JP2006316711A - Chemical liquid supply system and chemical liquid supply pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chemical liquid supply system controlling the suction or discharge flow rate of a chemical liquid with high accuracy and eliminating an adverse effect caused by heat generation. <P>SOLUTION: A bellows type partition member 12 is received as a capacity variable member in a pump housing 11 of a chemical liquid supply pump 10, and a pump chamber 13 and a pressure acting chamber 14 are separately formed by the bellows type partition member 12. The pressure acting chamber 14 is connected with an electropneumatic regulator 28. A rod 33 is coupled to the bellows type partition member 12 and a displacement of the rod 33 is detected by a position detector 36. A controller 40 sets a target operation amount of the bellows in suction or discharge of the chemical liquid and controls the electropnuematic regulator 28 based on a difference between the target operation amount and an actual operation amount obtained from a detection result by the position detector 36. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a chemical solution supply system for inhaling and discharging a chemical solution by a chemical solution supply pump and dropping the discharged chemical solution. Specifically, the present invention relates to a semiconductor manufacturing process such as a chemical solution application process such as a photoresist solution. The present invention relates to a chemical solution supply system suitable for use in a chemical solution use process of an apparatus. The present invention also relates to a chemical solution supply pump suitable for use in a chemical solution use process of a semiconductor manufacturing apparatus such as a chemical solution application process such as a photoresist solution.

  In a chemical solution use process of a semiconductor manufacturing apparatus, a chemical solution supply pump is used to apply a predetermined amount of a chemical solution such as a photoresist solution to a semiconductor wafer. As the chemical solution supply pump, the pump chamber filled with the chemical solution and the pressure working chamber for introducing compressed air are separated by a flexible membrane such as bellows or diaphragm, and the air pressure in the pressure working chamber is variably adjusted. There is one in which a film is deformed to suck and discharge a chemical solution.

  In the configuration in which the flexible film is deformed by air pressure as described above, it is difficult to finely adjust the deformation speed of the flexible film, and the discharge flow rate of the chemical solution cannot be controlled with high accuracy. It was.

  In contrast, there is a chemical supply pump in which a flexible film is deformed by an electric motor instead of air pressure, and the chemical liquid is sucked and discharged by the deformation (see, for example, Patent Document 1). According to such control by the electric motor, the deformation speed of the flexible film can be finely controlled.

However, in the case of a chemical solution supply pump using an electric motor, heat is generated when continuous operation is performed at a high load or at a high speed, so that there is a problem that it cannot be used when temperature control of the chemical solution is required. In addition, when using chemicals used in the semiconductor manufacturing process, especially hydrochloric acid, the chemicals may permeate even if corrosion resistance is prevented by using tetrafluoroethylene resin (trade name Teflon) as the wetted material. There was a problem that it was unsuitable for the use of an electric motor. In addition, the configuration having an electric motor is expensive because a complicated mechanism may be required for power transmission and deceleration, and there is a problem that miniaturization of the pump is hindered.
JP-A-10-54368

  The main object of the present invention is to provide a chemical solution supply system that can control the flow rate of the suction or discharge of a chemical solution with high accuracy and eliminate the adverse effects of heat generation.

  Hereinafter, effective means for solving the above-described problems will be described while showing effects and the like as necessary. In the following, in order to facilitate understanding, a corresponding configuration example in the embodiment of the invention is appropriately shown in parentheses, etc., but is not limited to the specific configuration shown in parentheses.

Means 1. There is a pump chamber (pump chamber 13) for filling a chemical solution, and a pressure working chamber (pressure working chamber 14) partitioned from the pump chamber by a variable volume member (bellows type partitioning member 12), and the pressure A chemical supply pump (chemical supply pump 10) that operates the volume variable member according to the gas pressure in the working chamber, and sucks or discharges the chemical based on the volume change of the pump chamber that accompanies the operation;
Pressure adjusting means (electropneumatic regulator 28) for adjusting the pressure of the gas supplied to the pressure working chamber;
An operation amount detection means (position detector 36) for detecting an operation amount of the volume variable member;
Based on the deviation between the target operating amount and the actual operating amount obtained from the detection result of the operating amount detecting means while setting the target operating amount of the volume variable member at the time of suction or discharge of the chemical solution by the chemical solution supply pump Control means (controller 40) for controlling the pressure adjusting means;
A chemical supply system characterized by comprising:

  According to the means 1, the target operation amount of the volume variable member is set at the time of the suction or discharge of the chemical liquid by the chemical liquid supply pump, and the actual operation amount obtained from the target operation amount and the detection result by the operation amount detection means The pressure adjusting means is controlled based on the deviation. In such a case, since the operation amount of the variable volume member and the change in volume of the pump chamber are generally correlated, feedback control of the operation amount of the variable volume member as described above substantially reduces the change in volume of the pump chamber. You will be able to control as you wish. Thereby, it becomes possible to control the suction flow rate or the discharge flow rate of the chemical liquid to a desired flow rate with high accuracy. In addition, since the chemical liquid supply pump performs the suction or discharge of the chemical liquid using the gas pressure (for example, air pressure) adjusted by the pressure adjusting means as a driving source, it differs from the electric system that controls the flow rate by the electric motor. There is no risk of adverse effects, and even a chemical solution requiring temperature control can be suitably used.

  For example, as a feedback control method for the discharge flow rate, a configuration in which a flow rate sensor, a variable throttle, or the like is provided in the chemical discharge passage is also conceivable. Deterioration or the like occurs, and special processing is forced to prevent corrosion of the sensor or the like by chemicals. In this regard, according to the configuration of the present means, there is no fear of the above-described inconvenience, a simple system configuration can be realized, and as a result, the system can be reduced in size and cost.

  Mean 2. The chemical solution supply system according to claim 1, further comprising means for calculating a discharge flow rate of the chemical solution based on a detection result by the operation amount detection means.

  As described above, since the operation amount of the variable volume member and the volume change of the pump chamber have a correlation, the discharge flow rate of the chemical liquid can be calculated based on the detection result by the operation amount detection means. For example, in a configuration in which the discharge flow rate is measured by a flow sensor provided in a chemical flow passage (discharge passage or the like), it is necessary to consider changes in the characteristics of the chemical liquid (changes in specific gravity, viscosity, etc.) due to temperature changes, etc. According to the above means, the discharge flow rate can be calculated corresponding to the volume change of the pump chamber without being affected by the change in the characteristics of the chemical solution.

  Means 3. The control means sets a target value of the moving speed of the variable volume member as the target operating amount, and the actual moving speed of the variable volume member obtained based on the target value and the detection result by the operating amount detecting means. The chemical liquid supply system according to means 1 or 2, wherein the pressure adjusting means is controlled based on a deviation from the above.

  According to the means 3, since the moving speed of the variable volume member can be controlled as desired, an appropriate chemical solution discharge operation can be realized every time even when the chemical solution discharge operation is repeated.

  Means 4. The relationship between the operation amount of the volume variable member and the pump discharge amount is defined, and the control means sets the target value of the moving speed based on the flow rate command value each time using the relationship. The chemical solution supply system according to claim 3.

  According to the means 4, the relationship between the operation amount of the variable volume member and the pump discharge amount is defined, and the target value of the moving speed of the variable volume member is set based on the flow rate command value each time using this relationship. . In this case, the target value of the moving speed can be easily set.

  Means 5. Means for linearizing the relationship between the operation amount of the volume variable member and the pump discharge amount for each section divided into a plurality of sections within the operation range of the volume variable member, and the control means uses the linearized relationship 5. The chemical solution supply system according to any one of means 1 to 4, wherein the pressure adjusting means is controlled.

  As described above, the operation amount of the variable volume member and the volume change of the pump chamber (pump discharge amount) are generally correlated, but strictly speaking, the operation of the variable volume member depends on what is used as the variable volume member. It is considered that the quantity and the volume change of the pump chamber are nonlinear. In this respect, the means 5 linearizes the relationship between the operation amount of the variable volume member and the pump discharge amount for each of the sections divided into a plurality within the operation range of the variable volume member, and the pressure adjusting means using the linearized relationship. To control. Thereby, the volume in the pump chamber can be appropriately changed, and as a result, the control accuracy of the suction flow rate or the discharge flow rate of the chemical liquid is improved.

Means 6. A chemical liquid supply system that uses an axially expandable / contractible bellows (bellows 15) as the volume variable member of the chemical liquid supply pump, and the amount of expansion / contraction of the bellows is detected by the operation amount detection means as the operation amount of the volume variable member. Because
The chemical solution supply system according to any one of means 1 to 5, wherein the control means controls the pressure adjusting means on the basis of the expansion / contraction amount of the bellows.

  The bellows expands and contracts in the axial direction, and at that time, the volume change amount of the pump chamber with respect to the expansion / contraction amount of the bellows (that is, the amount of the chemical at the time of suction / discharge) becomes substantially linear. Therefore, by controlling the pressure adjusting means based on the expansion / contraction amount of the bellows, the volume in the pump chamber can be appropriately changed, and the control accuracy of the chemical liquid suction flow rate or the discharge flow rate is improved.

Mean 7 A chemical solution supply system in which a diaphragm (diaphragm 53) is used as a volume variable member of the chemical solution supply pump, and the deformation amount of the diaphragm is detected as an operation amount of the volume variable member by the operation amount detection means,
Means for linearizing the relationship between the diaphragm deformation amount and the pump discharge amount for each section divided into a plurality of sections within the deformation range of the diaphragm, and the control means uses the linearized relationship to control the pressure adjusting means. The chemical solution supply system according to any one of means 1 to 4, wherein the chemical solution supply system is controlled.

  In the chemical solution supply system using a diaphragm, unlike the system using a bellows, the volume change amount of the pump chamber with respect to the diaphragm deformation amount (that is, the chemical solution amount during suction / discharge) is not linear. However, if the diaphragm deformation range is divided into a plurality of sections and viewed in each section, the relationship of the volume change amount of the pump chamber to the diaphragm deformation amount can be approximated to a linear characteristic. In such a case, the means 7 linearizes the relationship between the diaphragm deformation amount and the pump discharge amount for each of the sections divided into a plurality within the deformation range of the diaphragm, and controls the pressure adjusting means using the linearized relationship. Thereby, the volume in the pump chamber can be appropriately changed, and as a result, the control accuracy of the suction flow rate or the discharge flow rate of the chemical liquid is improved.

  The configuration using the diaphragm as the variable volume member has an advantage that the liquid pool is small as compared with the configuration using the bellows. Therefore, it is possible to realize a chemical solution supply system that has a small amount of liquid pool and enables highly accurate chemical solution flow rate control.

  Means 8. 8. The chemical solution supply system according to claim 7, wherein the relationship between the diaphragm deformation amount and the pump discharge amount is linearized by linear interpolation based on the diaphragm deformation amount and the pump discharge amount at the boundary point of each section.

  According to the means 8, if each data of the diaphragm deformation amount and the pump discharge amount at the boundary point of each section is prepared in advance, the diaphragm deformation amount and the pump discharge amount are calculated by linear interpolation based on each data. The relationship can be linearized. In such a case, linearization of the above relationship can be easily realized.

  Means 9. The object to be detected (rod 33) is connected to the variable volume member on the pressure acting chamber side, and the operation amount detection means detects the amount of movement of the object to be detected as the operation amount of the volume variable member. The chemical solution supply system according to any one of means 1 to 8.

  According to the means 9, since the movement of the detected object accompanying the operation of the variable volume member is detected on the pressure acting chamber side isolated from the pump chamber, the position detector or the like constituting the operation amount detecting means is used as the chemical solution. There is no risk of exposure. Therefore, it is not necessary to take measures for preventing corrosion by chemical solutions for the position detector and the like, and a simple and inexpensive system can be realized.

  Means 10. The chemical solution supply system according to any one of means 1 to 9, wherein a plurality of the chemical solution supply pumps are provided, and each of these pumps is alternately operated for suction and discharge.

  In the chemical solution supply pump having the above-described configuration, the suction and discharge of the chemical solution are alternately repeated in the same pump chamber. Therefore, in the configuration using the single chemical solution supply pump, the discharge of the chemical solution is intermittently performed. In this regard, by alternately performing a suction operation and a discharge operation of a plurality of chemical liquid supply pumps as in the means 10, it becomes possible to continuously perform the discharge of the chemical liquid without interruption.

  In particular, as described above, in the configuration in which the moving speed of the variable volume member is feedback-controlled, the time required for the chemical liquid discharge by each pump can be made constant each time, so that the chemical liquid supply can be stabilized.

Means 11. Applying a chemical supply pump provided with a biasing means (compression coil spring 35) for biasing the volume variable member in a direction opposite to the gas pressure in the pressure working chamber;
Means for calculating the pressure in the pump chamber based on the operation amount of the volume variable member detected by the operation amount detection means and the gas pressure in the pressure acting chamber;
The chemical solution supply system according to any one of means 1 to 10, further comprising means for controlling the pressure in the pump chamber by the calculated pressure in the pump chamber.

In the means 11, the gas pressure in the pressure acting chamber acts on the volume variable member from one side, and the urging force by the urging means and the pressure in the pump chamber act from the other side. The variable volume member is controlled at a position where these forces are balanced. In this case, if the force received by the variable volume member by the gas pressure in the pressure acting chamber is Fs, the force received by the variable volume member by the biasing means is Fb, and the force received by the variable volume member by the pressure in the pump chamber is Fp,
Fs = Fb + Fp
The relationship is established. Here, Fb (force that the variable volume member receives by the biasing means) correlates with the operation amount of the variable volume member, and can be calculated based on the operation amount of the variable volume member. Fs (the force received by the variable volume member due to the gas pressure in the pressure action chamber) can be calculated from the gas pressure in the pressure action chamber. The pressure in the pump chamber can be calculated from Fp (the force received by the variable volume member due to the pressure in the pump chamber) and the pressure receiving area of the variable volume member. As described above, the pressure in the pump chamber can be calculated based on the operation amount of the variable volume member and the gas pressure in the pressure acting chamber. And proper pressure control is attained by implementing the pressure control in the said pump chamber by the pressure in this pump chamber.

  Further, the configuration of the means 11 eliminates the need for a pressure sensor for detecting the pressure in the pump chamber. As a result, there is no sensor device or the like that is directly exposed to the chemical solution, so that no countermeasure against corrosion due to the chemical solution is imposed, and the configuration can be simplified and the cost can be reduced.

Means 12. Applying a chemical supply pump provided with a biasing means (compression coil spring 35) for biasing the volume variable member in a direction opposite to the gas pressure in the pressure working chamber;
Means for calculating the pressure in the pump chamber based on the operation amount of the volume variable member detected by the operation amount detection means and the gas pressure in the pressure acting chamber;
The chemical liquid supply according to any one of means 1 to 10, further comprising means for determining whether clogging has occurred in the chemical liquid discharge passage leading to the pump chamber by the calculated pressure in the pump chamber. system.

As described in the means 11, the force (Fs) received by the variable volume member due to the gas pressure in the pressure working chamber, the force (Fb) received by the variable volume member by the biasing means, and the pressure in the pump chamber, Depending on the balance with the force (Fp)
Fs = Fb + Fp
In this case, the pressure in the pump chamber can be calculated based on the operation amount of the variable volume member and the gas pressure in the pressure acting chamber. At this time, if clogging occurs in the chemical solution discharge path, the pressure in the pump chamber increases due to pressure loss even if the chemical solution discharge amount is the same. Therefore, occurrence of clogging can be determined.

  For example, it is preferable to determine in advance a pressure determination value when performing discharge amount control at a predetermined discharge flow rate, and to determine that clogging has occurred when the calculated pressure in the pump chamber becomes greater than the pressure determination value. The pressure determination value may be determined based on an initial (new) pressure value. By performing the clogging determination, it is possible to eliminate a process defect caused by the clogging.

  Further, the configuration of the means 12 eliminates the need for a pressure sensor for detecting the pressure in the pump chamber. As a result, there is no sensor device or the like that is directly exposed to the chemical solution, so that no countermeasure against corrosion due to the chemical solution is imposed, and the configuration can be simplified and the cost can be reduced.

Means 13. Applying a chemical supply pump having a suction valve (suction valve 23) on the suction passage side leading to the pump chamber and a discharge valve (discharge valve 25) on the discharge passage side leading to the pump chamber,
The state in which the suction valve is closed and the discharge valve is opened and the suction valve is closed and the discharge valve is opened after the completion of the discharge when the chemical solution is discharged in accordance with the operation of the variable volume member. The chemical solution supply system according to any one of means 1 to 12, wherein the suction of the chemical solution is started by reversing the operation of the variable volume member while maintaining the state.

  According to the means 13, when the chemical liquid is discharged from the chemical liquid supply pump, the suction valve is closed and the discharge valve is opened, and the chemical liquid is discharged from the pump chamber in accordance with the operation of the variable volume member. Then, after the discharge of the chemical liquid is completed, the state where the suction valve is closed and the discharge valve is opened is temporarily continued, and the operation of the variable volume member is reversed and the suction of the chemical liquid is started. At this time, suck back is performed by the suction operation of the chemical liquid in a state where the suction valve is closed and the discharge valve is opened. Thereby, it is possible to prevent liquid dripping at the nozzle below the medicine droplet. In the above configuration, the on / off valve for suck back is not necessary, and thus the configuration can be simplified.

  Means 14. 14. The chemical liquid supply according to claim 13, wherein after the completion of the discharge of the chemical liquid, the time for performing the chemical liquid suction operation with the suction valve closed and the discharge valve opened, or the suction speed is variably controlled. system.

  According to the means 14, the suck back operation of the chemical liquid can be arbitrarily controlled, and the suck back amount can be controlled as desired.

Means 15. There is a pump chamber (pump chamber 105) for filling a chemical solution, and a diaphragm operation chamber (diaphragm operation chamber 106) that is partitioned from the pump chamber by a diaphragm (diaphragm 103), and the volume change of the diaphragm operation chamber The diaphragm is bent and deformed according to the pressure, and the liquid supply pump sucks or discharges the liquid chemical based on the volume change of the pump chamber accompanying the deformation.
A movable body (plunger 119) that fills the diaphragm operation chamber and a fluid chamber (fluid chamber 123) communicating with the diaphragm operation chamber with an incompressible fluid and linearly changes the volume of the fluid chamber with respect to an operation amount. Pressure adjusting means for adjusting the pressure of the gas in the pressure operation chamber in a pressure operation chamber (pneumatic operation chamber 122) provided on the opposite side of the diaphragm operation chamber across the movable body A chemical supply pump characterized by connecting an electropneumatic regulator 127.

  In the chemical solution supply pump of the means 15, the pressure of the gas in the pressure operation chamber is adjusted by the pressure adjusting means, and the movable body is operated by the pressure adjustment. When the movable body is operated, the volume of the fluid chamber changes linearly with respect to the operation amount, and the volume of the diaphragm operation chamber changes accordingly. The diaphragm bends and deforms in accordance with the volume change of the diaphragm operation chamber, and the suction or discharge of the chemical solution is performed based on the volume change of the pump chamber accompanying the diaphragm deformation. At this time, the diaphragm operation chamber and the fluid chamber are filled with an incompressible fluid, and the volume change of the fluid chamber and the volume change of the diaphragm operation chamber coincide (the increase in one becomes the decrease in the other). . Further, the volume change of the fluid chamber with respect to the operation amount of the movable body is linear. Therefore, the flow rate at the time of suction or discharge of the chemical liquid can be controlled with high accuracy based on the operation amount of the movable body.

  Means 16. The chemical solution supply pump according to claim 15, wherein the effective sectional area of the movable body is smaller than the effective sectional area of the diaphragm.

  According to the means 16, since the effective sectional area of the movable body is smaller than the effective sectional area of the diaphragm, when the diaphragm is bent and deformed, the operation amount of the movable body becomes larger than the deformation amount of the diaphragm. Therefore, the amount of deformation of the diaphragm can be finely controlled.

  Means 17. The means 15 or 16 is characterized in that the movable body is a plunger having a shape having a relatively small area on the side facing the fluid chamber and a relatively large area on the side facing the pressure operation chamber. Chemical supply pump.

  According to the means 17, since the pressure receiving area on the pressure operation chamber side is relatively large in the plunger, a sufficient force can be applied when the plunger is moved by the gas pressure. Thereby, the responsiveness of the plunger is improved, and as a result, the deformation speed of the diaphragm (e.g., the discharge amount of the chemical solution) can be arbitrarily controlled.

Means 18. A chemical supply pump according to any one of means 15 to 17,
An operation amount detection means (position detector 135) for detecting the operation amount of the movable body;
Based on the deviation between the target operating amount and the actual operating amount obtained from the detection result by the operating amount detecting means while setting the target operating amount of the movable body at the time of suction or discharge of the chemical liquid by the chemical liquid supply pump Control means (controller 140) for controlling the pressure adjusting means;
A chemical supply system characterized by comprising:

  According to the means 18, the target operation amount of the movable body (a plunger or the like whose operation amount is controlled by the gas pressure) is set at the time of suction or discharge of the chemical solution by the chemical supply pump, and the target operation amount and the operation amount detection are set. The pressure adjusting means is controlled based on the deviation from the actual operation amount obtained from the detection result by the means. In such a case, since the operation amount of the movable body and the volume change of the pump chamber have a correlation, feedback control of the operation amount of the movable body as described above substantially changes the volume of the pump chamber as desired. You will be able to control. Thereby, it becomes possible to control the suction flow rate or the discharge flow rate of the chemical liquid to a desired flow rate with high accuracy. In addition, since the chemical liquid supply pump performs the suction or discharge of the chemical liquid using the gas pressure (for example, air pressure) adjusted by the pressure adjusting means as a driving source, it differs from the electric system that controls the flow rate by the electric motor. There is no risk of adverse effects, and even a chemical solution requiring temperature control can be suitably used.

  For example, as a feedback control method for the discharge flow rate, a configuration in which a flow rate sensor, a variable throttle, or the like is provided in the chemical discharge passage is also conceivable. Deterioration or the like occurs, and special processing is forced to prevent corrosion of the sensor or the like by chemicals. In this regard, according to the configuration of the present means, there is no fear of the above-described inconvenience, a simple system configuration can be realized, and as a result, the system can be reduced in size and cost.

  Means 19. 19. The chemical solution supply system according to claim 18, further comprising means for calculating a discharge flow rate of the chemical solution based on a detection result by the operation amount detection means.

  As described above, since the operation amount of the movable body and the volume change of the pump chamber have a correlation, the discharge flow rate of the chemical liquid can be calculated based on the detection result by the operation amount detection means. For example, in a configuration in which the discharge flow rate is measured by a flow sensor provided in a chemical flow passage (discharge passage or the like), it is necessary to consider changes in the characteristics of the chemical liquid (changes in specific gravity, viscosity, etc.) due to temperature changes, etc. According to the above means, the discharge flow rate can be calculated corresponding to the volume change of the pump chamber without being affected by the change in the characteristics of the chemical solution.

  Means 20. The control means sets a target value of the moving speed of the movable body as the target operating amount, and sets the target value and the actual moving speed of the movable body obtained based on the detection result by the operating amount detecting means. 20. The chemical solution supply system according to means 18 or 19, wherein the pressure adjusting means is controlled based on a deviation.

  According to the means 20, since the moving speed of the movable body can be controlled as desired, an appropriate chemical solution discharge operation can be realized every time even when the chemical solution discharge operation is repeated.

  Means 21. The relationship between the operation amount of the movable body and the pump discharge amount is defined, and the control means sets the target value of the moving speed based on the flow rate command value each time using the relationship. The chemical solution supply system according to means 20.

  According to the means 21, the relationship between the operating amount of the movable body and the pump discharge amount is defined, and the target value of the moving speed of the movable body is set based on the flow rate command value each time using this relationship. In this case, the target value of the moving speed can be easily set.

  Means 22. The chemical solution supply system according to any one of means 18 to 21, wherein a plurality of the chemical solution supply pumps are provided, and these pumps are alternately operated for suction and discharge.

  In the chemical solution supply pump having the above-described configuration, the suction and discharge of the chemical solution are alternately repeated in the same pump chamber. Therefore, in the configuration using the single chemical solution supply pump, the discharge of the chemical solution is intermittently performed. In this regard, by alternately performing a suction operation and a discharge operation of a plurality of chemical liquid supply pumps as in the means 22, it becomes possible to continuously perform the discharge of the chemical liquid without interruption.

  In particular, as described above, in the configuration in which the moving speed of the movable body is feedback-controlled, the time required for discharging the chemical liquid by each pump can be made constant every time, so that the supply of the chemical liquid can be stabilized.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. In the present embodiment, a chemical supply system used in a production line for semiconductor devices or the like is embodied, and the basic configuration of the system will be described with reference to FIG.

  The chemical liquid supply system of FIG. 1 includes a chemical liquid supply pump 10 for sucking and discharging chemical liquid. In the chemical liquid supply pump 10, a bellows type partition member 12 as a volume variable member is accommodated in a pump housing 11, and a pump chamber 13 and a pressure working chamber 14 are partitioned by the bellows type partition member 12. . The bellows-type partition member 12 includes a bellows 15 that is extendable in the axial direction, and a partition plate 16 that is attached to one end of the bellows 15 (the lower end in the figure). The upper end of the figure is fixed to the annular fixing plate 17. The partition plate 16 is moved by the expansion and contraction of the bellows 15, and the volumes of the pump chamber 13 and the pressure acting chamber 14 are changed. In this case, since the total volume of the pump chamber 13 and the pressure working chamber 14 does not change regardless of the expansion and contraction of the bellows 15, for example, the volume increase amount of the pump chamber 13 corresponds to the volume reduction amount of the pressure working chamber 14 ( Of course, the same applies when the increase / decrease is reversed).

  A suction port 18 and a discharge port 19 communicating with the pump chamber 13 are formed in the pump housing 11, a suction pipe 21 is connected to the suction port 18, and a discharge pipe 22 is connected to the discharge port 19. The suction pipe 21 is provided with a suction valve 23 that is a suction-side opening / closing valve, and the suction valve 23 is opened and closed according to the energized state of the electromagnetic valve 24. Further, the discharge pipe 22 is provided with a discharge valve 25 which is a discharge side opening / closing valve, and the discharge valve 25 is opened / closed according to the energization state of the electromagnetic valve 26. For example, the suction valve 23 and the discharge valve 25 are composed of air operated valves that are opened and closed by air pressure, and the air pressure acting on the valves 23 and 25 is adjusted according to the energization state of the solenoid valves 24 and 26. Accordingly, the valves 23 and 25 are opened and closed accordingly.

  The suction pipe 21 constitutes a chemical solution supply passage for supplying a chemical solution such as a resist solution toward the pump chamber 13, and is stored in a chemical solution bottle (chemical solution storage container) (not shown) The chemical solution supplied from the chemical solution pipe is supplied to the pump chamber 13 through the suction pipe 21. Thereby, the chemical solution is filled in the pump chamber 13. The discharge pipe 22 constitutes a chemical liquid discharge passage for discharging the chemical liquid filled in the pump chamber 13, and the chemical liquid discharged from the pump chamber 13 passes through the discharge pipe 22 through a chemical liquid discharge nozzle (not shown). ). The chemical solution discharge nozzle is directed downward and is arranged so that the chemical solution is dropped at the center position of the semiconductor wafer placed on the rotating plate or the like. An appropriate amount of the chemical solution discharge nozzle is placed on the semiconductor wafer from the chemical solution discharge nozzle. The chemical solution is applied to the wafer surface by dropping the chemical solution.

  Similarly, the pump housing 11 is formed with a supply / discharge port 27 communicating with the pressure working chamber 14, and an electropneumatic regulator 28 is connected to the supply / discharge port 27. The electropneumatic regulator 28 constitutes an air pressure adjusting means for adjusting the air pressure in the pressure working chamber 14, and compressed air is supplied to the pressure working chamber 14 by a switching operation of a built-in electromagnetic switching valve. The compressed air supply state to be supplied and the atmospheric release state in which the air in the pressure working chamber 14 is discharged to the outside can be switched.

  A case body 31 is assembled to the pump housing 11, and an elongated cylindrical rod 33 is slidably inserted into a through hole 32 formed in the pump housing 11 so as to protrude toward the case body 31. Yes. That is, the rod 33 has one end protruding into the pressure acting chamber 14 and the other end protruding into the internal space surrounded by the case body 31. The partition plate 16 of the bellows-type partition member 12 is coupled to the end portion of the rod 33 on the pressure acting chamber 14 side, and the rod 33 moves in the vertical direction in the figure as the partition plate 16 moves (that is, the expansion and contraction operation of the bellows 15). Reciprocate.

  A spring receiving plate 34 is connected to the end of the rod 33 on the case body 31 side, and a compression coil spring 35 is interposed between the spring receiving plate 34 and the outer wall surface of the pump housing 11. The rod 33 is always urged upward in the figure by the urging force of the compression coil spring 35. The compression coil spring 35 corresponds to an urging means for urging the bellows type partition member 12 in a direction opposite to the air pressure in the pressure acting chamber 14.

  With the above configuration, in a state where the compressed air is not introduced into the pressure acting chamber 14 (atmospheric release state), the bellows 15 of the bellows-type partition member 12 is contracted by the biasing force of the compression coil spring 35, and the volume in the pump chamber 13 is increased. Will increase. At this time, the chemical liquid is sucked into the pump chamber 13 through the suction pipe 21 by opening the suction valve 23 and closing the discharge valve 25. In the compressed air supply state, compressed air supplied from an air pressure source (not shown) is introduced into the pressure working chamber 14 through the electropneumatic regulator 28 and the supply / discharge port 27, and the air pressure and compression in the pressure working chamber 14 are introduced. The bellows 15 is extended according to the balance with the urging force of the coil spring 35 and the volume in the pump chamber 13 is reduced. At this time, the chemical solution filled in the pump chamber 13 is discharged through the discharge pipe 22 by closing the suction valve 23 and opening the discharge valve 25.

  A position detector 36 for detecting the amount of movement of the rod 33 (that is, the amount of expansion / contraction of the bellows 15) is provided in the case body 31. In FIG. 1, reference numeral 37 is a linear bearing for holding the rod 33 so as to be able to reciprocate, and reference numeral 38 is a shaft seal for preventing air leakage from the pressure acting chamber 14.

  The controller 40 is an electronic control device mainly composed of a microcomputer composed of a CPU, various memories, and the like, and controls the state of suction and discharge of the chemical liquid by the chemical liquid supply pump 10. The controller 40 receives a suction / discharge signal, a suction speed command, and a discharge flow rate command from a management computer (not shown) that collectively manages the entire system, and a position detection signal from the position detector 36. The Then, the controller 40 controls the open / close state of the suction valve 23 and the discharge valve 25 by energizing or de-energizing the electromagnetic valves 24 and 26 based on the signal inputted each time, while controlling the electropneumatic regulator 28. A value (operating air pressure command value) is calculated, and the state of the electropneumatic regulator 28 is controlled by the command value. At this time, in particular, the controller 40 feedback-controls the state of the electropneumatic regulator 28 so that the moving speed of the partition plate 16 (rod 33) accompanying the expansion and contraction of the bellows 15 becomes the target moving speed during the suction and discharge of the chemical liquid. . In addition, the controller 40 calculates a discharge flow rate value based on the position detection signal of the position detector 36, and outputs the calculated value to a management computer or the like.

  Next, the outline of the discharge flow rate control in the controller 40 will be described with reference to FIG.

  The controller 40 calculates the moving speed of the partition plate 16 during the chemical liquid suction based on the suction speed command, and calculates the moving speed of the partition plate 16 during the chemical liquid discharge based on the discharge flow rate command. Here, at the time of calculating the movement speed at the time of discharging the chemical liquid, the movement speed is calculated based on the pump discharge characteristic representing the relationship between the movement speed and the discharge flow rate. Specifically, the movement amount of the partition plate 16 and the discharge amount of the chemical solution supply pump 10 have the relationship shown in FIG. According to FIG. 3, the pump discharge amount with respect to the movement amount of the partition plate 16 is linear, and the movement speed of the partition plate 16 is calculated using this relationship.

Here, when the discharge flow rate is Q, the bellows effective area is A, the moving distance of the partition plate 16 is X, and the moving time of the partition plate 16 is t,
Q = A * X / t
Represented as: In the above formula, “X / t” corresponds to the moving speed of the partition plate 16, and the moving speed can also be calculated by the formula.

  Further, the controller 40 selects either the moving speed during suction or the moving speed during discharge based on the suction / discharge signal. The moving speed selected at this time corresponds to the target moving speed of the partition plate 16. Then, the operating air pressure command value is calculated based on the deviation between the target moving speed of the partition plate 16 and the actual moving speed (actual moving speed) of the partition plate 16, and the electropneumatic is calculated based on the operating air pressure command value. The drive of the regulator 28 is controlled.

  On the other hand, the controller 40 calculates the actual moving speed (actual moving speed) of the partition plate 16 based on the detection result of the position detector 36 provided in the chemical solution supply pump 10. The calculated value of the actual moving speed is used not only for feedback control of the electropneumatic regulator 28 but also for each calculation of the discharge flow rate. Regarding the discharge flow rate calculation, the controller 40 converts the actual moving speed of the partition plate 16 into a discharge flow rate using the above-described pump discharge characteristics (for example, the relationship shown in FIG. 3), and outputs the result as a discharge flow rate value to a management computer or the like. To do.

  As an actual chemical supply system, a plurality of chemical supply pumps 10 are provided, and each pump 10 alternately executes a discharge operation and a supply operation, whereby a continuous chemical supply operation can be realized. FIG. 4 shows a schematic configuration of a system having two chemical solution supply pumps 10a and 10b. Each of the two chemical liquid supply pumps 10a and 10b shown in FIG. 4 has the same configuration as the chemical liquid supply pump 10 described in FIG. 1, and the components of each pump are denoted by the same reference numerals and description thereof. Is omitted. The suction pipes 21 of the chemical liquid supply pumps 10a and 10b are connected to a common suction port (chemical liquid bottle or chemical liquid pipe in a factory), and the discharge pipe 22 is connected to a common discharge port (chemical liquid discharge nozzle). Yes.

  In FIG. 4, the bellows 15 is in a contracted state in the chemical liquid supply pump 10a on the left side. In this state, the bellows 15 is then expanded to discharge the chemical liquid filled in the pump chamber 13. Further, the right side chemical liquid supply pump 10b has the bellows 15 in the extended state, and in this state, the bellows 15 contracts thereafter, and the chemical liquid is sucked into the pump chamber 13.

  The controller 40 controls the open / close state of the suction valve 23 and the discharge valve 25 based on the signals input each time as described above with the two chemical liquid supply pumps 10a and 10b as control targets, while A control command value (operating air pressure command value) is calculated, and the state of the electropneumatic regulator 28 is controlled by the command value.

  FIG. 5 is a time chart for explaining a chemical solution discharge operation in the chemical solution supply system. In FIG. 5, the continuous supply of chemical liquid to the semiconductor wafer is realized by the two chemical liquid supply pumps 10a and 10b alternately repeating the suction operation and the discharge operation. In the description of FIG. 5, for convenience, one chemical supply pump 10 is referred to as a pump (A) and the other chemical supply pump 10 is referred to as a pump (B), and (A) and (B) are also used for the suction valve and the discharge valve. To distinguish.

  Prior to timing t1, the pump (A) is in the state of the chemical supply pump 10a in FIG. 4, the pump (B) is in the state of the chemical supply pump 10b in FIG. 4, and the suction valve and the discharge valve are both closed. Yes. Then, after the timing t1, the chemical liquid is sucked and discharged by each pump as the START signal rises.

  That is, on the pump (A) side, after the discharge valve (A) is opened at timing t1, the bellows 15 is extended with the increase in air pressure by the electropneumatic regulator 28, and the chemical solution is discharged (timing t2 to t6). In parallel with the discharge of the chemical solution by the pump (A), on the pump (B) side, the suction valve (B) is opened at timings t3 to t4 to suck the chemical solution. Then, the discharge valve (B) is opened at timing t5 after completion of the chemical liquid suction. At timing t6, the bellows 15 expands with the increase in air pressure by the electropneumatic regulator 28 on the pump (B) side, and the chemical solution is discharged (timing t6 to t7). Thereafter, suction / discharge operations are alternately performed by the pumps (A) and (B), and the chemical liquid is continuously discharged from the tip of the chemical liquid discharge nozzle.

  In this case, the chemical liquid discharge period TA by the pump (A) and the chemical liquid discharge period TB by the pump (B) are set continuously, and the chemical liquid is continuously discharged without interruption. Further, since the discharge speed of the chemical liquid is controlled to be constant, the discharge periods TA and TB are the same, and the chemical liquid can be stably supplied.

  According to the embodiment described above in detail, the following excellent effects can be obtained.

  Since the moving speed of the partition plate 16 constituting the bellows-type partition member 12 is feedback controlled at the time of suction or discharge of the chemical liquid, the volume change of the pump chamber 13 can be controlled as desired. Thereby, it becomes possible to control the suction flow rate or the discharge flow rate of the chemical liquid to a desired flow rate with high accuracy. Further, since the chemical solution supply pump 10 sucks or discharges the chemical solution using the air pressure adjusted by the electropneumatic regulator 28 as a drive source, the adverse effect due to heat occurs unlike the electric system that controls the flow rate by the electric motor. There is no fear, and even a chemical solution requiring temperature control can be suitably used. Further, the configuration of the pump drive system can be simplified as compared with the configuration of the electric actuator.

  The position detector 36 detects the amount of movement of the rod 33 connected to the bellows-type partition member 12 (partition plate 16), and the detected amount of movement of the rod 33 (the amount of movement of the partition plate 16 and the amount of expansion and contraction of the bellows 15) are also detected. (Consent) was used as a feedback parameter, so a flow rate sensor, variable throttle, etc. were provided in the chemical solution discharge passage, and compared with other configurations using the result as a feedback parameter, it was caused by liquid accumulation at the installation site of the sensor, throttle, etc. Inconveniences such as deterioration of the chemical solution and the necessity of special processing to prevent corrosion of the sensor and the like by the chemical solution are eliminated. Therefore, a simple system configuration can be realized, and as a result, the size and cost of the system can be reduced.

  Further, since the discharge flow rate of the chemical solution is calculated based on the detection result of the position detector 36, the discharge flow rate can be calculated accurately without being affected by the change in the characteristics of the chemical solution.

  Since the position detector 36 is provided in the case body 31 isolated from the pump chamber 13, there is no possibility that the position detector 36 is exposed to the chemical solution. Therefore, it is not necessary to take measures for preventing corrosion due to chemicals for the position detector and its accessory parts, and a simple and inexpensive system can be realized.

  Since a plurality of chemical liquid supply pumps 10 are provided and each of these pumps 10 is configured to alternately perform a suction operation and a discharge operation, the chemical liquid discharge can be continuously performed without interruption. Further, as described above, since the moving speed of the bellows type partitioning member 12 (partition plate 16) is controlled by feedback control, the time required for discharging the chemical solution by each pump can be made constant every time, so that the stable supply of the chemical solution is possible. Is possible.

(Second Embodiment)
Next, a second embodiment will be described focusing on differences from the first embodiment. In the present embodiment, a diaphragm type chemical solution supply pump 50 is used, and FIG. 6 shows a schematic configuration of the chemical solution supply pump 50 and its periphery.

  In FIG. 6, the chemical solution supply pump 50 has bodies 51 and 52 that are divided into upper and lower parts, and concave portions 51 a and 52 a are formed on the opposing surfaces of the bodies 51 and 52, respectively. A diaphragm 53 made of a substantially circular flexible film is interposed between the bodies 51 and 52, and a peripheral portion 53 a of the diaphragm 53 is sandwiched between the bodies 51 and 52. A central thick part 53 b is provided at the center of the diaphragm 53. In this case, the space formed between the recess 51 a on the body 51 side and the diaphragm 53 is the pump chamber 55, and the space formed between the recess 52 a on the body 52 side and the diaphragm 53 is the pressure action chamber 56. Yes.

  A suction port 58 and a discharge port 59 communicating with the pump chamber 55 are formed in the body 51, a suction pipe 61 is connected to the suction port 58, and a discharge pipe 62 is connected to the discharge port 59. The suction pipe 61 is provided with a suction valve 63 that is a suction-side opening / closing valve, and the suction valve 63 is opened / closed according to the energization state of the electromagnetic valve 64. The discharge pipe 62 is provided with a discharge valve 65 that is a discharge-side opening / closing valve, and the discharge valve 65 is opened / closed according to the energization state of the electromagnetic valve 66. For example, the suction valve 63 and the discharge valve 65 are air operated valves that are opened and closed by air pressure, and the air pressure acting on the valves 63 and 65 is adjusted according to the energization state of the electromagnetic valves 64 and 66. Accordingly, the valves 63 and 65 are opened and closed accordingly.

  The suction pipe 61 constitutes a chemical solution supply passage for supplying a chemical solution such as a resist solution toward the pump chamber 55. The suction pipe 61 stores a chemical solution stored in a chemical solution bottle (chemical solution storage container) (not shown) or a factory solution. The chemical solution supplied from the chemical solution pipe is supplied to the pump chamber 55 through the suction pipe 61. Thereby, the chemical solution is filled in the pump chamber 55. The discharge pipe 62 constitutes a chemical liquid discharge passage for discharging the chemical liquid filled in the pump chamber 55, and the chemical liquid discharged from the pump chamber 55 passes through the discharge pipe 62 through a chemical liquid discharge nozzle (not shown). ).

  The other body 52 has a supply / discharge port 68 communicating with the pressure acting chamber 56, and an electropneumatic regulator 69 is connected to the supply / discharge port 68. The electropneumatic regulator 69 constitutes an air pressure adjusting means for adjusting the air pressure in the pressure working chamber 56, and compressed air is supplied to the pressure working chamber 56 by a switching operation of a built-in electromagnetic switching valve. The compressed air supply state to be supplied and the atmospheric release state in which the air in the pressure working chamber 56 is discharged to the outside can be switched.

  A case body 71 is assembled to the body 52, and an elongated cylindrical rod 73 is slidably inserted into a through hole 72 formed in the body 52 so as to protrude toward the case body 71. That is, the rod 73 has one end protruding into the pressure acting chamber 56 and the other end protruding into the internal space surrounded by the case body 71. The central thick portion 53b of the diaphragm 53 is coupled to the end of the rod 73 on the pressure acting chamber 56 side, and the rod 73 reciprocates in the vertical direction in the figure as the diaphragm 53 is deformed.

  A spring receiving plate 74 is connected to the end of the rod 73 on the case body 71 side, and a compression coil spring 75 is interposed between the spring receiving plate 74 and the outer wall surface of the body 52. The rod 73 is always biased upward in the figure by the biasing force of the compression coil spring 75. The compression coil spring 75 corresponds to an urging means for urging the diaphragm 53 in a direction opposite to the air pressure in the pressure acting chamber 56.

  With the above configuration, in a state where compressed air is not introduced into the pressure acting chamber 56 (atmospheric release state), the diaphragm 53 is bent and deformed upward by the urging force of the compression coil spring 75, and the volume in the pump chamber 55 increases. . At this time, the chemical solution is sucked into the pump chamber 55 through the suction pipe 61 by opening the suction valve 63 and closing the discharge valve 65. Further, in the compressed air supply state, compressed air supplied from an air pressure source (not shown) is introduced into the pressure action chamber 56 through the electropneumatic regulator 69 and the supply / discharge port 68, and the air pressure in the pressure action chamber 56 and the compression are compressed. In accordance with the balance with the urging force of the coil spring 75, the diaphragm 53 is bent and deformed downward in the figure, and the volume in the pump chamber 55 is reduced. At this time, the chemical solution filled in the pump chamber 55 is discharged through the discharge pipe 62 by closing the suction valve 63 and opening the discharge valve 65.

  In the case body 71, a position detector 76 for detecting the amount of movement of the rod 73 (that is, the amount of deformation of the diaphragm 53) is provided. In FIG. 6, reference numeral 77 is a linear bearing for holding the rod 73 so as to be able to reciprocate, and reference numeral 78 is a shaft seal for preventing air leakage from the pressure acting chamber 56.

  The controller 80 is an electronic control device mainly composed of a microcomputer composed of a CPU, various memories, and the like, and controls the state of suction and discharge of the chemical liquid by the chemical liquid supply pump 50. The controller 80 receives a suction / discharge signal, a suction speed command, and a discharge flow rate command from a management computer (not shown) that manages the entire system, and a position detection signal from the position detector 76. The Then, the controller 80 controls the open / close state of the suction valve 63 and the discharge valve 65 by energizing or de-energizing the electromagnetic valves 64 and 66 based on the signal input each time, while controlling the electropneumatic regulator 69. A value (operation air pressure command value) is calculated, and the state of the electropneumatic regulator 69 is controlled by the command value. At this time, in particular, the controller 80 feedback-controls the state of the electropneumatic regulator 69 so that the deformation speed of the diaphragm 53 becomes a target speed at the time of sucking and discharging the chemical liquid. In addition, the controller 80 calculates a discharge flow rate value based on the position detection signal of the position detector 76, and outputs the calculated value to a management computer or the like.

  By the way, the diaphragm type chemical solution supply pump 50 as described above has an advantage that the liquid pool is less than that of the bellows type chemical solution supply pump, but the chemical solution discharge amount with respect to the deformation amount of the diaphragm 53 becomes non-linear. There is a concern that the amount control becomes difficult. FIG. 7 is a diagram showing the relationship between the amount of deformation of the diaphragm and the discharge amount of the chemical solution. According to FIG. 7, it can be seen that the diaphragm characteristic is nonlinear with respect to the ideal linear characteristic.

  Therefore, in the present embodiment, the relationship between the diaphragm deformation amount and the pump discharge amount is linearized for each section divided into a plurality within the deformation range (full stroke range) of the diaphragm 53, and the linearized relationship is used. Thus, the state of the electropneumatic regulator 69 is controlled. For example, as shown in FIG. 7, the deformation range (X0 to X5) of the diaphragm 53 is equally divided into five sections, and a linear characteristic is added to each section. When the chemical solution is sucked / discharged by the chemical solution supply pump 50, the state of the electropneumatic regulator 69 is controlled by properly using the linear characteristics of each section according to the deformation amount of the diaphragm 53 each time. It should be noted that the data relating to the linear characteristic of each section is preferably acquired by measurement or the like and stored in advance in a memory in the controller 80.

  Here, a linearization method in each section will be described.

  When the deformation range of the diaphragm 53 is divided into five equal parts, the diaphragm deformation amounts serving as the boundary points of the respective sections are X0, X1, X2, X3, X4, and X5, of which the discharge amount q1 corresponding to the diaphragm deformation amounts X1 to X5. , Q2, q3, q4, q5 are measured (the discharge amount in the case of the diaphragm deformation amount X0 is 0 and measurement is not required). Then, linearization is performed for each section by linear interpolation based on the diaphragm deformation amount and the discharge amount at the boundary point of each section. At this time, the conversion formula from the diaphragm deformation amount X to the discharge amount q is defined as shown in FIG. 8A according to the diaphragm deformation amount. Further, the conversion formula from the diaphragm deformation speed X / t to the discharge flow rate Q is defined as shown in FIG. 8B according to the diaphragm deformation amount.

  The characteristics linearized for each section as described above are the calculation of the deformation speed of the diaphragm 53 (calculation of the target value of the deformation speed) and the detected value of the amount of deformation of the diaphragm (the detection result of the position detector 76). ) Based on the actual discharge flow rate value. That is, in the arithmetic logic described with reference to FIG. 2, the linear characteristic for each section is used when calculating the movement speed during ejection. Further, the linear characteristic for each section is used when converting the movement speed calculated based on the position detection result into the discharge flow rate.

  FIG. 9 shows a processing flow by the controller 80 relating to movement speed calculation, and FIG. 10 shows a processing flow by the controller 80 relating to actual discharge flow rate calculation.

In FIG. 9, the discharge flow rate command value Qc is taken in and the diaphragm deformation amount X is measured (steps S11 and S12). Thereafter, it is determined in which of the sections the diaphragm deformation amount X is present (steps S13 to S17), and a conversion formula to be applied this time is determined according to the determination result (steps S18 to S22). In this case, if X <X1, the conversion equation (1) is obtained, if X1 ≦ X <X2, the conversion equation (2) is obtained, if X2 ≦ X <X3, the transformation equation (3) is obtained, and X3 ≦ X < If X4, the conversion formula (4) is applied, and if X ≧ X4, the conversion formula (5) is applied.
X / t = (X1-X0) / q1 * Qc (1)
X / t = (X2-X1) / (q2-q1) * Qc (2)
X / t = (X3-X2) / (q3-q2) * Qc (3)
X / t = (X4-X3) / (q4-q3) * Qc (4)
X / t = (X5-X4) / (q5-q4) * Qc (5)
After determining the conversion equation to be applied this time as described above, the diaphragm deformation speed X / t is calculated using the determined conversion equation, and the discharge amount control is performed based on the X / t value (step S23). ).

In FIG. 10, the diaphragm deformation amount X is measured and the diaphragm deformation speed X / t is calculated (steps S31 and S32). Thereafter, it is determined in which of the sections the diaphragm deformation amount X is present (steps S33 to S37), and a conversion formula to be applied this time is determined according to the determination result (steps S38 to S42). In this case, if X <X1, the conversion equation (6) is obtained, if X1 ≦ X <X2, the conversion equation (7) is obtained, if X2 ≦ X <X3, the transformation equation (8) is obtained, and X3 ≦ X < If X4, the conversion equation (9) is applied, and if X ≧ X4, the conversion equation (10) is applied.
Q = q1 / (X1-X0) * X / t (6)
Q = (q2-q1) / (X2-X1) * X / t (7)
Q = (q3-q2) / (X3-X2) * X / t (8)
Q = (q4-q3) / (X4-X3) * X / t (9)
Q = (q5-q4) / (X5-X4) * X / t (10)
After determining the conversion formula to be applied this time as described above, the discharge flow rate value Q is calculated using the determined conversion formula (step S43).

  Although the measurement methods of the discharge amounts q1 to q5 are arbitrary, for example, the following methods (1) and (2) are conceivable.

  (1) The diaphragm deformation amount is changed within the range of X0 to X5, and the discharge amount when the deformation amount is X1, X2, X3, X4, and X5 is measured with a measuring instrument such as a graduated cylinder. Specifically, first, with the suction valve 63 opened and the discharge valve 65 closed, the diaphragm 53 is deformed to the suction side to suck the chemical into the pump chamber 55. After completion of the chemical liquid suction, the suction valve 63 is closed, the discharge valve 65 is opened, and the apparatus is on standby. This state is diaphragm deformation amount = X0. Thereafter, the diaphragm 53 is slowly deformed to the discharge side until the deformation amount X1 is reached, and the deformation operation is temporarily stopped at the deformation amount X1. The discharge amount at this time is measured with a measuring cylinder or the like and recorded as the discharge amount q1. Thereafter, when the diaphragm deformation amounts are X2, X3, X4, and X5, the discharge amounts are similarly measured and recorded as discharge amounts q2, q3, q4, and q5. And each said data is input into the controller 80, and is memorize | stored in memory.

  (2) While the diaphragm deformation amount is feedback controlled by the controller 80, the discharge amount of the chemical solution during the control is sequentially measured and stored in the memory. In such a case, a discharge amount measuring device is connected to the discharge pipe 62 (especially downstream of the discharge valve 65) of the chemical liquid supply pump 50, and the discharge amount during the discharge operation of the pump 50 is measured by the discharge amount measuring device. Then, the measurement result (measurement signal) of the discharge amount measuring device is sequentially input to the controller 80. As the discharge amount measuring device, for example, the stroke amount of the plunger (plunger position) is made variable according to the amount of the chemical solution introduced into the chemical solution introduction chamber formed inside the measuring device, and the stroke amount of the plunger is detected. A so-called cylinder-type discharge amount measuring device that measures the discharge amount is used.

  The discharge amount measurement procedure in the case of (2) will be described more specifically with reference to the time chart of FIG.

  In FIG. 11, when an ON output of a measurement start signal is input to the controller 80, a series of discharge amount measurement processing is started. First, the pump chamber 55 of the chemical solution supply pump 50 and the chemical solution introduction chamber of the discharge amount measuring device are started. A chemical solution is supplied, and each of the chambers is filled with the chemical solution. That is, the opening / closing of the suction valve 63 and the discharge valve 65 and the diaphragm deformation amount are controlled as shown in the drawing so that the operations are performed in the order of suction → discharge → suction. The measurement valve is an on-off valve provided on the outlet side of the chemical solution introduction chamber of the discharge amount measuring device, and is opened during a period in which suction and discharge are performed once, and then closed.

  Then, after the timing t10, the diaphragm 53 is deformed to the discharge side at a constant speed, and accordingly, the discharge flow rate with respect to each diaphragm deformation amount (diaphragm position) of X1 to X5 is sequentially measured. At this time, first, at a timing t11, the discharge amount q1 at the diaphragm deformation amount = X1 is measured, and the q1 value is stored in the memory in the controller 80. After that, similarly, at timings t12, t13, t14, and 15, the diaphragm deformation amounts = discharge amounts q2, q3, q4, and q5 at X2, X3, X4, and X5 are measured, and these values are stored in the memory in the controller 80. Is remembered.

  As described in the first embodiment, a plurality of chemical solution supply pumps 50 may be provided, and these pumps 50 may be alternately configured to perform a suction operation and a discharge operation. Thereby, it becomes possible to carry out continuously without interrupting the discharge of the chemical liquid. In addition, the time required for discharging the chemical solution by each pump is made constant every time, and the stable supply of the chemical solution can be realized.

  In the second embodiment described in detail above, the relationship between the diaphragm deformation amount and the pump discharge amount is linearized for each of the sections divided into a plurality within the deformation range of the diaphragm 53, and the discharge amount is calculated using the linearized relationship. Since the control is performed, the suction flow rate or the discharge flow rate of the chemical solution can be controlled with high accuracy even in the diaphragm type chemical solution supply pump 50 in which the deformation amount and the discharge amount are not linear.

  The chemical supply pump using a diaphragm as the variable volume member has an advantage that the liquid pool is less than that of the chemical supply pump using a bellows. Therefore, it is possible to realize a chemical solution supply system that has a small amount of liquid pool and enables highly accurate chemical solution flow rate control.

(Third embodiment)
In the third embodiment, another configuration will be described as a diaphragm type chemical liquid supply pump.

  In FIG. 12, the chemical solution supply pump 100 has bodies 101 and 102 that are divided into left and right parts, and recesses 101 a and 102 a are formed on the opposing surfaces of the bodies 101 and 102. A diaphragm 103 made of a substantially circular flexible film is interposed between the bodies 101 and 102, and a peripheral edge 103 a of the diaphragm 103 is held between the bodies 101 and 102. In this case, the space formed between the recess 101a on the body 101 side and the diaphragm 103 is the pump chamber 105, and the space formed between the recess 102a on the body 102 side and the diaphragm 103 is the diaphragm operation chamber 106. Yes.

  A suction port 108 and a discharge port 109 communicating with the pump chamber 105 are formed in the body 101, a suction pipe 111 is connected to the suction port 108, and a discharge pipe 112 is connected to the discharge port 109. The suction pipe 111 is provided with a suction valve 113 that is a suction side opening / closing valve, and the suction valve 113 is opened and closed according to the energization state of the electromagnetic valve 114. Further, the discharge pipe 112 is provided with a discharge valve 115 which is a discharge side opening / closing valve, and the discharge valve 115 is opened / closed according to the energization state of the electromagnetic valve 116. For example, the suction valve 113 and the discharge valve 115 are air operated valves that are opened and closed by air pressure, and the air pressure acting on the valves 113 and 115 is adjusted according to the energization state of the electromagnetic valves 114 and 116. Accordingly, the valves 113 and 115 are opened and closed accordingly.

  The suction pipe 111 constitutes a chemical solution supply passage for supplying a chemical solution such as a resist solution toward the pump chamber 105, and is stored in a chemical solution bottle (chemical solution storage container) (not shown) The chemical liquid supplied from the chemical liquid pipe is supplied to the pump chamber 105 through the suction pipe 111. Thereby, the chemical solution is filled in the pump chamber 105. The discharge pipe 112 constitutes a chemical liquid discharge passage for discharging the chemical liquid filled in the pump chamber 105, and the chemical liquid discharged from the pump chamber 105 passes through the discharge pipe 112 through a chemical liquid discharge nozzle (not shown). ).

  The other body 102 is formed with a communication passage 117 that communicates with the diaphragm operation chamber 106, and this communication passage 117 communicates with the cylinder chamber 118. The cylinder chamber 118 forms a two-stage cylindrical space having different diameters, and a plunger 119 is slidably accommodated in the cylinder chamber 118. Plunger 119 has sliding portions 119a and 119b at the tip portion and the intermediate portion, and an air release chamber in which a portion is open to the atmosphere on one side (the lower side in the figure) across sliding portion 119b. 121 is formed, and a pneumatic operation chamber 122 is formed on the other side (the lower side in the figure). A seal member is assembled to the outer peripheral portion of each sliding portion 119a, 119b. Further, the distal end side of the plunger 119 (below the sliding portion 119a) is a fluid chamber 123, and an incompressible fluid (for example, in the space from the fluid chamber 123 to the communication path 117 and the diaphragm operation chamber 106). Silicone oil) is filled. Further, the upper end portion of the plunger 119 in the figure protrudes above the body 102 through the through hole 124.

  A supply / discharge port 125 communicating with the pneumatic operation chamber 122 is formed in the body 102, and an electropneumatic regulator 127 is connected to the supply / discharge port 125. The electropneumatic regulator 127 constitutes an air pressure adjusting means for adjusting the air pressure in the pneumatic operation chamber 122 and is compressed into the pneumatic operation chamber 122 by a switching operation of a built-in electromagnetic switching valve. A compressed air supply state in which air is supplied and an atmospheric release state in which the air in the pneumatic operation chamber 122 is discharged to the outside can be switched.

  A case body 131 is assembled to the body 102. A spring receiving plate 132 is connected to the tip of the plunger 119 in the case body 131, and a compression coil spring 133 is interposed between the spring receiving plate 132 and the outer wall surface of the body 102. The plunger 119 is always biased upward in the figure by the biasing force of the compression coil spring 133.

  With the above configuration, in a state where compressed air is not introduced into the pneumatic operation chamber 122 (atmospheric release state), the plunger 119 is held in a state where it is lifted upward in the drawing by the urging force of the compression coil spring 133. As a result, the incompressible fluid moves from the diaphragm operation chamber 106 to the fluid chamber 123, the diaphragm 103 is bent and deformed to the right in the figure, and the volume in the pump chamber 105 increases. At this time, the chemical solution is sucked into the pump chamber 105 through the suction pipe 111 by opening the suction valve 113 and closing the discharge valve 115.

  In the compressed air supply state, compressed air supplied from an air pressure source (not shown) is introduced into the pneumatic operation chamber 122 through the electropneumatic regulator 127 and the supply / exhaust port 125, and the air pressure in the pneumatic operation chamber 122 is increased. The plunger 119 moves downward in the figure according to the balance between the biasing force of the compression coil spring 133 and the biasing force of the compression coil spring 133. As a result, the incompressible fluid moves from the fluid chamber 123 to the diaphragm operation chamber 106, and the diaphragm 103 is bent and deformed to the left in the figure, so that the volume in the pump chamber 105 is reduced. At this time, the chemical solution filled in the pump chamber 105 is discharged through the discharge pipe 112 by closing the suction valve 113 and opening the discharge valve 115.

  A position detector 135 for detecting the amount of movement of the plunger 119 is provided in the case body 131. In FIG. 12, reference numeral 137 is a linear bearing for holding the plunger 119 so as to be able to reciprocate, and reference numeral 138 is a shaft seal for preventing air leakage from the pneumatic operation chamber 122.

  The controller 140 is an electronic control unit mainly composed of a microcomputer composed of a CPU, various memories, and the like, and controls the state of suction and discharge of the chemical liquid by the chemical liquid supply pump 100. The controller 140 receives a suction / discharge signal, a suction speed command, and a discharge flow rate command from a management computer (not shown) that manages and manages the entire system, and a position detection signal from the position detector 135. The Then, the controller 140 controls the open / close state of the suction valve 113 and the discharge valve 115 by energizing or de-energizing the electromagnetic valves 114 and 116 based on the input signal each time, while controlling the electropneumatic regulator 127. A value (operating air pressure command value) is calculated, and the state of the electropneumatic regulator 127 is controlled by the command value. At this time, in particular, the controller 140 feedback-controls the state of the electropneumatic regulator 127 so that the moving speed of the plunger 119 becomes a target speed at the time of sucking and discharging the chemical liquid. In addition, the controller 140 calculates a discharge flow rate value based on the position detection signal of the position detector 135 and outputs the calculated value to a management computer or the like.

  The content of the arithmetic processing by the controller 140 is generally similar to the control logic of FIG. 2, and will be briefly described here.

  The controller 140 calculates the moving speed of the plunger 119 during chemical liquid suction based on the suction speed command, and calculates the moving speed of the plunger 119 during chemical liquid discharge based on the discharge flow rate command. Here, at the time of calculating the movement speed at the time of discharging the chemical liquid, the movement speed is calculated based on the pump discharge characteristic representing the relationship between the movement speed and the discharge flow rate. That is, the movement amount of the plunger 119 and the pump discharge flow rate have a correlation, and the movement speed of the plunger 119 is calculated from the discharge flow rate command value using a predetermined linear characteristic. Then, the operating air pressure command value is calculated based on the deviation between the target moving speed of the plunger 119 and the actual moving speed (actual moving speed), and the electropneumatic regulator 127 is driven based on the operating air pressure command value. Control.

  On the other hand, the controller 140 calculates the actual moving speed (actual moving speed) of the plunger 119 based on the detection result of the position detector 135. The calculated value of the actual moving speed is used for the feedback control of the electropneumatic regulator 127 and is used for the calculation of the discharge flow rate each time. Regarding the discharge flow rate calculation, the controller 140 converts the actual movement speed of the plunger 119 into a discharge flow rate using the correlation (linear characteristic) between the movement amount of the plunger 119 and the pump discharge flow rate, and manages the result as a discharge flow rate value. Output to computer etc.

  In the chemical liquid supply pump 100 having the above-described configuration, the air pressure in the pneumatic operation chamber 122 is adjusted by the electropneumatic regulator 127, and the plunger 119 moves up or down in the figure by the pressure adjustment. When the plunger 119 moves, the volume of the fluid chamber 123 changes linearly with respect to the movement amount, and the volume of the diaphragm operation chamber 106 changes correspondingly. The diaphragm 103 is bent and deformed according to the volume change of the diaphragm operation chamber 106, and the suction or discharge of the chemical solution is performed based on the volume change of the pump chamber 105 accompanying the diaphragm deformation. At this time, the diaphragm operation chamber 106 and the fluid chamber 123 are filled with an incompressible fluid, and the volume change of the fluid chamber 123 coincides with the volume change of the diaphragm operation chamber 106 (one increase is a decrease of the other). Minutes). Further, the volume change of the fluid chamber 123 with respect to the movement amount of the plunger 119 is linear. Therefore, it becomes possible to control the flow rate at the time of suction or discharge of the chemical liquid with high accuracy based on the movement amount of the plunger 119.

  Further, in the chemical solution supply pump 100, the effective sectional area of the plunger 119 is smaller than the effective sectional area of the diaphragm 103. Thereby, when the diaphragm 103 is bent and deformed, the plunger movement amount becomes larger than the diaphragm deformation amount. Therefore, the amount of bending deformation of the diaphragm 103 can be finely controlled. At this time, if the diaphragm effective cross-sectional area is Ad and the diaphragm deformation amount Xd, the discharge amount V accompanying the diaphragm deformation is V≈Ad * Xd. On the other hand, if the effective sectional area of the plunger 119 is A and the plunger movement amount is X, the discharge amount V accompanying the plunger movement is V≈A * X. Therefore, X = Ad / A * Xd, and the plunger movement amount X is amplified with the amplification factor Ad / A with respect to the diaphragm deformation amount Xd.

  The plunger 119 has two sliding portions 119a and 119b that are different in size. The area facing the fluid chamber 123 is relatively small, and the area facing the pneumatic operation chamber 122 is relatively small. It has a large shape. At this time, since the pressure receiving area on the pneumatic operation chamber 122 side in the plunger 119 is relatively large, a sufficient force can be applied when the plunger 119 is moved by air pressure. As a result, the responsiveness of the plunger 119 is improved, and as a result, the deformation speed of the diaphragm 103 (e.g., the discharge amount of the chemical liquid) can be arbitrarily controlled.

  As described in the first embodiment, a plurality of chemical solution supply pumps 100 may be provided, and the pumps 100 may alternately perform a suction operation and a discharge operation. Thereby, it becomes possible to carry out continuously without interrupting the discharge of the chemical liquid. In addition, the time required for discharging the chemical solution by each pump is made constant every time, and the stable supply of the chemical solution can be realized.

  In the third embodiment described in detail above, the discharge amount control is performed using the plunger movement amount as a feedback parameter instead of the diaphragm deformation amount. In this case, the pump discharge amount with respect to the diaphragm deformation amount is not linear, but the pump discharge amount with respect to the plunger movement amount is linear, so that the flow rate during the suction or discharge of the chemical liquid can be controlled with high accuracy. Further, since the chemical liquid supply pump 100 sucks or discharges the chemical liquid using the air pressure adjusted by the electropneumatic regulator 127 as a driving source, unlike the electric system that controls the flow rate by the electric motor, a harmful effect due to heat occurs. There is no fear, and even a chemical solution requiring temperature control can be suitably used. Further, the configuration of the pump drive system can be simplified as compared with the configuration of the electric actuator.

  Also, compared to other configurations where the flow rate sensor, variable throttle, etc. are provided in the chemical solution discharge passage and the result is used as a feedback parameter, the chemical solution deteriorates due to liquid pooling at the installation site of the sensor, throttle, etc. Or the inconvenience that special processing is forced to prevent corrosion of the sensor or the like by the chemical solution. Therefore, a simple system configuration can be realized, and as a result, the size and cost of the system can be reduced.

  Further, since the discharge flow rate of the chemical solution is calculated based on the detection result of the position detector 135, the discharge flow rate can be calculated with high accuracy without being affected by the change in the characteristics of the chemical solution.

  In addition, this invention is not limited to the content of description of the said embodiment, For example, you may implement as follows.

  The pressure in the pump chamber is calculated based on the position detection result by the position detector (result of detecting the operation amount of bellows, diaphragm, etc.), and the clogging of the chemical discharge passage is determined based on the calculated pressure in the pump chamber. May be. This will be described with respect to the configuration (FIG. 1) described in the first embodiment.

In FIG. 1, the air pressure in the pressure acting chamber 14 acts on the bellows type partition member 12 from one side (upper side in the figure) and is attached by the compression coil spring 35 from the other side (lower side in the figure). The force and the pressure in the pump chamber 13 act. And the bellows type partition member 12 is controlled to the position where those forces balanced. In this case, the force received by the bellows partition member 12 by the gas pressure in the pressure acting chamber 14 is Fs, the force received by the bellows partition member 12 by the compression coil spring 35 is Fb, and the pressure in the pump chamber 13 is used by the bellows partition member 12. If the force received by Fp is
Fs = Fb + Fp
The relationship is established. Here, Fb (the force received by the bellows type partition member 12 by the compression coil spring 35) correlates with the operation amount of the bellows type partition member 12, and the spring constant is k, and the bellows when the suction is complete (when fully contracted). If the position is Xa and the bellows position in operation is X,
Fb = k * (Xa + X)
Given in.

Fs (the force received by the bellows type partition member 12 due to the air pressure in the pressure working chamber 14) can be calculated from the air pressure in the pressure working chamber 14, the effective area of the bellows is A, and the air pressure in the pressure working chamber 14 is Ps. Then,
Fs = A * Ps
Given in.

Further, Fp (the force received by the bellows-type partition member 12 due to the pressure in the pump chamber 13) is expressed as follows.
Fp = A * P
Given in.
In this case, since Fp = Fs−Fb, the pump chamber pressure P is
P = Ps−k / A * (Xa + X)
It becomes. Here, k, A, and Xa are fixed values, and the pump chamber pressure P can be calculated by measuring the air pressure Ps in the pressure working chamber 14 and the bellows position X during operation.

  The pump chamber pressure P can be basically calculated from design dimensional data or the like, but considering individual differences, it is preferable to measure the characteristics for each solid and store the measurement data in the controller. Thereby, the pump chamber pressure P can be calculated more accurately.

Here, when the pressure loss on the discharge side is S, the discharge flow rate Q is roughly
Q = α / S * √P
(Α is a constant). Therefore, when the pressure loss S increases, the pump chamber pressure P increases. In other words, when clogging (filter clogging or the like) occurs in the discharge pipe, the pressure in the pump chamber increases due to pressure loss even if the chemical discharge amount is the same. Therefore, occurrence of clogging can be determined.

  For example, it is preferable to determine in advance a pressure determination value when performing discharge amount control at a predetermined discharge flow rate, and to determine that clogging has occurred when the pump chamber pressure P becomes greater than the pressure determination value. The pressure determination value may be determined based on an initial (new) pressure value. When clogging occurs, for example, a sound or a lamp is notified, and the operator replaces the filter or the like in the discharge pipe accordingly. By performing the clogging determination, it is possible to eliminate a process defect caused by the clogging.

  Further, in the configuration for calculating the pump chamber pressure P as described above, a pressure sensor for detecting the pump chamber pressure P is not necessary. As a result, there is no sensor device or the like that is directly exposed to the chemical solution, so that no countermeasure against corrosion due to the chemical solution is imposed, and the configuration can be simplified and the cost can be reduced.

  Besides performing the clogging determination based on the calculated value of the pump chamber pressure P, it is also possible to perform feedback control of the pump chamber pressure based on the calculated value of the pump chamber pressure P.

  A suck back function may be added to prevent dripping at the end of discharge of the chemical liquid. FIG. 13 is a time chart for explaining the suck back operation.

  In FIG. 13, when the chemical solution is discharged, the suction valve is closed and the discharge valve is opened, and the chemical solution is discharged from the pump chamber in accordance with the operation of the variable volume member. After the discharge of the chemical liquid, the state where the suction valve is closed and the discharge valve is opened is temporarily continued, and the operation of the volume variable member such as the bellows is reversed and the suction of the chemical liquid is started. The At this time, suck back is performed by the suction operation of the chemical liquid in a state where the suction valve is closed and the discharge valve is opened. TS in the figure is a suck back operation period. Thereby, it is possible to prevent liquid dripping at the nozzle below the medicine droplet. In the above configuration, the on / off valve for suck back is not necessary, and thus the configuration can be simplified.

  The suck back operation period (TS in FIG. 13) and the suction speed during suck back may be variably controlled. As a result, the suck back operation of the chemical solution can be arbitrarily controlled, and the suck back amount can be controlled as desired.

  In the above embodiment, when the bellows type chemical supply pump is used, it has been explained that the pump discharge amount is linear with respect to the bellows expansion / contraction amount, but strictly speaking, nonlinear characteristics are included in the expansion / contraction range of the bellows. It can also be considered. Therefore, the relationship between the bellows expansion / contraction amount and the pump discharge amount may be linearized for each section divided into a plurality within the expansion / contraction range of the bellows, and the discharge amount control may be performed using the linearized relationship. Thereby, the control accuracy of the suction flow rate or the discharge flow rate of the chemical liquid is improved. Note that the method described in the second embodiment is appropriately used as a method of performing linearization for each section.

  In each of the above-described embodiments, when the air pressure in the pressure working chamber is reduced, the electropneumatic regulator is opened to the atmosphere, but this is changed. For example, a vacuum source is connected to the electro-pneumatic regulator, and the pressure working chamber is set to a negative pressure by the operation of the vacuum source. The operation amount of the bellows, the diaphragm and the like can be arbitrarily controlled by the operation of the air pressure. In this case, the compression coil spring provided in the case body can be eliminated.

  In the chemical solution supply pump 100 described in the third embodiment, the plunger 119 is used as a movable body that linearly changes the volume of the fluid chamber 123 with respect to the operation amount. It is also possible to use a bellows.

  In each of the above-described embodiments, as a specific example of a chemical solution supply system including a plurality of chemical solution supply pumps, a combination of a plurality of chemical solution supply pumps is used to connect the pumps by piping or the like. You may make it employ | adopt the pump unit with which the chemical | medical solution supply pump was integrated. Thereby, reduction of piping etc. and space saving can be achieved.

It is a block diagram which shows the outline of the chemical | medical solution supply system in embodiment of invention. It is a figure which shows the outline | summary of the discharge flow rate control in a controller. It is a figure which shows a pump discharge characteristic. It is a figure which shows schematic structure of the system which has two chemical | medical solution supply pumps. It is a time chart for demonstrating chemical | medical solution discharge operation | movement. It is a block diagram which shows the outline of the chemical | medical solution supply system in 2nd Embodiment. It is a figure which shows the relationship between the diaphragm deformation amount and the discharge amount of a chemical | medical solution. (A) is a figure which shows the conversion type | formula from the diaphragm deformation amount X to the discharge amount q, (b) is a figure which shows the conversion type | formula from the diaphragm deformation speed X / t to the discharge flow rate Q. It is a flowchart which shows the process by the controller regarding movement speed calculation. It is a flowchart which shows the process by the controller regarding actual discharge flow volume calculation. It is a time chart for demonstrating the discharge amount measurement procedure. It is a block diagram which shows the outline of the chemical | medical solution supply system in 3rd Embodiment. It is a time chart for demonstrating a suckback operation | movement.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Chemical solution supply pump, 12 ... Bellows type partition member, 13 ... Pump chamber, 14 ... Pressure action chamber, 15 ... Bellows, 16 ... Partition plate, 23 ... Suction valve, 25 ... Discharge valve, 28 ... Electropneumatic regulator, 35 DESCRIPTION OF SYMBOLS ... Compression coil spring, 36 ... Position detector, 40 ... Controller, 50 ... Chemical solution supply pump, 53 ... Diaphragm, 55 ... Pump chamber, 56 ... Pressure action chamber, 63 ... Suction valve, 65 ... Discharge valve, 69 ... Electropneumatic regulator , 73 ... Rod, 75 ... Compression coil spring, 76 ... Position detector, 80 ... Controller, 100 ... Chemical supply pump, 103 ... Diaphragm, 105 ... Pump chamber, 106 ... Diaphragm operation chamber, 113 ... Suction valve, 115 ... Discharge valve 119: Plunger, 122: Pneumatic operation chamber, 123 ... Fluid chamber, 127 ... Electro-pneumatic regulator, 135 ... Detector, 140 ... controller.

Claims (22)

A pump chamber for filling a chemical solution and a pressure action chamber partitioned from the pump chamber by a volume variable member, and the volume variable member is operated according to the gas pressure in the pressure action chamber, and the operation A chemical supply pump for sucking or discharging the chemical liquid based on the volume change of the pump chamber accompanying
Pressure adjusting means for adjusting the pressure of the gas supplied to the pressure working chamber;
An operation amount detecting means for detecting an operation amount of the variable volume member;
Based on the deviation between the target operating amount and the actual operating amount obtained from the detection result of the operating amount detecting means while setting the target operating amount of the volume variable member at the time of suction or discharge of the chemical solution by the chemical solution supply pump Control means for controlling the pressure adjusting means;
A chemical supply system characterized by comprising:   2. The chemical liquid supply system according to claim 1, further comprising means for calculating a discharge flow rate of the chemical liquid based on a detection result by the operation amount detection means.   The control means sets a target value of the moving speed of the variable volume member as the target operating amount, and the actual moving speed of the variable volume member obtained based on the target value and the detection result by the operating amount detecting means. The chemical solution supply system according to claim 1, wherein the pressure adjusting unit is controlled based on a deviation from the system.   The relationship between the operation amount of the volume variable member and the pump discharge amount is defined, and the control means sets the target value of the moving speed based on the flow rate command value each time using the relationship. The chemical solution supply system according to claim 3.   Means for linearizing the relationship between the operation amount of the volume variable member and the pump discharge amount for each section divided into a plurality of sections within the operation range of the volume variable member, and the control means uses the linearized relationship The chemical solution supply system according to any one of claims 1 to 4, wherein the pressure adjusting means is controlled. A chemical liquid supply system in which an axially expandable / contractible bellows is used as a volume variable member of the chemical liquid supply pump, and an expansion amount of the bellows is detected as an operation amount of the volume variable member by the operation amount detection unit,
6. The chemical solution supply system according to claim 1, wherein the control unit controls the pressure adjusting unit based on an expansion / contraction amount of the bellows. A chemical liquid supply system in which a diaphragm is used as a variable volume member of the chemical liquid supply pump, and a deformation amount of the diaphragm is detected as an operation amount of the volume variable member by the operation amount detection means,
Means for linearizing the relationship between the diaphragm deformation amount and the pump discharge amount for each section divided into a plurality of sections within the deformation range of the diaphragm, and the control means uses the linearized relationship to control the pressure adjusting means. It controls, The chemical | medical solution supply system in any one of Claims 1 thru | or 4 characterized by the above-mentioned.   8. The chemical solution supply system according to claim 7, wherein the relationship between the diaphragm deformation amount and the pump discharge amount is linearized by linear interpolation based on the diaphragm deformation amount and the pump discharge amount at the boundary point of each section.   The detection object is connected to the volume variable member on the pressure acting chamber side, and the operation amount detection means detects a movement amount of the detection object as an operation amount of the volume variable member. The chemical | medical solution supply system in any one of 1 thru | or 8.   The chemical solution supply system according to any one of claims 1 to 9, wherein a plurality of the chemical solution supply pumps are provided, and each of the pumps is alternately operated for suction and discharge. Applying a chemical supply pump provided with a biasing means for biasing the variable volume member in a direction opposite to the gas pressure in the pressure working chamber;
Means for calculating the pressure in the pump chamber based on the operation amount of the volume variable member detected by the operation amount detection means and the gas pressure in the pressure acting chamber;
11. The chemical solution supply system according to claim 1, further comprising means for performing pressure control of the pump chamber based on the calculated pressure in the pump chamber. Applying a chemical supply pump provided with a biasing means for biasing the variable volume member in a direction opposite to the gas pressure in the pressure working chamber;
Means for calculating the pressure in the pump chamber based on the operation amount of the volume variable member detected by the operation amount detection means and the gas pressure in the pressure acting chamber;
The chemical solution according to any one of claims 1 to 10, further comprising means for determining whether or not clogging has occurred in the chemical solution discharge passage leading to the pump chamber by the calculated pressure in the pump chamber. Supply system. Applying a chemical supply pump provided with a suction valve on the suction passage side leading to the pump chamber, and provided with a discharge valve on the discharge passage side leading to the pump chamber,
The state in which the suction valve is closed and the discharge valve is opened and the suction valve is closed and the discharge valve is opened after the completion of the discharge when the chemical solution is discharged in accordance with the operation of the variable volume member. The chemical solution supply system according to any one of claims 1 to 12, wherein the suction of the chemical solution is started by reversing the operation of the volume-variable member while maintaining the state.   14. The chemical solution according to claim 13, wherein after the completion of the discharge of the chemical solution, the time for performing the suction operation of the chemical solution with the suction valve closed and the discharge valve opened, or the suction speed is variably controlled. Supply system. There is a pump chamber for filling the chemical solution and a diaphragm operation chamber that is partitioned from the pump chamber by a diaphragm, and the diaphragm is bent and deformed in accordance with a volume change of the diaphragm operation chamber, and accompanying the bending deformation A chemical supply pump for sucking or discharging the chemical based on a change in volume of the pump chamber,
The diaphragm operation chamber and a fluid chamber communicating with the diaphragm operation chamber are filled with an incompressible fluid, and a movable body that linearly changes the volume of the fluid chamber with respect to an operation amount is provided. And a pressure adjusting means for adjusting the pressure of the gas in the pressure operating chamber is connected to the pressure operating chamber provided on the opposite side of the diaphragm operating chamber.   The chemical supply pump according to claim 15, wherein an effective area of the movable body is smaller than an effective area of the diaphragm.   The movable body is a plunger having a shape having a relatively small area on the side facing the fluid chamber and a relatively large area on the side facing the pressure operation chamber. The described chemical supply pump. A chemical supply pump according to any one of claims 15 to 17,
An operation amount detecting means for detecting an operation amount of the movable body;
Based on the deviation between the target operating amount and the actual operating amount obtained from the detection result by the operating amount detecting means while setting the target operating amount of the movable body at the time of suction or discharge of the chemical liquid by the chemical liquid supply pump Control means for controlling the pressure adjusting means;
A chemical supply system characterized by comprising:   19. The chemical solution supply system according to claim 18, further comprising means for calculating a discharge flow rate of the chemical solution based on a detection result by the operation amount detection means.   The control means sets a target value of the moving speed of the movable body as the target operating amount, and sets the target value and the actual moving speed of the movable body obtained based on the detection result by the operating amount detecting means. The chemical supply system according to claim 18 or 19, wherein the pressure adjusting means is controlled based on a deviation.   The relationship between the operation amount of the movable body and the pump discharge amount is defined, and the control means sets the target value of the moving speed based on the flow rate command value each time using the relationship. The chemical | medical solution supply system of Claim 20.   The chemical solution supply system according to any one of claims 18 to 21, wherein a plurality of the chemical solution supply pumps are provided, and each of these pumps is alternately operated for suction and discharge.

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