JP5382920B2 - Pump device and coating device - Google Patents

Description

  The present invention relates to a pump device and a coating apparatus including the pump device.

A flat panel display such as a liquid crystal display or a plasma display uses a glass substrate in which a resist solution (coating solution) is uniformly applied (hereinafter referred to as a coating substrate). As an apparatus for manufacturing the coated substrate, for example, a coating apparatus described in Patent Document 1 is used.
As shown in FIG. 8, the coating apparatus includes a stage 51 on which the glass substrate 50 is placed, a slit-like nozzle 52 that moves along the glass substrate 50 and discharges the coating liquid onto the glass substrate 50, A pump 53 for feeding the coating liquid to the nozzle 52 is provided. Then, while moving the nozzle 52 along the glass substrate 50, the resist solution is discharged from the nozzle 52 onto the glass substrate 50 in a band shape. As a result, the resist solution is applied on the glass substrate 50 in the form of a film.

Various pumps 53 can be employed as the pump 53 used in such a coating apparatus. In the case of a piston pump, the pump includes, for example, a ball screw mechanism that changes the rotational motion of the motor into a linear motion. Yes. When this ball screw mechanism rotates, periodic fine vibration is generated by the rolling of the ball, and this fine vibration is transmitted to the pump main body, and pulsation is generated in the resist solution sent out from the pump main body. Further, when cogging of the motor occurs or slight vibration occurs at the meshing portion of the gear that decelerates the motor, pulsation may be superimposed on the resist solution.
As a result, the discharge pressure of the resist solution at the nozzle 52 fluctuates, the film thickness of the discharged resist solution changes periodically on the glass substrate 50, and uneven coating occurs. In particular, since the slight vibration transmitted to the resist solution is periodic, uneven coating also occurs with periodicity. When the coating unevenness has periodicity, it is particularly noticeable and is not preferable as the quality of the product.

JP 2008-212861 A (see FIG. 4)

  Therefore, in order to reduce the pulsation generated in the resist solution and suppress the coating unevenness generated on the glass substrate 50, the coating apparatus described in Patent Document 1 detects the pressure of the resist solution fed from the pump 53. A pressure sensor 54, a calculator 55 that generates a reverse phase wave from the detected change in pressure and outputs the reverse phase wave at a predetermined timing, and a pressure based on the output reverse phase wave are sent from the pump 53. And a pressurizer 56 for applying to the resist solution.

However, in the case where the pressure of the resist solution is measured after the resist solution is sent out from the pump 53 and control is performed so as to pressurize the resist solution, the pressure sensor 54 and the pressurizer 56 are not connected. In addition, there are many delay elements and mechanical nonlinear elements due to the elasticity of the flow path (pipe by a tube and a filter (not shown)), and the control becomes complicated. In addition, the vibration of the pipe between the pressure sensor 54 and the pressurizer 56 becomes a disturbance, diverges due to the phase delay, and the control becomes unstable. Thus, in the case of the configuration of Patent Document 1, it is difficult to increase the control gain, and it is considered difficult to actually operate.
Note that the pulsation in the resist solution is not limited to the cylinder pump as described above, but is also the same in other types of pumps, and the slight vibration generated by driving the pump is a cause of uneven coating. It has become.
Therefore, the present invention can suppress the occurrence of pulsation in the applied coating liquid, and can prevent the occurrence of uneven coating on the substrate, and also suppress the occurrence of uneven coating. An object of the present invention is to provide a coating apparatus that can be easily controlled.

The present invention is a pump device for delivering a coating liquid to a nozzle of a coating apparatus that discharges the coating liquid from a nozzle to form a coating film, the coating liquid chamber storing the coating liquid, and coating the coating liquid chamber A pump body having a discharge port for discharging the liquid; a drive unit that is driven to discharge the coating liquid from the discharge port; and the driving unit that drives the coating liquid in the coating liquid chamber An actuator that performs an operation in the pump main body to suppress the pressure fluctuation to be generated, and the pump main body includes a coating liquid chamber that stores the coating liquid by a flexible partition film, and an indirect liquid chamber that stores the indirect liquid. The pump case is divided into two parts, and when the driving unit is driven, the partition film is deformed by pressurizing the indirect liquid, and the volume of the coating liquid chamber is reduced. Chromatography data is characterized by having a vibration generating portion for vibrating the indirect liquid for suppressing operation of the pressure fluctuations.

  According to the present invention, even if the pressure fluctuation is caused in the coating liquid in the coating liquid chamber of the pump body due to the driving unit being driven, the actuator performs the operation for suppressing the pressure fluctuation in the pump body. It is possible to prevent pulsation from occurring in the coating liquid to be delivered. And since an actuator performs the operation | movement which suppresses the said pressure fluctuation in the pump main body used as the generation part (generation source) of the said pressure fluctuation, it becomes possible to simplify control of an actuator.

Further, the pump body of the pump device of the present invention has a pump case that is partitioned into a coating liquid chamber for storing the coating liquid and an indirect liquid chamber for storing an indirect liquid by a flexible partition film, and the driving When part is driven, configuration der is, the actuator volume of the coating liquid chamber to deform the partition membrane by pressurizing the indirect liquid is reduced, the vibration to the indirect liquid for suppressing operation of the pressure fluctuations and a vibration generating unit to give.
With this configuration , when the driving unit is driven, the partition film is deformed by pressurizing the indirect liquid, the volume of the coating liquid chamber is reduced, and the coating liquid in the coating liquid chamber can be sent out to the nozzle. At this time, when the driving unit is driven, pressure fluctuation occurs in the indirect liquid, and this pressure fluctuation is transmitted to the coating liquid through the partition wall film, so that the pressure fluctuation tends to occur in the coating liquid. However, since the vibration generation unit of the actuator applies vibration to the indirect liquid in order to cancel the pressure fluctuation of the indirect liquid as an operation for suppressing the pressure fluctuation, it is possible to prevent the pressure fluctuation from being transmitted to the coating liquid. It is possible to prevent pulsation from occurring in the coating liquid sent to the nozzle.

Further, in this configuration, the pump device performs, on the vibration generating unit, a sensor that detects the pressure of the indirect liquid and an operation that gives the indirect liquid a vibration having a phase opposite to the fluctuation of the pressure detected by the sensor. It is preferable to further include a phase inversion unit that generates a signal for generating the signal.
In this case, when the sensor detects a change in the pressure of the indirect liquid, the phase inversion unit generates a signal that causes the vibration generating unit to perform an operation that gives the indirect liquid a vibration having a phase opposite to the pressure change. When the vibration generating unit operates based on the signal, the pressure fluctuation generated in the indirect liquid can be canceled.

The coating apparatus of the present invention includes a stage on which the substrate is placed, a nozzle that moves relative to the substrate and discharges the coating liquid to the substrate, and the pump device that sends the coating liquid to the nozzle. It is characterized by.
According to the present invention, even if the pressure fluctuation is caused in the coating liquid in the pump main body due to the operation of the pump device, the actuator provided in the pump device performs the operation of suppressing the pressure fluctuation, so that it is sent to the nozzle. It is possible to prevent pulsation from occurring in the applied coating solution, and to suppress the occurrence of uneven coating on the substrate coated with the coating solution. And since the said actuator performs the operation | movement which suppresses the said pressure fluctuation in the pump main body used as the generation | occurrence | production part (generation source) of the said pressure fluctuation, it becomes possible to simplify control of an actuator.

  According to the pump device of the present invention, since the actuator performs an operation for suppressing pressure fluctuations that are to occur in the coating liquid, it is possible to prevent pulsation from occurring in the coating liquid sent to the nozzle. According to the coating apparatus of the present invention, since the pump device is provided, it is possible to suppress the occurrence of uneven coating on the substrate on which the coating liquid has been applied. As a result, it is possible to improve the quality of the coated substrate manufactured by applying the coating liquid to the substrate. In addition, since the actuator performs the operation for suppressing the pressure fluctuation in the pump main body that is the pressure fluctuation generating unit, the control of the actuator can be simplified.

It is a perspective view which shows one Embodiment of the coating device of this invention. It is a schematic block diagram of a coating device. It is sectional drawing explaining schematic structure of a pump apparatus. It is sectional drawing explaining schematic structure of a pump apparatus. It is sectional drawing explaining the one part schematic structure of a pump main body. It is a schematic block diagram which shows other embodiment of a coating device. It is a schematic block diagram which shows other embodiment of a coating device. It is a schematic block diagram of the conventional coating device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing an embodiment of a coating apparatus of the present invention. This coating apparatus applies a liquid material such as a chemical solution or a resist (hereinafter also referred to as a coating solution) to the thin plate-like substrate 12. The coating apparatus includes a base 13, a stage (holding base) 14 on which the substrate 12 is placed, and a coating unit 15 that can move in a specific direction with respect to the stage 14. In the following description, the direction in which the coating unit 15 moves is the X-axis direction, the direction orthogonal to this in the horizontal plane is the Y-axis direction, and the vertical direction orthogonal to both the X-axis direction and the Y-axis direction is the Z-axis direction. And

A stage 14 is installed on the base 13, and rails 17 are provided on both sides of the stage 14 in the Y-axis direction. The application unit 15 is placed on the rail 17, and the application unit 15 moves along the rail 17 in the X-axis direction.
The stage 14 can place the loaded substrate 12 on the upper surface thereof, and can hold the substrate 12 by sucking the substrate 12 with a pump (not shown).
The coating unit 15 is for coating the coating liquid on the substrate 12 placed on the stage 14. The coating unit 15 extends along the Y-axis direction and flows out the coating liquid. 22 and unit support portions 23 provided at both end portions.

  The unit support portion 23 includes an elevating mechanism 24 that moves the base portion 22 up and down in the Z-axis direction and a traveling mechanism 25 that travels the base portion 22 in the X-axis direction. The lifting mechanism 24 and the traveling mechanism 25 are controlled in operation by a control device 26 (see FIG. 2) provided in the coating device. The control device 26 is composed of a computer including arithmetic means including a CPU, storage means such as a ROM, RAM, and HDD for storing programs and data, an input / output interface for inputting / outputting signals to / from the outside, and the like. . Each functional unit can be provided by executing various programs stored in the storage unit by the calculation unit.

[First embodiment]
FIG. 2 is a schematic configuration diagram of the coating apparatus of FIG. In the base part 22, a nozzle 10 that discharges the coating liquid is formed on the surface facing the stage 14. The nozzle 10 has a slit shape extending in the Y-axis direction (the direction orthogonal to the paper surface), and can discharge the coating liquid supplied to the base 22 through the nozzle 10 onto the surface of the substrate 12. As the coating unit 15 moves in the X-axis direction, the nozzle 10 moves in the same direction along the substrate 12 on the stage 14.

  On the upstream side of the nozzle 10, a tank 2 for storing the coating liquid and a pump device are provided. The pump device includes a pump body 1 and a drive unit (a plunger drive unit 33 described later). The tank 2 and the pump main body 1, and the pump main body 1 and the base part 22 are respectively connected by pipes (tubes) through which the coating liquid flows. When the driving unit is driven, the coating liquid in the tank 2 is supplied to the pump body 1, the coating liquid in the pump body 1 is pumped to the base part 22, and the coating liquid supplied to the base part 22 is a nozzle. 10 is discharged onto the substrate 12.

  The pump device of the embodiment of FIG. 2 is a syringe pump, and includes a pump body 1 having a cylinder 31 and a plunger 32 and a plunger drive unit 33 as shown in FIGS. 3 and 4. The plunger 32 has a head 32 a and a shaft portion 32 b, and the plunger 32 is accommodated in the cylinder 31. When the plunger drive unit 33 moves the plunger 32, the coating liquid can be sucked and sent out. Further, the cylinder 31 is provided with a film-like sealing member 34 that divides the inside thereof into an application liquid chamber a and a space chamber b in the axial direction. When the plunger 32 moves, the coating liquid is sucked into the coating liquid chamber a and further sent out from the coating liquid chamber a.

The cylinder 31 has a cylindrical shape extending in a uniaxial direction, and the upper housing 31a and the lower housing 31b are connected by a flange portion 31c. A suction port 31d and a discharge port 31e are formed in the upper housing 31a. The coating liquid can be sucked and sent into the cylinder 31 through the suction port 31d and the discharge port 31e. That is, as shown in FIG. 3, when the plunger 32 moves to the base side (lower side in FIG. 3) of the cylinder 31, the application liquid is taken from the tank 2 of FIG. 2 into the application liquid chamber a through the suction port 31d. Can do. On the other hand, as shown in FIG. 4, the plunger 32 moves to the front side (the upper side in FIG. 4) of the cylinder 31, so that the coating liquid in the coating liquid chamber a is transferred to the base 22 (nozzle 10) through the discharge port 31e. Can be sent out.
Further, a suction port 31f is formed in the lower housing 31b, and a suction pump (not shown) is connected to the suction port 31f. When the suction pump is operated to make the pressure in the space chamber b negative, the film-shaped sealing member 34 is sucked toward the space chamber b, and the film-shaped sealing member 34 can be brought into close contact with the head 32a.

  The film-shaped sealing member 34 is formed of a flexible material, for example, a polyester cloth coated with rubber, and is formed in a film shape having a substantially uniform thickness. The film-shaped sealing member 34 includes a clamped portion 34a that is clamped on the entire circumference of the flange portion 31c of the upper housing 31a and the lower housing 31b, and an attachment portion 34b that is attached in close contact with the distal end surface of the head 32a. It has the connection part 34c which connects the to-be-clamped part 34a and the attachment part 34b. The connecting portion 34c is a portion corresponding to the extra length portion, and a gap of a predetermined dimension is provided between the inner wall surface of the cylinder 31 and the outer peripheral surface of the head 32a, and the connecting portion 34c is curved in this gap. Contained in state. The connecting portion 34c is folded back at a position extending a predetermined dimension downward from the sandwiched portion 34a, is curved upward, extends a predetermined dimension upward, and is continuous with the attachment portion 34b. Even if the head 32a moves in the axial direction of the cylinder 31 by the connecting portion 34c, the film-shaped sealing member 34 can follow the movement of the head 82a. The liquid chamber a and the space chamber b are partitioned, and the coating liquid in the coating liquid chamber a is sealed.

  The plunger drive unit 33 moves the plunger 32 in the axial direction of the cylinder 31 at a constant speed. As a result, the delivery amount of the coating liquid from the pump body 1 is constant, the discharge amount of the coating liquid from the nozzle 10 is also constant, and the film thickness of the coating liquid is kept uniform. In this embodiment, the plunger drive unit 33 includes a servo motor 33a and a ball screw mechanism (not shown) that is rotated by the motor 33a. The servo motor 33a is controlled by the control device 26, and the plunger 32 moves forward and backward. Operation is controlled.

The pump device will be further described. As described above, the plunger drive unit 33 moves the plunger 32 to reduce the volume of the coating liquid chamber a in which the coating liquid is stored, and sends the coating liquid in the coating liquid chamber a to the nozzle 10. When the plunger drive unit 33 is driven, periodic fine vibration is generated in the ball screw portion, and this fine vibration is transmitted to the coating liquid in the coating liquid chamber a through the head 32a and the cylinder 31.
Therefore, the pump device performs an operation of canceling the pressure fluctuation of the coating liquid as an operation of suppressing the pressure fluctuation to be generated in the coating liquid in the coating liquid chamber a by driving the plunger driving unit 33. The actuator 7 is further provided.

The actuator 7 has a vibration generator 17. The vibration generator 17 is installed in the coating liquid chamber a so that vibration can be directly applied to the coating liquid in the coating liquid chamber a. A recess 31g is formed in the upper housing 31a, and the vibration generator 17 is installed in the recess 31g. A diaphragm 17a included in the vibration generator 17 is disposed on the opening side of the recess 31g. The membrane member 18 is provided so as to be in close contact with the diaphragm 17a and to close the recess 31g. The membrane member 18 is preferably a member having rigidity rather than a flexible member such as rubber in terms of vibration transmission. As the vibration generator 17, a voice coil type linear motor or a piezoelectric vibrator can be employed.
The vibration generator 17 vibrates the vibration plate 17a, so that vibration (pressure) can be directly applied to the coating liquid in the coating liquid chamber a through the film member 18. As described above, the vibration generator 17 applies a vibration to the application liquid that cancels out the pressure fluctuation that is about to occur in the application liquid in the application liquid chamber a by driving the plunger driving unit 33.

  In order to control the operation of the vibration generator 17, a pressure sensor 19 for detecting the pressure of the coating liquid in the coating liquid chamber a and a phase for generating a signal for causing the vibration generator 17 to perform a predetermined operation. An inversion unit 20 (see FIG. 2) is further provided. The detection surface of the pressure sensor 19 is exposed to the coating liquid chamber a. The phase inversion unit 20 is configured by, for example, a phase inversion circuit, and generates a signal for causing the vibration generator 17 to perform an operation of giving the application liquid a pressure fluctuation having a phase opposite to the pressure fluctuation detected by the pressure sensor 19. Is configured to do. The signal generated by the phase inverter 20 is amplified by the amplifier 21 and transmitted to the vibration generator 17.

  According to the above configuration, the pressure fluctuation occurs in the coating liquid in the coating liquid chamber a by driving the plunger driving unit 33. Therefore, when the pressure sensor 19 detects this pressure fluctuation, the phase inversion unit 20 generates a signal for causing the vibration generator 17 to perform an operation of giving the application liquid a pressure fluctuation having a phase opposite to the pressure fluctuation. . When the vibration generator 17 operates based on this signal, the pressure fluctuation generated in the coating liquid in the coating liquid chamber a can be canceled in the coating liquid chamber a. Therefore, the pulsation due to the drive of the plunger drive unit 33 is not generated in the coating liquid fed from the pump body 1. That is, the operation of canceling the pressure fluctuation of the coating liquid generated in the pump body 1 is performed before the coating liquid is sent out from the pump body 1. As a result, when the coating solution is discharged from the nozzle 10 onto the substrate 12, the coating solution has a uniform film thickness, and it is possible to suppress the occurrence of uneven coating on the substrate 12 to which the coating solution has been applied.

In addition, the diaphragm 17a of the vibration generator 17 of this embodiment is arranged so as to face the tip surface of the head 32a of the plunger 32, and the vibration direction (amplitude direction) of the diaphragm 17a is the tip surface. It is the direction which opposes. When the ball screw mechanism of the plunger drive unit 33 is driven, the fine vibration is mainly transmitted from the tip surface side of the head 32a of the plunger 32 to the coating liquid. Therefore, the vibration generator 17 vibrates the coating liquid with the direction toward the head 32a as a vibration direction, so that the fine vibration caused by the ball screw mechanism can be canceled efficiently.
Further, since the vibration generator 17 is attached to the cylinder 31 in a fixed state, it is easy to install a cable for transmitting a signal to the vibration generator 17.

[Second Embodiment]
In FIG. 3, the case where the vibration generator 17 is provided in the cylinder 31 of the pump main body 1 has been described. However, as shown in FIG. 5, the vibration generator 17 may be installed on the plunger 32. In this case, a recess 32c is formed on the tip side of the head 32a, and the vibration generator 17 is installed in the recess 32c. A diaphragm 17a included in the vibration generator 17 is disposed on the opening side of the recess 32c. A flexible membrane member 18 made of rubber or the like is provided so as to be in close contact with the diaphragm 17a and to close the recess 32c. Alternatively, as shown by a two-dot chain line in FIG. 5, the membrane member 18 may be omitted and the membrane-like sealing member 33 may be used.
As described above, when the vibration plate 17a is vibrated, vibration can be directly applied to the coating liquid in the coating liquid chamber a through the film member 18 (film-shaped sealing member 33). In addition, compared with 1st embodiment of FIG. 2, although the installation structure of the vibration generator 17 in the pump main body 1 differs, it is the same about other structures.

[Third embodiment]
FIG. 6 is a schematic configuration diagram showing another embodiment of the coating apparatus. Compared with the first embodiment of FIG. 2, the water stop structure of the coating liquid in the pump body 1 is different, but the other configurations are the same. That is, in the embodiment of FIG. 2, the coating liquid is sealed by the film-shaped sealing member 34, but in the embodiment of FIG. 6, an O-ring 36 is used instead of the film-shaped sealing member 34. That is, an O-ring 36 is provided between the cylinder 31 and the head 32 a of the plunger 32.

  In the case of this third embodiment, when the head 32a is moved by driving the plunger drive section 33, slip occurs at the sliding portion of the O-ring 36, and when this slip occurs intermittently, the coating liquid in the coating liquid chamber a May cause pulsation. Even in this case, similarly to the first embodiment, the pressure sensor 19 can detect the pulsation (pressure fluctuation) of the coating liquid and the actuator 7 can cancel the pulsation. In addition, when the film-shaped sealing member 34 is employ | adopted as a sealing member like 1st embodiment, the said pulsation by the O-ring 36 does not generate | occur | produce. For this reason, it is more preferable to employ the film-like sealing member 34 as the sealing member from the viewpoint of suppressing the uneven application of the substrate 12.

[Fourth embodiment]
FIG. 7 is a schematic configuration diagram showing still another embodiment of the coating apparatus. Compared with the first embodiment of FIG. 2, the configuration of the pump device is different, but the other configurations are the same. The pump body 41 of the pump device in the embodiment of FIG. 7 has a pump case 42, which is composed of a coating liquid chamber a for storing the coating liquid and an incompressible fluid by a flexible partition film 44. It is divided into an indirect liquid chamber c for storing a certain indirect liquid. The partition film 44 is, for example, a resin tube-like member provided in the pump case 42, and the inner area is the coating liquid chamber a and the outer area is the indirect liquid chamber c. A discharge port 45 a connected to the nozzle 10 is provided at one end of the coating liquid chamber a, and a suction port 45 b connected to the tank 2 is provided at the other end.

The pump body 41 further includes a cylinder 46 and a plunger 47. The cylinder 46 is connected to the pump case 42, and the plunger 47 can move within the cylinder 46. The area on the front side (right side) in the cylinder 46 is continuous with the area on the outside of the pump case 42, and the indirect liquid chamber c is defined by the area on the front side of the cylinder 46 and the area on the outside of the pump case 42. Is configured.
The plunger drive unit 48 includes a servo motor 48a and a ball screw mechanism (not shown), and the operation of the plunger 47 is controlled when the servo motor 48a is controlled by the control device 26.
When the plunger drive unit 48 is driven, the indirect liquid in the indirect liquid chamber c can be pressurized by moving the plunger 47 to the pump case 42 side. When the indirect liquid is pressurized, the partition film 44 is deformed (two-dot chain line in FIG. 7), and the volume of the coating liquid chamber a is reduced. Thus, by reducing the volume of the coating liquid chamber a, the coating liquid in the coating liquid chamber a can be sent out to the nozzle 10.
Further, the plunger 47 and the cylinder 46 shown in FIG. 7 are sealed to prevent the indirect liquid in the indirect liquid chamber c from leaking into the space chamber (negative pressure chamber) d, similarly to the pump body 1 shown in FIG. As a structure, a film-like sealing member 49 is provided.

According to the above configuration, when the plunger driving unit 48 is driven, for example, periodic fine vibration is generated in the ball screw portion, and this fine vibration is transferred to the indirect liquid in the indirect liquid chamber c through the plunger 47 and the cylinder 46. It is transmitted. This slight vibration appears as pressure fluctuation in the indirect liquid, and is transmitted to the coating liquid in the coating liquid chamber a via the partition film 44, and pressure fluctuation is likely to occur in the coating liquid.
Therefore, the pump device includes an actuator 40, and this actuator 40 is driven by the plunger drive unit 48, and thus is transmitted through the indirect liquid in the indirect liquid chamber c and the partition wall film 44, so As an operation for suppressing the pressure fluctuation to be generated in the liquid, an operation for canceling the pressure fluctuation in the indirect liquid can be performed in the pump body 41. In the fourth embodiment, the example using the film-shaped sealing member 49 has been described. However, a contact seal such as an O-ring may be used instead of the film-shaped sealing member 49.

  Similar to the first embodiment, the actuator 40 includes a vibration generator 40a made of a voice coil linear motor, a piezoelectric vibrator, or the like. The vibration generator 40a is installed in the indirect liquid chamber c so that the indirect liquid can be vibrated. More specifically, the vibration generator 40 a is attached to the pump case 42. Although not shown, the vibration generator 40a may be attached to the cylinder 46. The vibration generator 40a gives the indirect liquid in the indirect liquid chamber c a vibration that cancels the pressure fluctuation generated in the indirect liquid. Thereby, pressure fluctuations (pulsations) that are about to occur in the coating liquid in the coating liquid chamber a can be indirectly suppressed.

  In order to control the operation of the vibration generator 40a, a pressure sensor 37 that detects the pressure of the indirect liquid in the indirect liquid chamber c and a phase inversion that generates a signal for causing the vibration generator 40a to perform a predetermined operation. And a portion 38. The detection surface of the pressure sensor 37 is exposed to the indirect liquid chamber c. The phase inverting unit 38 is configured by a phase inverting circuit as in the embodiment of FIG. 2, and the phase inverting unit 38 performs an operation of giving the pressure fluctuation to the indirect liquid in a phase opposite to the pressure fluctuation detected by the pressure sensor 37. The vibration generator 40a is configured to generate a signal for execution. The signal generated by the phase inverting unit 38 is amplified by the amplifier 21 and transmitted to the vibration generator 40a.

  According to the above configuration, pressure fluctuation occurs in the indirect liquid in the indirect liquid chamber c by driving the plunger driving unit 48. Therefore, when the pressure sensor 37 detects a change in the pressure of the indirect liquid in the indirect liquid chamber c, the phase inversion unit 38 performs an operation of giving the indirect liquid a pressure fluctuation having a phase opposite to the pressure fluctuation. A signal to be executed by 40a is generated. And if the vibration generator 40a operate | moves based on this signal, the pressure fluctuation which arises in the indirect liquid in the indirect liquid chamber c can be canceled in the indirect liquid chamber c. That is, the pressure fluctuation which is transmitted to the coating liquid in the coating liquid chamber a due to the pressure fluctuation of the indirect liquid can be suppressed in advance in the indirect liquid chamber c. Therefore, the pulsation due to the drive of the plunger drive unit 48 does not occur in the coating liquid delivered from the pump body 41.

According to each of the embodiments described above, even if the pressure fluctuation is caused in the coating liquid in the pump body 1 (41) due to the operation of the pump device, the actuator 7 (40) performs an operation of suppressing the pressure fluctuation. Therefore, it is possible to prevent pulsation from occurring in the coating liquid sent to the nozzle 10. For this reason, the discharge pressure of the coating liquid in the nozzle 10 becomes constant, the film thickness of the coating liquid discharged onto the substrate 12 becomes uniform, and the occurrence of uneven coating on the substrate 12 can be prevented.
Further, as shown in FIG. 8, conventionally, it is necessary to install the pressurizer 56 in the middle of the flow path of the coating liquid, and it is necessary to add a pipe accordingly, and the configuration becomes complicated. According to each embodiment, such a pipe is unnecessary and the configuration is simple. Further, the addition of the pressurizer 56 and the like as in the prior art generates a stagnant portion of the coating liquid. In the present invention, this can be prevented. For example, when the coating liquid is replaced, the replaceability is improved. Maintenance performance is also high.

Further, as shown in FIG. 8, in the prior art, many delay elements and nonlinear elements are involved in the control for eliminating the pressure fluctuation of the coating liquid generated by driving the pump 53, and the control system becomes complicated. That is, the transfer function becomes complicated. Furthermore, fluctuations in the piping (tube) between the pressure sensor 54 and the pressurizer 56 become disturbances and control becomes unstable.
However, according to each of the embodiments of the present invention, the actuator 7 (40) performs the operation of canceling the pressure fluctuation in the pump body 1 (41) serving as a generation part (generation source) of the pressure fluctuation. There is no intermediate pipe as in the prior art, there is no disturbance due to the pipe, the control system of the actuator 7 (40) is simplified, and the control can be stabilized. Furthermore, the gain of this control can be easily adjusted. As a result, it is possible to improve the quality of the coated substrate produced by applying the coating solution to the substrate 12.

Further, the present invention is not limited to the illustrated form, and other forms may be employed within the scope of the present invention. For example, in the above-described embodiment, the case where the base part 22 moves with respect to the stage 14 in the fixed state has been described, but the stage 14 may move with respect to the base part 22 in the fixed state.
In each of the above embodiments, when the pressure sensor 17 (37) detects a change in pressure, the phase inversion unit 20 (38) generates an anti-phase wave signal having a phase opposite to that of the change, via the amplifier 21. The signal is input to the actuator 7 (40), and the actuator 7 (40) operates. For this reason, the response of the actuator 7 (40) to the detection by the pressure sensor 17 (37) is good, and the fluctuation of the pressure can be offset. However, the phase inversion unit 20 (38) and the actuator 7 (40) Although not shown, a timing generation unit may be provided between them. The timing generation unit can acquire the phase of the pressure fluctuation detected by the pressure sensor 17 (37), and the anti-phase wave signal generated by the phase inversion unit 20 (38) can be used as the coating liquid (indirect liquid). ) In synchronism with the phase of the pressure fluctuation occurring in the actuator 7 (40). The timing generation unit can be configured as a functional unit of the control device 26.
Moreover, although the said embodiment demonstrated the coating device used for manufacture of a color filter, it is applicable also to the coating device used for manufacture of a flat panel display, an organic battery, etc. containing organic EL.

DESCRIPTION OF SYMBOLS 1,41: Pump main body 7,40: Actuator, 10: Nozzle, 12: Board | substrate, 14: Stage, 17, 40a: Vibration generator (vibration generation part) 19, 37: Pressure sensor (sensor), 20, 38: Phase inversion part, 31e, 45a: Discharge port, 33: Plunger drive part (drive part), 42: Pump case, 44: Partition wall film, a: Coating liquid chamber, c: Indirect liquid chamber

Claims (3)

A pump device for delivering a coating liquid to the nozzle of a coating apparatus that discharges a coating liquid from a nozzle to form a coating film,
A pump body having a coating solution chamber for storing the coating solution and a discharge port for discharging the coating solution in the coating solution chamber;
A drive unit that is driven to discharge the coating liquid from the discharge port;
An actuator that performs an operation in the pump body to suppress pressure fluctuations that are about to occur in the coating liquid in the coating liquid chamber by driving the driving unit;
Equipped with a,
The pump body has a pump case that is partitioned into a coating liquid chamber for storing the coating liquid and an indirect liquid chamber for storing an indirect liquid by a flexible partition film, and the indirect liquid is driven when the driving unit is driven. The volume of the coating liquid chamber is reduced by deforming the partition film by pressurizing
The pump device according to claim 1, wherein the actuator includes a vibration generating unit that applies vibration to the indirect liquid as an operation for suppressing the pressure fluctuation . A sensor for detecting the pressure of the indirect liquid;
A phase reversing unit that generates a signal for causing the vibration generating unit to perform an operation of giving the indirect liquid a vibration having a phase opposite to the pressure fluctuation detected by the sensor;
The pump device according to claim 1, further comprising: A stage on which a substrate is placed;
A nozzle that relatively moves along the substrate and discharges the coating liquid onto the substrate;
A coating apparatus comprising: the pump device according to claim 1 or 2 that feeds a coating liquid to the nozzle.

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