JP4526350B2 - Chemical supply pump - Google Patents

Description

  The present invention relates to a chemical solution supply pump suitable for applying a predetermined amount of a chemical solution such as a photoresist solution to each semiconductor wafer in a chemical solution use step of a semiconductor manufacturing apparatus, for example.

  An example of a chemical solution supply pump that draws a chemical solution such as a photoresist solution from a bottle and applies a predetermined amount to each semiconductor wafer is disclosed in Patent Document 1, for example. In this pump, a pump chamber and a working chamber (a pressurizing chamber in the publication) are partitioned by a diaphragm, and the diaphragm is driven by supplying / exhausting working air to / from the working chamber through a supply / discharge passage communicating with the working chamber. The volume in the pump chamber is changed, and the chemical solution is discharged and sucked in the pump chamber.

  By the way, when the pump chamber and the working chamber are formed thin and a diaphragm made of a flexible membrane is used to make the pump thin, the peripheral portion of the diaphragm is fixed, so that the deformation from the center portion thereof is possible. Is likely to occur. On the other hand, in order to efficiently deform the entire diaphragm, it is desirable to set the opening in the working chamber of the supply / discharge passage at the center of the working chamber.

As a result, when the working chamber is evacuated to suck the chemical into the pump chamber or when the working chamber is opened to the atmosphere and the chemical is supplied under pressure, deformation from the center of the diaphragm to the working chamber starts. It is easy for the part to come into contact with the inner wall surface of the working chamber first. In such a case, the central portion of the diaphragm closes the opening of the supply / discharge passage with the periphery of the central portion floating from the inner wall surface of the working chamber, and it takes time to deform the diaphragm to the working chamber side. However, it becomes impossible to deform any more and the deformation becomes insufficient. For this reason, it takes a long time to fill the pump chamber with the chemical solution, or the pump chamber cannot be filled with a predetermined amount of the chemical solution.
JP 2003-49778 A

  The main object of the present invention is to provide a chemical supply pump capable of ensuring that the diaphragm is deformed to the working chamber side in a short time and reliably, and that the chemical solution filling time in the pump chamber is shortened and a sufficient amount of chemical solution is secured. It is the purpose.

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

Means 1. A diaphragm (diaphragm 23) made of a flexible membrane partitions the pump chamber (pump chamber 25) and the working chamber (working chamber 26), and the working chamber is pressurized using working gas, whereby the diaphragm is The chemical solution (resist solution R) that is deformed to the pump chamber side and is filled in the pump chamber is discharged, and the working chamber is made negative by suction of the working gas, or the working chamber is opened to the atmosphere. The diaphragm is deformed to the working chamber side by the chemical liquid supply pump for sucking the chemical liquid into the pump chamber,
In the pump housing (pump housing 22), a supply / discharge passage (supply / discharge passage 22b) for supplying and discharging the working gas is formed in the working chamber, and a part of the inner wall surface (inner wall surface 22c) of the working chamber is provided with the above-mentioned. An opening (opening 22d) of the supply / discharge passage is provided,
The chemical supply pump according to claim 1, wherein a vent groove (ventilation grooves 22e, 22f) is formed on the inner wall surface of the working chamber so as to extend from the opening of the supply / discharge passage toward the peripheral edge of the inner wall surface.

  According to the means 1, an opening of the supply / discharge passage is provided in a part of the inner wall surface of the working chamber, and a ventilation groove that extends from the opening of the supply / discharge passage to the peripheral edge side of the inner wall surface is formed. Here, when the chemical solution is inhaled, the working gas in the working chamber is discharged (sucked) through the supply / discharge passage. In this case, the diaphragm is easily deformed from the central portion, and the central portion may first cover the opening portion of the supply / discharge passage. However, as described above, the opening of the supply / discharge passage communicates with the ventilation groove that develops toward the peripheral edge of the working chamber, so that the central portion of the diaphragm is deformed so as to cover the opening portion of the supply / discharge passage first. In addition, the vent groove located on the outer side from the abutted central portion is in an open state, and the discharge (suction) of the working gas in the working chamber can be continued from the vent groove in the open state. For this reason, even when such a deformation occurs in the diaphragm, the deformation of the diaphragm to the working chamber side is ensured in a short time and reliably, and the time for filling the pump chamber with the chemical solution is shortened and a sufficient amount of the chemical solution is ensured. it can.

  It should be noted that the development destination of the above-described ventilation groove is desirably closer to the peripheral edge of the working chamber, and is best extended to the peripheral edge. In this way, the ventilation groove can be prevented from being blocked by the diaphragm until the diaphragm is sufficiently deformed to the working chamber side, and the discharge (suction) of the working gas in the working chamber is ensured.

  Mean 2. The inner wall surface of the working chamber has a circular shape, and the opening of the supply / exhaust passage is located at the center of the inner wall surface of the working chamber. pump.

  According to the means 2, since the opening of the supply / discharge passage is located at the center of the inner wall surface of the circular working chamber, the working gas in the working chamber can be efficiently supplied and discharged.

  Means 3. The inner wall surface of the working chamber has an opening of the supply / exhaust passage at the center thereof and is formed in a symmetrical shape with the center portion as the center, and the ventilation groove corresponds to the inner wall surface of the working chamber. The chemical solution supply pump according to claim 1, wherein the pump is formed in a symmetrical shape with the center of the opening of the supply / discharge passage as its center.

  According to the means 3, the vent groove is formed in a symmetrical shape with the central portion of the inner wall surface of the working chamber having the opening of the supply / exhaust passage as its center, so that the central portion of the diaphragm comes first when the chemical solution is inhaled. When a state of covering the opening portion of the supply / exhaust passage occurs, it is possible to bring the working chamber into a stable negative pressure state by this ventilation groove, and it is possible to stably deform the diaphragm.

  Means 4. The said liquid supply groove | channel has comprised the linear shape, The pump for chemical | medical solution supply in any one of the means 1-3 characterized by the above-mentioned.

  According to the means 4, since the ventilation groove is formed in a straight line, the ventilation groove can be easily formed.

  Means 5. 3. The means 1 or 2, wherein the ventilation groove (venting groove 22 f) is configured by a continuous recess (recess 22 g) formed by forming the inner wall surface of the working chamber into a rough surface. Chemical solution pump.

  According to the means 5, since the ventilation groove is constituted by a continuous recess formed by forming the inner wall surface of the working chamber into a rough surface, the ventilation groove can be easily formed only by roughening the inner wall surface.

  The roughening of the inner wall surface can be easily formed by spraying shot blasting, that is, a particulate abrasive.

  Means 6. 6. The chemical supply pump according to claim 5, wherein the inner wall surface of the working chamber is roughened over the entire inner wall surface.

  According to the means 6, since the roughening of the inner wall surface of the working chamber is performed on the entire inner wall surface corresponding to the deformation region of the diaphragm, the region to be roughened on the inner wall surface of the working chamber and the others are arranged. There is no need to distinguish, and the inner wall surface can be easily roughened. In addition, since the entire inner wall surface of the working chamber becomes a rough surface, it is possible to prevent the ventilation groove from being blocked by the diaphragm until the diaphragm is sufficiently deformed to the working chamber side. (Suction) is ensured.

  Mean 7 The chemical liquid supply pump according to any one of means 1 to 6, wherein the pump housing is formed thin in the deformation direction of the diaphragm.

  According to the means 7, since the pump housing is formed thin in the deformation direction of the diaphragm, the working chamber needs to be formed thin in the same direction. For this reason, at the time of inhalation of the chemical solution, since the center portion of the diaphragm is likely to come into contact with the inner wall surface of the working chamber first, it is significant to provide the ventilation groove as described above.

  Hereinafter, an embodiment in which the present invention is embodied in a pump unit of a chemical solution supply system used in a production line for semiconductor devices or the like will be described with reference to the drawings. 1 and 2 show a pump unit 10 which is a main part of the system, and FIG. 3 shows an entire chemical solution supply system.

  As shown in FIGS. 1 and 2, the pump unit 10 includes a pump 11, an electromagnetic switching valve 12, a suction side cutoff valve 13, a discharge side cutoff valve 14, a suck back valve 15, a regulator device 16, and a suction side flow path member 17. In addition, the discharge side flow path member 18 is integrally assembled into a unit.

  The pump 11 is a substantially square prismatic and thin flat shape, and has a pair of pump housings 21 and 22. The pump housings 21 and 22 are respectively provided with recessed portions 21a and 22a that are recessed in a substantially circular dome shape at the center of the opposing surfaces. The pump housings 21 and 22 sandwich the periphery of a diaphragm 23 made of a flexible film such as a circular fluororesin at the periphery of the recessed portions 21 a and 22 a, and are fixed to each other by eight screws 24.

  The diaphragm 23 partitions the space formed by the two recessed portions 21a and 22a of the pump housings 21 and 22, and the space on the pump housing 21 side (left side of the diaphragm 23 in FIG. 2) serves as a pump chamber 25. The space on the housing 22 side (the right side of the diaphragm 23 in FIG. 2) is used as the working chamber 26. The pump chamber 25 is a space for supplying and discharging a resist solution R (see FIG. 3) as a chemical solution, and the working chamber 26 is a space for supplying and discharging operating air that drives the diaphragm 23. Incidentally, in order to reduce the thickness of the pump 11, the pump housings 21 and 22 are formed thin (in this case, the deformation direction of the diaphragm 23), whereby the pump chamber 25 and the working chamber 26 form a thin space in the same direction.

  The pump housing 21 on the pump chamber 25 side is formed with a suction passage 21b that communicates with the pump chamber 25 and extends downward linearly. The suction passage 21 b communicates with the suction passage 17 a of the suction side flow path member 17. The pump housing 21 is formed with a discharge passage 21c that communicates with the pump chamber 25 and extends linearly upward. The discharge passage 21 c communicates with the discharge passage 18 a of the discharge side flow path member 18. The discharge passage 21c is provided on the same straight line L1 as the suction passage 21b. Since the pump chamber 25 of the present embodiment is formed in a thin space in the deformation direction of the diaphragm 23, portions near the suction passage 21b and the discharge passage 21c communicating with the pump chamber 25 are necessary for connection. It is bent at a right angle (about the passage width) (see FIG. 2). Therefore, the flow of the resist solution R in this portion is smooth, and does not have a great influence (resistance) on the flow of the resist solution R in the pump 11.

  The pump housing 22 on the working chamber 26 side is formed with a supply / discharge passage 22 b for supplying and discharging working air into the working chamber 26. The opening 22d of the supply / discharge passage 22b in the inner wall surface 22c of the working chamber 26 (the recessed portion 22a) is located at the center of the circular recessed portion 22a. Further, as shown in FIG. 4, the inner wall surface 22c of the working chamber 26 is formed with a cross-shaped ventilation groove 22e whose end extends to the peripheral edge of the working chamber 26, and an intersection of the cross-shaped ventilation groove 22e. The opening 22d of the supply / discharge passage 22b is located in the portion. The supply / discharge passage 22 b is connected to the electromagnetic switching valve 12 fixed to the pump housing 22.

  Here, as shown in FIG. 3, the electromagnetic switching valve 12 has an air supply port connected to one end of the air supply pipe 28a. The air supply pipe 28a has an electropneumatic regulator 27 in the middle, and the other end of the pipe 28a is connected to the supply source 29a. The electropneumatic regulator 27 is adjusted by the controller 50 so that the pressure of the working air supplied from the supply source 29a to the pump 11 is constant. The exhaust port of the electromagnetic switching valve 12 is connected to a vacuum generation source 29b through an exhaust pipe 28b. The electromagnetic switching valve 12 is switched by the controller 50 so as to connect the working chamber 26 to either the supply source 29a or the vacuum generation source 29b. With this switching operation, the working air is supplied to and discharged from the working chamber 26. The discharge / suction operation is switched.

  That is, when the working air is supplied to the working chamber 26 by the operation of the electromagnetic switching valve 12, the inside of the working chamber 26 is pressurized and the diaphragm 23 is actuated to the pump chamber 25 side, and the resist filled in the pump chamber 25 is filled. The liquid R is discharged downstream via the discharge passage 21c. On the other hand, when the operation air in the working chamber 26 is evacuated by the operation of the electromagnetic switching valve 12 and the inside of the working chamber 26 becomes negative pressure, the diaphragm 23 that has been operated on the pump chamber 25 side operates on the working chamber 26 side, The resist solution R is sucked into the pump chamber 25 from the upstream side through the suction passage 21b.

  Here, at the time of inhalation of the resist solution R, the diaphragm 23 is deformed to the maximum deformation position where it abuts against the inner wall surface 22c of the working chamber 26, as shown in FIG. As shown in FIG. 5 (b), the diaphragm 23 is easily deformed from the central portion during this deformation, and the central portion first covers the opening 22d portion of the supply / discharge passage 22b before being deformed to the maximum deformation position. Sometimes. In this case, since the opening 22d communicates with the ventilation groove 22e extending to the peripheral edge of the working chamber 26, even if the central portion of the diaphragm 23 is deformed so as to cover the opening 22d portion of the supply / discharge passage 22b first, The ventilation groove 22e located on the outer side from the contacted central portion is in an open state, and the evacuation in the working chamber 26 can be continued from the open ventilation groove 22e (the flow of the working air in FIG. 5B). Is indicated by an arrow). Therefore, even when such deformation occurs in the diaphragm 23, the diaphragm 23 can be reliably deformed in a short time to the maximum deformation position, and the filling time of the resist solution R into the pump chamber 25 can be shortened and the filling amount can be reduced. It can be secured sufficiently.

  A suction-side flow path member 17 having a rod shape is fixed to the lower center of the pump housings 21 and 22. The suction side flow path member 17 is provided along the flat direction of the pump 11. A suction passage 17a is formed in the suction-side flow path member 17 so as to extend downward substantially linearly. The suction passage 17a is provided on the same straight line L1 as the suction passage 21b of the pump 11. A housing recess 17b is formed around the suction passage 17a on the surface of the suction side flow path member 17 facing the pump housing 21, and a seal ring 33 is housed in the housing recess 17b. The seal ring 33 is interposed between the suction-side flow path member 17 and the pump housing 21, and seals the resist solution R in the suction passages 17a and 21b from leaking from the gap between the two members.

  The seal ring 33 has a shape in which the inner peripheral surface 33a thereof is smoothly connected to the inner peripheral surfaces of the suction passages 17a and 21b. Specifically, the seal ring 33 gradually increases from the suction passages 17a and 21b toward the central portion. It has a concave shape on the outside in the radial direction. That is, the flow of the resist solution R in the seal ring 33 is made smooth, and the resist solution R and bubbles are prevented from staying. Incidentally, when a generally used circular seal ring (O-ring) is used, an acute-angle depression is generated between the seal ring and each of the suction passages 17a and 21b. Since the shape does not smoothly connect to the peripheral surface, this becomes a portion where the resist solution R and bubbles stay, which is not preferable. As shown in FIG. 3, the suction-side flow path member 17 uses a joint 19 provided at the tip portion of the suction pipe 31 led into the resist solution R filled in the resist bottle 30 as shown in FIG. Connected to the other end.

  In addition, a suction side shutoff valve 13 made up of an air operated valve is integrally assembled with the suction side flow path member 17. The suction side shut-off valve 13 has a substantially rectangular column shape, and is provided in a direction orthogonal to the suction side flow path member 17 and along the flat direction of the pump 11 (pump housings 21 and 22). Here, as shown in FIG. 3, the suction side shutoff valve 13 switches between shutting off and opening the suction passage 17 a by the switching operation of the electropneumatic regulator 32 based on the control of the controller 50. That is, as shown in FIG. 1, when the supply / discharge chamber 13a is opened to the atmosphere by the switching operation of the electropneumatic regulator 32, the suction side shut-off valve 13 receives the urging force from the spring 13c. When the suction passage 17a is shut off and operating air is supplied from the supply source 29a to the supply / discharge chamber 13a, the valve body 13b is immersed against the urging force of the spring 13c to open the suction passage 17a. ing. Note that the suction passage 17a in the vicinity of the valve body 13b is bent at a right angle by an amount necessary for reliably opening or shutting off the valve body 13b (about the passage width). For this reason, the flow of the resist solution R is smooth even in this portion, and the flow of the resist solution R in the flow path member 17 is not greatly affected (resistance).

  A discharge side flow path member 18 having a rod shape is fixed to the upper center of the pump housings 21 and 22. The discharge-side flow path member 18 is provided along the flat direction of the pump 11. A discharge passage 18 a that extends substantially linearly upward is formed in the discharge-side flow path member 18. The discharge passage 18a is provided on the same straight line L1 as the discharge passage 21c of the pump 11. An accommodation recess 18b is formed around the discharge passage 18a on the surface of the discharge-side flow path member 18 facing the pump housing 21, and a seal ring 34 is accommodated in the accommodation recess 18b. The seal ring 34 is interposed between the discharge-side flow path member 18 and the pump housing 21 and seals the resist solution R in the discharge passages 18a and 21c from leaking from the gap between the members.

  Further, like the seal ring 33, the seal ring 34 has a shape in which the inner peripheral surface 34a thereof is smoothly connected to the inner peripheral surfaces of the discharge passages 18a and 21c, and the resist solution R and bubbles remain. It is the structure which prevents. And the discharge side flow path member 18 is connected with the other end of the discharge piping 35 which has the nozzle 35a at one end using the coupling 20 provided in the front-end | tip part, as shown in FIG. The nozzle 35 a is directed downward, and is disposed at a position where the resist solution R is dropped at the center position of the semiconductor wafer 37 that is placed on the rotating plate 36 and rotates together with the rotating plate 36.

  Further, the discharge side flow path member 18 is integrally assembled with a discharge side shut-off valve 14 formed of an air operated valve. The discharge side shut-off valve 14 has a substantially square column shape, and is provided in a direction orthogonal to the discharge side flow path member 18 and along the flat direction of the pump 11 (pump housings 21 and 22). Here, the discharge side shut-off valve 14 is configured in the same manner as the suction side shut-off valve 13, and as shown in FIG. 3, the discharge passage 18 a is shut off and switched by the switching operation of the electropneumatic regulator 38 based on the control of the controller 50. Switch open. That is, as shown in FIG. 1, when the supply / discharge chamber 14a is opened to the atmosphere by the switching operation of the electropneumatic regulator 38, the discharge side shut-off valve 14 receives the urging force from the spring 14c. When the discharge passage 18a is shut off and operating air is supplied to the supply / discharge chamber 14a from the supply source 29a, the valve body 14b is immersed against the urging force of the spring 14c to open the discharge passage 18a. ing. The discharge passage 18a in the vicinity of the valve body 14b is bent at a right angle by an amount necessary for reliably opening or shutting off the valve body 14b (about the passage width). For this reason, the flow of the resist solution R is smooth even in this portion, and the flow of the resist solution R in the flow path member 18 is not greatly affected (resistance).

  Further, a suck-back valve 15 made of an air operated valve is integrally assembled with the discharge side flow path member 18 so as to be aligned with the shutoff valve 14 on the downstream side of the discharge side shutoff valve 14. Similarly, the suck-back valve 15 has a substantially quadrangular prism shape, and is provided in a direction orthogonal to the discharge-side flow path member 18 and along the flat direction of the pump 11 (pump housings 21 and 22). Here, as shown in FIG. 3, the suck back valve 15 places the resist solution R in the flow path downstream from the valve 15 on the upstream side by the switching operation of the electropneumatic regulator 39 based on the control of the controller 50. The fixed amount is drawn to prevent the dripping of the resist solution R from the nozzle 35a. That is, as shown in FIG. 1, when the supply / discharge chamber 15a is opened to the atmosphere by the switching operation of the electropneumatic regulator 39, the valve body 15b receives the urging force from the spring 15c and is immersed. Then, the volume of the volume expansion chamber 18c provided in communication with the discharge passage 18a is increased, and a predetermined amount of the resist solution R is drawn into the volume expansion chamber 18c. On the other hand, when the working air is supplied from the supply source 29a to the supply / discharge chamber 15a, the valve body 15b protrudes against the urging force of the spring 15c to reduce the volume expansion chamber 18c provided in the discharge passage 18a. Has been.

  Further, a regulator device 16 having a substantially rectangular parallelepiped shape is fixed to the discharge side flow path member 18 on the side opposite to the discharge side shutoff valve 14 and the suck back valve 15. That is, the regulator device 16 is provided with respect to the discharge-side flow path member 18 along the flat direction of the pump 11. The regulator device 16 has a base member 41 fixed to the discharge-side flow path member 18. A fixed base 42 is fixed to the base member 41, and electropneumatic regulators 38 and 39 for switching the discharge side shut-off valve 14 and the suck back valve 15 are fixed to the fixed base 42. A cover member 43 that covers the electropneumatic regulators 38 and 39 is attached to the fixed base 42. Further, the fixed base 42 and the base member 41 are respectively formed with communication passages 45 and 46 communicating with the electropneumatic regulators 38 and 39. The communication passages 45 and 46 are not shown, but are connected to the discharge side shut-off valve 14 and the sucker. The back valve 15 communicates with the supply / discharge chambers 14a and 15a, respectively. The electropneumatic regulators 38 and 39 supply and discharge operating air to and from the supply / discharge chambers 14a and 15a of the discharge side shut-off valve 14 and suck back valve 15 based on the control of the controller 50, respectively. 15 is activated.

  In the pump unit 10 configured as described above, the suction passage 17a in the suction-side flow path member 17 that is the flow path of the resist solution R, the suction passage 21b and the discharge passage 21c in the pump 11, and the discharge side flow Both the discharge passage 18a of the path member 18 are linear and are arranged on the same straight line L1. In other words, the pump unit 10 has a structure in which the resist solution R and bubbles are retained in the flow path of the resist solution R as much as possible while reducing the flow path length of the resist solution R as much as possible. Also, the seal rings 33 and 34 have a structure in which the portion where the resist solution R and bubbles stay is reduced as much as possible.

  As shown in FIG. 3, the controller 50 controls the electropneumatic regulator 27 so that the working air supplied to the pump 11 becomes a set pressure, and also performs an electromagnetic switching valve 12 and a suction side shut-off valve that perform a switching operation of the pump 11. 13 controls the electropneumatic regulator 32 that switches the operation 13, the electropneumatic regulators 38 and 39 that operate the discharge side shut-off valve 14 and the suck back valve 15, and controls a series of operations of the chemical solution supply system.

  That is, when a command to start the operation of the chemical solution supply system is generated, the controller 50 first controls the electropneumatic regulator 32 to switch the suction side shutoff valve 13 and put the suction passage 17a into a shutoff state. As a result, the pump 11 and the resist bottle 30 are shut off. Further, the controller 50 switches the electromagnetic switching valve 12 and supplies the working air adjusted to the set pressure to the working chamber 26 in the pump 11. As a result, the diaphragm 23 tries to operate toward the pump chamber 25 and pressurizes the resist solution R filled in the pump chamber 25. At this time, the discharge passage 18a is shut off by the discharge side shut-off valve 14 on the downstream side of the pump 11, and the resist solution R is not discharged.

  Next, the controller 50 controls the electropneumatic regulator 38 to switch the discharge side shut-off valve 14 to open the discharge passage 18a, and also controls the electropneumatic regulator 39 to release the drawing of the resist solution R by the suck back valve 15. . At this time, since the resist solution R in the pump chamber 25 is pressurized by the diaphragm 23, the resist solution R is discharged from the pump 11, and the resist solution R is discharged from the nozzle 35a at the tip of the discharge pipe 35 through the discharge passage 18a. A predetermined amount is dropped on the semiconductor wafer 37.

  Next, the controller 50 controls the electropneumatic regulator 38 to switch the discharge side shutoff valve 14 and shut off the discharge passage 18a. Thereby, the discharge of the resist solution R from the nozzle 35a is stopped. Further, the controller 50 controls the electropneumatic regulator 39 to draw a predetermined amount of the resist solution R by the suck back valve 15, and prevents the resist solution R from dripping unexpectedly from the nozzle 35a.

  Next, the controller 50 controls the electropneumatic regulator 32 to switch the suction side shutoff valve 13 and open the suction passage 17a. As a result, the pump 11 and the resist bottle 30 are in communication with each other. Further, the controller 50 switches the electromagnetic switching valve 12 and sucks the working air in the working chamber 26 by the vacuum generation source 29b. Then, the inside of the working chamber 26 becomes negative pressure, the diaphragm 23 is deformed to the maximum deformation position where it abuts against the inner wall surface 22c of the working chamber 26, and the resist solution R is sucked into the pump chamber 25 and filled.

  At the time of this inhalation, when the central portion of the diaphragm 23 first covers the opening 22d portion of the supply / discharge passage 22b, the opening 22d communicates with the ventilation groove 22e extending to the peripheral portion of the working chamber 26. The working chamber 26 is continuously evacuated from the ventilation groove 22e located on the outer side from the central portion that has been previously contacted. Therefore, even when such deformation occurs in the diaphragm 23, the diaphragm 23 can be reliably deformed in a short time to the maximum deformation position on the working chamber 26 side, and the filling time of the resist solution R into the pump chamber 25 is increased. Shortening and filling amount can be secured sufficiently. Thereafter, the controller 50 repeats the above-described operation so that a predetermined amount of the resist solution R is dropped onto each semiconductor wafer 37 that is successively transferred.

  Next, the characteristic operational effects of the present embodiment will be described.

  In the present embodiment, the opening 22d of the supply / discharge passage 22b is located at the center of the inner wall surface 22c of the working chamber 26 (concave portion 22a), and the inner wall surface 22c extends from the opening 22d of the supply / discharge passage 22b. A cross-shaped ventilation groove 22e is formed on the peripheral edge side. When the resist solution R is sucked, the working air in the working chamber 26 is sucked through the supply / discharge passage 22b. In this case, the diaphragm 23 is easily deformed from the central portion, and the central portion may first cover the opening 22d portion of the supply / discharge passage 22b. However, since the opening 22d of the supply / discharge passage 22b communicates with the ventilation groove 22e developed at the peripheral edge of the working chamber 26 as in the present embodiment, even if the diaphragm 23 is deformed in this way, it abuts. The ventilation groove 22e located outside from the central portion is in an open state, and the suction of the working air in the working chamber 26 can be continued from the opened ventilation groove 22e. Therefore, even when such a deformation occurs in the diaphragm 23, the deformation of the diaphragm 23 is ensured in a short time to the maximum deformation position on the working chamber 26 side, and the filling time of the resist solution R into the pump chamber 25 is ensured. Shortening and filling amount can be secured sufficiently.

  In the present embodiment, the opening 22d of the supply / discharge passage 22b is located at the center of the inner wall surface 22c of the working chamber 26 having a circular shape, so that the supply and discharge of the working air in the working chamber 26 is efficient. Can be done well.

  In the present embodiment, since the ventilation groove 22e extends to the peripheral edge of the working chamber 26, the ventilation groove 22e is not blocked by the diaphragm 23 until the diaphragm 23 is sufficiently deformed to the working chamber 26 side. Therefore, the working air in the working chamber 26 can be reliably sucked.

  In the present embodiment, the ventilation groove 22e is formed in a cross shape having a symmetrical shape with the central portion of the inner wall surface 22c of the circular working chamber 26 (concave portion 22a) having a symmetrical shape as its center. . Therefore, when the central portion of the diaphragm 23 first covers the opening 22d portion of the supply / discharge passage 22b at the time of inhalation of the resist solution R, a stable negative pressure state is established in the working chamber 26 by the ventilation groove 22e. The diaphragm 23 can be stabilized and deformed.

  In the present embodiment, since the ventilation groove 22e is formed in a straight line, the ventilation groove 22e can be easily formed.

  In the present embodiment, the pump housing 22 is formed thin in the deformation direction of the diaphragm 23 in order to reduce the thickness of the pump 11, and therefore the working chamber 26 is also formed thin in the same direction. Therefore, at the time of inhalation of the resist solution R, the central portion of the diaphragm 23 is likely to come into contact with the inner wall surface 22c of the working chamber 26 first, so that the provision of the ventilation groove 22e as described above is significant.

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

  In the above embodiment, the cross-shaped ventilation groove 22e is formed on the inner wall surface 22c of the working chamber 26 (concave portion 22a), but the shape of the ventilation groove is not limited to this. For example, the ventilation groove 22e has a cross shape, that is, a shape extending in four directions from the opening 22d, but may be a Y-shaped ventilation groove extending in three directions from the opening 22d. Moreover, it is good also as a shape which extended the ventilation groove | channel in the direction of the even number or odd number other than these. When the shape of the ventilation groove is changed, it is desirable that the ventilation groove be closer to the peripheral portion of the working chamber 26, and it is best to extend to the peripheral portion of the working chamber 26 (concave portion 22a) as in the above embodiment. It is.

  Further, as indicated by dots in FIG. 6, the entire inner wall surface 22c of the working chamber 26 is formed into a rough surface, and as shown by the wavy line in FIG. Thus, the ventilation groove 22f may be configured. Even in this case, when the resist solution R is inhaled, as shown in FIG. 7A, if the central portion of the diaphragm 23 covers the opening 22d portion of the supply / discharge passage 22b first, Since 22d communicates with the ventilation groove 22f that expands by the continuous recess 22g up to the peripheral edge of the working chamber 26, the inside of the working chamber 26 is evacuated from the ventilation groove 22f that is located outward from the central portion that has been contacted first. The operation is continuously performed (in FIG. 7B, the flow of the working air is indicated by an arrow). Even if it does in this way, the effect similar to the said embodiment can be acquired.

  In addition, the roughening of the inner wall surface 22c can be easily formed by spraying shot blasting, that is, a particulate abrasive. Moreover, the roughening of the inner wall surface 22c is performed on the entire inner wall surface 22c, so that it is easy to roughen the inner wall surface 22c without masking the area that is not roughened on the inner wall surface 22c. .

  In the embodiment described above, the opening 22d of the supply / discharge passage 22b is set at the center of the working chamber 26 (recessed portion 22a), but may be set at a position offset from the center.

  In the above embodiment, the working chamber 26 is set to a negative pressure when the resist solution R is sucked, but it may be opened to the atmosphere. In this case, for example, the inside of the resist bottle 30 is pressurized to cope with it.

  In the above-described embodiment, the pump unit 10 in which the shutoff valves 13 and 14 and the suck back valve 15 and the like are integrally assembled with the pump 11 as the chemical solution supply pump is implemented. You may do it.

  In the above embodiment, the working air (air) has been described as an example, but other gases such as nitrogen may be used in addition to air.

  In the above-described embodiment, the example in which the resist solution R is used as the chemical solution has been described. This is because the chemical solution is to be dropped on the semiconductor wafer 37. Therefore, the chemical solution and the dripping target of the chemical solution may be other than that.

It is a front sectional view showing a pump unit in a chemical solution supply system. (A) is a sectional side view of a pump unit, (b) is an expanded sectional view of (a). It is circuit explanatory drawing which shows the whole circuit of a chemical | medical solution supply system. (A) is a front view of the pump housing by the side of a working chamber, (b) is an AA sectional view of (a). (A) (b) is explanatory drawing for demonstrating the operation | movement of a diaphragm. (A) is a front view of the pump housing on the working chamber side in another example, (b) is a BB cross-sectional view of (a). (A) (b) is explanatory drawing for demonstrating the operation | movement of the diaphragm in another example.

Explanation of symbols

  22 ... Pump housing, 22b ... Supply / discharge passage, 22c ... Inner wall surface, 22d ... Opening, 22e ... Ventilation groove, 22f ... Ventilation groove, 22g ... Recess, 23 ... Diaphragm, 25 ... Pump chamber, 26 ... Working chamber, R ... Resist solution (chemical solution).

Claims (7)

The pump chamber and the working chamber are partitioned by a diaphragm made of a flexible membrane, and the working chamber is pressurized with working gas, whereby the diaphragm is deformed to the pump chamber side and filled into the pump chamber. The inside of the working chamber is made negative by suction of the working gas, or the working chamber is opened to the atmosphere, and the diaphragm is deformed to the working chamber side to suck the chemical into the pump chamber. A pump for supplying chemical liquid,
In the pump housing, a supply / discharge passage for supplying and discharging the working gas is formed in the working chamber, and an opening of the supply / discharge passage is provided in a part of an inner wall surface of the working chamber,
A pump for supplying a chemical solution, wherein a vent groove is formed on the inner wall surface of the working chamber so as to extend from the opening of the supply / discharge passage toward the peripheral edge of the inner wall surface. The inner wall surface of the working chamber has a circular shape,
2. The chemical liquid supply pump according to claim 1, wherein the opening of the supply / discharge passage is located in a central portion of an inner wall surface of the working chamber. The inner wall surface of the working chamber has an opening of the supply / exhaust passage at the center thereof, and is formed in a symmetrical shape with the center portion as the center,
2. The chemical supply pump according to claim 1, wherein the ventilation groove is formed in a symmetrical shape with the center of the opening of the supply / exhaust passage corresponding to the inner wall surface of the working chamber. .   The said ventilation groove has comprised the linear shape, The pump for chemical | medical solution supply in any one of Claims 1-3 characterized by the above-mentioned.   3. The chemical liquid supply pump according to claim 1, wherein the ventilation groove is constituted by a continuous recess formed by forming the inner wall surface of the working chamber into a rough surface.   6. The chemical liquid supply pump according to claim 5, wherein the inner wall surface of the working chamber is roughened over the entire inner wall surface.   The chemical pump according to any one of claims 1 to 6, wherein the pump housing is formed thin in the deformation direction of the diaphragm.

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