TWI750579B - Processing liquid supply device and control method of processing liquid supply device - Google Patents

Abstract

The present invention continuously supplies driving pulses to the stepping motor when the on-off valve is to be switched from the open state to the closed state. The valve body is moved toward the valve seat by the rotation of the stepper motor in response to the drive pulse. A detection pulse is output from the encoder in response to the rotation of the stepping motor. When the stepping motor stops rotating and the encoder does not output a predetermined number of continuous detection pulses, the supply of driving pulses is stopped. In this state, the switching of the on-off valve from the open state to the closed state is completed.

Description

Process liquid supply device and control method of process liquid supply device

The present invention relates to a processing liquid supply apparatus for supplying a processing liquid to a substrate and a control method of the processing liquid supply apparatus.

Conventionally, for FPD (Flat Panel Display) substrates, semiconductor substrates, optical disk substrates, magnetic disk substrates, etc. used in liquid crystal display devices and organic EL (Electro Luminescence) display devices, Various substrates such as magneto-optical disk substrates, photomask substrates, ceramic substrates, and solar cell substrates are subjected to various treatments, and a substrate processing apparatus is used.

In a substrate processing apparatus, for example, the processing liquid is supplied to the substrate from a processing liquid supply source through a pipe and a nozzle. An on-off valve is provided in the piping. The on-off valve switches between an open state in which the treatment liquid is ejected from the nozzle and a closed state in which the treatment liquid is not ejected from the nozzle.

Patent Document 1 discloses an on-off valve control device for controlling the above-described on-off valve. In this on-off valve control device, the position where the valve body of the on-off valve closes the flow path of the treatment liquid is set as the closed position. Based on the set closed position, the valve body is driven by a stepping motor.

There is a possibility that the appropriate position as the closed position may change due to wear of various members constituting the on-off valve. Therefore, the origin (reference) of the closed position is set periodically and automatically. When this setting is performed, first, a drive pulse for driving the valve body in the closing direction is supplied to the stepping motor. Next, after detecting the step-out of the stepping motor, a specific number of drive pulses for driving the valve body in the closing direction are supplied to the stepping motor. Thereafter, a predetermined number of drive pulses for driving the valve body in the opening direction are supplied to the stepping motor. In this way, the origin of the closed position of the valve body is retrieved, and the retrieved origin is set.

[Patent Document 1] Japanese Patent Laid-Open No. 2004-348227

[Problems to be Solved by Invention]

As described above, in the origin search method of the closed position described in Patent Document 1, after a step-out occurs, a predetermined number of drive pulses are supplied to the stepping motor. At this time, if the current flowing in the stepping motor is large, the stepping motor generates a large torque, and the valve body is strongly pressed against the valve seat. Therefore, if the contact portion between the valve body and the valve seat is greatly deformed due to frequent origin search of the closed position, the life of the on-off valve is shortened and particles are generated.

In addition, in the above-described origin search method, since the valve body is further moved in the closing direction and the opening direction after the step-out occurs, a long time is required.

Furthermore, the stepping motor rotates to a stable point at which the torque acting on the rotor is stabilized when the step is out of step. However, this rotation amount is not always constant, and it is difficult to accurately grasp it. Therefore, if the stepping motor is operated with a preset number of drive pulses only after the step-out occurs, it is difficult to say that an appropriate closing position will be set.

An object of the present invention is to provide a processing liquid supply device and a control method of the processing liquid supply device which suppress the shortening of the life of the on-off valve and can properly close the on-off valve without a long period of time. [Technical means to solve problems]

(1) A processing liquid supply device according to an aspect of the present invention supplies a processing liquid to a substrate, and includes: a processing liquid flow path for supplying a processing liquid to be supplied to the substrate; an on-off valve including a valve seat and a valve body, and is arranged in the treatment liquid flow path; a stepping motor, which switches the on-off valve between an open state and a closed state; a driving part, which supplies drive pulses to the stepping motor; an encoder, which responds to the stepping motor A detection pulse is outputted by rotation; a control part controls a driving part based on the detection pulse output by the encoder; the switching valve is constructed in the following manner: when the self-opening state is to be switched to the closed state, the stepping motor responds to the supply by the driving The valve body is moved to the valve seat by the driving pulse; the control part controls the driving part by continuously supplying the driving pulse to the stepping motor when the on-off valve is about to switch from the open state to the closed state. When driving pulses are continuously supplied to the stepping motor and a predetermined number of continuous detection pulses are output from the encoder, the driving unit is controlled so as to stop supplying the driving pulses.

In this processing liquid supply device, when the on-off valve is to be switched from the open state to the closed state, a drive pulse is continuously supplied to the stepping motor. Thereby, the valve body is moved toward the valve seat by the rotation of the stepping motor in response to the drive pulse. At this time, a detection pulse is output from the encoder in response to the rotation of the stepping motor.

After that, if the reaction force acting on the valve body from the valve seat and the pressing force acting on the valve seat from the valve body balance when the valve body is in contact with the valve seat, the valve body stops moving and the stepping motor stops rotating. Furthermore, if the continuous predetermined number of detection pulses to be output from the encoder are not output, the supply of drive pulses is stopped. Thereby, the switching of the on-off valve from the open state to the closed state is completed, and the flow of the treatment liquid in the treatment liquid flow path is stopped.

In this case, by stopping the supply of driving pulses in the range where the stepper motor does not produce out-of-step, when the on-off valve is switched from the open state to the closed state, a large load is suppressed inside the on-off valve, thereby suppressing the internal on-off valve. deformation.

Moreover, according to the above-mentioned operation, the valve body is properly positioned with respect to the valve seat in a state where the valve body moves toward the valve seat in one direction and stops. Therefore, in order to retrieve the position of the valve body to be positioned in the closed state, it is not necessary to move the valve body in the one direction and the opposite direction with respect to the valve seat.

Furthermore, according to the above-mentioned operation, it is not necessary to desynchronize the stepping motor, so that the positional displacement of the valve body with respect to the valve seat due to the desynchronization is prevented.

As a result of the above, the shortening of the life of the on-off valve can be suppressed and the on-off valve can be properly closed without a long period of time.

(2) The control unit can control the drive unit in such a manner that the current value of the drive pulse supplied from the time when the valve body in the open state starts to move to the current switching time point before the supply stop time point of the drive pulse is greater than the current value since the current switching The current value of the drive pulse supplied from the time point to the stop time point of the supply of the drive pulse.

In this case, the torque required for the movement of the valve body can be generated by increasing the current value of the drive pulse supplied from when the valve body starts to move until the current switching time point. In this way, it is possible to prevent out-of-step due to the characteristics of the processing liquid flowing through the opening and closing valve and the frictional force generated when the valve body operates.

In addition, by reducing the current value of the drive pulse supplied from the current switching time point to the stop time point of supply of the drive pulse, the pressing force from the valve body acting on the valve seat in the closed state is suppressed from being too large. Thereby, the contact portion between the valve body and the valve seat is prevented from being greatly deformed, and the generation of particles from the contact portion is reduced.

(3) The control unit can determine that an abnormality occurs when the on-off valve is switched from the open state to the closed state, and the stepper motor is continuously supplied with drive pulses for a preset time.

In this case, replacement or maintenance of parts can be performed at an appropriate time based on the judgment of the occurrence of the abnormality.

(4) Another aspect of the present invention is a control method of a processing liquid supply apparatus for supplying a processing liquid to a substrate, wherein the processing liquid supply apparatus includes: a processing liquid flow path, the supply flow of which is to be supplied to The processing liquid of the substrate; the switch valve, which includes a valve seat and a valve body, and is arranged in the processing liquid flow path; the stepping motor, which switches the switching valve between the open state and the closed state; A drive pulse is supplied; an encoder that outputs a detection pulse in response to the rotation of the stepping motor; an on-off valve is constructed in such a manner that the stepping motor responds to the drive supplied by the drive unit when it is to be switched from the open state to the closed state The control method includes the following steps: when the switch valve is to be switched from the open state to the closed state, the driving part is controlled by continuously supplying driving pulses to the stepping motor; When the continuous predetermined number of detection pulses are not output from the encoder in response to the continuous supply of drive pulses to the stepping motor, the drive unit is controlled so as to stop supply of the drive pulses.

In the control method of the processing liquid supply device, when the on-off valve is switched from the open state to the closed state, the stepping motor is continuously supplied with a drive pulse. Thereby, the valve body is moved toward the valve seat by the rotation of the stepping motor in response to the drive pulse. At this time, a detection pulse is output from the encoder in response to the rotation of the stepping motor.

After that, if the reaction force acting on the valve body from the valve seat and the pressing force acting on the valve seat from the valve body balance when the valve body is in contact with the valve seat, the valve body stops moving and the stepping motor stops rotating. Furthermore, if the continuous predetermined number of detection pulses to be output from the encoder are not output, the supply of drive pulses is stopped. Thereby, the switching of the on-off valve from the open state to the closed state is completed, and the flow of the treatment liquid in the treatment liquid flow path is stopped.

In this case, by stopping the supply of driving pulses in the range where the stepper motor does not produce out-of-step, when the on-off valve is switched from the open state to the closed state, a large load is suppressed inside the on-off valve, thereby suppressing the internal on-off valve. deformation.

Moreover, according to the above-mentioned operation, the valve body is properly positioned with respect to the valve seat in a state where the valve body moves toward the valve seat in one direction and stops. Therefore, in order to retrieve the position of the valve body to be positioned in the closed state, it is not necessary to move the valve body in the one direction and the opposite direction with respect to the valve seat.

Furthermore, according to the above-mentioned operation, it is not necessary to desynchronize the stepping motor, so that the positional displacement of the valve body with respect to the valve seat due to the desynchronization is prevented.

As a result of the above, the shortening of the life of the on-off valve can be suppressed and the on-off valve can be properly closed without a long period of time.

(5) The control method of the treatment liquid supply device may further include the step of: using the current value of the drive pulse supplied from the time when the valve body in the open state starts to move to the current switching time point before the supply stop time point of the drive pulse The drive unit is controlled in such a way that the current value of the drive pulse supplied from the current switching time point to the stop time point of supply of the drive pulse is greater than the current value.

In this case, the torque required for the movement of the valve body can be generated by increasing the current value of the drive pulse supplied from when the valve body starts to move until the current switching time point. In this way, it is possible to prevent out-of-step due to the characteristics of the processing liquid flowing through the opening and closing valve and the frictional force generated when the valve body operates.

In addition, by reducing the current value of the drive pulse supplied from the current switching time point to the stop time point of supply of the drive pulse, the pressing force from the valve body acting on the valve seat in the closed state is suppressed from being too large. Thereby, large deformation is prevented in the contact portion of the valve body and the valve seat, and the generation of particles from the contact portion is reduced.

(6) The control method of the treatment liquid supply device may further include the following steps: when the on-off valve is to be switched from the open state to the closed state, if the driving pulse is continuously supplied to the stepping motor for a preset time, it is determined that the occurrence of abnormal.

In this case, the on-off valve can be replaced or maintained at an appropriate time based on the abnormality determination. [Effect of invention]

According to the present invention, the shortening of the life of the on-off valve can be suppressed and the on-off valve can be properly closed without a long period of time.

Hereinafter, the processing liquid supply apparatus and the control method of the processing liquid supply apparatus which concerns on embodiment of this invention are demonstrated with reference to drawings. In the following description, the so-called substrate refers to the FPD (Flat Panel Display) substrate, semiconductor substrate, optical disk substrate, magnetic disk substrate, magneto-optical disk used in liquid crystal display devices, organic EL (Electro Luminescence) display devices, etc. Substrates, photomask substrates, ceramic substrates or solar cell substrates, etc.

(1) Configuration of a substrate processing apparatus including a processing liquid supply device A substrate processing apparatus including a processing liquid supply apparatus will be described. FIG. 1 is a schematic block diagram showing the configuration of a substrate processing apparatus according to an embodiment of the present invention. As shown in FIG. 1 , the substrate processing apparatus 100 is provided adjacent to the exposure apparatus 500, and includes a coating processing unit 110, a developing processing unit 120, a thermal processing unit 130, a conveying unit 140, a control device 150, and a plurality of on-off valve devices V1 and V2. .

The coating processing unit 110 includes a plurality of coating units SC. Each coating unit SC includes a rotary chuck 91 and a discharge nozzle 92 . The rotary chuck 91 rotatably holds the unprocessed substrate W in a horizontal posture. The resist liquid is supplied to the discharge nozzle 92 through the piping p1 from the coating liquid supply source 1 provided outside the substrate processing apparatus 100 . The ejection nozzle 92 ejects the supplied resist liquid toward the upper surface of the substrate W held by the rotary chuck 91 (coating process). Thereby, a resist film is formed on one surface of the untreated substrate W. The exposure process is performed in the exposure apparatus 500 with respect to the board|substrate W on which the resist film was formed.

Furthermore, in the coating processing section 110, an antireflection film may be formed on the substrate W. As shown in FIG. In this case, the heat treatment part 130 may perform an adhesion strengthening process for improving the adhesion between the substrate W and the antireflection film. In addition, in the coating processing section 110, a resist cover film for protecting the resist film can be formed on the substrate W on which the resist film is formed.

The developing processing section 120 includes a plurality of developing units SD. Like the coating unit SC, each developing unit SD includes a rotary chuck 93 and a discharge nozzle 94 . The rotary chuck 93 rotatably holds the substrate W subjected to the exposure process by the exposure apparatus 500 in a horizontal posture. The developer is supplied to the discharge nozzle 94 through the piping p2 from the developer supply source 2 provided outside the substrate processing apparatus 100 . The ejection nozzle 94 ejects the supplied developer toward the upper surface of the substrate W held by the rotary chuck 93 (development process).

The heat treatment unit 130 performs heat treatment of the substrate W before and after the coating process performed by each coating unit SC of the coating process unit 110 , the development process performed by the developing process unit 120 , and the exposure process performed by the exposure device 500 .

The transfer unit 140 has a transfer robot that transfers the substrate W. The transfer robot of the transfer unit 140 transfers the substrate W among other transfer robots installed outside the substrate processing apparatus 100 , the coating processing unit 110 , the developing processing unit 120 , the heat treatment unit 130 , and the exposure apparatus 500 .

The control device 150 includes, for example, a CPU (Central Processing Unit), a memory, or a microcomputer, and controls the operations of the coating processing unit 110 , the developing processing unit 120 , the heat treatment unit 130 , and the conveying unit 140 .

An on-off valve device V1 for switching supply and stop of the resist liquid to the substrate W is provided in each of the plurality of coating units SC connecting the coating processing section 110 and the plurality of pipes p1 of the coating liquid supply source 1 . In addition, an on-off valve device V2 for switching the supply and stop of the developer to the substrate W is provided in each of the plurality of pipes p2 connecting the plurality of developing units SD of the development processing section 120 and the developer supply source 2 . Each of the plurality of on-off valve devices V1 and V2 is controlled by the valve control unit 200 of the control device 150 .

In the substrate processing apparatus 100 of FIG. 1, the piping p1 provided corresponding to each coating unit SC, the opening and closing valve apparatus V1, and the valve control unit 200 constitute a processing liquid supply apparatus. Moreover, the piping p2 provided corresponding to each developing unit SD, the opening and closing valve device V2, and the valve control unit 200 constitute a processing liquid supply device.

(2) The specific structure and operation of the treatment liquid supply device FIG. 2 is a block diagram for explaining the configuration of a processing liquid supply device corresponding to the coating unit SC of FIG. 1 . As shown in FIG. 2 , the processing liquid supply device 300 includes a piping p1 , an on-off valve device V1 , and a valve control unit 200 .

The opening and closing valve device V1 includes an opening and closing valve 10 , a stepping motor 20 , a switching mechanism 30 , a drive unit 40 , and an encoder 50 . The on-off valve 10 has a valve case 11 . An inner space is formed in the valve box 11 . A part of this inner space is divided by the diaphragm 12 into the flow path space 11a which forms the flow path of a process liquid (resist liquid in this example). Moreover, the valve box 11 is provided with the inflow port 11b and the outflow port 11c which communicate with the flow path space 11a. The piping p1 is connected to the inflow port 11b and the outflow port 11c.

The diaphragm 12 is formed of, for example, fluorinated resin or rubber. The central portion of the diaphragm 12 functions as the valve body 12a. Inside the valve case 11, a valve seat 11s is formed so as to face the valve body 12a with the passage space 11a interposed therebetween. The valve seat 11s has an opening 11o for leading out the processing liquid (the resist liquid in this example) in the flow path space 11a to the outflow port 11c. By moving the valve body 12a in one direction or the opposite direction with respect to the valve seat 11s, the opening 11o can be opened and closed. Hereinafter, the direction in which the valve body 12a approaches the valve seat 11s from the position away from the valve seat 11s is referred to as the closing direction, and the opposite direction is referred to as the opening direction. Furthermore, a valve stem 13 is arranged inside the valve box 11 . The valve stem 13 is connected to the valve body 12a, and extends from the valve body 12a in the opening direction.

The stepping motor 20 of this example is, for example, a two-phase stepping motor, and is used as a power source for switching the opening and closing state of the opening and closing valve 10 by moving the valve body 12 a by the valve stem 13 . Furthermore, as the stepping motor 20, a three-phase or five-phase stepping motor can be used.

The conversion mechanism 30 includes, for example, a rack and pinion mechanism, and converts the rotational force generated by the stepping motor 20 into a force for moving the valve stem 13 in the closing direction or the opening direction. In addition, the conversion mechanism 30 converts the force acting in the closing direction or the opening direction with respect to the valve stem 13 into the force for rotating the rotational axis of the stepping motor 20 in one direction or the opposite direction.

The drive unit 40 is connected to a DC power supply (not shown), and supplies drive pulses to the stepping motor 20 based on the control of the valve control unit 200 to be described later. Thereby, the stepping motor 20 rotates in one direction or the opposite direction by an angle amount corresponding to the number of supplied drive pulses.

The encoder 50 is a rotary encoder, detects the rotation amount of the rotor (not shown) of the stepping motor 20 , and outputs a pulse signal (hereinafter, referred to as a detection pulse) as the detection signal. For example, when a drive pulse is supplied to the stepping motor 20 and the stepping motor 20 rotates by an angle corresponding to the drive pulse, the encoder 50 outputs a detection pulse. On the other hand, even if a drive pulse is supplied to the stepping motor 20, the encoder 50 does not output a detection pulse when the stepping motor 20 does not rotate.

The valve control unit 200 includes an abnormality determination unit 210 , a switching determination unit 220 , a pulse control unit 230 , a current adjustment unit 240 , and a setting memory unit 250 . These functional parts are realized by, for example, the CPU of the control device 150 in FIG. 1 executing a computer program stored in the memory. In addition, a part or all of the above-mentioned structure can be implemented by hardware, such as an electronic circuit.

The operation of each functional unit of the valve control unit 200 will be described together with the opening and closing operation of the opening and closing valve 10 . FIG. 3 is a diagram showing an example of the opening and closing operation of the opening and closing valve 10 of FIG. 2 . In the upper section of FIG. 3 , the time-dependent change of the position of the valve body 12 a is shown by a curve. In the graph in the upper part of FIG. 3 , the vertical axis represents the relative position of the valve body 12a with respect to the valve seat 11s, and the horizontal axis represents time. On the vertical axis, advancing in the direction of the arrow means that the valve body 12a moves in the opening direction, and advancing in the direction opposite to the direction of the arrow means moving the valve body 12a in the closing direction. The lower section of FIG. 3 shows the internal state of the on-off valve 10 from a plurality of time points t0 to t5 shown by the curve in the upper section in a schematic cross-sectional view.

In this example, the on-off valve 10 is in a closed state at the initial state of the time point t0. The initial position of the valve body 12a at this time is represented by the symbol pp. The valve control unit 200 instructs the on-off valve 10 to switch from the closed state to the open state when the coating unit SC of FIG. 1 starts to supply the resist liquid to the substrate W. In addition, when the coating unit SC stops supplying the resist liquid to the substrate W, the on-off valve 10 is instructed to switch from the open state to the closed state.

In the setting memory part 250 of FIG. 2, the number of driving pulses (hereinafter, referred to as the number of opening pulses) m which is preset for switching the on-off valve 10 from the closed state to the open state is stored. The opening pulse number m is 400, for example. Moreover, in the setting memory part 250, the 1st electric current value of the drive pulse preset in order to switch the on-off valve 10 from a closed state to an open state is memorize|stored. The first current value is set so as not to cause the stepping motor 20 to step out of step in consideration of the characteristics of the processing liquid (in this example, the resist liquid) flowing through the on-off valve 10 and the frictional force generated when the valve body 12 a moves. is a larger value (eg 0.2(A)).

When the on-off valve 10 is instructed to switch from the closed state to the open state at the time point t0 in FIG. 3 , the pulse control unit 230 continuously supplies the stepping motor 20 with the opening pulse number m with the drive pulse for moving the valve body 12 a in the opening direction. The driving part 40 is controlled in this way. In addition, the current adjustment unit 240 controls the drive unit 40 so that the current value of the drive pulse becomes the first current value.

Thereby, from the time point t0 to the time point t1 , the valve body 12 a moves from the initial position pp to the position pa corresponding to the open state of the on-off valve 10 . Thereby, the resist liquid flows through the pipe p1 through the on-off valve 10 .

The setting memory unit 250 stores a preset number of drive pulses (hereinafter referred to as the number of closing pulses) n for switching the current value of the drive pulses when switching the on-off valve 10 from the open state to the closed state. The number n of closing pulses is equal to or less than the number m of opening pulses. The difference (difference) between the number n of OFF pulses and the number m of ON pulses is preferably 0 or more and 1/2 or less of the ON pulse number m, preferably 0 or more and 10 or less. When the number m of open pulses is 400, the number n of close pulses may be 398, for example.

Moreover, the setting memory part 250 memorize|stores the 2nd and 3rd electric current value of the drive pulse set in advance for switching the on-off valve 10 from the closed state to the open state. The second current value corresponds to the driving pulse of the number n of OFF pulses, and is the same as the first current value, and is set to a larger value (eg, 0.2 (A)) so as not to cause the stepping motor 20 to step out. The second current value may be equal to the first current value. On the other hand, the third current value is set to a value lower than the first and second current values (for example, 0.07 (A) so that the pressing force acting on the valve seat 11s from the valve body 12a when the on-off valve 10 is closed is not too large. )).

When the switching valve 10 is instructed to switch from the open state to the closed state at the time point t2, the pulse control unit 230 controls the stepping motor 20 to continuously supply the number n of closing pulses to the stepping motor 20 by driving pulses that move the valve body 12a in the closing direction. drive unit 40 . In addition, the current adjustment unit 240 controls the drive unit 40 so that the current value of the drive pulse becomes the second current value while the drive pulse of the number n of OFF pulses is supplied to the stepping motor 20 .

Therefore, when the number n of closing pulses is smaller than the number m of opening pulses, from time point t2 to time point t3 , the valve body 12a moves to the position pb which is shifted by a fixed distance in the opening direction from the position pp.

After time t3, the current adjustment unit 240 controls the drive unit 40 so that the current value of the drive pulse becomes the third current value until the on-off valve 10 is in the closed state.

When the stepping motor 20 is driven at the third current value, the reaction force acting on the valve body 12a from the valve seat 11s is balanced with the pressing force acting on the valve seat 11s from the valve body 12a, and the valve body 12a stops moving in the closing direction. move. Thereby, even when a drive pulse is supplied from the drive unit 40 to the stepping motor 20 , the detection pulse is not output from the encoder 50 .

In the setting memory unit 250, a predetermined number k, which is preset for determining that the on-off valve 10 has been switched from the open state to the closed state, is stored as a predetermined number. The switching determination unit 220 monitors the control state of the drive unit 40 by the pulse control unit 230 and monitors the detection pulse output from the stepping motor 20 . As a result of the monitoring, the switching determination section 220 determines that the switching valve 10 has completed switching to the closed state when the encoder 50 does not output a predetermined number k of detection pulses in succession in response to the continuous supply of drive pulses.

The pulse control unit 230 stops supplying the drive pulse from the drive unit 40 to the stepping motor 20 when it is determined by the switching determination unit 220 that the on-off valve 10 has been switched to the closed state.

Here, when the valve body 12a is stopped relative to the rotation of the stepping motor 20, and the stepping motor 20 is further supplied with a specific number of drive pulses in such a manner that the valve body 12a moves in the closing direction, the stepping motor 20 out of step. When the stepping motor 20 is out of step, the position of the valve body 12a changes. It is difficult to grasp the amount of change. Therefore, the above-mentioned predetermined number k is defined so that the stepping motor 20 does not lose its step, and is 2 in this example.

In the example of FIG. 3, from the time point t3 to the time point t4, the valve body 12a moves in the closing direction in response to the supply of the driving pulse, but the movement stops at the time point t4. Thereafter, at the time point t5, it is determined that the switching of the on-off valve 10 to the closed state is completed.

As described above, when the on-off valve 10 is switched to the closed state, the rotation angle of the stepping motor 20 is maintained, and the position of the valve body 12a is fixed. In the example of FIG. 3 , the valve body 12a is fixed at a position pc which is slightly shifted in the closing direction from the initial position pp. This means that the position of the valve body 12a when the on-off valve 10 is in the closed state is changed to the position pc which is more appropriate than the position pp at the time point t0. Thereby, the flow of the processing liquid (in this example, the resist liquid) in the piping p1 is appropriately blocked by the on-off valve 10 .

Since any one of the on-off valve 10 , the stepping motor 20 and the encoder 50 is abnormal during a series of operations when the on-off valve 10 is switched to the closed state, it may not be possible to accurately determine that the on-off valve 10 completes the closing state. switch.

For example, the encoder 50 does not stop supplying drive pulses to the stepping motor 20 if it cannot be determined that the switching valve 10 has completed switching to the closed state due to the continuous generation of noise having the same waveform as the detection pulse. In this case, the stepping motor 20 is out of step. Alternatively, if the valve body 12a deviates from the valve stem 13, the valve stem 13 moves beyond the position where it should stop and collides with the valve seat 11s.

Therefore, when the on-off valve 10 is switched from the open state to the closed state, the abnormality determination unit 210 determines that an abnormality has occurred when the drive pulse is continuously supplied for a predetermined predetermined time. In the example of FIG. 3 , the abnormality determination unit 210 determines that an abnormality has occurred when, for example, the drive pulse has been continuously supplied for a predetermined time period exceeding a preset time from the time point t3 . Further, the abnormality determination unit 210 outputs the determination result. In this case, replacement or maintenance of parts can be performed at an appropriate time based on the determination of abnormality.

Furthermore, the processing liquid supply device 300 may be provided with a presentation device (a display device, a sound output device, etc.) that presents the abnormality determination result output from the abnormality determination unit 210 to the user. In this case, the user can easily grasp that the on-off valve device V2 is abnormal.

The processing liquid supply device corresponding to the developing unit SD of FIG. 1 has basically the same configuration and operation as the processing liquid supply device 300 of FIGS. 3 and 4 .

(3) On-off control processing of the on-off valve 10 FIG. 4 is a flowchart showing an example of the opening and closing control process of the opening and closing valve 10 executed by the valve control unit 200 of FIG. 2 . The on-off control process is started by providing the valve control unit 200 with a command to switch the on-off state of the on-off valve 10 . In the following description, a counter is built in the valve control part 200 . In addition, a timer is built in the valve control unit 200 .

First, the pulse control unit 230 determines whether the command given at the beginning is a command to switch the on-off valve 10 from the open state to the closed state (step S11 ).

When the command at the beginning is a command to switch from the on state to the off state, the pulse control unit 230 and the current adjustment unit 240 control the drive unit 40 in such a manner as to continuously supply the stepping motor 20 with the second current value to turn off Drive pulses of the pulse number n (step S12). At this time, the drive pulse supplied to the stepping motor 20 corresponds to the movement of the valve body 12a in the closing direction. Thereby, the valve body 12a moves in the closing direction with a relatively high torque. Moreover, the switching determination part 220 resets the value of a counter, resets a timer, and starts time measurement by a timer (step S13).

Next, the abnormality determination unit 210 determines whether or not a predetermined time set in advance has elapsed since the time measurement of the timer (step S14). When the predetermined time has not elapsed from the time measurement start time of the timer, the pulse control unit 230 and the current adjustment unit 240 control the drive unit 40 so as to supply the stepping motor 20 with the third current value. A drive pulse (step S15). At this time, the drive pulse supplied to the stepping motor 20 corresponds to the movement of the valve body 12a in the closing direction.

Next, the switching determination part 220 determines whether the detection pulse is output from the encoder 50 in response to the drive pulse supplied in step S15 (step S16). When the detection pulse is output, the process returns from step S12 to step S14. On the other hand, when the detection pulse is not output, the switching determination unit 220 increments the value of the counter (step S17). Further, the switching determination unit 220 determines whether or not the detection pulse is not output continuously for a predetermined number k based on the value of the counter (step S18).

In the case where the detection pulse is not output and the predetermined number of k is not continuous, the process returns from step S18 to step S14. On the other hand, when the detection pulse is not outputted continuously for a predetermined number of k, the switch control process is ended in a state where the supply of the drive pulse to the stepping motor 20 is stopped.

In the above-mentioned step S11, when the command at the beginning is the command to switch to the open state, the pulse control unit 230 controls the drive unit 40 in such a manner that the number of open pulses is continuously supplied to the stepping motor 20 with the first current value. m driving pulse (step S19). At this time, the drive pulse supplied to the stepping motor 20 corresponds to the movement of the valve body 12a in the opening direction. Thereby, the valve body 12a moves in the opening direction with a relatively high torque. After that, the switch control process ends.

In the above-mentioned step S14, when a preset predetermined time has elapsed from the start of time measurement by the timer, the abnormality determination unit 210 determines that an abnormality has occurred, and outputs the determination result to the outside of the valve control unit 200 (step S20). ). After that, the switch control process ends.

(4) Effect (a) In the above-described processing liquid supply device 300 , when the on-off valve 10 is switched from the open state to the closed state, a drive pulse is continuously supplied to the stepping motor 20 . The valve body 12a is moved toward the valve seat 11s by the rotation of the stepping motor 20 in response to the drive pulse. At this time, a detection pulse is output from the encoder 50 in response to the rotation of the stepping motor 20 .

When the valve body 12a is in contact with the valve seat 11s, the reaction force acting on the valve body 12a from the valve seat 11s is balanced with the pressing force acting on the valve seat 11s from the valve body 12a, and the valve body 12a stops moving in the closing direction. The stepping motor 20 stops rotating. Next, if the continuous predetermined number k of detection pulses to be output from the encoder 50 are not output, the supply of drive pulses is stopped. Thereby, the switching of the on-off valve 10 from the open state to the closed state is completed, and the flow of the processing liquid in the pipes p1 and p2 is stopped.

In this case, the supply of the drive pulse is stopped in the range where the stepper motor 20 does not cause out-of-step, so that when the on-off valve 10 is switched on and off, a large load is prevented from being generated inside the on-off valve 10 . Thereby, deformation inside the on-off valve 10 is suppressed.

Moreover, according to the above-mentioned operation, the valve body 12a is appropriately positioned with respect to the valve seat 11s in a state where the valve body 12a is moved in the closing direction and stopped. Therefore, in order to search for the position of the valve body 12a to be positioned in the closed state, it is not necessary to move the valve body 12a in the opening direction and the closing direction with respect to the valve seat 11s, respectively.

Furthermore, according to the above-mentioned operation, it is not necessary to desynchronize the stepping motor 20, so that the positional displacement of the valve body 12a with respect to the valve seat 11s due to the desynchronization is prevented.

As a result of the above, the shortening of the life of the on-off valve 10 can be suppressed and the on-off valve 10 can be properly closed without a long period of time.

(b) In the above-mentioned processing liquid supply device 300, when the on-off valve 10 is switched from the open state to the closed state, the stepping motor 20 is driven with the second current value while the drive pulses of the number n of close pulses are supplied to the stepping motor 20. 20. Thereby, the step-out is prevented from occurring due to the characteristics of the processing liquid flowing through the opening and closing valve and the frictional force generated when the valve body 12a operates.

After that, until the supply of the drive pulse is stopped, the current value of the drive pulse supplied to the stepping motor 20 is changed to the third current value. In this case, the pressing force acting on the valve seat 11s from the valve body 12a in the closed state is suppressed from being too large. Accordingly, the contact portion of the valve body 12a and the valve seat 11s is prevented from being greatly deformed, and the generation of particles from the contact portion is reduced.

(5) Other Embodiments (a) In the above-described embodiment, when the supply and stop of the processing liquid (resist liquid, developer, etc.) to the substrate W is switched, the switching state of the on-off valve 10 of the processing liquid supply device 300 is switched, but this The invention is not limited to this.

The command for switching the on-off state of the on-off valve 10 can be provided to the valve control unit 200 by the user operating the operating unit of the substrate processing apparatus 100 (not shown). In this case, the user can instruct the switching operation of the on-off valve 10 similar to the example of FIG.

In addition, as shown in FIG. 3 , a series of actions for sequentially switching the on-off valve 10 in the closed state to the open state and the closed state can also be performed automatically every fixed cycle or a certain number of batches. Alternatively, when the power supply of the substrate processing apparatus 100 is turned on, it may be automatically performed as an initialization operation of each unit (in the above example, the coating unit SC and the developing unit SD).

(b) In the above-described embodiment, the processing liquid supply device is applied to the resist liquid supply system for supplying the resist liquid to the substrate W and the developer liquid supply system for supplying the developer liquid to the substrate W, respectively, but the present invention is not limited to this. .

The processing liquid supply device of the present invention can be applied to a coating liquid supply system for supplying various coating liquids for forming an antireflection film, a resist coating film, and the like on the substrate W. Alternatively, the processing liquid supply device of the present invention may be applied to a cleaning liquid supply system for supplying a cleaning liquid such as pure water or a chemical liquid to the substrate W.

(c) In the above-described embodiment, a rotary encoder is used as the encoder 50 for detecting the rotation of the stepping motor 20, but the present invention is not limited to this. The encoder 50 can also be a linear encoder for detecting the movement of the valve stem 13 in the opening and closing directions. In this case, the movement of the valve stem 13 in the opening and closing directions detected by the linear encoder can be detected as the rotation of the stepping motor 20 .

(d) In the above-described embodiment, the current value of the drive pulse supplied to the stepping motor 20 is changed in two steps when the on-off valve 10 is switched from the open state to the closed state, but the present invention is not limited to this. The current value of the drive pulse supplied to the stepping motor 20 when the on-off valve 10 is switched from the open state to the closed state may be fixed. When the torque required to move the valve stem 13 is very small due to the low viscosity of the treatment liquid or the small friction force generated when the valve stem 13 moves, the current value should be set to the third above. current value.

(6) Correspondence between the constituent elements of the technical solution and the elements of the embodiment Hereinafter, an example of the correspondence between the constituent elements of the technical solution and the elements of the embodiment will be described. In the above-mentioned embodiment, the resist liquid and the developing liquid are examples of the processing liquid, the pipes p1 and p2 are examples of the processing liquid flow paths, and the valve control unit 200 is an example of the control section, and all driving pulses of the number n of closing pulses are supplied to The time point of the stepping motor 20 (the time point t3 in FIG. 3 ) is an example of the current switching time point.

As each constituent element of the technical solution, various other elements having the structure or function described in the technical solution can also be used.

1: Coating liquid supply source 2: Developer supply source 10: On-off valve 11: valve box 11a: Flow path space 11b: Inflow port 11c: Outgoing port 11o: Opening 11s: valve seat 12: Diaphragm 12a: valve body 13: Stem 20: Stepper Motor 30: Conversion Agency 40: Drive Department 50: Encoder 91: Rotary chuck 92: spray nozzle 93: Rotary chuck 94: Spray Nozzle 100: Substrate processing device 110: Coating processing department 120: Development processing department 130: Heat Treatment Department 140:Conveying Department 150: Controls 200: Valve Control Department 210: Abnormal Determination Department 220: Switching Judgment Section 230: Pulse Control Department 240: Current adjustment part 250: Setting memory 300: Treatment liquid supply device 500: Exposure device p1: piping p2: piping SC: coating unit SD: developing unit V1: On-off valve device V2: On-off valve device W: substrate

FIG. 1 is a schematic block diagram showing the configuration of a substrate processing apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram for explaining the configuration of a processing liquid supply device corresponding to the developing unit of FIG. 1 . FIG. 3 is a diagram showing an example of the opening and closing operation of the opening and closing valve of FIG. 2 . FIG. 4 is a flowchart showing an example of the opening and closing control processing of the opening and closing valve executed by the valve control unit of FIG. 2 .

10: On-off valve

11: valve box

11a: Flow path space

11b: Inflow port

11c: Outgoing port

11o: Opening

11s: valve seat

12: Diaphragm

12a: valve body

13: Stem

20: Stepper Motor

30: Conversion Agency

40: Drive Department

50: Encoder

92: spray nozzle

200: Valve Control Department

210: Abnormal Determination Department

220: Switching Judgment Section

230: Pulse Control Department

240: Current adjustment part

250: Setting memory

300: Treatment liquid supply device

p1: piping

V1: On-off valve device

Claims (6)

A processing liquid supply device, which supplies processing liquid to a substrate, and includes: a processing liquid flow path, which supplies the processing liquid to be supplied to the substrate; an on-off valve, which includes a valve seat and a valve body, and is arranged in the above-mentioned processing liquid flow path; a stepping motor, which switches the on-off valve between an open state and a closed state; a drive unit that supplies drive pulses to the stepping motor; an encoder that outputs detection pulses in response to the rotation of the stepping motor; a control unit that controls the drive unit based on detection pulses output by the encoder; and The on-off valve is configured such that when the open state is to be switched to the closed state, the stepping motor is rotated in response to the drive pulse supplied from the drive unit, whereby the valve body moves toward the valve seat, The control unit controls the drive unit so as to continuously supply the drive pulse to the stepping motor when the on-off valve is about to be switched from the open state to the closed state. When a predetermined number of continuous detection pulses are output from the encoder by driving pulses, the driving section is controlled so as to stop supplying the driving pulses. The treatment liquid supply device according to claim 1, wherein the control section controls the drive section from the start of movement of the valve body in the open state to the current switching time point before the supply stop time point of the drive pulse The current value of the drive pulse supplied up to this point is greater than the current value of the drive pulse supplied from the current switching time point to the stop time point of supplying the drive pulse. The processing liquid supply device according to claim 1 or 2, wherein when the on-off valve is to be switched from the open state to the closed state, the control unit continuously supplies the drive pulse to the stepping motor for a predetermined time period. In this case, it is determined that an abnormality has occurred. A control method of a processing liquid supply apparatus, which is a control method of a processing liquid supply apparatus for supplying a processing liquid to a substrate, and The above-mentioned treatment liquid supply device includes: a processing liquid flow path, which supplies the processing liquid to be supplied to the substrate; an on-off valve, which includes a valve seat and a valve body, and is arranged in the above-mentioned processing liquid flow path; a stepping motor, which switches the on-off valve between an open state and a closed state; a drive unit that supplies drive pulses to the stepping motor; an encoder that outputs detection pulses in response to the rotation of the stepping motor; The on-off valve is configured such that, when switching from the open state to the closed state, the stepping motor is rotated in response to the drive pulse supplied from the drive unit, whereby the valve body moves toward the valve seat. , The above-mentioned control method includes the following steps: When the on-off valve is to be switched from the open state to the closed state, the drive part is controlled in a manner of continuously supplying the drive pulse to the stepping motor; If the continuous predetermined number of detection pulses are not output from the encoder in response to the continuous supply of the drive pulses to the stepping motor, the drive unit is controlled to stop supply of the drive pulses. The control method of a treatment liquid supply device according to claim 4, further comprising the step of: supplying the current from the start of the movement of the valve body in the open state to the current switching time point before the supply stop time point of the drive pulse The driving unit is controlled such that the current value of the driving pulse is larger than the current value of the driving pulse supplied from the current switching time point to the supply stop time point of the driving pulse. The control method for a treatment liquid supply device according to claim 4 or 5, further comprising the step of: when the on-off valve is to be switched from the open state to the closed state, if the drive pulse is continuously supplied to the stepping motor for a continuous period of time In the case of the preset time, it is determined that an abnormality occurs.

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