JP2017148769A - Coating device and coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a thickness of a coating film coated on a coating object member in a desired thickness.SOLUTION: An applicator 10 of a coating device 5 comprises a reservoir part 13 for reserving a coating liquid, a discharge port 11 for discharging the coating liquid and a slit-like flow passage 12 for connecting the reservoir part 13 and the discharge port 11, and discharges the coating liquid from the discharge port 11 to a substrate 7. The coating device 5 comprises movement means 20 for moving the applicator 10 in the parallel direction to a coating object surface 8 to the substrate 7, a pump 30 for supplying the coating liquid to the applicator 10 and a control device 50. The control device 50 executes control for supplying the coating liquid to the applicator 10 from the pump 30 while putting the coating liquid in the applicator 10 under negative pressure in coating operation of discharging the coating liquid from the discharge port 11 to the substrate 7 while moving the applicator 10.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a coating apparatus and a coating method for forming a coating film on a member to be coated.

As a coating device for forming a coating film with a uniform thickness on a member to be coated (for example, a circular substrate such as a silicon wafer), a slit coater and a spin coater are widely known, but each has different characteristics. Applications have been developed according to the characteristics.
The slit coater is used, for example, for forming a coating film on a color filter of a liquid crystal display or a TFT substrate. The slit coater is applicable to a large glass substrate, and utilizes the characteristics that the use efficiency of the coating liquid is high (that is, the waste of the coating liquid is small).
A spin coater is relatively inferior to a slit coater in terms of compatibility with large substrates and application efficiency of coating solution, but it is relatively easy to form a coating with a uniform thickness on a circular substrate such as a silicon wafer. It is widely used in the field of semiconductor manufacturing.

However, in recent years, slit coaters are also being used in the semiconductor manufacturing field in order to increase the utilization efficiency of coating liquids (see, for example, Patent Document 1 and Patent Document 2). The slit coater has an applicator (also referred to as a nozzle or a slit die), in which a slit-like channel is formed, and its tip serves as a discharge port for the coating liquid. The discharge port has an elongated shape, and has a width dimension larger than the diameter of the circular substrate (silicon wafer).
Then, the substrate and the applicator (discharge port) are moved relative to each other, and the discharge port is formed by the surface tension of the coating liquid (coating liquid bead) generated between the substrate and the applicator. It is possible to discharge (draw out) the coating liquid. For this reason, the coating liquid is discharged (drawn) in a portion where the substrate is present facing the elongated discharge port, whereas the coating liquid is not discharged (not drawn) in a portion where there is no substrate. As a result, it becomes possible to form a coating film on a necessary portion without wasting the coating liquid on a circular substrate such as a silicon wafer or the like, and the utilization efficiency of the coating liquid can be improved. .

In addition, such a slit coater (also referred to as a capillary coater) has conventionally been configured with the discharge port of the applicator facing upward, but as disclosed in Patent Document 1 and Patent Document 2, the discharge port There are proposals that face down. In this slit coater, the discharge port of the applicator is turned downward, and control is performed to maintain the pressure (internal pressure) of the coating liquid in the applicator at a negative pressure. Then, the coating liquid is pulled out from the coating device by the surface tension of the coating solution (coating solution bead) generated between the substrate and the coating device, and the coating solution is efficiently applied to a circular substrate such as a silicon wafer. ing.
The advantage that the discharge port faces downward is that the coating surface of the substrate can be directed upward, which makes it easier to handle the substrate and suppresses the liquid flow after coating.

JP 2013-98371 A JP-A-2015-192984

  When applying a coating solution to a substrate using a capillary coater with the discharge port of the applicator facing downward, the main control parameters that affect the film thickness of the coating solution are the pressure in the applicator and the coating speed. Even when coating is performed using these control parameters, high-precision control is required to stably reproduce the film thickness.

  The capillary coater described in Patent Document 1 has a narrow storage chamber for storing a coating liquid inside an applicator, and is configured to control the pressure (atmospheric pressure) of the storage chamber. When the application liquid in the storage chamber is discharged from the discharge port, that is, when the application liquid is consumed for application, the liquid level of the application liquid in the storage chamber decreases. Although the coating liquid is newly supplied to the applicator (storage chamber) from the outside, since the storage chamber is narrow, the fluctuation of the liquid level accompanying the consumption (and supply) of the coating liquid is large. Control of keeping the pressure in the storage chamber constant is substantially difficult.

  The capillary coater described in Patent Document 2 includes a tank for storing a coating liquid connected to the applicator via a pipe, and the pressure provided in the applicator so that the pressure in the applicator is constant. The tank pressure is feedback controlled based on the measured value of the sensor. However, due to the pressure loss that occurs when the coating liquid flows through the flow path (pipe) from the tank to the applicator, the movement of the coating liquid may be delayed and control responsiveness may decrease. That is, even if the tank pressure is controlled, there is a time lag until the pressure change due to the control is reflected in the pressure in the applicator. As a result, the pressure in the applicator does not become the desired pressure. Or the pressure in the applicator fluctuates.

As described above, when the control of the pressure in the applicator is unstable, the discharge amount of the coating liquid discharged from the applicator fluctuates, and as a result, the film thickness of the coating film formed on the coated member May not be uniform.
Accordingly, the present invention has been made to solve the problems of the above-described capillary coater (capillary coating), and the object of the present invention is to determine the thickness of the coating film formed on the member to be coated. An object of the present invention is to provide a coating apparatus and a coating method that can be made to have a thickness of 10 mm.

The coating apparatus of the present invention has a reservoir part for storing the coating liquid, a discharge port for discharging the coating liquid, and a slit-like channel connecting the reservoir part and the discharge port, An applicator for discharging a coating liquid from a discharge port; a moving means for relatively moving the applicator and the member to be coated in a direction parallel to a surface to be coated of the member to be coated; and supplying the coating liquid to the applicator And a coating operation for discharging the coating liquid from the discharge port to the coated member while performing the relative movement, and applying the coating liquid from the pump while applying a negative pressure to the coating liquid in the coating device. And a control device that performs control for supplying to the applicator.
According to this coating apparatus, it is possible to perform capillary coating that enables the coating liquid to be ejected from the ejection port to form a coating film having a desired thickness on the coated member (coated surface).

Further, the control device can perform control to supply a coating liquid from the pump to the applicator according to the amount of the coating liquid discharged from the discharge port during the coating operation.
According to this configuration, during the coating operation, the coating liquid corresponding to the amount of coating liquid consumed by being discharged from the discharge port is supplied from the pump to the applicator. Control of capillary coating formed on the member to be coated (surface to be coated) becomes easy.

The applicator further includes a pressure applying device that applies pressure to the coating liquid in the applicator, and a pressure sensor that measures the pressure of the coating liquid in the applicator. In order to make the application liquid in the applicator negative, the pressure applying device controls the pressure of the application liquid in the applicator, and controls the adjustment of the application liquid by the pump based on the measurement result of the pressure sensor. It can be carried out.
According to this configuration, pressure control for keeping the pressure (negative pressure) in the applicator constant is performed, and a capillary coating for forming a coating film with a desired thickness on the coated member (coated surface) is performed. Control becomes easy.

Moreover, when making a coating liquid adhere to the application | coating start part of a to-be-coated member, it is preferable to control the discharge amount of a coating liquid appropriately and to obtain a desired film thickness from a coating start part. Therefore, the control device supplies the application liquid to the applicator by the pump for the liquid application operation to start the application of the application liquid to the member to be applied, and the supply of the application liquid in the applicator by the supply. After the pressure is increased, when the pressure drop is detected, it is preferable to stop the supply of the coating liquid by the pump.
When the application liquid is supplied from the pump to the applicator, the pressure of the application liquid in the applicator increases once, and thereby the application liquid is discharged from the discharge port. When the coating liquid comes into contact with the member to be coated, the coating liquid in the applicator is further drawn out by the surface tension of the coating liquid, thereby reducing the pressure in the applicator. Therefore, when the pressure drop is detected, the supply of the coating liquid by the pump is stopped, so that it is possible to prevent the excessive coating liquid from adhering to the member to be coated during the liquid application operation.

Further, for the liquid application operation, the coating device is connected to the applicator through a pipe and stores a coating liquid, and the pressure of the coating liquid in the applicator is maintained at a predetermined value. A pressure regulator for adjusting the pressure of the coating liquid stored in the tank; and a valve that allows the applicator and the tank to communicate with and shut off, and the control device uses the valve to apply the coating. The supply of the coating liquid by the pump is stopped when a drop in the pressure is detected after the coating liquid is supplied to the applicator by the pump while the communication between the container and the tank is cut off. At the same time, it is preferable that the tank and the applicator communicate with each other by operating the valve.
According to this configuration, the pressure of the application liquid in the applicator can be maintained at a constant value (negative pressure) after the application liquid discharged from the discharge port adheres to the application target member during the liquid application operation. It becomes.

Further, the coating method of the present invention includes a reservoir part for storing the coating liquid, a discharge port for discharging the coating liquid, and a discharge port of the applicator having a slit-like channel connecting the reservoir part and the discharge port. A method for performing capillary coating by discharging a coating liquid onto a member to be coated, wherein the applicator and the member to be coated are relatively moved in a direction parallel to a surface to be coated of the member to be coated. However, a coating operation is performed to discharge the coating liquid from the discharge port to the coated member, and the coating liquid is supplied from a pump connected to the coating device while applying a negative pressure to the coating liquid in the coating device during the coating operation. Is supplied to the applicator.
According to this coating method, it is possible to perform capillary coating that enables the coating liquid to be ejected from the ejection port to form a coating film having a desired thickness on the coated member (coated surface).

Further, during the coating operation, a coating liquid corresponding to the amount of the coating liquid discharged from the discharge port is supplied from the pump to the applicator.
According to this configuration, during the coating operation, the coating liquid corresponding to the amount of coating liquid consumed by being discharged from the discharge port is supplied from the pump to the applicator. Control of capillary coating formed on the member to be coated (surface to be coated) becomes easy.

The pressure of the coating liquid in the applicator is measured by a pressure sensor, and the pressure of the coating liquid in the applicator is controlled to make the coating liquid in the applicator negative, and the pressure sensor Based on the measurement result, adjustment control of the coating liquid by the pump is performed.
According to this configuration, pressure control for keeping the pressure (negative pressure) in the applicator constant is performed, and a capillary coating for forming a coating film with a desired thickness on the coated member (coated surface) is performed. Control becomes easy.

Moreover, when making a coating liquid adhere to the application | coating start part of a to-be-coated member, it is preferable to control the discharge amount of a coating liquid appropriately and to obtain a desired film thickness from a coating start part. Therefore, after the application liquid is supplied to the applicator by the pump and the pressure of the application liquid in the applicator is increased by the supply for the liquid application operation for starting the adhesion of the application liquid to the coated member. When the pressure drop is detected, the supply of the coating liquid by the pump is preferably stopped.
When the application liquid is supplied from the pump to the applicator, the pressure of the application liquid in the applicator increases once, and thereby the application liquid is discharged from the discharge port. When the coating liquid comes into contact with the member to be coated, the coating liquid in the applicator is further drawn out by the surface tension of the coating liquid, thereby reducing the pressure in the applicator. Therefore, when the pressure drop is detected, the supply of the coating liquid by the pump is stopped, so that it is possible to prevent the excessive coating liquid from adhering to the member to be coated during the liquid application operation.

For the liquid application operation, the applicator is connected to a tank for storing the application liquid through a pipe, and is provided with a valve that allows the applicator and the tank to communicate with each other. The pressure of the coating liquid stored in the tank can be adjusted by a pressure regulator so as to keep the pressure of the coating liquid in the applicator at a predetermined value, and the applicator and the tank are controlled by the valve. When the pressure drop is detected after the coating liquid is supplied to the applicator by the pump in a state where communication with the pump is cut off, the supply of the coating liquid by the pump is stopped and the valve is operated. It is preferable that the tank and the applicator communicate with each other.
According to this configuration, the pressure of the application liquid in the applicator can be maintained at a constant value (negative pressure) after the application liquid discharged from the discharge port adheres to the application target member during the liquid application operation. It becomes.

  According to the present invention, the amount of the application liquid supplied to the applicator is controlled to a predetermined amount by a pump, so that the surface tension of the application liquid discharged from the applicator to the member to be applied is moved from the discharge port to the outside of the applicator. The amount of the coating liquid that is about to be discharged can be suppressed. As a result, during the coating operation, the coating liquid in the coating device is maintained at a negative pressure, and the thickness of the coating film applied to the member to be coated can be set to a desired thickness.

It is a schematic block diagram explaining the whole structure of a coating device. It is explanatory drawing of an applicator and a board | substrate. It is explanatory drawing explaining the coating method. It is explanatory drawing explaining the coating method. It is explanatory drawing explaining the coating method. It is explanatory drawing explaining the coating method.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[About the configuration of the coating device]
FIG. 1 is a schematic configuration diagram illustrating the overall configuration of the coating apparatus. The coating apparatus 5 is an apparatus for forming a coating film having a uniform thickness by discharging a coating liquid onto a member to be coated that is, for example, a sheet. Note that the member to be applied described in the present embodiment is a circular substrate 7 (see FIG. 2A), specifically, a circular silicon wafer.

The coating device 5 includes an applicator 10 (also referred to as a nozzle or a slit die) positioned above the substrate 7, and the coating liquid is discharged from the applicator 10 to apply the coating liquid onto the upper surface of the substrate 7. . The upper surface of the substrate 7 becomes a coated surface 8 to which the coating liquid is applied, and the substrate 7 is supported on the stage 9 in such a posture that the coated surface 8 faces upward, and coating is performed in this state.
In addition to the applicator 10 that discharges the coating liquid, the coating apparatus 5 includes a moving unit 20 that relatively moves the substrate 7 and the coating apparatus 10, and a pump 30 that supplies the coating liquid to the coating apparatus 10. A pressure applying device 40 that applies pressure to the coating liquid in the applicator 10, a control device 50 that includes a computer that performs various controls, and a pressure sensor 60 for measuring the pressure of the coating liquid in the applicator 10. I have.

  The applicator 10 will be described. As shown in FIG. 2 (A), the applicator 10 is composed of a linear nozzle that is long in one direction, and a discharge port 11 that is long in one direction for discharging the coating liquid is provided at the lower end thereof. As described above, the substrate 7 (surface 8) is circular, and the discharge port 11 has a width dimension W larger than the diameter D of the substrate 7 (the maximum dimension of the substrate 7 in the one direction) (W> D). For this reason, in the applicator 10 (discharge port 11), a portion where the substrate 7 exists immediately below and a portion where the substrate 7 does not exist immediately below are generated, and the range (length) of each of these portions is: It changes according to the relative position of the substrate 7 and the applicator 10 (discharge port 11). 2A is a perspective view showing the applicator 10 and the substrate 7, and FIG. 2B is a cross-sectional view of a portion of the applicator 10 where the substrate 7 exists immediately below. (C) is sectional drawing in the part in which the board | substrate 7 does not exist directly under the applicator 10. FIG.

  As shown in FIGS. 2B and 2C, the applicator 10 has a reservoir portion 13 for storing the coating liquid, a discharge port 11 for discharging the coating liquid, and a slit shape connecting the reservoir portion 13 and the discharge port 11. A flow path 12 is provided. The reservoir 13, the slit-shaped flow path 12, and the discharge port 11 are formed long along one direction (a direction orthogonal to the paper surface of FIGS. 2B and 2C). The reservoir 13 is an area that has been enlarged to temporarily store the coating liquid discharged from the discharge port 11. The lower end of the slit-shaped flow path 12 is a discharge port 11. In the applicator 10, the coating liquid is discharged downward from the discharge port 11 to the substrate 7. During the application operation described later, the reservoir 13 and the slit-like flow path 12 are filled with the coating liquid (that is, filled). In the present embodiment, the direction in which the coating liquid is discharged from the discharge port 11 is downward. However, the direction is not limited to this, and may be obliquely downward, and may be horizontal (horizontal direction), upward, and diagonally upward. There is also a case.

  In FIG. 1, a pressure sensor 60 is a sensor that is provided in the applicator 10 and measures the pressure of the coating liquid in the applicator 10. In this embodiment, the detection part (sensor part) of the pressure sensor 60 is exposed in the reservoir part 13, and the pressure (internal pressure) of the coating liquid in the reservoir part 13 is measured. The measurement result of the pressure sensor 60 is input to the control device 50. In the following, “pressure in the applicator 10” means the pressure of the coating liquid in the reservoir 13.

The coating apparatus 5 includes an apparatus base 6 and a stage 9 mounted on the apparatus base 6 and placing a substrate 7 thereon. The coated surface 8 of the substrate 7 on the stage 9 is horizontal. In the present embodiment, the applicator 10 can be moved by the moving means 20 with respect to the stage 9.
The moving means 20 includes a rail 21 provided on the apparatus base 6, a movable block 22 that moves in the horizontal direction along the rail 21, and a linear actuator 23 that moves the movable block 22. The applicator 10 is mounted on the movable block 22. By this moving means 20, the applicator 10 can move in the horizontal direction with respect to the substrate 7 on the stage 9 in a fixed state. The moving unit 20 may be configured to relatively move the applicator 10 and the substrate 7 in a direction parallel to the surface to be coated 8 of the substrate 7. The stage 9 (substrate 7) may be moved. Moreover, the moving means 20 is provided with the raising / lowering actuator 24 which moves the applicator 10 to an up-down direction. Thereby, the height of the applicator 10 (discharge port 11) with respect to the substrate 7 can be adjusted. The moving means 20 is controlled by the control device 50 and can move the applicator 10 in the horizontal direction at a predetermined speed (specifically, a constant speed).

  In the coating apparatus 5, the substrate 7 and the applicator 10 (discharge port 11) are opposed to each other in the vertical direction, and are moved relative to each other by the moving means 20, and between the substrate 7 and the applicator 10. The coating liquid is discharged from the applicator 10 by the surface tension acting on the generated coating liquid (bead 3 of the coating liquid). For this reason, the coating liquid is discharged to the elongated discharge port 11 at a portion where the substrate 7 exists as shown in FIG. 2B, whereas the substrate 7 has a shape as shown in FIG. The coating solution is not discharged in the absence of the coating liquid. As a result, when the circular substrate 7 is to be applied, it is possible to form a coating film on a necessary portion without wasting the application liquid, thereby increasing the utilization efficiency of the application liquid.

  In FIG. 1, the pump 30 has a function of supplying a desired amount of coating liquid to the applicator 10. The pump 30 can accurately deliver a coating liquid having an arbitrary flow rate, and is, for example, a syringe pump (metering pump). The applicator 10 and the pump 30 are connected through a pipe 81, and the pipe 81 is provided with an open / close switching valve 71. The pump 30 is controlled by the control device 50, the feeding amount of the coating liquid per unit time is controlled, and the coating liquid is supplied to the applicator 10. When the coating liquid is supplied to the applicator 10 by the pump 30, the coating liquid is discharged from the discharge port 11 of the applicator 10. The pump 30 can also suck the coating liquid on the applicator 10 side by performing an operation opposite to the operation for supplying the coating liquid. As will be described later, this suction operation is performed during the replenishment of the coating liquid to the pump 30 and the control mode (No. 2).

  The coating device 5 further includes a tank (first tank) 35 that stores the coating liquid. The tank 35 is connected to the pump 30 through a pipe 83 extended from the pipe 81. The pipe 83 is provided with an open / close switching valve 73. The volume of the coating liquid that can be stored in the tank 35 is larger than the capacity of the pump 30, and the coating liquid stored in the tank 35 becomes a coating liquid for replenishing the pump 30.

The pressure applying device 40 includes a tank (second tank) 41 and a pressure regulator 42. The tank 41 stores a coating liquid and is connected to the applicator 10 through a pipe 82. The pipe 82 is provided with an open / close switching valve 72, and the coating liquid can flow between the tank 41 and the applicator 10 (reservoir 13) when the valve 72 is open. The valve 72 allows the applicator 10 and the second tank 41 to communicate and be blocked. The volume of the coating liquid that can be stored in the tank 41 is larger than the volume (volume) of the reservoir 13 of the applicator 10.
The pressure regulator 42 includes a regulator and changes the pressure applied to the coating liquid in the tank 41. The pressure adjuster 42 is controlled by the control device 50 and adjusts the pressure (internal pressure) of the coating liquid in the tank 41. Since the tank 41 and the applicator 10 are connected through the pipe 82, the pressure of the application liquid in the applicator 10 (reservoir 13) is controlled to a predetermined pressure by adjusting the pressure of the application liquid in the tank 41. can do. For example, by adjusting the pressure (gauge pressure) of the coating liquid in the tank 41 to a negative pressure, the pressure (gauge pressure) of the coating liquid in the applicator 10 (reservoir 13) can be made negative.

  Thus, in the present embodiment, the pressure regulator 42 adjusts the pressure of the coating liquid stored in the tank 41 so as to keep the pressure of the coating liquid in the applicator 10 at a predetermined value (negative pressure). These pressure regulators 42 and tanks 41 constitute a pressure applying device 40 that applies pressure (negative pressure) to the coating liquid in the applicator 10.

  The coating apparatus 5 having the above configuration includes a pump control line L1 and a pressure control line L2 that are connected to the applicator 10 respectively. The pump control line L1 includes pipes 81 and 83, valves 71 and 73, a pump 30, and a first tank 35. The pressure control line L2 includes a pipe 82, a valve 72, a second tank 41, and a pressure regulator 42. One or both of the pump control line L1 and the pressure control line L2 are selectively used in each of the application operation and the liquid application operation described later.

  The coating apparatus 5 of the present embodiment has two control modes for the coating operation and is alternatively employed. For this purpose, the computer program stored in the storage means of the control device 50 includes two control mode programs, which are selectively executed. The application operation is an operation of discharging the coating liquid from the discharge port 11 to the substrate 7 while performing relative movement between the substrate 7 and the applicator 10 by the moving means 20 (linear actuator 23).

  Below, the coating method performed with the coating device 5 provided with the said structure is demonstrated. This application method includes a liquid application operation for starting the adhesion of the application liquid to the substrate 7, and the application operation is performed following the liquid application operation.

[Control mode (1)]
3-5 is explanatory drawing explaining the coating method. In the following description, the valve 71 between the pump 30 and the applicator 10 is called a first valve 71, the valve 72 between the second tank 41 and the applicator 10 is called a second valve 72, and A valve 73 between the one tank 35 and the pump 30 is referred to as a third valve 73.

As shown in FIG. 3A, initial application of the coating liquid is performed from the applicator 10 (initial application step). For this purpose, the first valve 71 is opened and the pump 30 is operated to discharge a small amount of coating liquid from the discharge port 11. In this initial dispensing process, the applicator 10 does not exist on the substrate 7.
Next, the discharge port 11 of the applicator 10 is wiped off (wiping process: see FIG. 3B). At this time, the pump 30 is in a stopped state.
Next, the height position of the applicator 10 is set to a predetermined position with respect to the substrate 7 on the stage 9. The height adjustment of the applicator 10 is performed by the elevating actuator 24 (see FIG. 1). For example, the interval between the discharge port 11 and the coated surface 8 is set to several tens of μm. Further, the applicator 10 is moved by the linear actuator 23 (see FIG. 1) so that the ejection port 11 is positioned immediately above the application start position (the edge of the substrate 7) of the substrate 7 (preparation moving step).
Until this preparation movement process is completed, a process (hereinafter referred to as a pre-process) for setting the pressure of the coating liquid in the second tank 41 to be lower than the atmospheric pressure is performed.

In the pretreatment, the pressure of the coating liquid in the second tank 41 is set to a predetermined reduced pressure value (predetermined negative pressure value) in the pressure control line L2. This reduced pressure value (negative pressure value) is a value set in the control device 50 and is a value for making the pressure of the coating liquid in the applicator 10 a predetermined negative pressure value. Specifically, it is set to the same value as the negative pressure value generated in the coating liquid of the applicator 10 when performing the coating operation. The negative pressure (decompression) of the coating liquid in the second tank 41 is performed by the pressure regulator 42. The above processing is pre-processing.
By this pre-processing, the second valve 72 is closed until the preparatory movement step, and in this state, the pressure of the coating liquid in the second tank 41 does not affect the pressure of the coating liquid in the applicator 10. However, as will be described later, by opening the second valve 72, the negative pressure of the coating liquid in the second tank 41 is applied to the pressure of the coating liquid in the coating device 10, and the pressure of the coating liquid in the coating device 10 is instantaneously changed. Can be made negative pressure.

Next, the pump 30 is operated to supply the application liquid to the applicator 10 (see FIG. 4A). At this time, the supply amount of the coating liquid by the pump 30 is an extremely small amount, which is smaller than the supply amount at the time of the coating operation. Thereby, a small amount of coating liquid is discharged from the discharge port 11. Further, the supply of the coating liquid by the pump 30 increases the pressure of the coating liquid in the applicator 10 and approaches the atmospheric pressure.
When a small amount of the coating liquid discharged from the discharge port 11 contacts the substrate 7 (see FIG. 4B), the pressure in the applicator 10 rapidly decreases (returns to a negative pressure lower than atmospheric pressure). This is because the coating liquid in the applicator 10 is drawn out to the substrate 7 side due to the surface tension and capillary reduction (capillary) of the coating liquid in contact with the substrate 7.

  Since the pressure sensor 60 measures the pressure in the applicator 10 every moment, when the controller 50 detects a pressure drop in the applicator 10 caused by the contact of the coating liquid with the substrate 7, The valve 72 is opened (see FIG. 4C). Further, the supply of the coating liquid by the pump 30 is stopped. Thereby, in cooperation with the pretreatment being performed, the coating liquid in the applicator 10 is affected by the pressure of the coating liquid in the second tank 41, and the pressure of the coating liquid in the applicator 10 is Negative pressure. As a result, it is possible to prevent the coating solution from continuing to flow out of the applicator 10, and a bead 3 made of the coating solution is formed between the substrate 7 and the discharge port 11 (see FIG. 4C).

The steps shown in FIGS. 4A to 4C are the liquid application operation (liquid application process). In the liquid application operation, the control device 50 performs the following control as described above. That is, for the liquid application operation for starting the adhesion of the coating liquid to the substrate 7, the pump 30 supplies the coating liquid to the applicator 10, and this supply increases the pressure of the coating liquid in the applicator 10, and then When the pressure drop is detected by the pressure sensor 60, the supply of the coating liquid by the pump 30 is stopped. Further, in the present embodiment, the application liquid is applied by the pump 30 with the pump 30 in a state where the communication between the applicator 10 and the second tank 41 is blocked by the second valve 72 (that is, the second valve 72 is closed). After the pressure is detected by the pressure sensor 60, the supply of the coating liquid by the pump 30 is stopped and the second valve 72 is operated (that is, the second valve 72 is opened). The second tank 41 and the applicator 10 are connected.
According to this liquid application operation, once the application liquid is supplied from the pump 30 to the applicator 10, the pressure of the application liquid in the applicator 10 is increased, and thereby the application liquid is discharged from the discharge port 11. . When the coating solution comes into contact with the substrate 7, the coating solution in the applicator 10 is further drawn out by the surface tension of the coating solution, thereby reducing the pressure in the applicator 10. Therefore, when this pressure drop is detected by the pressure sensor 60, the supply of the coating liquid by the pump 30 is stopped to prevent excessive coating liquid from adhering to the substrate 7 during the liquid application operation. It becomes possible. Further, by opening the second valve 72 and allowing the second tank 41 and the applicator 10 to communicate with each other, the coating liquid discharged from the discharge port 11 adheres to the substrate 7 and then the coating liquid in the applicator 10 is removed. It becomes possible to keep the pressure at a constant value (negative pressure).

  When the liquid application operation is performed as described above and the pressure of the coating liquid in the applicator 10 becomes negative due to the influence of the pressure of the coating liquid in the second tank 41 (when both pressures are equal), the second valve 72 is turned on. close up. Then, as shown in FIG. 5A, an application operation (application process) is performed. In this step, the movement of the applicator 10 in the horizontal direction is started by the moving means 20 (linear actuator 23), and supply of the coating liquid by the pump 30 is started. Then, the application liquid is supplied by the pump 30 while moving the applicator 10 in the horizontal direction.

In this embodiment, the moving speed of the applicator 10 is constant. Here, since the substrate 7 is circular, as described above (see FIG. 2), in the applicator 10 (discharge port 11), the portion where the substrate 7 exists immediately below and the substrate 7 exists immediately below. In other words, the range of each of these portions varies depending on the relative positions of the substrate 7 and the applicator 10. 2B, the coating liquid is discharged from the portion where the substrate 7 exists as shown in FIG. 2B, whereas the substrate 7 does not exist as shown in FIG. The coating liquid is not discharged at the portion.
Accordingly, in order to apply the coating liquid to the circular substrate 7 by moving the applicator 10 at a constant speed and form a coating film with a constant film thickness on the substrate 7, it should be discharged from the discharge port 11. The amount of the coating liquid varies depending on the position of the applicator 10 with respect to the substrate 7. Therefore, a control (quantitative discharge control) is performed in which an amount necessary for forming a coating film with a constant film thickness on the substrate 7 is not sent out from the pump 30 by a constant amount. That is, the amount of the coating liquid delivered from the pump 30 is set to an amount corresponding to the coating liquid amount (the necessary amount) that changes in accordance with the change in the width direction (shape change) of the substrate 7. The width direction of the substrate 7 is a direction that coincides with the longitudinal direction of the applicator 10 (discharge port 11).

  The amount of the coating liquid delivered from the pump 30 as described above is set in a computer program stored in the storage means of the control device 50. That is, the computer program includes data in which the relative position between the applicator 10 and the substrate 7 and the discharge amount (supply amount) of the coating liquid at that position are associated with each other. Based on this, the control device 50 operates the pump 30 and the moving means 20. As a result, a set amount of the coating liquid can be discharged from the applicator 10 without using the measurement value of the pressure sensor 60, and a constant film thickness can be formed on the substrate 7. In addition, the said discharge amount based on a position is a value calculated | required previously according to the coating film to form, and changes with coating films.

  Further, at the start of the coating operation, the pre-processing is executed, the pressure of the coating liquid in the coating device 10 is set to a negative pressure, and the pump 30 is used for the amount of coating liquid discharged from the discharge port 11. Therefore, the pressure in the applicator 10 is maintained at a constant value while maintaining a negative pressure during the application operation.

  As described above, in the control mode (part 1), the following control is performed by the control device 50 during the coating operation. That is, during the application operation, control is performed to supply the application liquid from the pump 30 to the applicator 10 according to the amount of the application liquid consumed by being discharged from the discharge port 11. This control facilitates the control of capillary coating for forming a coating film having a desired uniform thickness on the substrate 7 (surface to be coated 8) while maintaining the coating liquid in the applicator 10 at a negative pressure.

Then, as shown in FIG. 5B, when the applicator 10 (discharge port 11) reaches the application end position (the edge of the substrate) of the substrate 7, the supply of the application liquid by the pump 30 is stopped.
When the supply is stopped, although not shown, the applicator 10 is raised by the elevating actuator 24, the first valve 71 is closed, and the third valve 73 is opened. The pump 30 sucks and replenishes the coating liquid in the first tank 35 and prepares for the next coating. The substrate 7 coated with the coating liquid is removed from the stage 9 and carried to a dryer.

  As described above, in the control mode (part 1), the control for supplying the coating liquid consumed by the coating by the pump 30 is performed. At the time of this control, the second valve 72 of the pressure control line L2 is in a closed state, and the liquid is supplied only by the pump 30 of the pump control line L1. The pump 30 supplies the application liquid to the applicator 10 by an amount corresponding to a preset discharge amount of the application liquid from the applicator 10. At this time, the amount of the application liquid supplied to the applicator 10 is drawn out of the applicator 10 by the shearing force generated in the bead 3 of the application liquid between the substrate 7 and the applicator 10 due to the capillary action and the application operation. The amount is set to be smaller than the amount of the coating liquid to be applied, and this enables supply while suppressing discharge. As a result, the coating liquid is supplied by the pump 30, but in the applicator 10, a force for drawing the coating liquid to the outside works from the discharge port 11, and the coating liquid in the applicator 10 is in a negative pressure state. To be kept.

[Control mode (2)]
An initial dispensing step for initial dispensing of the coating liquid from the applicator 10, a wiping step for wiping the ejection port 11 of the applicator 10, and an ejection port immediately above the coating start position (the edge of the substrate 7) of the substrate 7 The preparatory movement process for moving the applicator 10 so that 11 is positioned includes the initial putting out process (FIG. 3A), the wiping process (FIG. 3B), and the preparation in the control mode (part 1). This is performed in the same manner as the moving step (FIG. 3C).
Moreover, it is the same as that of control mode (the 1) also to perform the said pre-processing until a preparation movement process is completed.
Then, a liquid application operation (liquid application process) for starting adhesion of the coating liquid to the substrate 7 is started. This liquid application operation is the same as the liquid application operation (liquid application step) in the control mode (part 1) shown in FIGS.
A description of the same points as in the control mode (No. 1) is omitted here.

When the liquid application operation is completed, a bead 3 made of a coating liquid is formed between the substrate 7 and the discharge port 11 (see FIG. 4C). After the liquid application operation is performed and the second valve 72 is opened to connect the second tank 41 and the applicator 10, the application liquid discharged from the discharge port 11 adheres to the substrate 7. The pressure of the coating liquid inside is kept at a constant value (negative pressure).
When the pressure of the coating liquid in the applicator 10 becomes negative due to the influence of the pressure of the coating liquid in the second tank 41, the second valve 72 is closed in the control mode (No. 1) (see FIG. 5A). In the control mode (part 2), the second valve 72 is kept open (see FIG. 6A). And application | coating operation | movement (application | coating process) is performed. In this process, the horizontal movement of the applicator 10 by the moving means 20 (linear actuator 23) is started, and the application liquid connected to the second tank 41 is controlled by controlling the pressure of the application liquid in the second tank 41. The pressure of the coating liquid in the container 10 is maintained at a constant value (a constant negative pressure value), and the pump 30 can supply the coating liquid to the coating apparatus 10. That is, while the applicator 10 is moved in the horizontal direction by the moving means 20, the pressure control by the second tank 41 and the pressure regulator 42 and the supply control in which the application liquid is supplied by the pump 30 are performed by the control device 50. Done.

The pressure control performed in the coating operation is a control for keeping the pressure of the coating liquid in the second tank 41 at a set value so that the pressure of the coating liquid in the applicator 10 becomes a predetermined (constant) negative pressure value. It is.
The supply control performed in the application operation is feedback control based on the measurement value of the pressure sensor 60. That is, the control device 50 detects a change in the measured value of the pressure sensor 60 every moment, and when the amount of change exceeds a threshold value (allowable value), the pump 30 supplies or sucks the coating liquid. More specifically, when the measured value by the pressure sensor 60 decreases and the change amount exceeds the threshold value, the operation of supplying the coating liquid is performed, and the measured value increases and the change amount exceeds the threshold value. The operation of sucking the coating liquid is performed. In this way, the control device 50 further stabilizes the pressure of the coating liquid in the applicator 10 by adjusting the supply or suction of the coating liquid by the pump 30.

Also in the control mode (part 2), the moving speed of the applicator 10 is constant. Here, since the substrate 7 is circular, as described above (see FIG. 2), in the applicator 10 (discharge port 11), the portion where the substrate 7 exists immediately below and the substrate 7 exists immediately below. In other words, the range of each of these portions varies depending on the relative positions of the substrate 7 and the applicator 10. 2B, the coating liquid is discharged from the portion where the substrate 7 exists as shown in FIG. 2B, whereas the substrate 7 does not exist as shown in FIG. The coating liquid is not discharged at the portion.
Therefore, in order to apply the application liquid to the circular substrate 7 by moving the applicator 10 at a constant speed and form a constant film thickness on the substrate 7, the application liquid to be discharged from the discharge port 11 is changed. The amount varies depending on the position of the applicator 10 relative to the substrate 7. Therefore, the pump 30 does not send out a constant amount of coating liquid, but controls to send out an amount necessary to form a coating film with a constant film thickness on the substrate 7. Further, in this control mode (part 2), as described above, the supply or suction of the coating liquid by the pump 30 is controlled based on the measured value of the pressure sensor 60, and the pressure in the applicator 10 is adjusted. (Constant) That is, the amount of the coating liquid sent out from the pump 30 is an amount corresponding to the amount of the coating liquid that changes in accordance with the change in the width direction (shape change) of the substrate 7 and the measurement by the pressure sensor 60. By performing the control based on the value, it is the sum of the amount of coating liquid supplied or sucked.
In the control mode (part 1), the amount of the coating liquid sent out from the pump 30 is set in a computer program stored in advance in the control device 50, but in the control mode (part 2), the amount is supplied from the pump 30. The amount of the coating liquid changes every moment according to the measurement value of the pressure sensor 60.

As described above, the following control is performed by the control device 50 during the coating operation. That is, during the coating operation, the pressure of the coating solution in the coating device 10 is controlled by the pressure applying device 40 (second tank 41 and pressure regulator 42) in order to maintain the coating solution in the coating device 10 at a negative pressure. At the same time, based on the measurement result of the pressure sensor 60, adjustment control including supply and suction of the coating liquid by the pump 30 is performed.
In addition, when the coating operation is started, the pre-processing is executed, and the pressure of the coating liquid in the coating device 10 is set to a negative pressure. Even when the coating operation is started, the coating is performed by the pressure applying device 40. Since the negative pressure of the applicator 10 is maintained and the control by the pump 30 is also performed based on the measurement result of the pressure sensor 60, the pressure of the coating liquid of the applicator 10 is maintained at a constant value while maintaining the negative pressure. .
By this control, pressure control for keeping the pressure (negative pressure) in the applicator 10 constant is performed, and control of capillary application for forming a uniform-thickness coating film on the substrate 7 (application surface 8) is performed. It becomes easy.

In this embodiment, as shown in FIG. 6B, on the stage 9, in addition to the substrate 7, a dummy plate 65 is adjacent to the edge of the substrate 7 (the edge on the coating end side). The applicator 10 is moved along the substrate 7, passes through the application end position (the edge of the substrate 7) of the substrate 7, and continues to discharge the application liquid until it reaches the dummy plate 65. When the applicator 10 (discharge port 11) reaches a predetermined position of the dummy plate 65, the adjustment (discharge) of the coating liquid by the pump 30 is stopped and the second valve 72 is closed.
And although not shown in figure, the applicator 10 is raised by the raising / lowering actuator 24, the 1st valve | bulb 71 is closed, and the 3rd valve | bulb 73 is opened. The pump 30 sucks and replenishes the coating liquid in the first tank 35 and prepares for the next coating. The substrate 7 coated with the coating liquid is removed from the stage 9 and carried to a dryer.
The dummy plate 65 may be omitted and the coating operation may be terminated as in the control mode (part 1), or the dummy plate 65 may be employed in the control mode (part 1).

In this control mode (part 2), control is performed with both the first valve 71 of the pump control line L1 and the second valve 72 of the pressure control line L2 being opened. When a pressure drop is detected by the pressure sensor 60 provided in the applicator 10 during the application operation, a small amount of liquid is supplied to the applicator 10 by the pump 30, so that the pressure in the applicator 10 is restored to the original pressure. The setting value can be restored. By performing feedback control of this operation in a short time, the pressure in the applicator 10 can be kept constant.
The liquid supply amount by the pump 30 may be an amount corresponding to the predicted consumption of the coating liquid, but further feedback control when a difference between the set liquid supply amount and the actual liquid consumption occurs. It is preferable that the value is adjusted.

[Control Mode (Part 1) and (Part 2)]
In the coating device 5 having the above-described configuration, the control device 50 can selectively employ one or both of the pump control line L1 and the pressure control line L2 according to the coating conditions. That is, the control mode (part 1) or the control mode (part 2) is alternatively selected according to the application conditions. Application conditions include, for example, the film thickness to be formed on the substrate 7, the application speed (movement speed of the applicator 10), and the like.

  The liquid application operation (liquid application method at the start of application) performed in each of the control modes (Part 1) and (Part 2) will be further described. As shown in FIG. 4A, the applicator is supplied by supplying the coating liquid from the pump 30 with the second valve 72 of the pressure control line L2 closed and the first valve 71 of the pump control line L1 opened. A small amount of coating solution is slowly discharged from 10. At this time, the pressure in the applicator 10 changes from the negative pressure state to the positive pressure direction. When the coating liquid discharged from the applicator 10 adheres to the substrate 7 (see FIG. 4B), the coating liquid (bead 3) connecting between the applicator 10 and the substrate 7 is spread by the surface tension and spreads. By trying to do so, a force for pulling out the coating liquid from the applicator 10 is generated. By this force, the pressure in the applicator 10 changes in the negative pressure direction. When such a pressure change in the applicator 10 is detected by the pressure sensor 60, switching in the pressure control line L2 and the pump control line L1 is performed as follows.

That is, based on the pressure change in the applicator 10, the pump 30 is stopped and the second valve 72 of the pressure control line L2 is opened (see FIG. 4C). Thereby, the pressure in the applicator 10 becomes a pressure set in advance by the pressure control line L2 (second tank 41). At this time, by controlling the time from the pressure change to the stop of the supply of the coating liquid by the pump 30 and the time from the pressure change to the opening of the second valve 72 being a predetermined time set by a timer. The amount of the coating liquid discharged from the applicator 10 at the start of coating can be controlled.
When coating thickness control is performed by the pump 30 after the second valve 72 is opened (control mode (part 1)), the second valve 72 is closed again, and the coating liquid is supplied by the pump 30. When coating thickness control is performed by pressure control (control mode (part 2)), the second valve 72 is opened as it is, and constant pressure control according to the set pressure is performed.

  Further, when the application liquid is deposited at the application start portion of the substrate 7, the application liquid is supplied by the pump 30 so that the amount of the application liquid to be discharged out of the applicator 10 by the capillary phenomenon is minimized. To the limit. In addition, by detecting the liquid application timing from the pressure change of the applicator 10, the liquid can be reliably applied even when a small amount of the liquid is discharged, and a stable film thickness at the start of application can be obtained. Become.

As described above, in each of the two control modes, the control device 50 supplies the application liquid from the pump 30 to the applicator 10 while maintaining the application liquid in the applicator 10 at a negative pressure during the application operation. Control for. According to this configuration, during the coating operation, the amount of the coating liquid supplied to the coating device 10 can be controlled to a predetermined amount by the pump 30, and the coating liquid discharged from the coating device 10 to the substrate 7 can be controlled. The amount of the coating liquid that is about to be ejected from the ejection port 11 to the outside of the applicator 10 due to surface tension and capillary action can be suppressed. Accordingly, the capillary coating is performed so that the coating liquid can be discharged downward from the discharge port 11 to form a coating film having a desired thickness (uniform thickness) on the substrate 7 (surface 8). Can do.
Then, by applying the coating method (capillary coating) executed by the coating device 5 to the product manufacturing method, a high-quality product in which a coating film having a uniform film thickness is formed on the entire surface can be stabilized. And can be manufactured.

〔Applicable condition〕
As a coating liquid applicable to the coating apparatus 5 demonstrated above, a viscosity is 1-100000 mPa * S and it is preferable from a coating property that it is Newtonian, However, It can apply also to the coating liquid which has thixotropy. Specific examples of the coating solution that can be applied include a black matrix for color filters, a coating solution for forming RGB color pixels, a resist solution, an overcoat material, a column forming material, and a coating solution for an adhesive layer for semiconductors. , Flattening coating liquid, protective film coating liquid, resist liquid, colored layer coating liquid, fluorescent light emitting layer coating liquid, TFT positive resist, and the like.
As the substrate (member to be coated) 7, in addition to a silicon wafer or glass, a metal plate such as aluminum, a ceramic plate, a film, or the like may be used. The shape of the substrate (member to be coated) 7 may be a rectangular shape, or may be a non-rectangular shape such as a circle. Furthermore, a plurality of non-rectangular substrates may be applied simultaneously to the substrates 7 by being arranged in parallel along the longitudinal direction of the applicator 10. Further, as application conditions to be used, the application speed is 0.1 to 100 mm / second, more preferably 0.5 to 20 mm / second, and the gap between the discharge port 11 of the applicator 10 and the application surface 8 of the substrate 7. The (slit gap) is 50 to 1000 μm, more preferably 100 to 500 μm, and the coating thickness is 0.5 to 100 μm, more preferably 1 to 50 μm in a wet state.

[Example 1]
An embodiment when the control mode (part 1) is employed will be described.
The polyimide was apply | coated with respect to the circular silicon wafer of diameter (phi) 100x thickness 0.53mm with the coating device 5 shown in FIG. The polyimide had a viscosity of 4400 mPa · s and a solid content of 19%. As the applicator 10, a discharge port 11 having a length in the application width direction (longitudinal direction, Y direction) of 150 mm and a gap (length in the X direction) of the discharge port 11 of 0.4 mm was used. In order to measure the pressure of the coating solution in the reservoir 13 of the applicator 10, a pressure sensor 60 was provided.
Then, by controlling the discharge amount by the pump 30, the discharge amount corresponding to the change in the coating width is determined so that the wet film thickness becomes 40 μm, the pressure in the applicator 10 at the start of coating is −20 Pa (gauge pressure), and the coating speed Application was performed under the condition of 0.5 mm / second.
The coated substrate 7 was dried on a hot plate at 150 ° C. for 10 minutes. When the coating state was observed after drying, a coating film with a thickness of 8 μm was formed on the entire surface area of φ100, and the film thickness unevenness was ± 3% within a range of 96 mm in diameter excluding the 2 mm range of the coating outer peripheral portion. It was as good as below.

[Example 2]
Another embodiment when the control mode (part 2) is employed will be described.
A color resist was applied to a circular silicon wafer having a diameter of φ100 × thickness of 0.53 mm by the coating apparatus 5 shown in FIG. The color resist had a viscosity of 4 mPa · s and a solid concentration of 15%. As the applicator 10, a discharge port 11 having a coating width direction (longitudinal direction, Y direction) length of 150 mm and a gap (X direction length) of the discharge port 11 of 0.2 mm was used. In order to measure the pressure of the coating solution in the reservoir 13 of the applicator 10, a pressure sensor 60 was provided.
And the correction of the pressure fluctuation in the applicator 10 was implemented by the pump 30 as discharge amount control by constant pressure control.
Under the conditions that the pressure in the applicator 10 at the start of application is −180 Pa (gauge pressure) and the application speed is 2 mm / second, the application operation is performed while performing feedback control on the pump 30 so that the fluctuation of the discharge pressure is within 5 Pa as a threshold value. went.
The coated substrate 7 was vacuum dried to reach 65 Pa in 25 seconds for 60 seconds, and then further dried on a hot plate at 120 ° C. for 10 minutes.
When the coating state was observed after drying, a coating film having a thickness of 800 nm was formed on the entire surface area of φ100, and the film thickness unevenness was ± 3% within a range of 96 mm in diameter excluding the 2 mm range of the coating outer peripheral portion. It was as good as below.

When the direction in which the application liquid is discharged from the applicator 10 (discharge port 11) is downward as in the present embodiment (in the case of downward capillary application), the significance of setting the application liquid in the applicator 10 to a negative pressure is The following (1) and (2).
(1) To prevent the coating liquid in the applicator 10 from freely flowing out of the discharge port 11 (by its own weight).
(2) To adjust the film thickness formed on the substrate 7.

  In addition, you may comprise the coating device 5 so that the discharge direction of a coating liquid may become upward (it includes diagonally upward). In this case (in the case of upward capillary application), although not shown (explained with reference to FIG. 1), in the same state as in the case where the discharge port 11 faces downward, the coating liquid is applied between the discharge port 11 and the substrate 7 thereabove. A bead is formed so that the coating liquid in the vicinity of the discharge port 11 (slit channel 12) has a negative pressure. During this operation, the pressure value applied to the tank 41 by the pressure regulator 42 is a pressure value calculated based on the application liquid in the vicinity of the discharge port 11 having a predetermined negative pressure, and may not be a negative pressure. . In this state, the coating operation is performed. That is, during the coating operation, the control device 50 executes control for supplying the coating solution from the pump 30 to the coating device 10 while making the coating solution near the discharge port 11 in the coating device 10 have a negative pressure. Specifically, control is performed to supply the application liquid from the pump 30 to the applicator 10 according to the amount of the application liquid discharged from the discharge port 11. That is, the application operation based on the control mode (part 1) is performed. The control device 50 controls the pressure of the coating liquid in the applicator 10 by the pressure applying device 40 in order to maintain the coating liquid in the vicinity of the discharge port 11 in the applicator 10 at a negative pressure, and a pressure sensor 60. It has a function to perform adjustment control of the coating liquid by the pump 30 based on the measurement result. That is, the coating operation based on the control mode (part 2) can also be performed. In the case of this upward capillary coating, the significance of making the coating solution in the vicinity of the discharge port 11 in the applicator 10 negative is the above (2).

[Appendix]
The embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of rights of the present invention is not limited to the above-described embodiments, but includes all modifications within the scope equivalent to the configurations described in the claims.
In the above-described embodiment, the member to be coated is the sheet-like substrate 7, but it may be a continuous member instead of the sheet-like substrate.

5: Coating device 7: Substrate (coated member) 8: Surface to be coated 10: Coating device 11: Discharge port 12: Slit channel 13: Reservoir 20: Moving means 30: Pump 35: First tank 40: Pressure Giving device 41: Second tank 42: Pressure regulator 50: Control device 60: Pressure sensor 71: First valve 72: Second valve 73: Third valve 81: Piping 82: Piping 83: Piping

Claims (10)

It has a reservoir for storing the coating liquid, a discharge port for discharging the coating liquid, and a slit-like channel connecting the reservoir and the discharge port, and discharges the coating liquid from the discharge port to the member to be coated. An applicator to perform,
Moving means for relatively moving the applicator and the coated member in a direction parallel to the coated surface of the coated member;
A pump for supplying a coating liquid to the applicator;
During the coating operation in which the coating liquid is discharged from the discharge port to the member to be coated while performing the relative movement, the coating liquid is supplied from the pump to the coating device while the coating liquid in the coating device is set to a negative pressure. A control device for performing control to
A coating apparatus comprising:   The said control apparatus is a coating device of Claim 1 which performs control which supplies the coating liquid according to the quantity of the coating liquid discharged from the said discharge port from the said pump to the said applicator at the time of the said coating operation. A pressure applying device that applies pressure to the coating liquid in the applicator;
A pressure sensor for measuring the pressure of the coating liquid in the applicator, and
The control device controls the pressure of the coating liquid in the applicator by the pressure applying device to maintain the coating liquid in the applicator at a negative pressure, and based on the measurement result of the pressure sensor, the pump The coating apparatus according to claim 1, wherein adjustment control of the coating liquid is performed.   The controller supplies the application liquid to the applicator by the pump for the liquid application operation to start the application of the application liquid to the member to be applied, and the pressure of the application liquid in the applicator is supplied by the supply. 4. The coating apparatus according to claim 1, wherein when the pressure drop is detected after the increase, the supply of the coating liquid by the pump is stopped. 5. A tank connected to the applicator through a pipe and storing a coating liquid, and a pressure for adjusting the pressure of the coating liquid stored in the tank so as to keep the pressure of the coating liquid in the applicator at a predetermined value. A regulator, and a valve that enables communication and blocking of the applicator and the tank, and
When the control device detects a decrease in the pressure after supplying the coating liquid to the applicator by the pump in a state where communication between the applicator and the tank is blocked by the valve, The coating apparatus according to claim 4, wherein the supply of the coating liquid by the pump is stopped and the valve is operated to connect the tank and the applicator. The coating liquid is applied to the member to be coated from the discharge port of the applicator having a reservoir part for storing the coating liquid, a discharge port for discharging the coating liquid, and a slit-like channel connecting the reservoir part and the discharge port. Is a method for performing capillary coating by discharging
While relatively moving the applicator and the member to be coated in a direction parallel to the surface to be coated of the member to be coated, a coating operation for discharging the coating liquid from the discharge port to the member to be coated is performed.
In the application operation, the application liquid is supplied to the applicator from a pump connected to the applicator while applying a negative pressure to the application liquid in the applicator.   The coating method according to claim 6, wherein during the coating operation, a coating liquid corresponding to an amount of the coating liquid discharged from the discharge port is supplied from the pump to the applicator. The pressure of the coating liquid in the applicator is measured by a pressure sensor;
The pressure of the coating liquid in the applicator is controlled to maintain the coating liquid in the applicator at a negative pressure, and the adjustment of the coating liquid by the pump is performed based on the measurement result of the pressure sensor. Item 8. The coating method according to Item 6 or 7.   For the liquid application operation for starting the adhesion of the coating liquid to the member to be coated, the coating liquid is supplied to the applicator by the pump, and after increasing the pressure of the coating liquid in the applicator by the supply, The application | coating method as described in any one of Claims 6-8 which stops supply of the coating liquid by the said pump, if the fall of a pressure is detected. The applicator is connected to a tank for storing a coating solution through a pipe, and is provided with a valve that allows the applicator and the tank to communicate with and shut off.
The pressure of the coating liquid stored in the tank can be adjusted by a pressure regulator so as to keep the pressure of the coating liquid in the coating device at a predetermined value.
When the communication between the applicator and the tank is cut off by the valve, the application liquid is supplied to the applicator by the pump, and when the pressure drop is detected, the supply of the application liquid by the pump is performed. The coating method according to claim 9, wherein the tank is connected to the applicator by operating the valve.

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