JP2013192980A - Coating apparatus and coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating apparatus and a coating method capable of appropriately maintaining the film thickness of a coating liquid at a corner part of a substrate, regardless of a simple configuration.SOLUTION: On a stage 11, an opening 40 is formed, and a sucker 41 is disposed inside the opening 40. The sucker 41 is connected with an elevating/lowering part 44 including a screw mechanism in the inside through an elevating/lowering shaft 43. Also, the elevating/lowering par 44 is connected with a motor 45. The sucker 41 is elevated and lowered by the drive of the motor 45. Then, the elevating/lowering amount, that is a height position, is controlled by a rotation amount of the motor 45.

Description

  The present invention relates to a coating apparatus and a coating method for coating a coating liquid on a surface of a substrate.

  For example, a coating solution is applied to the surface of a rectangular substrate such as a glass substrate for an organic EL display device, a glass substrate for a liquid crystal display device, a panel substrate for a solar cell, a glass substrate for a PDP, a glass substrate for a photomask, or a substrate for an optical disk. In this case, a slit nozzle that applies a coating solution to the surface of the substrate by moving in the horizontal direction in a state of being close to the surface of the substrate is used. When applying a coating liquid to such a rectangular substrate using a slit nozzle, there is a problem that the film thickness of the coating liquid applied to the corners that are the four corner areas cannot be made uniform. .

  For this reason, conventionally, a countermeasure has been taken to optimize the shape of the slit nozzle. Further, in Patent Document 1, a side plate is attached to the end face of the nozzle body in the slit nozzle, and by using this side plate, a decrease in film thickness near both ends of the thin film formed on the substrate is prevented. A substrate processing apparatus having a slit nozzle is disclosed.

JP 2008-68224 A

  The substrate processing apparatus described in Patent Document 1 considers the film thickness at both ends of the thin film, and does not pay attention to the film thickness at the corners of the substrate. In addition, even if it is attempted to control the film thickness of the coating liquid applied to the corners of the substrate by optimizing the configuration of the slit nozzle, if the conditions such as the viscosity of the coating liquid are greatly different, the slit nozzle itself is changed. Since it is necessary to change, the cost for manufacturing the nozzle is high.

  The present invention has been made to solve the above-described problems, and provides a coating apparatus and a coating method capable of appropriately maintaining the film thickness of the coating solution at the corners of the substrate while having a simple configuration. For the purpose.

  The invention described in claim 1 is a coating apparatus that applies a coating liquid to a surface of a rectangular substrate, and a stage on which the substrate is placed, and a state in which the substrate is placed close to the surface of the substrate placed on the stage. A slit nozzle that applies a coating liquid to the surface of the substrate by moving in a horizontal direction relative to the substrate, a corner lifting mechanism that lifts and lowers a corner of the substrate placed on the stage, and the corner And a controller for controlling the amount of elevation of the corners of the substrate by the part elevation mechanism.

  The invention according to claim 2 is the invention according to claim 1, wherein the stage has an opening at a position corresponding to the corner of the substrate placed on the stage, and the corner lifting mechanism is A suction plate that sucks and holds the lower surface of the corner portion of the substrate placed in the opening and placed on the stage; and a lifting unit that is placed in the opening and lifts and lowers the suction plate.

  According to a third aspect of the present invention, in the second aspect of the present invention, a suction groove for sucking and holding the substrate is formed on the surface of the stage, and the opening is formed by the suction groove. Formed in the outer region.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the correlation data indicates the relationship between the type of the coating liquid applied to the substrate and the height position of the corner portion. The control unit controls the amount of elevation of the corners of the substrate by the corner elevation mechanism based on the correlation data stored in the storage unit.

  A fifth aspect of the present invention includes the sensor according to the fourth aspect of the present invention, wherein the sensor measures a height position of a corner portion of the substrate with respect to the stage.

  According to a sixth aspect of the present invention, there is provided a coating method for coating a surface of a rectangular substrate with a coating solution, a loading step for loading the substrate onto a stage, and a suction holding step for sucking and holding the substrate on the stage. A corner raising / lowering step of raising and lowering a corner portion of the substrate sucked and held on the stage by sucking and holding the substrate from its lower surface; The coating step of applying a coating solution to the surface of the substrate by moving the substrate relative to the horizontal direction, and the unloading step of stopping the adsorption holding of the substrate and unloading the substrate from the stage. It is characterized by having.

  According to the first and sixth aspects of the present invention, by raising and lowering the corners of the substrate, the film thickness of the coating solution at the corners of the substrate is appropriately adjusted even when the properties of the coating solution are greatly different. Can be maintained.

  According to invention of Claim 2, it becomes possible to raise / lower suitably the corner | angular part of a board | substrate with the suction disk arrange | positioned in the opening part formed in the stage.

  According to the third aspect of the present invention, the corner of the substrate sucked and held on the stage by the action of the suction groove can be lifted and lowered by the suction disk disposed in the opening formed on the outside thereof. Become.

  According to the fourth aspect of the present invention, it is possible to set the amount of elevation of the corners of the substrate to an appropriate value according to the type of the coating liquid.

  According to the fifth aspect of the present invention, it is possible to check the amount of elevation of the corner portion of the substrate by the corner elevation mechanism by the sensor and set the amount of elevation to an appropriate value.

It is a perspective view of the coating device concerning this invention. It is a side surface schematic diagram of the coating device concerning this invention. 3 is a plan view showing the positional relationship between an opening 40, a suction disk 41, a suction groove 42, and a substrate 100 placed on a stage 11. FIG. FIG. 3 is a front schematic diagram showing a positional relationship between a substrate 100 held by suction on a stage 11, a slit nozzle 13 and a suction board 41. It is a schematic diagram which expands and shows the principal part of FIG. It is a plane schematic diagram which shows the sensor 12 for measuring the height position of the corner | angular part of the board | substrate 100 with the board | substrate 100 grade | etc.,. It is a block diagram which shows the main control systems concerning this invention. It is explanatory drawing which shows the application state of the coating liquid 101. FIG. It is explanatory drawing which shows the application state of the coating liquid 101. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a coating apparatus according to the present invention. FIG. 2 is a schematic side view of the coating apparatus according to the present invention. In FIG. 1, a nozzle cleaning mechanism 31 and a pre-dispensing mechanism 34, which will be described later, are not shown. In FIG. 2, the carriage 14 and the like which will be described later are not shown.

  This coating apparatus includes a stage 11 for holding the substrate 100 by suction. As this stage 11, a stone surface plate or the like whose flatness of the upper surface is about several micrometers is used. An adsorption groove 42 is formed on the surface of the stage 11. Further, near the surface of the stage 11, a suction disk 41 that holds the lower surface of the corner portion of the substrate 100 is provided. The suction plate 41 is disposed in an opening 40 described later. As will be described later, the substrate 100 sucked and held on the stage 11 by the action of the suction groove 42 is lifted and lowered with its corners sucked and held by these suction disks 41. The stage 11 is provided with a plurality of lift pins (not shown) at appropriate intervals. The lift pins support the substrate 100 from below and lift it upward from the surface of the stage 11 when the substrate 100 is loaded and unloaded. The opening 40 may be a recess formed in the stage 11 or a hole that penetrates the stage 11. The opening 40 referred to in this specification is a concept including various shapes in which a space capable of storing the suction disk 41 and the like is formed from the surface of the stage 11 toward the inside.

  The suction board 41 is connected to exhaust means such as a vacuum pump and an exhaust fan via an on-off valve 18 described later. Further, the suction groove 42 is connected to exhaust means such as a vacuum pump or an exhaust fan via an on-off valve 19 described later.

  Above the stage 11, a carriage 14 is provided that extends substantially horizontally from both sides of the stage 11. The carriage 14 includes a nozzle support portion 15 for supporting the slit nozzle 13 and a pair of left and right lifting mechanisms 16 for supporting both ends of the nozzle support portion 15. In addition, a pair of running rails 17 extending in parallel to the substantially horizontal direction are disposed at both ends of the stage 11. These running rails 17 reciprocate the carriage 14 in the X direction shown in FIG. 1 by guiding both ends of the carriage 14.

  A pair of linear motors 20 each provided with a stator 21 and a moving element 22 are disposed along both side edges of the stage 11 at both side portions of the stage 11 and the carriage 14. A pair of linear encoders 23 each having a scale portion and a detector are fixed to both sides of the stage 11 and the carriage 14. The linear encoder 23 detects the position of the carriage 14.

  Further, as shown in FIG. 2, a nozzle cleaning mechanism 31 is disposed on the side of the stage 11. The nozzle cleaning mechanism 31 includes a cleaning block 32 and a standby pod 33. In this coating apparatus, the slit nozzle 13 is cleaned by the nozzle cleaning mechanism 31 before or after the coating operation is performed.

  Further, as shown in FIG. 2, a pre-dispensing mechanism 34 is disposed on the side of the stage 11. The pre-dispensing mechanism 34 includes a pre-dispensing roller 36 in which a part thereof is immersed in the cleaning liquid stored in the storage tank 35 and a doctor blade 37. The pre-dispensing roller 36 and the doctor blade 37 have a length equal to or longer than that of the slit nozzle 13 in the Y direction. The pre-dispensing roller 36 is rotated by driving a motor (not shown). In this coating apparatus, before performing the coating operation, a small amount of coating liquid is discharged from the slit nozzle 13 moved above the pre-dispensing roller 36, so that the coating liquid containing the cleaning liquid at the time of cleaning by the nozzle cleaning mechanism 31. Is removed from the slit nozzle 13.

  FIG. 3 is a plan view showing the positional relationship between the opening 40, the suction disk 41 and the suction groove 42 described above, and the substrate 100 placed on the stage 11. As shown in FIG.

  As shown in FIG. 3, a suction groove 42 for sucking and holding the substrate 100 is formed in a region corresponding to the lower surface of the substrate 100 on the surface of the stage 11. Then, as shown in an enlarged view in FIG. 3, there are openings at positions outside the suction grooves 42 corresponding to the four corners of the substrate 100 sucked and held on the surface of the stage 11 by the action of the suction grooves 42. 40 is formed, and a suction disk 41 for holding the lower surface of the corner portion of the substrate 100 by suction is disposed in the opening 40.

  4 is a schematic front view showing the positional relationship between the substrate 100 sucked and held on the stage 11, the slit nozzle 13 and the suction disk 41, and FIG. 5 is an enlarged schematic view showing the main part of FIG. 4. It is.

  In the stage 11, the above-described opening 40 is formed, and the suction plate 41 is disposed in the opening 40. The suction plate 41 is connected to an elevating unit 44 having a screw mechanism therein via an elevating shaft 43. The elevating unit 44 is connected to a motor 45. The suction disk 41 is moved up and down by driving the motor 45. The elevation amount, that is, the height position is controlled by the rotation amount of the motor 45.

  FIG. 6 is a schematic plan view showing the sensor 12 for measuring the height position of the corner of the substrate 100 together with the substrate 100 and the like.

  A pair of sensors 12 for measuring the height positions of the corners of the substrate 100 are disposed on the lower surface of the nozzle support portion 15 described above. These sensors 12 are arranged at positions corresponding to the vicinity of the edge of the substrate 100 that is sucked and held on the stage 11. For this reason, when the nozzle support part 15 reciprocates in the X direction shown in FIG. 1 together with the slit nozzle 13, the pair of sensors 12 move to positions that face the pair of edges of the substrate 100. When the sensor 12 faces the four corners of the substrate 100 during the movement, the height of the corners is measured. In addition, as such a sensor 12, various sensors, such as an optical sensor, are employable.

  FIG. 7 is a block diagram showing a main control system according to the present invention.

  The coating apparatus has a control unit 51 that controls the entire apparatus. The control unit 51 is connected to the storage unit 52. The control unit 51 is connected to the sensor 12 and the motor 45 described above. Further, as described above, the control unit 51 is disposed between the suction plate 41 and the exhaust unit, and is arranged between the on-off valve 18 for turning on and off the exhaust operation by the suction plate 41, and between the suction groove 42 and the exhaust unit. The on-off valve 19 is also connected to turn on and off the exhaust operation by the suction plate 42. As will be described later, the storage unit 52 stores correlation data indicating the relationship between the type of coating liquid applied to the substrate 100 and the height positions of the corners on the substrate 100.

  Next, the application | coating operation | movement of the coating liquid by the coating device mentioned above is demonstrated. 8 and 9 are explanatory views showing the application state of the application liquid 101 by the application apparatus described above.

  When a coating operation is executed by this coating apparatus, first, the substrate 100 is loaded onto the stage 11 by a transport mechanism (not shown). Then, the control unit 51 controls the opening and closing of the on-off valve 19 shown in FIG. 7 and exhausts air from the adsorption groove 42, whereby the substrate 100 is adsorbed and held on the stage 11. Further, the controller 51 controls the opening / closing valve 18 shown in FIG. 7 to open and close and exhausts the suction plate 41 to hold the lower surface of the corner portion of the substrate 100 by suction.

  Next, based on the correlation data indicating the relationship between the type of the coating liquid applied to the substrate 100 stored in the storage unit 52 and the appropriate height position of the corner of the substrate 100 at that time, the control unit 51. By controlling the rotation of the motor 45 by the above control, the height position of the suction plate 41 is changed. Thereby, the height position of the corner portion of the substrate 100 sucked and held on the stage 11 is changed.

  That is, as shown in FIG. 8, the height position of the corners of the substrate 100 is lowered by the lowering of the suction plate 41 that sucks and holds the corners of the substrate 100, and the surface of the corners of the slit nozzle 13 and the substrate 100 is lowered. Increases the amount of bead of the coating liquid 101 formed between the slit nozzle 13 and the surface of the corner portion of the substrate 100. At this time, the film thickness of the coating liquid 101 applied to the corners of the substrate 100 is large. On the other hand, as shown in FIG. 9, the height position of the corners of the substrate 100 increases as the suction plate 41 that sucks and holds the corners of the substrate 100 rises. When the distance from the surface of the portion becomes smaller, the amount of bead of the coating liquid 101 formed between the slit nozzle 13 and the surface of the corner portion of the substrate 100 becomes smaller. At this time, the film thickness of the coating liquid 101 applied to the corners of the substrate 100 is small. The bead means a liquid pool generated between the slit nozzle 13 and the surface of the substrate 100 and is also called a meniscus.

  The film thickness of the coating liquid 101 formed at the corners of the substrate 100 varies depending on the viscosity and surface tension of the coating liquid 101. In addition, the film thickness of the coating liquid 101 formed at the corner of the substrate 100 is such that the coating liquid 101 is pulled near the center of the substrate 100 when the coating liquid 101 is dried. It also changes depending on. For this reason, correlation data that optimizes the relationship between the type of coating liquid 101 applied to the substrate 100 and the height position of the corners of the substrate 100 has been experimentally obtained in advance, and is stored in the storage unit 52. It is remembered. And at the time of application | coating of the coating liquid 101, the control part 51 controls rotation of the motor 45 based on this correlation data, and changes the height position of the suction disk 41. FIG.

  In this state, the slit nozzle 13 is moved along the surface of the substrate 100 by driving the linear motor 20 in a state where the slit nozzle 13 is brought close to the surface of the substrate 100 sucked and held on the stage 11, and the coating liquid Supply to the surface. As a result, a thin film of the coating liquid 101 is formed on the surface of the substrate 100.

  Further, when the slit nozzle 13 is moved, when the nozzle support portion 15 is reciprocated in the X direction shown in FIG. 1 together with the slit nozzle 13, the pair of sensors 12 move to positions facing the pair of edges of the substrate 100. And this sensor 12 passes through the position which opposes the corner | angular part of the four corners of the board | substrate 100 at the time of this movement, and measures the height position of these corner | angular parts. Thereby, it becomes possible to confirm the height position of the corner of the actual substrate 100. And when the height position of the board | substrate 100 differs from a setting value, the control part 51 controls rotation of the motor 45, and changes the height position of the suction disk 41 further.

  When the application of the coating liquid to the surface of the substrate 100 is completed by the above operation, the substrate 100 is unloaded from the stage 11 by a transport mechanism (not shown).

  In the above-described embodiment, the height position of the corner portion of the substrate 100 attracted and held on the stage 11 is changed based on the correlation data stored in the storage unit 52, but the present invention is not limited to this. . For example, when the type of the coating liquid is changed, an appropriate height position on the substrate 100 may be input to the control unit 51 by the operator.

DESCRIPTION OF SYMBOLS 11 Stage 12 Sensor 13 Slit nozzle 14 Carriage 15 Nozzle support part 16 Elevating mechanism 17 Traveling rail 18 On-off valve 19 On-off valve 20 Linear motor 23 Linear encoder 31 Nozzle cleaning mechanism 34 Pre-dispensing mechanism 40 Opening 41 Adsorption board 42 Adsorption groove 43 Elevation Shaft 44 Lifting unit 45 Motor 51 Control unit 52 Storage unit 100 Substrate 101 Coating liquid

Claims (6)

In a coating apparatus that applies a coating liquid to the surface of a rectangular substrate,
A stage on which the substrate is placed;
A slit nozzle that applies a coating liquid to the surface of the substrate by moving in a horizontal direction relative to the substrate in a state of being close to the surface of the substrate placed on the stage;
A corner lifting mechanism that lifts and lowers a corner of the substrate placed on the stage;
A controller that controls the amount of elevation of the corners of the substrate by the corner elevation mechanism;
A coating apparatus comprising: The coating apparatus according to claim 1,
The stage has an opening at a position corresponding to a corner of the substrate placed on the stage,
The corner raising / lowering mechanism includes a suction plate that sucks and holds the lower surface of the corner of the substrate placed in the opening and placed on the stage, and a lifting portion that is arranged in the opening and lifts the suction plate. A coating apparatus comprising: The coating apparatus according to claim 2,
A suction groove for sucking and holding the substrate is formed on the surface of the stage,
The said opening part is a coating device formed in the outer side area | region of the said adsorption groove. In the coating device in any one of Claims 1-3,
A storage unit for storing correlation data indicating the relationship between the type of coating liquid applied to the substrate and the height position of the corners;
The said control part is a coating device which controls the raising / lowering amount of the corner | angular part of the said board | substrate by the said corner | angular part raising / lowering mechanism based on the correlation data memorize | stored in the said memory | storage part. The coating apparatus according to claim 4, wherein
A coating apparatus comprising a sensor for measuring a height position of a corner portion of the substrate with respect to the stage. In the coating method of coating the coating liquid on the surface of the rectangular substrate,
A loading step of loading the substrate onto a stage;
A suction holding step for sucking and holding the substrate on a stage;
A corner lifting / lowering step of lifting and lowering the corners of the substrate sucked and held on the stage by sucking and holding from the lower surface;
An application step of applying a coating liquid to the surface of the substrate by moving the slit nozzle in a horizontal direction relative to the substrate in a state of being close to the surface of the substrate held by suction on the stage;
An unloading step of stopping suction holding of the substrate and unloading the substrate from the stage;
A coating method characterized by comprising:

Images