the holding state of the coating area is released. After the entire substrate is suction-held by the coating region holding step and the exclusion region holding step, when the coating region holding is released while the suction of the exclusion region holding part is maintained, the suction of the coating region holding part is released by forcibly supplying air. It is characterized by the following.

[0014] According to the above coating method, the coating area holding step and the exclusion area holding step are performed to hold the substrate on the surface of the stage, and then the coating area releasing step is performed to prevent coating unevenness from being formed even if a foreign object is present between the stage and the substrate. That is, when the entire substrate is sucked and held by suction in the coating area holding step and the exclusion area holding step, if a foreign object is present on the stage, the portion where the foreign object is present adheres to the foreign object and deforms sharply to fit the foreign object. Then, the coating area releasing step is performed, and the adhesion to the foreign object is released, and the sharp deformation of the substrate is alleviated, so that the portion where the foreign object is present becomes nearly flat. When a coating film is formed in this state, even if a foreign object is present, the deformation of the substrate in that portion is gentle, so that coating unevenness is not noticeable, and a uniform coating film can be formed overall.

[0015] In addition, the coating area holding process and the exclusion area holding process may be configured to adsorb and hold a predetermined area of ​​the substrate on the surface of the stage, at least on the side where the coating unit enters, and then the coating unit enters the substrate and a coating film is formed.

[0016] According to this configuration, when a predetermined area of ​​the substrate on the side where the coating unit enters is adsorbed and held, the coating unit enters onto the substrate and begins coating, thereby shortening the takt time for forming a coating film. Effect of the Invention

[0017] According to the coating apparatus of the present invention, even if a foreign object is present between the stage and the substrate, the formation of uneven coating can be suppressed and a coating film of uniform thickness can be formed. [Brief description of the drawings]

[0018] [Figure 1] 1 is a perspective view showing a schematic external appearance of a coating device according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a diagram showing a stage in the coating apparatus. [Diagram 3] 4A and 4B are diagrams showing an suction pad in the coating apparatus, in which (a) shows the suction pad in a standby position, and (b) shows the suction pad in a suction position. [Figure 4] 5 is a flowchart showing a substrate holding operation of the coating apparatus. [Diagram 5] 4 is a flowchart showing a coating process operation of the coating device. [Figure 6] 1A is a schematic diagram showing the state of a substrate loaded onto the stage, where (a) shows the state where the loaded substrate is received by lift pins, (b) shows the state where substrates are being placed in order from the coating start side, and (c) shows the state where suction holding of area 1 has been completed and coating preparation operation is being performed. [Figure 7] 1A is a schematic diagram showing the state of a substrate brought into a stage, in which (a) shows the state in which the entire substrate is adsorbed and held by the exclusion area holding section and the coating area holding section, (b) shows the state in which the coating area holding section has been released and the substrate is adsorbed and held only by the exclusion area, and (c) shows the state in (b) in which formation of a coating film has been completed. [Figure 8]FIG. 1 is a diagram showing a stage in a conventional coating apparatus. [Figure 9] 1A and 1B are diagrams showing a film substrate held on a conventional stage, where (a) shows the state before suction force is generated, and (b) shows the state after suction force is generated. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] FIG. 1 is a perspective view that illustrates a schematic appearance of a coating device according to one embodiment of the present invention.

[0020] The coating apparatus 1 forms a coating film M of a liquid material (hereinafter referred to as coating liquid) such as a chemical liquid or a resist liquid on a substrate W, and includes a base 2, a stage 21 for placing the substrate W on the stage 21, and a coating unit 30 configured to be movable in a specific direction relative to the stage 21. When the substrate W is supplied to the stage 21, the coating unit 30 moves over the substrate W, and the coating liquid is discharged from the coating unit 30 to form a coating film M of uniform thickness on the substrate W.

[0021] In the following explanation, the direction in which the coating unit 30 moves (coating direction) is the X-axis direction, the direction perpendicular to this on the horizontal plane is the Y-axis direction, and the direction perpendicular to both the X-axis and Y-axis directions is the Z-axis direction.

[0022] The substrate W in this embodiment is a rectangular substrate having a thickness of about 0.01 to 0.5 mm. The substrate W is made of, for example, glass, a film, or the like, and has flexibility.

[0023] The coating unit 30 ejects a coating liquid onto the substrate W to form a coating film M. As shown in FIG. 1, the coating unit 30 has legs 31 connected to the base 2 and a nozzle 34 extending in the Y-axis direction, and is attached to the base 2 so as to be movable in the X-axis direction while straddling the base 2 in the Y-axis direction. Specifically, rails 22 extending in the X-axis direction are provided on both ends of the base 2 in the Y-axis direction, and the legs 31 are attached to the rails 22 so as to be slidable. A linear motor 33 is attached to the legs 31, and the coating unit 30 can be moved in the X-axis direction and stopped at any position by controlling the driving of the linear motor 33.

[0024] Further, a nozzle part 34 for applying the coating liquid is attached to the leg part 31 of the coating unit 30. Specifically, the leg part 31 is provided with a rail 37 extending in the Z-axis direction and a slider 35 sliding along the rail 37, and the slider 35 and the nozzle part 34 are connected. A ball screw mechanism driven by a servo motor is attached to the slider 35, and the slider 35 can be moved in the Z-axis direction and stopped at any position by controlling the drive of the servo motor. That is, the nozzle part 34 is supported so as to be able to approach and separate from the substrate W held by the stage 21.

[0025] The nozzle 34 ejects the coating liquid to form a coating film M on the substrate W. The nozzle 34 is a columnar member having a shape extending in one direction, and is provided so as to extend in the Y-axis direction, which is substantially perpendicular to the traveling direction (X-axis direction) of the coating unit 30. A slit nozzle extending in the longitudinal direction is formed on the surface of the nozzle 34 facing the stage 21, so that the coating liquid supplied to the nozzle 34 is ejected uniformly from the slit nozzle in the longitudinal direction. Therefore, by causing the coating unit 30 to travel in the X-axis direction while ejecting the coating liquid from the slit nozzle, a coating film M of a constant thickness is formed on the substrate W in the longitudinal direction of the slit nozzle.

[0026] A stage 21 is disposed in the center of the base 2. The carried-in substrate W is placed on this stage 21. The stage 21 is formed in a rectangular parallelepiped shape made of stone, and a mounting surface 21a (the surface of the stage 21) on which the substrate W is placed is formed to be substantially flat.

[0027] The stage 21 is provided with a substrate lifting mechanism for lifting and lowering the substrate W that is supplied. Specifically, a plurality of pin holes 41 are formed in the mounting surface 21a of the stage 21, and the lift pins 25 that can be lifted and lowered in the Z-axis direction are embedded in the pin holes 41. That is, when the substrate W is carried in with the lift pins 25 protruding from the surface of the stage 21 (see FIG. 6(a)), the tip portions of the lift pins 25 come into contact with the substrate W to hold the substrate W. Then, the lift pins 25 are lowered from that state to be accommodated in the pin holes 41, so that the substrate W can be mounted on the mounting surface 21a of the stage 21. In this embodiment, the lift pins 25 are set to be accommodated in the direction of coating in order from the coating start side (left side in FIG. 2). That is, the substrate W supported by the lift pins 25 is not placed in its entirety at once, but is placed on the mounting surface 21a in order from the coating start side by accommodating the lift pins 25 (see FIG. 6(b)).

[0028] Further, the stage 21 is provided with a substrate holding means 5 (see FIG. 2), and the substrate W is held by the substrate holding means 5. The substrate holding means 5 has a coating area holding part 50 and an exclusion area holding part 60. Here, the substrate W is provided with a coating area C in which a coating film M that is effective as a product in terms of precision is formed, and an exclusion area E in which the coating film M does not require precision as a product in terms of precision, and the exclusion area E is provided to surround the coating area C. In this embodiment, the coating area C is set in a rectangular shape in the central part of the substrate W, and the exclusion area E is set to cover the entire circumference of the coating area C via the blocking flat part 24. That is, the coating area holding part 50 is for holding the coating area C, and the exclusion area holding part 60 is for holding the exclusion area E. The stage 21 is divided into areas in the coating direction, and in the example of FIG. 2, the areas are set to area 1, area 2, and area 3 in order from the coating start side. That is, areas 1 to 3 are set to include a part of the exclusion area holding section 60 and a part of the coating area holding section 50, respectively, so that a suction force can be generated in each of areas 1 to 3 to hold the substrate W.

[0029] The coating area holding part 50 is provided in the center of the stage 21, that is, in an area corresponding to an area where a coating film M is formed when the substrate W is placed on the stage 21. In the example of Fig. 2, it is formed in a rectangular shape in the center of the stage 21. As a result, when the substrate W is placed on the stage 21 such that the coating area C of the substrate W is located at the coating area holding part 50, a suction force is generated in the coating area holding part 50, and the coating area C of the substrate W is attracted and held.

[0030] The coating region holding section 50 has a suction section 51 that suctions and holds the substrate W. Specifically, the suction section 51 has suction grooves 52 and suction holes 53 formed on the mounting surface 21a of the stage 21, and is capable of generating a suction force by the suction grooves 52 and suction holes 53 to hold the substrate W on the mounting surface 21a. That is, on the mounting surface 21a of the stage 21, suction grooves 52 formed to a predetermined depth are arranged side by side at approximately equal intervals in the X-axis direction and the Y-axis direction, and are arranged in a lattice pattern so as to intersect with each other.

[0031] In addition, at the intersections of the suction grooves 52, suction holes 53 having a diameter larger than the width of the suction grooves 52 are provided, and the suction holes 53 are connected to a suction and exhaust unit such as a vacuum pump 54 and a compressor 55 through a pipe 56. When an intake valve 57 provided in the pipe 56 is opened, a suction force is generated in the suction holes 53, and the suction force is generated throughout the suction grooves 52. When a compressed air valve 58 provided in the pipe 56 is opened, air is supplied to the suction holes 53, and the suction force of the suction grooves 52 is released (suction destruction). As a result, when the compressed air valve 58 is closed and the intake valve 57 is opened with the substrate W placed on the mounting surface 21a of the stage 21, a suction force is generated throughout the suction grooves 52, and the coating area C of the substrate W is suctioned and held on the mounting surface 21a. Then, when the intake valve 57 is closed and the compressed air valve 58 is opened from this state, air is supplied between the mounting surface 21a and the substrate W, releasing the suction force of the suction groove 52 and releasing the held substrate W from the mounting surface 21a. That is, the coating area holding part 50 fixedly holds the coating area C of the placed substrate W by suction, and the suction force is released by supplying air, thereby releasing the suction state of the coating area C.

[0032] In this embodiment, a suction force can be generated for each of areas 1 to 3. That is, the suction holes 53 are arranged in each of areas 1 to 3. In the example of FIG. 2, two suction holes 53 are arranged in each of areas 1 and 3, and four suction holes 53 are arranged in area 2. The piping 56 is provided with valves 59a, 59b, and 59c, and suction forces can be generated and released for each of areas 1 to 3 by switching the valves 59a to 59c. That is, the valve 59a can switch a communication state with the suction hole 53 in area 1, the valve 59b can switch a communication state with the suction hole 53 in area 2, and the valve 59c can switch a communication state with the suction hole 53 in area 3. Therefore, for example, when the vacuum pump 54 is operated with the valve 59a open and the valves 59b and 59c closed, a suction force can be generated only on the application area holding portion 50 of area 1, and when the compressor 55 is operated, the suction force is released only on the application area holding portion 50 of area 1.

[0033] The exclusion region holding part 60 is provided in a portion of the stage 21 excluding the coating region holding part 50. In the example of Fig. 2, the exclusion region holding part 60 is provided outside the coating region holding part 50 so as to surround the coating region holding part 50. In other words, when the substrate W is placed on the stage 21, the exclusion region E of the substrate W is positioned in the exclusion region holding part 60, and the exclusion region E of the substrate W is held by the exclusion region holding part 60.

[0034] Like the coating region holding part 50, the exclusion region holding part 60 has a suction part 61 that adsorbs and holds the substrate W. Specifically, the suction part 61 has suction grooves 62 and suction holes 63 formed on the mounting surface 21a of the stage 21, and in this embodiment, is uniformly arranged so as to surround the coating region holding part 50.

[0035] The suction section 61 is configured to generate a suction force in the suction grooves 62 and the suction holes 63 to hold the substrate W on the mounting surface 21a. That is, on the mounting surface 21a of the stage 21, suction grooves 62 formed to a predetermined depth are arranged side by side at approximately equal intervals in the X-axis and Y-axis directions, and are arranged in a lattice pattern so as to intersect with each other.

[0036] In addition, at the intersections of the suction grooves 62, suction holes 63 having a diameter larger than the width of the suction grooves 62 are provided, and the suction holes 63 are connected to suction and exhaust units such as a vacuum pump 64 and a compressor 65 through piping 66. When an intake valve 67 provided in the piping 66 is opened, a suction force is generated in the suction holes 63, and the suction force is generated throughout the suction grooves 62. When a compressed air valve 68 provided in the piping 66 is opened, air is supplied to the suction holes 63, and the suction force of the suction grooves 62 is released (suction destruction). As a result, when the compressed air valve 68 is closed and the intake valve 67 is opened with the substrate W placed on the mounting surface 21a of the stage 21, a suction force is generated throughout the suction grooves 62, and the excluded region E of the substrate W is suctioned and held on the mounting surface 21a. Then, when the intake valve 67 is closed and the compressed air valve 68 is opened from this state, air is supplied between the mounting surface 21a and the substrate W, releasing the suction force of the suction groove 62 and releasing the substrate W that was held from the mounting surface 21a. That is, the exclusion area holding section 60 fixes and holds the coating area C of the placed substrate W, and the suction force is released by supplying air, thereby releasing the adsorbed state of the exclusion area E.

[0037] Similarly to the application area holding unit 50, the exclusion area holding unit 60 is configured such that the suction unit 61 can generate a suction force for each of the areas 1 to 3. That is, the suction holes 63 are arranged for each of the areas 1 to 3, and in the example of FIG. 2, four suction holes 63 are arranged in each of the areas 1 and 3, and two are arranged in the area 2. The piping 66 is provided with valves 69a, 69b, and 69c, and the suction force can be generated and released for each of the areas 1 to 3 by switching the valves 69a to 69c. That is, the valve 69a can switch the communication state with the suction hole 63 of the area 1, the valve 69b can switch the communication state with the suction hole 63 of the area 2, and the valve 69c can switch the communication state with the suction hole 63 of the area 3. Therefore, for example, when the vacuum pump 64 is operated with the valve 69a open and the valves 69b and 69c closed, the suction force can be generated only in the suction unit 61 of the area 1. Then, by opening the valves 69b and 69c in that order, the areas 2 and 3 of the substrate W are successively sucked by the suction unit 61, and the exclusion area E of the substrate W can be sucked and held on the placement surface 21a. When the compressor 65 is operated with the valves 69a to 69c open, the suction force of the suction unit 61 is released.

[0038] In addition, the exclusion area holding portion 60 is provided with a suction pad 74. This suction pad 74 is for suction-holding the substrate W separately from the suction grooves 62 and suction holes 63 that are the suction portion 61, and is provided outside the suction portion 61. That is, the suction pad 74 can stably suction-hold even a substrate W that has been deformed due to warping.

[0039] As shown in FIG. 3, an opening 75 is formed on the outside of the suction section 61, and the suction pad 74 is embedded in the opening 75. That is, the suction pad 74 is formed in an elastically deformable bellows shape, and is provided in a state where its tip protrudes from the opening 75. Specifically, the amount of protrusion is adjusted so that the tip can abut on the floating substrate W even if the substrate W is warped and floats in a state where the substrate W is placed on the mounting surface 21a of the stage 21. The suction pad 74 is connected to an intake / exhaust unit such as a vacuum pump 64 and a compressor 65 through a pipe 70. When an intake valve 71 provided on the pipe 70 is opened, a suction force is generated in the suction pad 74, and a suction force is generated. When a compressed air valve 72 provided on the pipe 70 is opened, air is supplied to the suction pad 74, and the suction force of the suction pad 74 is released (suction destruction). That is, when the vacuum pump 64 is operated in a state in which it is in contact with the substrate W floating from the mounting surface 21a due to warping, the suction pad 74 contracts and accommodates the substrate W while maintaining the attracted state, and the substrate W floating due to warping is held in a state placed on the mounting surface 21a. In this way, the suction pad 74 can be displaced from a standby position in which it protrudes from the mounting surface 21a of the stage 21 to an attracted position in which it is accommodated in the opening 75 by operating the vacuum pump 64 while attracting and holding the substrate W.

[0040] The suction pad 74 is adapted to generate a suction force for each of the areas 1 to 3. That is, the piping 70 is provided with valves 73a, 73b, and 73c, and by switching these valves, the suction pad 74 can generate and release a suction force for each of the areas 1 to 3 independently. That is, when the vacuum pump 64 is operated with the valve 73a open and the valves 73b and 73c closed, a suction force can be generated only in the suction pad 74 for the area 1, and the area 1 region of the substrate W can be sucked and held on the mounting surface 21a. Then, by opening the valves 73b and 73c in turn, the areas 2 and 3 of the substrate W are sucked by the suction pad 74 in turn, and the excluded region E of the substrate W can be sucked and held on the mounting surface 21a.

[0041] The pipes 56, 66, and 70 are provided with suction sensors (not shown) for measuring the flow rates in the pipes 56, 66, and 70. Specifically, suction sensors are provided in the pipes 56 between the valves 59a, 59b, and 59c and the stage 21, the pipes 66 between the valves 69a, 69b, and 69c and the stage 21, and the pipes 70 between the valves 73a, 73b, and 73c and the stage 21. That is, when the substrate W is sucked and held on the mounting surface 21a, the flow rates in the pipes 56, 66, and 70 change, and by measuring this change, it is possible to determine whether the substrate W has been sucked for each of the areas 1 to 3.

[0042] Next, a description will be given of the operation of the coating apparatus 1. Here, Fig. 4 is a flowchart showing the substrate holding operation, Fig. 5 is a flowchart showing the coating processing operation, and Figs. 6 and 7 are schematic views showing the state of the loaded substrate W.

[0043] First, in step S1, the substrate W is loaded. Specifically, when the substrate W held by a robot hand or the like is transported above the stage 21, the lift pins 25 protrude from the pin holes 41, and the robot hand or the like is lowered in this state to transfer the substrate W. That is, the substrate W is placed on the tip portions of the lift pins 25 (FIG. 6(a)). Then, the robot hand or the like is withdrawn, and the lift pins 25 are lowered to place the substrate W on the mounting surface 21a of the stage 21, completing the loading of the substrate W.

[0044] Next, a substrate holding step is performed in which the substrate W is attracted and held on the stage 21. In this embodiment, the substrate W is held stepwise for each of areas 1 to 3, and is attracted and held in order starting from area 1 on the coating start side.

[0045] That is, the area 1 adsorption step is performed by step S2. This area 1 adsorption step is a step of adsorbing and holding the area 1 set on the substrate W to the stage 21. Specifically, a coating area holding step of generating a suction force in the coating area holding part 50 and an exclusion area holding step of generating a suction force in the exclusion area holding part 60 are performed, and a suction force is generated in the coating area holding part 50 and the exclusion area holding part 60 belonging to the area 1 among the coating area C and the exclusion area E. That is, the valves 73a, 69a, and 59a are opened and the valves 73b, 73c, 69b, 69c, 59b, and 59c are closed, and the vacuum pumps 64 and 54 are operated to generate a suction force in the coating area holding part 50 and the exclusion area holding part 60 belonging to the area 1. Then, the lift pins 25 are lowered to place the substrate W on the placement surface 21a of the stage 21. Specifically, as shown in FIG. 6(b), the lift pins 25 descend from the coating start side in order, and the coating start side of the substrate W is sucked and held. That is, when the coating start side end of the substrate W descends due to the descent of the lift pins 25, the coating start side end of the substrate W is sucked by contacting with the suction pad 74 in the standby position. Then, the suction pad 74 contracts while sucking the substrate W, and is displaced to the suction position and accommodated in the opening 75, so that the coating side end of the substrate W is sucked and held on the placement surface 21a. At the same time that the substrate W is sucked by the suction pad 74, the exclusion region E of the substrate W in the area 1 is sucked and held by the suction portion 61 (suction groove 62 and suction hole 63) of the exclusion region holding portion 60. Then, when the exclusion region E of the substrate W in the area 1 is sucked, the coating region C of the substrate W in the area 1 is sucked and held by the suction portion 51 (suction groove 52 and suction hole 53) of the coating region holding portion 50 in the area 1. By mounting the substrates W in this manner in order from the coating start side, the substrates W can be attracted and held on the stage 21 while preventing air from accumulating between the substrates W and the mounting surface 21a.

[0046] Next, in step S3, it is confirmed whether or not the suction holding of the substrate W in area 1 has been completed. Specifically, the suction sensors monitor the flow rate changes in the pipes 56, 66, and 70, and if the suction holding has not been completed, the process proceeds in the direction of NO in step S3, and the area 1 suction step continues. Then, if the suction holding in area 1 has been completed, the process proceeds in the direction of YES in step S3, and the area 2 suction step (step S4) is started.

[0047] Also, when the area 1 adsorption step is completed, the coating process is started in parallel. That is, in step S21 of Fig. 5, the process proceeds in the direction of YES, and the coating preparation step of step S22 is performed. Specifically, the coating unit 30 enters above the substrate W, and discharges the coating liquid in the exclusion region E to form a bead film S that connects the coating unit 30 and the substrate W with the coating liquid (Fig. 6(c)). Then, in step S23, it is determined whether or not the coating region release step described below has been completed, and if the coating region release step has not been completed, the process proceeds in the direction of NO, and the coating unit 30 waits in the exclusion region E.

[0048] Next, the area 2 adsorption step is performed in step S4. This area 2 adsorption step is a step of adsorbing and holding the area of ​​area 2 set on the substrate W to the stage 21. That is, similar to the area 1 adsorption step, the coating area holding step and the exclusion area holding step are performed, and suction force is generated in the coating area holding part 50 and the exclusion area holding part 60 belonging to area 2 among the coating area C and the exclusion area E. That is, the valves 73b, 69b, and 59b are opened, and the valves 73c, 69c, and 59c are closed, and suction force is generated in the coating area holding part 50 and the exclusion area holding part 60 belonging to area 2. Note that even in the area 2 adsorption step, the adsorption and holding state for area 1 is continued, and the valves 73a, 69a, and 59a remain open. Then, the lift pins 25 are sequentially lowered, so that the exclusion area E and the coating area C in area 2 are adsorbed and held on the mounting surface 21a of the stage 21.

[0049] Next, in step S5, it is confirmed whether or not the suction and holding of the substrate W in area 2 has been completed. Specifically, this is determined based on a signal from the suction sensor, and if the suction and holding has not been completed, the process proceeds in the direction of NO in step S5, and the area 2 suction step continues. Then, if the suction and holding of area 2 has been completed, the process proceeds in the direction of YES in step S5, and the area 3 suction step (step S6) is started.

[0050] Next, the area 3 adsorption step is performed in step S6. This area 3 adsorption step is a step of adsorbing and holding the area 3 set on the substrate W to the stage 21. That is, like the area 1 and area 2 adsorption steps, the coating area holding step and the exclusion area holding step are performed, and suction force is generated in the coating area holding part 50 and the exclusion area holding part 60 belonging to the area 3 among the coating area C and the exclusion area E. That is, the valves 73c, 69c, and 59c are opened to generate suction force in the coating area holding part 50 and the exclusion area holding part 60 belonging to the area 3. Note that even in the area 3 adsorption step, the adsorption and holding state is continued for the areas 1 and 2, and the valves 73a, 69a, 59a, 73b, 69b, and 59b remain open. Then, the lift pins 25 are sequentially lowered to adsorb and hold the exclusion area E and the coating area C in the area 3 to the mounting surface 21a of the stage 21.

[0051] Next, in step S7, it is confirmed whether or not the suction and holding of the substrate W in area 3 has been completed. If the suction and holding has not been completed, the process proceeds in the direction of NO in step S7, and the suction step in area 3 continues. In this manner, the entire substrate W is suction-held on the stage 21.

[0052] 7(a), if a foreign object P is present between the substrate W and the mounting surface 21a of the stage 21, the flatness cannot be maintained by adsorbing the entire surface of the substrate W, and the portion of the substrate W where the foreign object P is present is deformed into a sharp convex shape. If the coating film M is formed in this state, coating unevenness occurs in the portion where the foreign object P is present.

[0053] Therefore, when the suction and holding of the area 3 is completed, the process proceeds in the direction of YES in step S7, and the coating area releasing process is performed in step S8. The coating area releasing process is a process of releasing the suction force of the coating area C. Specifically, the valve 57 is closed and the valve 58 is opened to release the suction force of the coating area holding part 50 in the areas 1 to 3. That is, the suction part 51 (suction groove 52 and suction hole 53) of the coating area holding part 50 is communicated with the compressor 55 to release the suction force of the coating area holding part 50, and the substrate W is held by suction only by the exclusion area holding part 60. As a result, as shown in FIG. 7(b), the exclusion area E of the substrate W remains suction-held on the mounting surface 21a of the stage 21, while the coating area C is released from the stage 21, and the part of the substrate W where the foreign matter P exists changes from a steep convex shape to a gradual shape. That is, although the entire substrate W does not become completely flat, it is possible to eliminate the locally changed parts.

[0054] When the coating area release step is completed, it is used as a trigger to proceed with the coating process. That is, in step S23, it is determined that the answer is YES, and the coating step is performed in step S24. That is, the coating unit 30 on which the bead film S is formed in the excluded area E runs while discharging the coating liquid, thereby forming a coating film M of uniform thickness in the coating area C (see FIG. 7(c)).

[0055] Then, when the coating film M is formed on the substrate W, a process of unloading the substrate W is performed in step S25. That is, after the exclusion area holding part 60 is released, the lift pins 25 are raised, and the substrate W is held by the tips of the lift pins 25. Then, the substrate W is delivered by a robot hand or the like (not shown), and the substrate W is unloaded.

[0056] Thus, according to the coating apparatus of the present embodiment, since the substrate W can be held in a state where the coating region holding part 50 is released, it is possible to suppress the formation of coating unevenness even when the foreign matter P exists between the stage 21 and the substrate W. That is, when the entire substrate W is sucked and held by the coating region holding part 50 and the exclusion region holding part 60, if the foreign matter P exists on the stage 21, the part where the foreign matter P exists adheres to the foreign matter P and deforms sharply to follow the foreign matter P. However, when the coating region holding part 50 is released while the suction of the exclusion region holding part 60 is maintained and the adsorption state to the coating region C of the substrate is released, the adhesion to the foreign matter P is released, the sharp deformation of the substrate W is alleviated, and the part where the foreign matter P exists becomes a shape close to flat. By forming the coating film M in this state, even when the foreign matter P exists, the deformation of the substrate W in that part is gentle, so that coating unevenness is not noticeable, and a uniform coating film M can be formed as a whole.

[0057] In the above embodiment, an example has been described in which the coating unit 30 waits in the exclusion area E until the coating area release step is completed in the coating process, but the coating unit 30 may be moved while discharging the coating liquid within the exclusion area E to form the coating film M. With this configuration, the coating film M is formed in the coating area C as soon as the adsorption of the coating area C is released, so that the tact time for forming the coating film M on the substrate W can be improved.

[0058] In the above embodiment, an example has been described in which the coating process is performed in parallel after the area 1 adsorption process is completed, but the coating process may be started after the coating region release process is completed. With this configuration, the coating process is performed independently after the substrate W is reliably adsorbed (exclusion region E), so that the coating film M can be formed stably without being affected by disturbances.

[0059] In the above embodiment, the substrate W is attracted by the suction grooves 52, 62 and the suction holes 53, 63. However, the substrate W may be attracted and held by only the suction holes or by other attracting means.

[0060] In addition, in the above embodiment, an example was described in which the exclusion area holding portion 60 has a suction pad 74, but if the warping of the substrate W is small, the exclusion area holding portion 60 may be composed of only suction holes 62 and 63 without using the suction pad 74.

[0061] In the above embodiment, the coating area holding unit 50 and the exclusion area holding unit 60 are divided into areas 1 to 3, and are successively attracted from the coating start side. However, the area may be divided into two, three or more, and may be changed depending on the size of the substrate W. Dividing the area into areas is preferable in terms of preventing air from remaining between the substrate W and the mounting surface 21a, but the area may not be divided and the substrate W may be attracted and held at once.

[0062] In the above embodiment, an example has been described in which air is forcibly supplied using the compressors 55, 65 to break the adhesion of the substrate W, but the adhesion of the substrate W may be broken simply by opening to the atmosphere without using the compressors 55, 65. Breaking the adhesion of the substrate W by opening to the atmosphere is preferable in that it is possible to prevent the problem of the substrate W being displaced by air, as compared to the case of forcibly supplying air.

[0063] In addition, in the above embodiment, an example was described in which the coating unit 30 moves relative to the fixed substrate W during the coating operation, but the coating operation may also be performed by moving the stage 21 relative to the fixed coating unit 30.

[0064] In the above embodiment, the substrate W is rectangular, but a circular substrate may also be used, in which case the substrate holding means 5 is provided in a circular shape according to the shape of the substrate W to be processed. [Explanation of symbols]

[0065] 1 Coating device 21 Stage 30 Coating unit 50 Coating area holding part 51 Suction part 52 Suction groove 53 Suction hole 60 Exclusion area holding unit 61 Suction part 62 Suction groove 63 Suction hole 74 Suction Pad C Application area E Exclusion area M coating film P Foreign object

Claims

1. A stage on which a substrate is placed; a coating unit that moves in one direction relative to the substrate placed on the surface of the stage and discharges a coating liquid to form a coating film on the substrate; A coating apparatus comprising: the stage has a coating region holding section that sucks and holds a coating region where a coating film that requires product precision is formed, and an exclusion region holding section that sucks and holds an exclusion region where no product precision is required for the formed coating film, the exclusion area holding unit is provided so as to surround the coating area, and is configured to be able to hold the substrate on a stage in a state in which the coating area holding unit is released; the exclusion region holding portion and the coating region holding portion are formed with suction holes that generate a suction force and suction grooves that communicate with the suction holes and open to a surface of a stage, the suction grooves of the exclusion region holding portion and the suction grooves of the coating region holding portion are formed discontinuously, the exclusion area holding portion has a suction pad embedded in the stage separately from the suction hole and the suction groove, the suction pad being formed to be displaceable between a standby position protruding from a surface of the stage and a suction position accommodated within the stage, A coating apparatus characterized in that after the entire substrate is adsorbed and held by the coating area holding part and the exclusion area holding part, when the coating area holding part is released while maintaining suction of the exclusion area holding part, the adsorption of the coating area holding part is released by forcibly supplying air.

2. A stage on which a substrate is placed; a coating unit that moves in one direction relative to the substrate placed on the surface of the stage and discharges a coating liquid to form a coating film on the substrate; The stage includes a coating region holding section that holds by suction a coating region where a coating film that requires product precision is formed, and an exclusion region holding section that holds by suction an exclusion region where product precision is not required for the formed coating film, A coating method in a coating apparatus comprising: a coating area holding step of suctioning and holding a coating area of ​​a substrate on which a coating film requiring product precision is to be formed; an exclusion region holding step of suctioning and holding an exclusion region that does not require product precision with respect to the formed coating film; a coating area releasing step of releasing the coating area from the held state; It has the exclusion region holding portion and the coating region holding portion are formed with suction holes that generate a suction force and suction grooves that communicate with the suction holes and open to a surface of a stage, the suction grooves of the exclusion region holding portion and the suction grooves of the coating region holding portion are formed discontinuously, the exclusion area holding portion has a suction pad embedded in the stage separately from the suction hole and the suction groove, the suction pad being formed to be displaceable between a standby position protruding from a surface of the stage and a suction position accommodated within the stage, the coating region holding step and the exclusion region holding step are performed to hold the substrate on the surface of the stage, and then the coating region releasing step is performed to form a coating film on the substrate in a state in which the holding state of the coating region is released; A coating method characterized in that after the entire substrate is adsorbed and held by the coating area holding process and the exclusion area holding process, when the coating area holding is released while maintaining suction on the exclusion area holding part, the adsorption of the coating area holding part is released by forcibly supplying air.

3. By the coating region holding step and the exclusion region holding step, The coating method according to claim 2, wherein when at least a predetermined area of ​​a substrate on a surface of a stage on the side where the coating unit enters is adsorbed and held, the coating unit enters onto the substrate and a coating film is formed.

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