TWI757407B - Method and apparatus for coating substrate - Google Patents

Abstract

[Purpose]

This invention provides for a method and apparatus for coating a substrate capable of easily obtaining a constant thickness of coating layer as much as possible in a period of a few seconds from a beginning of coating when the substrate is coated with the coating liquid in a manner that a discharge of the coating liquid from the nozzle starts simultaneously with a movement of the nozzle, thereby an applicable area in the substrate is not reduced.

[Means]

A method for coating a substrate gradually accelerates a moving speed (Vt ; Vt1, Vt2, Vt3) of a nozzle 3 for discharging a coating liquid (D) so that a quantity of coating liquid per unit area of the substrate 8 is constant, when the substrate is coated with the coating liquid in a manner that a discharge of the coating liquid from the nozzle starts simultaneously with a movement of the nozzle, thereby the constant thickness of the coating layer is obtained.

Description

Substrate coating method and substrate coating device

The present invention relates to the fact that, when the movement of the nozzle and the discharge of the coating liquid from the nozzle are simultaneously started, the thickness of the coating film during a period of several seconds from the start of the coating can be easily made constant as much as possible, so that the substrate can be A method for coating a substrate and a coating apparatus for a substrate using a substrate that does not reduce the area.

In a coating device such as a table coater that coats a coating liquid on a substrate made of glass, etc., although the coating liquid can be applied to a uniform coating film thickness (the tolerance of the film thickness distribution is 1 Units below microns) are applied to the entire substrate, but there is a time delay of several seconds from the start of the nozzle to discharge the coating liquid until the discharge flow rate of the coating liquid is constant, and the coating is applied to the range of the nozzle moved during this period. The thickness of the film is reduced and it cannot be used as a product, so it is removed from the substrate and discarded. Therefore, the method which does not reduce the utilization area of a board|substrate is requested|required, and patent documents 1 - 4 are known as a coating apparatus and a coating method for the countermeasure.

The subject of the "coating device for substrates" of Patent Document 1 is that the coating amount of the coating liquid on the surface of the substrate can be adjusted with high precision in real time, and the amount of coating liquid generated at the start of the coating and the end of the coating can be reduced. The film thickness non-uniform region, and the substrate coating apparatus includes a slit nozzle, a first camera, a second camera, a control unit, a pump, and a pressure regulating chamber. The control unit controls the supply amount of the coating liquid from the pump to the slit nozzle based on the comparison result of the bead shape imaged by the first camera and the reference shape. Moreover, the control part controls the air pressure on the upstream side of the slit nozzle using the pressure regulating chamber based on the comparison result of the distance measured from the image captured by the second camera and the reference distance.

The subject of "Method and Apparatus for Applying a Chemical Solution" in Patent Document 2 is that in the basic configuration of applying the chemical agent discharged from the slit to the surface of the substrate that is relatively moving, including the start of the application and the end of the application When the film thickness variation is suppressed as a whole, the chemical solution can be applied uniformly, and the nozzles of the first slit and the preceding second slit are arranged side by side in parallel with respect to the substrate that is relatively moving. When the chemical liquid is applied to the substrate, the chemical liquid is suppressed by controlling so that the chemical liquid is first ejected from the first slit and then the chemical liquid is ejected from the second slit when the coating is started. The uplift at the beginning of coating, and the in-plane film thickness on the substrate is uniformized.

The "coating apparatus and coating method" of Patent Document 3 includes: a coating liquid supply source that pressurizes the coating liquid and supplies it by extruding it toward the coating liquid supply system; and a nozzle that is connected to the coating liquid supply system. The coating liquid supply system is used to carry out the coating process; the syringe pump is installed in the coating liquid supply system, and the interior is filled with the coating liquid, and only when the coating process starts, the coating liquid is discharged and supplied to the The nozzle, on the other hand, suppresses the change of the pressure transmitted from the coating liquid supply source to the nozzle when the supply of the coating liquid to the nozzle is stopped; the on-off valve for filling the syringe pump is only used for supplying the coating liquid to the syringe pump and an on-off valve, which is closed when the coating process is started with the syringe pump, when the coating liquid is supplied to the syringe pump, and in response to stopping the coating of the syringe pump in order to supply the coating liquid to the nozzle The liquid supply is turned on.

In the "coating device" of Patent Document 4, the problem is that in a coating device using a die head, the area of insufficient film thickness that occurs at the start of coating is reduced, and the problem is that it has the ability to hold the substrate. The chuck table that is moved, the die for coating that coats the coating liquid on the substrate, and the coating apparatus of the piping and pump that are connected so as to supply the coating liquid to the die have the following structures : Install a back pressure valve in the piping close to the die head to maintain the desired pressure in the piping up to the pump, and apply appropriate pressure to the piping at any time, so that the discharge pressure can be rapidly increased when the pump starts to operate. It rises to the ground, and the desired discharge volume can be ensured in a short time.

[Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Publication No. 2010/106979

[Patent Document 2] Japanese Patent Laid-Open No. 11-179262

[Patent Document 3] Japanese Patent Laid-Open No. 2016-87601

[Patent Document 4] Japanese Patent Laid-Open No. 2004-50026

Patent Document 1 has the following problems: it is necessary to have a first camera that captures the shape of beads and a second camera that captures an image for air pressure control, and a control unit that performs complex processing such as image processing, so that the The equipment becomes larger and the cost becomes higher.

In Patent Document 2, the first and second slits are provided in the nozzle, and the chemical liquid is sequentially discharged from these slits to suppress the rise of the chemical liquid at the start of application. , the uneven thickness of the liquid film cannot be avoided.

Patent Document 3 only uses a syringe pump to supply the coating liquid to the nozzle at the start of the coating process, thereby precisely controlling the discharge amount at the start of coating, but the on-off valve that switches from the syringe pump to the coating liquid supply source. It is difficult to adjust the switching timing, and it is difficult to ensure a certain coating thickness from the start of coating.

In Patent Document 4, a back pressure valve is provided near the die to rapidly increase the discharge pressure of the die, but even with the above configuration, there is resistance at the moment when the coating liquid is extruded from the die, and the coating liquid is stabilized. It takes several seconds until the ground is discharged, and it is difficult to ensure a constant film thickness from the start of coating.

For the above-mentioned problem, although the experience value of the control mode such as the nozzle moving speed or discharge flow rate at the start of coating can be input to the flat-bed coater, the substrate can be tested for coating, and the film thickness can be measured. , and find the most appropriate control mode according to the measurement results, but it is difficult to obtain the best control mode by one trial coating, so the trial coating and film thickness measurement must be repeated many times. The accumulation of the coating liquid, the substrate for trial coating, and the loss of working time caused by the repeated operation is quite troublesome.

Furthermore, in the manufacturing process, in addition to performing trial coating every time the composition or viscosity of the coating liquid to be applied is changed, and when a new coating liquid is used, it is necessary to grope for it without any basis. The state is repeatedly tested. In addition, even if the coating liquid of the same composition is used, it will deteriorate over time, so the best coating mode obtained before can not be applied again after a few days, and the above-mentioned repeated operation must be performed again, so that the The coating operation requires considerable man-hours.

Therefore, there is a demand for an invention that can make the thickness of the coating film constant during the period from the start of coating until the discharge of the coating liquid is stabilized and coating can be performed with a constant coating film thickness, so that the usable area of the substrate is not reduced.

The present invention has been proposed in view of the above-mentioned conventional problems, and an object of the present invention is to provide a situation in which the movement of the nozzle and the discharge of the coating liquid from the nozzle are simultaneously started, so that the coating can be easily made for a period of several seconds from the start of the coating. The film thickness is fixed as much as possible, and the substrate coating method and the substrate coating device can not reduce the utilization area of the substrate.

The method for coating a substrate according to the present invention is characterized in that the movement of the nozzle for discharging the coating liquid and the discharging of the coating liquid from the nozzle are simultaneously started, and when the coating liquid is applied to the substrate, the moving speed of the nozzle is adjusted to Gradually increase the amount of the coating liquid per unit area of the substrate to be constant.

The substrate coating method of the present invention is characterized by using a measured pressure value corresponding to the discharge flow rate measured by a pressure sensor, and the pressure sensor measures the discharge flow rate of the coating liquid from the nozzle per unit time. The supply pressure of the relevant coating liquid is made so that the moving speed of the nozzle corresponds to the increase of the measured pressure value during the period from the start of the discharge of the coating liquid until the above-mentioned measured pressure value reaches the predetermined pressure value corresponding to the set discharge flow rate. And the growth rate.

The substrate coating method of the present invention is characterized by using a measured pressure value Pt corresponding to a discharge flow rate measured by a pressure sensor that measures the discharge of the coating liquid from the nozzle per unit time. The supply pressure of the coating liquid related to the flow rate is used when the nozzle is moved at the set moving speed Vc and the coating liquid is discharged at a predetermined pressure value Pc corresponding to the set discharge flow rate to apply the coating liquid to the substrate. The moving speed Vt of the nozzle relative to the measured pressure value Pt during the period from the start of the discharge of the coating liquid until the measured pressure value Pt reaches the predetermined pressure value Pc is calculated by the following formula: Pt: Vt=Pc: Vc ( Among them, 0≦Pt≦Pc)...(1).

The method for coating a substrate according to the present invention is characterized in that, in preparation for applying the coating liquid to the substrate, the coating liquid is discharged from the nozzle and the pressure sensor is used to measure the supply pressure during the period, and then The coating liquid is applied to the substrate by moving the nozzle at the moving speed Vt calculated from the measured pressure value Pt corresponding to the discharge flow rate output from the pressure sensor using the formula (1).

The method for coating a substrate of the present invention is characterized in that the substrate is moved instead of moving the nozzle.

The apparatus for coating a substrate according to the present invention, which is used in the coating method for the substrate, is characterized by comprising: the nozzle for discharging and coating the coating liquid on the substrate while moving; the pressure sensor , which measures the above-mentioned supply pressure of the coating liquid related to the discharge flow rate of the coating liquid per unit time from the nozzle and outputs the above-mentioned measured pressure value corresponding to the discharge flow rate; and an arithmetic controller, which uses the above-mentioned formula (1) and Based on the measured pressure value input from the pressure sensor, the moving speed of the nozzle is calculated and output to the nozzle.

In the substrate coating method and substrate coating apparatus of the present invention, when the movement of the nozzle and the discharge of the coating liquid from the nozzle are simultaneously started, the configuration can be easily and simply made several seconds from the start of coating. During the period, the thickness of the coating film is as constant as possible, so that the utilization area of the substrate will not be reduced.

1‧‧‧Coating device

2‧‧‧Abutment

3‧‧‧Nozzle

3a‧‧‧chamber

4‧‧‧Supply piping

5‧‧‧Slot

6‧‧‧Three-way valve

7‧‧‧Syringe pump

7a‧‧‧motor

7b‧‧‧Piston

7c‧‧‧Cylinder

8‧‧‧Substrate

9‧‧‧Pressure sensor

10‧‧‧Calculation Controller

11‧‧‧Coating liquid recovery container

12‧‧‧Airtight groove

13‧‧‧On-off valve

14‧‧‧Air inlet piping

15‧‧‧On-off valve

D‧‧‧Coating liquid

Pc‧‧‧The preset pressure value corresponding to the set discharge flow rate

Pt‧‧‧Measured pressure value corresponding to discharge flow

P1‧‧‧Port 1

P2‧‧‧Port 2

P3‧‧‧Port 3

Vc‧‧‧Set movement speed

Vt‧‧‧movement speed

Vt1‧‧‧movement speed

Vt2‧‧‧movement speed

Vt3‧‧‧movement speed

FIG. 1 is a schematic diagram showing the measurement state of the supply pressure of the coating liquid acting on the nozzle, and the coating method of the substrate and the coating apparatus of the substrate according to the present invention.

FIG. 2 is a graph illustrating the relationship between the supply pressure of the coating liquid and the moving speed of the nozzle obtained by the measurement of FIG. 1 .

FIG. 3 is a schematic diagram showing a state in which a coating liquid is applied to a substrate using the method for coating the substrate and the coating apparatus shown in FIG. 1 .

FIG. 4 is a schematic view showing a modification of the coating apparatus for the substrate shown in FIGS. 1 and 3 and applying a coating liquid to the substrate.

Hereinafter, the preferred embodiments of the substrate coating method and the substrate coating apparatus of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a schematic diagram showing the state of measurement of the supply pressure of the coating liquid applied to the nozzle for the coating method of the substrate and the coating apparatus for the substrate according to the present embodiment, and FIG. 2 illustrates the coating obtained by the measurement in FIG. 1 . Fig. 3 is a graph showing the relationship between the supply pressure of the liquid distribution and the moving speed of the nozzle, and Fig. 3 is a schematic diagram showing a situation in which the coating liquid is applied to the substrate using the substrate coating method and the coating apparatus shown in Fig. 1 .

As shown in FIG. 1 , a substrate coating apparatus 1 according to the present embodiment includes a nozzle 3 that is movably installed above a base 2 to discharge a coating liquid D, and a supply pipe 4 that is connected to The nozzle 3 is for supplying the coating liquid D to the nozzle 3;

In the present embodiment, the supply pipe 4 is provided with a three-way valve 6, the first port P1 is connected to the tank 5 side, and the third port P3 is connected to the nozzle 3 side. A syringe pump 7 is connected to the second port P2 of the three-way valve 6 . The syringe pump 7 sucks the coating liquid D stored in the tank 5 , and controls the flow rate of the sucked coating liquid D to send it toward the nozzle 3 .

When the three-way valve 6 sucks the coating liquid D by the syringe pump 7, the first port P1 and the second port P2 communicate with each other in a state where the third port P3 is closed. When the three-way valve 6 sends out the coating liquid D from the syringe pump 7, the second port P2 and the third port P3 communicate with each other in a state where the first port P1 is closed. Thereby, the coating liquid D in the tank 5 is supplied to the nozzle 3 by the operation of the syringe pump 7 .

Furthermore, in addition to using one three-way valve 6, this action can also be realized by combining two two-way valves so that the same function can be obtained.

The syringe pump 7 has a piston 7b driven with a precise stroke by a motor 7a, and when the coating liquid D is sucked, the coating liquid D is filled in the cylinder 7c without gaps, and the coating liquid D is fed out. In the case of liquid D, the coating liquid D is supplied to the nozzle 3 with high supply amount control accuracy. The coating liquid D may be any kind of high viscosity.

In addition, as shown in FIG. 3 , when the coating liquid D is applied to the substrate 8, the substrate 8 is set on the upper surface of the base 2, the nozzle 3 is relatively moved with respect to the substrate 8, and the coating material discharged from the nozzle 3 is applied. The liquid D is applied to the substrate 8 .

When the movement of the nozzle 3 and the discharge of the coating liquid D from the nozzle 3 are simultaneously started and the coating liquid D discharged from the nozzle 3 is applied to the substrate 8, as described above, from the start of the coating to During the period until the discharge of the coating liquid D is stable (initial stage), it is difficult to obtain a constant coating film thickness, and after that, when the discharge of the coating liquid D is stable (stable stage), the coating can be applied with a constant coating film thickness.

In detail, in the stable stage, the coating liquid D is supplied to the nozzle 3 at a constant supply pressure, whereby the coating liquid D is discharged from the nozzle 3 at a constant flow rate. Therefore, if the nozzle 3 is moved at a constant speed Moving, the amount of the coating liquid per unit area of the substrate 8 becomes constant, and as a result, a constant coating film thickness can be obtained.

On the other hand, even if the supply pressure for supplying the coating liquid D to the nozzle 3 is changed (gradually increased) in the initial stage, the coating liquid D discharged from the nozzle 3 cannot reach a constant flow rate, and the nozzle 3 is moved simultaneously. , so it is difficult to obtain a certain film thickness.

The coating method and coating apparatus for the substrate of the present embodiment are set so as to obtain a constant coating film thickness as much as possible in the initial stage.

In the case where the coating liquid D is applied to the substrate 8 with a certain coating film thickness as described above, the amount of the coating liquid per unit area of the substrate 8 must be constant. The amount of the coating liquid toward the substrate 8 can be controlled and managed as long as the discharge flow rate of the coating liquid D from the nozzle 3 is controlled and managed. .

The inventors of the present application discovered and confirmed that even with the existing equipment, the discharge flow rate of the coating liquid D from the nozzle 3 , specifically, the discharge flow rate of the coating liquid D from the nozzle 3 per unit time is different from the coating liquid D acting on the nozzle 3 . The supply pressure is sufficiently correlated, and the present invention has been completed by focusing on controlling and managing the discharge flow rate of the coating liquid D from the nozzle 3 by measuring the supply pressure with the pressure sensor 9 described later.

When the coating liquid D is applied to the substrate 8, there are cases where the discharge flow rate of the coating liquid D from the nozzle 3 is set (set discharge flow rate) relative to a stable stage where a certain coating film thickness can be obtained. (The predetermined pressure value Pc (upper limit value) of the supply pressure corresponding to the set discharge flow rate is determined), and the set moving speed Vc (upper limit value) is set as the moving speed of the nozzle 3 (the following first embodiment) Example): Only the supply pressure considers the predetermined pressure value Pc (upper limit value) corresponding to the set discharge flow rate, and the nozzle 3 is moved at the moving speed when the predetermined pressure value Pc corresponding to the set discharge flow rate is reached as a constant moving speed (The second embodiment described below); and regardless of the predetermined pressure value Pc corresponding to the set discharge flow rate, the nozzle 3 takes the constant supply pressure when the supply pressure becomes constant, and the moving speed when the constant supply pressure becomes constant as the constant supply pressure. The case where the moving speed is shifted (the third embodiment described below).

"First Embodiment"

The first embodiment is a case where the set discharge flow rate and the set moving speed Vc are respectively set as the discharge flow rate of the coating liquid D and the moving speed of the nozzle 3, respectively. There is a predetermined pressure value Pc corresponding to the set discharge flow rate corresponding to the set discharge flow rate, and the predetermined pressure value Pc corresponding to the set discharge flow rate is determined by the pressure sensor 9 as the measured pressure value Pt corresponding to the discharge flow rate. Measurement.

The coating method and coating apparatus for a substrate according to the present embodiment are provided with a pressure sensor 9 (see FIG. 1 ) for measuring the supply pressure of the coating liquid D, and an arithmetic controller 10 (see FIG. 1 ) such as a notebook computer. 3), which inputs the measured pressure value Pt corresponding to the discharge flow rate measured by the pressure sensor 9, calculates the moving speed Vt of the nozzle 3, and outputs the calculated moving speed Vt to the nozzle 3 for speed control.

As shown in FIG. 1 , the pressure sensor 9 measures the supply pressure of the coating liquid D acting on the nozzle 3 that discharges the coating liquid D, and directs the measured pressure value Pt corresponding to the measured discharge flow rate to the calculation controller 10 output. That is, the pressure sensor 9 measures the pressure generated in the chamber 3a inside the nozzle 3 or the pressure generated in the supply pipe 4 in order to discharge the coating liquid D from the nozzle 3 as the supply pressure.

Therefore, the pressure sensor 9 is provided in the nozzle 3 .

The operation of measuring the supply pressure with the pressure sensor 9 to obtain the measured pressure value Pt corresponding to the discharge flow rate is performed during the coating preparation before the coating liquid D is applied to the substrate 8 . When preparing for coating, place a coating liquid recovery container 11 such as a receiving tray on the base 2 directly below the nozzle 3, or move the nozzle 3 to a position away from the base 2 and in a state without a substrate, by The syringe pump 7 sends the coating liquid D toward the nozzle 3, and the pressure sensor 9 measures the change until the supply pressure becomes a predetermined pressure value Pc corresponding to the set discharge flow rate.

The measured pressure value Pt corresponding to the discharge flow rate obtained by the pressure sensor 9 becomes the predetermined pressure value corresponding to the set discharge flow rate from the start of the syringe pump 7 (corresponding to the time point when the movement of the nozzle 3 starts) until the supply pressure. Up to Pc, as time elapses, a plurality of them are sequentially output in millisecond units, for example. Here, the measured pressure value Pt corresponding to the discharge flow rate refers to the measured pressure value t seconds after the start of discharge of the coating liquid D. The measured pressure value Pt corresponding to the discharge flow rate is input to the calculation controller 10 from the pressure sensor 9 .

The calculation controller 10 uses the measured pressure values Pt corresponding to the plurality of discharge flow rates over time, and performs calculation by the following formula (1) to calculate the plurality of moving speeds Vt of the nozzle 3 over time, and calculates These are stored. And next, the board|substrate 8 is mounted on the base 2, and the movement of the nozzle 3 is controlled by this memorized movement speed Vt. Here, the moving speed Vt corresponds to the measured pressure values Pt corresponding to the plurality of discharge flow rates, respectively, and is the moving speed t seconds after the start of discharge of the coating liquid D.

In the stabilization stage, when the substrate 8 is coated with the predetermined pressure value Pc (constant) corresponding to the set discharge flow rate and the set moving speed Vc (constant), the amount of coating liquid per unit area of the substrate 8 is determined by the set moving speed The relationship of Vc with respect to the predetermined pressure value Pc corresponding to the set discharge flow rate is prescribed|regulated. That is, the larger (faster) the value of the set moving speed Vc relative to the predetermined pressure value Pc corresponding to the set discharge flow rate is, the more the amount of the coating liquid per unit area of the substrate 8 is reduced, and the thinner the coating film is, on the contrary. Specifically, the smaller (slower) the value of the set moving speed Vc is, the larger the amount of the coating liquid is, and the thicker the coating film thickness is. In the initial stage, the relationship is also the same.

Therefore, for the relationship between the moving speed Vt in the initial stage and the measured pressure value Pt corresponding to the discharge flow rate, and the relationship between the set moving speed Vc in the stable stage and the predetermined pressure value Pc corresponding to the set discharge flow rate, the following equations can be applied (1).

Pt: Vt=Pc: Vc (wherein, 0≦Pt≦Pc)...(1)

If the formula (1) is arranged with the moving speed Vt of the nozzle 3 in the initial stage, it becomes Vt=(Vc/Pc)×Pt...(2).

The meaning of the above formula (2) is: if the moving speed Vt in the initial stage is a constant ratio (Vc/Pc) to the measured pressure value Pt corresponding to the discharge flow rate, the amount of coating liquid per unit area of the substrate 8 becomes constant. , and the film thickness is kept constant. Then, using a plurality of measured pressure values Pt corresponding to the discharge flow rate measured by the pressure sensor 9 for several seconds in the initial stage and corresponding to the discharge flow rate, and calculating by formula (2), a plurality of moving speeds are calculated. Vt (represented by Vt1, Vt2, and Vt3 in FIGS. 2 and 3).

For example, when Pc=100kPa and Vc=25mm/s when the discharge flow rate Q is 100cc/min, when Pt=10kPa (Q=10cc/min) immediately after the coating liquid is discharged from the nozzle 3 in the initial stage The moving speed Vt was calculated to be 2.5 mm/s, and the moving speed Vt when Pt=80 kPa (Q=80 cc/min) was calculated to be 20 mm/s.

When using the arithmetic controller 10 and according to a plurality of measured pressure values Pt corresponding to the discharge flow rate that can be obtained at the time of preparation, the function f(Pt) of the pressure change can be obtained as the test formula, as shown in Figure 2. As shown, it is also possible to multiply the function f(Pt) by setting the ratio (Vc/Pc) of the predetermined pressure value Pc to the set moving speed Vc as a multiplying factor to obtain the speed change of the moving nozzle 3 function f(Vt).

In the case of the first embodiment, the above initial stage can be rephrased as “from the start of the discharge of the coating liquid D (the start of the movement of the nozzle 3) until the measured pressure value Pt corresponding to the discharge flow rate reaches a predetermined value corresponding to the set discharge flow rate. The period of several seconds until the pressure value Pc". Then, after finishing the preparation, starting from the actual application to the substrate 8, in the initial stage, the value from "0" to the measured pressure value Pt corresponding to the discharge flow rate is based on the moving speed Vt calculated by the calculation controller 10. When ascending, the moving speed of the nozzle 3 is increased from the speed "0", and as long as the amount of the coating liquid per unit area of the substrate 8 is constant, the thickness of the coating film will be constant.

After the initial stage, when the measured pressure value Pt corresponding to the discharge flow rate becomes the predetermined pressure value Pc corresponding to the set discharge flow rate (stable stage), the nozzle 3 is moved at the set moving speed Vc.

According to the substrate coating method and coating apparatus of the first embodiment, when the movement of the nozzle 3 and the discharge of the coating liquid D from the nozzle 3 are simultaneously started to apply the coating liquid D to the substrate 8, use The pressure sensor 9 is used to measure the change of the supply pressure of the coating liquid D in the initial stage, and to the measured pressure value Pt corresponding to the measured discharge flow rate, the following formula (1) Pt: Vt=Pc: Vc ( Among them, 0≦Pt≦Pc)...(1)

Since the moving speed Vt of the nozzle 3 is calculated by the arithmetic controller 10, and the calculated moving speed Vt is output to the nozzle 3 to control the coating at the initial stage, it is possible to coat the film during a period of several seconds from the start of coating. The thickness is as constant as possible. Thereby, the utilization area of the board|substrate 8 can be prevented from being reduced.

In addition, in preparation for coating the substrate 8 with the coating liquid D, the coating apparatus 1 having the above-described configuration is used to perform the coating method in the above-described sequence only once, and the calculated moving speed Vt of the nozzle 3 can be used. To establish the optimal control mode for the movement of the nozzle 3 corresponding to the coating liquid D to be used, no trial coating is required, and the loss of the coating liquid for trial coating, the substrate for trial coating, and the operation time can be eliminated. The accumulation makes it possible to start the coating operation easily and quickly without labor.

In the substrate coating method and coating apparatus of the first embodiment, it is only necessary to add a pressure sensor 9 and an arithmetic controller 10, and it is possible to use a plurality of cameras or perform image processing as in Patent Document 1. In the case of the control section, it is constructed with simple equipment and at low cost.

In addition, since the first embodiment uses the general moving speed control of the nozzle 3, the configuration of the nozzle 3 is simple compared to the configuration and method of discharging the chemical liquid from two slits in two stages as in Patent Document 2 Furthermore, the discharge control can also be facilitated.

In addition, since the first embodiment performs coating only by controlling the moving speed of the nozzle 3, without the control of the supply amount of the coating liquid D by the syringe pump 7, it can be compared with those in Patent Document 3 or Patent Document 7. 4. In the case of controlling the supply of the coating liquid, the thickness of the coating film can be easily and precisely made constant.

"Second Embodiment"

In the second embodiment, the moving speed of the nozzle 3 is not set, but only a predetermined pressure value Pc corresponding to the set discharge flow rate is set, and the moving speed of the nozzle 3 when the predetermined pressure value Pc corresponding to the set discharge flow rate is set as the fixed moving speed while being moved.

In this case, from the start of the syringe pump 7 (corresponding to the movement start time point of the nozzle 3) to the measured pressure value Pt corresponding to the measured discharge flow rate, the pressure sensor 9 becomes the predetermined pressure corresponding to the set discharge flow rate. The measurement was performed until the value Pc, and this time was used for coating control.

Then, in the initial stage, the moving speed of the nozzle 3 is increased from the speed "0" in accordance with the increase of the measured pressure value Pt corresponding to the discharge flow rate from the value of "0" to the predetermined pressure value Pc corresponding to the set discharge flow rate. Therefore, the amount of the coating liquid per unit area of the substrate 8 is made constant. Thereby, the coating film thickness in the initial stage can be made as constant as possible. After the initial stage, in the stable stage when the measured pressure value Pt corresponding to the discharge flow rate becomes the predetermined pressure value Pc corresponding to the set discharge flow rate, the nozzle 3 is moved at a constant speed when the measured pressure value Pt corresponding to the set discharge flow rate becomes the predetermined pressure value Pc corresponding to the set discharge flow rate. move.

"Third Embodiment"

In the third embodiment, it is not necessary to set the moving speed of the nozzle 3 and the predetermined pressure value Pc corresponding to the set discharge flow rate, and the coating operation in the stable stage uses a constant supply pressure when the supply pressure becomes constant, and the nozzle 3 achieves a constant supply. The movement speed under pressure is moved as a fixed movement speed (at the stable stage).

As described in FIG. 4 to be described later, the above situation corresponds to a situation in which the airtight groove 12 is used instead of the syringe pump 7, and the flow rate is determined only by the supply pressure of the coating liquid.

In the third embodiment, the moving speed of the nozzle 3 is gradually increased from the speed "0" at the start time point, and when the supply pressure becomes constant, the amount of coating liquid per unit area of the substrate 8 becomes constant, And the coating film thickness becomes constant.

As described above, in "a period of about several seconds (initial stage) from the start of the discharge of the coating liquid D until the discharge amount of the coating liquid D from the nozzle 3 becomes constant (the supply pressure becomes constant)", due to the The amount of the coating liquid D is small due to the viscosity of the coating liquid D around the discharge portion of the nozzle 3, the resistance of the flow path, and other factors. Therefore, the nozzle 3 is moved slowly corresponding to the small amount. , and the movement of the nozzle 3 is gradually accelerated in accordance with the gradual increase in the amount of the coating liquid D. The above situation is represented by Vt1<Vt2<Vt3 in FIGS. 2 and 3 .

Thereby, the amount of the coating liquid per unit area of the substrate 8 becomes constant, and the thickness of the coating film becomes constant. As long as the supply pressure becomes constant after the initial stage and the discharge amount of the coating liquid D from the nozzle 3 becomes constant, the nozzle 3 is moved at a constant moving speed when the discharge amount (supply pressure) becomes constant.

Even in the second and third embodiments described above, the same functions and effects as those of the first embodiment can be obtained.

FIG. 4 is a schematic view showing a modification of the coating apparatus for the substrate shown in FIGS. 1 and 3 , and a state in which coating liquid D is applied to the substrate 8 .

In the above-described embodiment, the case where the three-way valve 6 is used and the coating liquid D is sucked from the tank 5 by the syringe pump 7 and sent out to the nozzle 3 has been described. 3. The airtight tank 12 in which the coating liquid D is stored is connected via the supply piping 4 provided with the on-off valve 15 . An air introduction pipe 14 for pressurization is connected to the airtight groove 12 via an on-off valve 13 . Then, the on-off valve 13 is opened, the inside of the airtight groove 12 is pressurized with a certain pressure by the pressurizing air introduced from the air introduction pipe 14, and the on-off valve 15 is opened, whereby the coating liquid D is supplied to the Nozzle 3, and from the nozzle 3 is spit out.

The pressure sensor 9 is provided in the nozzle 3 or the supply pipe 4 as in the above-described embodiment. It goes without saying that the same functions and effects as those of the above-described embodiment can be exhibited even in the above-described modified example.

In addition, in the above-mentioned embodiment, although the case where the nozzle 3 is relatively moved with respect to the substrate 8 provided on the base 2 has been described, it is not limited to this, and the substrate 8 may be The base 2 moves relatively with respect to the nozzles 3 which are arranged in a certain manner. In this case, the moving speed of the substrate 8 placed on the base 2 may be controlled similarly to the description of the moving speed of the nozzle 3 above.

1‧‧‧Coating device

2‧‧‧Abutment

3‧‧‧Nozzle

4‧‧‧Supply piping

5‧‧‧Slot

6‧‧‧Three-way valve

7‧‧‧Syringe pump

7a‧‧‧motor

7b‧‧‧Piston

7c‧‧‧Cylinder

8‧‧‧Substrate

9‧‧‧Pressure sensor

10‧‧‧Calculation Controller

D‧‧‧Coating liquid

Vc‧‧‧Set movement speed

Vt1‧‧‧movement speed

Vt2‧‧‧movement speed

Vt3‧‧‧movement speed

Claims (8)

A method for coating a substrate, characterized in that the movement of a nozzle for discharging a coating liquid and the discharging of the coating liquid from the nozzle are simultaneously started, and when the coating liquid is coated on a substrate, a pressure value is used to measure the pressure. The pressure value is measured by a pressure sensor installed at the nozzle to measure the supply pressure of the coating liquid acting on the nozzle, and corresponds to the discharge flow rate of the coating liquid from the nozzle per unit time. During the period from the start of discharge until the measured pressure value reaches a predetermined pressure value corresponding to the set discharge flow rate, the moving speed of the nozzle is gradually increased in response to the increase of the measured pressure value, so that the coating per unit area of the substrate is increased. The amount of liquid cloth becomes constant. A method for coating a substrate, characterized in that the movement of a nozzle for discharging a coating liquid and the discharging of the coating liquid from the nozzle are simultaneously started, and the measured pressure value Pt is used when the coating liquid is coated on the substrate. The measured pressure value Pt is measured by a pressure sensor installed in the nozzle to measure the supply pressure of the coating liquid acting on the nozzle and corresponds to the discharge flow rate of the coating liquid per unit time from the nozzle. When moving at the set moving speed Vc and discharging the coating liquid at a predetermined pressure value Pc corresponding to the set discharge flow rate to apply the coating liquid to the substrate, from the start of the discharge of the coating liquid until the measured pressure value Pt reaches the During the period up to the predetermined pressure value Pc, the moving speed Vt of the nozzle relative to the measured pressure value Pt is calculated by the following formula so that the amount of coating liquid per unit area of the substrate becomes constant, Pt: Vt= Pc: Vc (wherein, 0≦Pt≦Pc)…(1). The method for coating a substrate according to claim 2, wherein, in preparation before applying the coating liquid to the substrate, the coating liquid is discharged from the nozzle and the pressure sensor is used to measure the supply pressure during the period, Next, the coating liquid is applied to the substrate by moving the nozzle at the moving speed Vt calculated from the measured pressure value Pt corresponding to the discharge flow rate output from the pressure sensor using the above equation (1). A device for coating a substrate, which is used in the method for coating a substrate according to claim 2 or 3, characterized in that it is provided with the above-mentioned nozzle, which discharges and applies a coating liquid while moving. The above-mentioned substrate; the above-mentioned pressure sensor, which is arranged on the nozzle, and measures the supply pressure of the coating liquid acting on the nozzle, and outputs the measured value of the pressure sensor and the coating liquid per unit time from the The above-mentioned measured pressure value corresponding to the discharge flow rate of the nozzle; and a calculation controller, which uses the above-mentioned formula (1), according to the above-mentioned measured pressure value input from the pressure sensor, so that the coating liquid per unit area of the substrate is In such a way that the amount becomes constant, the moving speed of the nozzle is calculated and output to the nozzle. A method for coating a substrate, characterized in that the movement of the substrate and the discharge of the coating liquid from the nozzle are started simultaneously, and when the coating liquid is applied to the substrate, a measured pressure value is used, and the measured pressure value is set in a The pressure sensor that measures the supply pressure of the coating liquid acting on the nozzle corresponds to the discharge flow rate of the coating liquid per unit time from the nozzle, from the start of the discharge of the coating liquid to the measurement pressure During the period until the value reaches a predetermined pressure value corresponding to the set discharge flow rate, the moving speed of the substrate is gradually increased in accordance with the increase in the measured pressure value, and the amount of coating liquid per unit area of the substrate is made constant. A method for coating a substrate, characterized in that the movement of the substrate and the discharge of the coating liquid from the nozzle are simultaneously started, and when the coating liquid is applied to the substrate, a measured pressure value Pt is used, and the measured pressure value Pt is determined by The pressure sensor installed on the nozzle to measure the supply pressure of the coating liquid acting on the nozzle corresponds to the discharge flow rate of the coating liquid per unit time from the nozzle, and the substrate is moved at the set moving speed Vc In addition, when the coating liquid is discharged at the predetermined pressure value Pc corresponding to the set discharge flow rate and the coating liquid is applied to the substrate, from the start of the discharge of the coating liquid until the measured pressure value Pt reaches the predetermined pressure value Pc. During this period, the moving speed Vt of the substrate relative to the measured pressure value Pt is calculated by using the following formula in such a way that the amount of coating liquid per unit area of the substrate becomes constant, Pt:Vt=Pc:Vc (wherein, 0≦Pt≦Pc)…(1). The method for coating a substrate according to claim 6, wherein, in preparation for applying the coating liquid to the substrate, the coating liquid is discharged from the nozzle and the pressure sensor is used to measure the supply pressure during the period, Next, the substrate is moved at the moving speed Vt calculated from the measured pressure value Pt corresponding to the discharge flow rate output from the pressure sensor using the above equation (1), and the substrate is coated with coating liquid. An apparatus for coating a substrate, which is used in the method for coating a substrate according to claim 6 or 7, characterized by comprising: the nozzle for discharging a coating liquid to the moving substrate to apply the coating The cloth liquid is applied to the above-mentioned substrate; the above-mentioned pressure sensor, which is arranged on the nozzle, measures the supply pressure of the coating liquid acting on the nozzle, and outputs the value measured by the pressure sensor and the value per unit time painted The above-mentioned measured pressure value corresponding to the discharge flow rate of the cloth liquid from the nozzle; and the calculation controller, which uses the above-mentioned formula (1), according to the above-mentioned measured pressure value input from the pressure sensor, so as to make the substrate per unit area In such a manner that the amount of the coating liquid becomes constant, the moving speed of the substrate is calculated and output to the nozzle.

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