JP2010025171A - Delivery controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a delivery controller used for supplying fluid such as a chemical to a semiconductor wafer or for dripping a fixed amount of the chemical in the medical field. <P>SOLUTION: A body 1 is provided with an almost conical shape liquid chamber 6 in the center of an upper surface, and a first flow passage 4 and a second flow passage 5 communicated with the liquid chamber 6. A bottom surface of the liquid chamber 6 is flat, and the lowermost position of an inside diameter of the first flow passage 4 and the second flow passage 5 is almost flush with the bottom surface of the liquid chamber 6. A hood 2 of the upper surface of the body 1 has an almost conical shape air chamber 7 which is communicated with the outside through a vent hole 8 in a size of ϕ0.3 mm. A diaphragm 3 comprises a center part plane and thicker than other parts, a thin film part extended to a radial outer side, and an annular outer peripheral part, and the outer peripheral part is held and fixed by the body 1 and the hood 2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a discharge controller used for fluid transport piping in various industries such as a chemical factory, a semiconductor manufacturing field, a food field, a medical field, and a bio field, and more particularly, a semiconductor wafer in a semiconductor manufacturing apparatus. The present invention relates to a discharge controller that is used in a piping line that supplies a fluid such as a chemical liquid to the pipe or that is used for control for dropping a predetermined amount of a chemical liquid in the medical field.

  2. Description of the Related Art Conventionally, in a semiconductor cleaning apparatus, particularly an apparatus that directly applies a chemical solution to the surface of a semiconductor wafer and performs various processes, a piping line for supplying a chemical solution as shown in FIG. In this piping line, the chemical liquid is caused to flow from the chemical liquid tank 61 to the pipe 64 by the pump 62, and the chemical liquid is discharged from the discharge portion 65 to the semiconductor wafer 66. In order to supply and stop the chemical liquid, it is common to use a diaphragm type on-off valve 63 driven by air interposed in the middle of the pipe 64. At this time, the length of the pipe 64 from the on-off valve 63 to the discharge part 65 is usually about 2 to 4 m due to the design of the cleaning device.

In such a piping line, when the flow of fluid is suddenly stopped by the on-off valve 63, the diaphragm is deformed by the volume change in the valve chamber of the on-off valve 63 and the chemical liquid is pushed out to the downstream side, and the discharge end 65 at the end of the piping. There is a problem that the chemical solution may jump out more vigorously, and such a rapid change in the flow rate has a problem of adversely affecting the wafer processing.
After that, even if the fluid flow is suddenly stopped by the on-off valve 63, it tends to flow downstream due to the inertia of the fluid flow, so that a negative pressure is generated in the pipe 64 on the downstream side of the on-off valve 63. The negative pressure varies depending on the length of the pipe 64 downstream of the on-off valve 63 and the flow velocity of the fluid, but a phenomenon in which the fluid is sucked back in the reverse direction by the action of the negative pressure occurs in the discharge section 65 at the end of the pipe. As shown in FIG. 11, the air is sucked up to the atmosphere together and becomes a bubble 68 between the chemical liquid 67 and the remaining chemical liquid 69 in the piping of the discharge section 65 and remains in the chemical liquid 67. When the discharge of the chemical solution 67 is resumed in this state, the bubbles 68 are applied to the semiconductor wafer 66 together with the chemical solution 67, thereby causing unevenness in the surface treatment of the wafer, and the uneven portion becomes a defective product. There was a problem. Further, for example, in the medical field, this problem has been a hindrance to strict control of the amount of chemical solution that is ejected or sucked back when a fixed amount of the chemical solution is dropped.

As a method for solving the above problem, in general, a negative pressure on the downstream side or extrusion of a chemical solution is prevented by installing a speed controller in an air pipe that opens and closes the on-off valve 63 to slow down the closing speed. The method is used.
However, when the closing operation of the on-off valve 63 is delayed using a speed controller, a stop signal to the on-off valve 63 is output from a control unit (not shown) of the cleaning device until the on-off valve 63 actually closes. Delay time occurs. Therefore, when it is desired to precisely adjust the discharge amount of the chemical solution, it is necessary to give a stop signal to the on-off valve 63 early in anticipation of this delay time. The delay time depends on the operating air pressure of the on-off valve 63 and the individual difference of the on-off valve. There is also a problem that it is difficult to control at a certain time. In addition, there is a problem that adjustment of the speed controller needs to be carried out by a skilled worker for each vehicle, which takes time and effort.

Accordingly, various water hammer prevention devices, accumulators, and the like have been proposed as means for preventing the above-described negative pressure generation and chemical liquid extrusion without inconveniences such as a speed controller.
There is a water hammer prevention device as shown in FIG. 12, and a metal bellows 74 filled with nitrogen gas is disposed in an internal space 73 communicating with the input port 71 and the output port 72. The inflowing fluid passes through the outer periphery of the metal bellows 74 and is discharged from the output port 72 (see Patent Document 1). This water hammer prevention device has a function of absorbing an impact due to pressure fluctuation by expanding and contracting the metal bellows 74 with respect to fluid pressure fluctuation such as water hammer and pulsation generated in the piping line.
Therefore, by installing such a water hammer prevention device on the downstream side of the on-off valve 63 of the chemical solution discharge piping line of the semiconductor cleaning device (see FIG. 10), the metal is prevented from being pushed out due to a sudden closing operation. The bellows 74 is absorbed by contraction, and the chemical liquid can be prevented from jumping out from the discharge portion 65.
Further, the contracted metal bellows 74 extends in reverse with respect to the negative pressure generated thereafter, thereby absorbing energy and preventing air from being sucked from the discharge portion 65.

On the other hand, there is a conventional accumulator as shown in FIG. This accumulator is composed of an upper shell 81 and a lower shell 82, and is composed of a gas chamber 84 partitioned by a diaphragm 83 inside, a shell body 86 having an oil chamber 85, and an oil port 87 communicating with the oil chamber 85. . This accumulator is provided by connecting a plug 88 to a branch portion of a piping line to be controlled (see Patent Document 2).
According to such an accumulator, as in the case of the water hammer prevention device, the diaphragm 83 causes an impact caused by fluid pressure fluctuations such as water hammer, pulsation, and negative pressure caused by the opening / closing operation of the on-off valve 63 installed in the piping line. It can be absorbed by moving up and down.

JP 2006-194367 A JP 2002-372002 A

However, in the above-described water hammer prevention device, since the fluid passes through the side surface of the metal bellows 74 in the center of the flow path, particularly when a slurry is flowed, the gap between the flow path, the internal space 73 and the metal bellows 74 is used. It is easy to stick, and the stuck slurry may interfere with the flow of fluid or cause malfunction.
Further, since the metal bellows 74 is made of metal, it cannot be used in a piping line that uses a highly corrosive chemical solution or a piping line in a semiconductor cleaning apparatus that dislikes elution of metal ions.
The metal bellows 74 can be made of polytetrafluoroethylene (hereinafter referred to as PTFE) or the like that is preferably used as a piping member in a semiconductor manufacturing apparatus. Therefore, it is not suitable for use in a piping line in the field of semiconductor manufacturing that dislikes retention of chemicals. In addition, PTFE bellows have a problem that it is difficult to maintain the initial performance for a long period of time because of the permeation of nitrogen gas.

On the other hand, when the accumulator is installed in the piping line in the semiconductor manufacturing apparatus, the accumulator must be installed by branching along the piping line, and the chemical solution flowing into the oil chamber 85 of the accumulator stays without circulating. Will remain. This is because, in the semiconductor manufacturing field that does not want to stay in the chemical solution, if there is a stagnant part, it causes bacteria, and the bacteria generated in the oil chamber 85 flows into the piping line due to the displacement of the diaphragm 83 and adheres to the semiconductor wafer and is defective. There was a problem that caused
In addition, it is good to always use the same type and concentration of chemicals, but when you want to flow different types of chemicals alternately, such a stagnant part will not completely replace the chemicals. There is a problem that the chemical solution in the oil chamber 85 staying in place due to the displacement of the diaphragm 83 is mixed and the chemical solution inappropriate for the processing of the semiconductor wafer flows to cause defective products.

  The present invention has been made in view of the above problems, and by installing it on the downstream side of the on-off valve of the piping line, even if the on-off valve is suddenly closed, the chemical solution can be ejected from the end of the pipe vigorously. Prevents air from being sucked back from the end of the pipe due to the negative pressure generated downstream when the on-off valve is suddenly closed. And a compact discharge controller.

  In the discharge controller of the present invention, a liquid chamber, a main body having a first flow path and a second flow path respectively communicating with the liquid chamber, an air chamber, and a bonnet having a vent hole communicating with the air chamber; A first feature is that the liquid chamber and the air chamber are provided with a diaphragm having a peripheral portion sandwiched and fixed by the bonnet so as to separate the liquid chamber and the air chamber.

  In the present invention, the lowermost position of the inner diameter of the first flow path and the second flow path is formed so as to be substantially flush with the bottom surface of the liquid chamber having a flat bottom surface. Two features.

  In the present invention, a third feature is that an opening / closing valve is integrally provided in the main body.

  In the present invention, a liquid chamber and a valve chamber are provided, a first flow path communicating with the valve chamber, a second flow path communicating with the liquid chamber, and a communication flow communicating with the liquid chamber and the valve chamber A main body having a passage, a valve body that changes an opening area of the opening of the valve chamber that communicates with the first flow path, a drive unit that drives the valve body, an air chamber, and a communication with the air chamber According to a fourth aspect of the present invention, a bonnet having a vent hole and a diaphragm having a peripheral portion sandwiched and fixed by the bonnet so as to separate the liquid chamber and the air chamber are provided.

  In the present invention, the drive unit includes a motor unit and a stem that moves the valve body up and down by driving the motor unit.

  In the present invention, the drive unit is slidably contacted with a cylinder main body having a cylinder portion therein, in a state of being vertically movable and sealed, and provided at the center of the ceiling surface of the cylinder portion. A piston having a connecting portion that protrudes upward from the center so as to penetrate in a sealed state, and a ceiling surface and an inner peripheral surface of the cylinder portion, The first space portion formed by being surrounded by the upper end surface of the piston and the second space portion formed by being surrounded by the bottom and inner peripheral surfaces of the cylinder portion and the lower end surface of the piston are respectively communicated. A sixth feature is that the valve body is fixed to the upper end of the connecting portion of the piston.

  The seventh feature of the present invention is that a pressure gauge is integrally provided in the main body.

  Furthermore, in the present invention, an eighth feature is that the material of the diaphragm is polytetrafluoroethylene.

  In the present invention, the diaphragms 3, 23, 27 are made of rubber such as ethylene propylene rubber, nitrile rubber, styrene butadiene rubber, fluoro rubber, PTFE, polychlorotrifluoroethylene (hereinafter referred to as PCTFE), polyvinylidene. Fluoride (hereinafter referred to as PVDF), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (hereinafter referred to as PFA), and the like. A fluororesin is preferable, and PTFE is more preferable among the fluororesins.

  Further, in the present invention, the materials of the discharge controller main bodies 1 and 21, the bonnets 2 and 26, the cylinder main body 22, the diaphragm retainer 24, and the piston 25 are not particularly limited as long as they have physical properties necessary as a discharge controller. Fluorine resins such as PTFE, PVDF, PFA, and PCTFE are preferred, and resins such as polypropylene, polyvinyl chloride, polystyrene, and ABS resin, and metals such as stainless steel may be used if there is no concern about corrosion due to fluids. It is not limited.

  The discharge controller of the present invention has the following excellent effects.

(1) Since the chemical solution is prevented from jumping out from the end of the pipe, which is generated when the on-off valve is suddenly closed, it is possible to control the discharge and dripping of a strict amount of the chemical solution. Improve productivity by suppressing the occurrence of
(2) After the on-off valve is suddenly closed, air bubbles are prevented from being caught from the end of the pipe due to the negative pressure in the flow path generated downstream of the on-off valve, and the discharge and dripping of the chemical solution Therefore, productivity can be improved by suppressing the occurrence of defects in the processing of semiconductor wafers.
(3) Since the fluid pressure fluctuation can be suppressed even if the on-off valve is suddenly closed, there is no delay time between the closing signal issued from the control unit such as a semiconductor manufacturing apparatus and the actual on-off valve closing. Further, since the discharge time of the chemical solution can be strictly controlled, it is possible to control the discharge and dropping of the exact amount of the chemical solution, thereby improving the processing performance of the semiconductor wafer.
(4) The first and second flow paths are shaped so that there is little pressure loss, that is, the bottom surface at the lowest position of the inner diameter of the first and second flow paths is substantially flush with the bottom surface of the liquid chamber. Therefore, the flow path is substantially linear, the pressure loss is small, the flow rate is excellent, and the fluid can flow efficiently.
(5) Since there is no stagnant part inside, even when a plurality of chemicals are flowed alternately, the substituting property of the chemicals is good, the generation of bacteria by the stagnant part is prevented, and the slurry adheres even if the slurry is flowed to the fluid. Can be used without clogging.
(6) Since the number of parts is small, it is easy to assemble and can be formed compactly, so that it can be installed without taking the installation place in the apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, it is needless to say that the present invention is not limited to the embodiments.

  FIG. 1 is a longitudinal sectional view showing a discharge controller in a state where a fluid is flowing inside, which is the first embodiment of the present invention, and FIG. 2 shows an on-off valve installed on the upstream side of the discharge controller of FIG. FIG. 3 is a longitudinal sectional view showing a state immediately after the sudden closing, and FIG. 3 is a longitudinal sectional view showing a state in which the downstream side of the on-off valve becomes negative after FIG. FIG. 4 is a schematic piping diagram when the discharge controller of the present invention is installed in a piping line of a semiconductor cleaning device, and FIG. 5 is an enlarged vertical cross-sectional view showing the state of the piping end after the on-off valve is rapidly closed in the piping line of FIG. FIG. FIG. 6 is a longitudinal sectional view showing a discharge controller with an on-off valve according to a second embodiment of the present invention. FIG. 7 is a vertical sectional view taken along line AA of FIG. FIG. 8 is a longitudinal sectional view showing a discharge controller with an on-off valve according to a third embodiment of the present invention. FIG. 9 is a schematic piping diagram showing a test line for a discharge control test.

  1 to 3, the PTFE main body 1 has a substantially mortar-shaped liquid chamber 6 at the center of the upper surface, and a first flow path 4 and a second flow path 5 communicating with the liquid chamber 6 are provided. . At this time, the bottom surface of the liquid chamber 6 is provided flat and is formed so that the lowest positions of the inner diameters of the first flow path 4 and the second flow path 5 are substantially flush with the bottom surface of the liquid chamber 6. The first flow path 4 and the second flow path 5 may be connected to any position of the liquid chamber 6, but are preferably formed on the same axis.

  The bonnet 2 made of PVDF joined to the upper surface of the main body 1 has a substantially mortar-shaped air chamber 7 at the center of the lower surface, and has a φ0.3 mm vent hole 8 for communicating the air chamber 7 with the outside. ing.

  The diaphragm 3 made of PTFE is formed in a disk shape, is a flat and thicker central part, a thin film part extending radially outward from the central part, and a radially outer side from the film part The outer peripheral edge is sandwiched and fixed between the main body 1 and the bonnet 2, and the liquid chamber 6 and the air chamber 7 are isolated by the diaphragm 3. Further, the vicinity of the center of the diaphragm 3 is freely displaceable up and down, and the volume in the liquid chamber 6 is changed by the displacement of the diaphragm 3 according to the fluid pressure inside the liquid chamber 6. At this time, the volume in the air chamber 7 also changes, and air enters and exits from the vent hole 8 provided in the bonnet 2 in accordance with the change in the volume in the air chamber 7.

  Here, it is desirable that the diameter of the vent hole 8 of the bonnet 2 is 0.3 mm to 2.0 mm. In order to prevent the response speed of the displacement from being delayed when the diaphragm 3 moves in the vertical direction, the diameter of the vent hole 8 needs to be 0.3 mm or more, and the pressure fluctuation of the fluid when the diaphragm 3 moves in the vertical direction Accordingly, the diameter of the vent hole 8 needs to be 2.0 mm or less in order to moderate the pressure fluctuation of the fluid by moderately slowing the movement of the diaphragm accordingly. A plurality of vent holes 8 may be provided as long as the total area of the holes is within an area of 2.0 mm in diameter, and a filter may be provided in the vent hole 8.

  Next, the operation of the discharge controller of the first embodiment having the above configuration will be described.

  The discharge controller is used in a chemical supply pipe line of a semiconductor cleaning apparatus as shown in FIG. This piping line is configured such that a fluid flows from the chemical solution tank 11 to the piping 14 by the pump 12 and the chemical solution is discharged from the discharge unit 15 to the semiconductor wafer 16, and a diaphragm type on-off valve 13 driven by air is installed in the piping 14. The discharge controller 17 of the present invention is installed downstream of the on-off valve 13.

  First, when the on-off valve 13 is in an open state, fluid flows through the piping line, and the diaphragm 3 of the discharge controller 17 is slightly displaced upward by the fluid pressure in the liquid chamber 6 (state shown in FIG. 1).

  Here, if the flow of the fluid is suddenly closed by operating the diaphragm type on-off valve 13, piping downstream of the on-off valve 13 is caused by the fluid pushed out by the action of the diaphragm when the on-off valve 13 is closed. The fluid pressure in 14 increases instantaneously. At the same time, the fluid pressure inside the liquid chamber 6 of the discharge controller 17 installed in the pipe 14 also rises. At this time, the diaphragm 3 is displaced upward according to the raised fluid pressure, and the volume of the liquid chamber 6 is increased. This alleviates the increase in fluid pressure (state shown in FIG. 2). As a result, the chemical liquid is prevented from jumping out of the discharge unit 15. Further, as the volume of the liquid chamber 6 increases, the volume of the air chamber 7 decreases and air is discharged from the vent hole 8. The amount of air discharged from the vent hole 8 at this time is determined by the vent hole 8. Since the air volume 7 is restricted, the volume change of the air chamber 7 becomes gradual, and the displacement of the diaphragm 3 can be made gradual, so that rapid pressure fluctuation can be reduced.

  Next, the rapidly closed fluid tends to flow to the discharge portion 15 at the end of the pipe due to the inertia of the flow. Then, a negative pressure is generated in the pipe 14 on the downstream side of the on-off valve 13, and this time a force is applied so that the fluid is pulled back in the reverse direction. At this time, the inside of the liquid chamber 6 of the discharge controller also becomes negative pressure, and the diaphragm 3 that has been displaced upward immediately after the fluid stops is displaced downward to reduce the volume of the liquid chamber 6 to reduce the negative pressure. Cancel (state of FIG. 3). This prevents air from being sucked up from the discharge portion 15 at the end of the pipe and prevents bubbles from entering the chemical solution 18 in the pipe 14 (state shown in FIG. 5). As the volume of the liquid chamber 6 decreases, the volume of the air chamber 7 increases and air is sucked from the vent hole 8. At this time, the amount of air sucked from the vent hole 8 is reduced by the vent hole 8. Due to the restriction, the volume change of the air chamber 7 becomes gradual, the displacement of the diaphragm 3 can be made gradual, and the pressure fluctuation in the pipe caused by the negative pressure can be reduced.

  Even if the on-off valve 13 is suddenly closed by the above operation, the discharge controller 17 absorbs the pressure change in the downstream pipe of the on-off valve 13, so that the chemical solution is vigorous from the discharge part 15 at the end of the pipe 14. It is possible to prevent the air from sucking out from the end portion of the pipe by preventing the air from popping out and then the negative pressure in the pipe. Here, the negative pressure generated after the on-off valve 13 is abruptly closed changes depending on the flow rate of the flowing fluid and the length of the pipe 14, so that the amount of air sucked back also changes, but the size and shape of the diaphragm 3, the vent hole 8 It can be adjusted to be constant by adjusting the diameter. Further, the discharge controller 17 of the present invention has no fluid staying portion in the flow path and the number of parts is very small as three, so that it can be easily assembled and can be made compact. In addition, the first flow path 4 and the second flow path 5 are formed on the same axis, and the position of the bottom of the inner diameter of the flow paths 4 and 5 is designed to be substantially flush with the bottom surface of the liquid chamber 6. Therefore, the flow path is substantially linear, the pressure loss is small, the flow characteristics are excellent, and the fluid in the liquid chamber 6 can flow efficiently. For this reason, it is preferable because the slurry is hard to stick and does not clog even when the slurry is flowed to the fluid. In addition, such an action is particularly useful in the medical field, and when performing a regular drop of a general chemical solution, it is always stable because the fluid is prevented from instantaneously ejecting or sucking in the fluid when the on-off valve is closed. Thus, the fluid can be supplied and a precise amount of dripping can be controlled.

  Next, the discharge controller with on-off valve of the second embodiment will be described.

  6 and 7, in the present embodiment, the main body 21 of the discharge controller is integrally provided with an open / close valve configuration for opening and closing the flow path. The discharge controller includes a discharge controller part formed by the upper part of the main body 21, the diaphragm 27 and the bonnet 26, and an on-off valve part formed by the lower part of the main body 21, the valve body 40 and the drive part 38.

  The PTFE main body 21 has a substantially mortar-shaped liquid chamber 34 at the center of the upper surface, and a second flow path 29 communicating with the liquid chamber 34 is provided. At this time, the bottom surface of the liquid chamber 34 is provided so as to be flat and the lowest position of the inner diameter of the second flow path 29 is substantially flush with the bottom surface of the liquid chamber 34. In addition, a substantially mortar-shaped valve chamber 36 is provided at the center of the lower surface of the main body 21. The bottom of the valve chamber 36 (the ceiling surface in FIGS. 6 and 7) is provided flat, and there is an opening communicating with the first flow path 28 in the center of the bottom, and the periphery of the opening is a valve seat 39. . At this time, the valve seat 39 does not protrude from the opening and is provided at the same height as the bottom of the valve chamber 36. The liquid chamber 34 and the valve chamber 36 are communicated with each other through a communication channel 37. That is, the fluid flowing in from the first flow path 28 flows into the valve chamber 36 through the opening, flows into the liquid chamber 34 through the communication flow path 37, and flows out through the second flow path 29.

  A PVDF bonnet 26 is joined to the upper portion of the main body 21. A substantially mortar-shaped air chamber 33 is provided at the center of the lower surface, and a φ0.3 mm vent hole 35 is formed to communicate the air chamber 33 with the outside.

  The diaphragm 27 made of PTFE is formed in a disk shape, and has a flat central portion formed thicker than the others, a thin membrane portion extending radially outward from the central portion, and a radially outer side from the membrane portion. The outer peripheral edge is sandwiched and fixed between the main body 21 and the bonnet 26, and the diaphragm 27 separates the liquid chamber 34 and the air chamber 33. In addition, the vicinity of the center of the diaphragm 27 can be displaced up and down by the deformation of the film portion, and the volume in the liquid chamber 34 is changed by the displacement of the diaphragm 27 by the fluid pressure inside the liquid chamber 34. At this time, the volume in the air chamber 33 also changes, and air enters and exits from the vent hole 35 provided in the bonnet 26 according to the change in the volume in the air chamber 33.

  The drive unit 38 is used to move the valve body 40 up and down, and is in contact with the lower part of the main body 21 and fixed with bolts and nuts (not shown). The drive unit 38 includes a cylinder body 22, a diaphragm 23, a diaphragm retainer 24, a piston 25, and the like.

  The cylinder body 22 made of PVDF is joined to the lower surface of the body 21, and a cylinder portion 42 in which the later-described piston 25 is accommodated and a step portion 43 in which the later-described diaphragm retainer 24 is accommodated are provided on the cylinder portion 42. . A cylinder portion 42 of the cylinder body 22 is formed by a piston 25, which is surrounded by a lower end surface of a diaphragm retainer 24 serving as a ceiling surface of the cylinder portion 42, an inner peripheral surface of the cylinder portion 42, and an upper end surface of the piston 25 described later. A first air port provided on the side surface of the cylinder body 22 is divided into one space portion, a second space portion formed by being surrounded by the bottom surface and inner peripheral surface of the cylinder portion 42 and the lower end surface of the piston 25. 31 communicates with the first space, and the second air port 32 communicates with the second space.

  The diaphragm 23 made of PTFE is integrally formed with a central valve body 40 and a film portion 41 extending radially on the outer periphery of the valve body 40, and the peripheral portion of the outer periphery of the film portion 41 is formed on the main body 21 and a post-membrane diaphragm presser. 24 is clamped and fixed. The connecting portion 44 of the piston 25 is joined to the lower portion of the valve body 40, and the valve body 40 also moves up and down as the piston 25 moves up and down and is pressed against and separated from the valve seat 39 of the main body 21. Is closed / open.

  The PVDF diaphragm retainer 24 is fitted into a stepped portion 43 at the top of the cylinder body 22, and a through hole 45 through which a connecting portion 44 of the piston 25 described later passes is provided at the center.

  The piston 25 made of PVDF is provided with a disk-like flange portion 46 at the lower portion and a connecting portion 44 that is joined to the diaphragm 23 at the center of the upper surface of the flange portion 46 so as to protrude upward. The flange portion 46 is inserted into the cylinder portion 42 so as to be vertically movable in a sealed state and in the axial direction. Further, the spring 30 is supported between the bottom surface of the flange portion 46 and the bottom surface of the cylinder portion 42. Therefore, the piston 25 is always urged upward by the spring 30. In addition, the connecting portion 44 penetrates the through hole 45 of the diaphragm retainer 24 so as to be movable up and down in the axial direction.

  Operation | movement of the discharge controller with an on-off valve of 2nd embodiment which consists of said structure is demonstrated.

  The discharge controller is used as a chemical solution supply line of a semiconductor cleaning device as shown in FIG. 4, and in this embodiment, the on-off valve 13 and the discharge controller 17 of FIG. . First, when compressed air is injected from the first air port 31 as a working fluid from the outside, the piston 25 is pushed down against the spring 30 by the pressure of the compressed air, so the connecting portion 44 and the upper end portion of the connecting portion 44 are joined. The valve body 40 is also lowered downward, the valve body 40 and the valve seat 39 are separated, the valve is opened, and the fluid flows through the piping line.

  When the injection of the compressed air into the first air port 31 is stopped, the force for pushing the piston 25 downward is lost. As the piston 25 is pushed up by the urging of the spring 30, the connecting body 44 and the valve body 40 joined to the upper end thereof are also pushed up, the valve body 40 is pressed against the valve seat 39, and the valve It will be in a closed state (state of FIG. 6, 7). At this time, since the operation of the discharge controller after the fluid flow is abruptly closed is the same as that of the first embodiment, description thereof is omitted.

In the discharge controller of this embodiment, the discharge controller part and the opening / closing valve part are integrally formed, and the discharge controller is provided immediately downstream of the valve body 40 of the opening / closing valve part for closing and opening the fluid flow. Because of the structure provided, the discharge controller can respond immediately to the closing / opening of the fluid flow by the on-off valve, and the chemical solution from the end of the pipe vigorously due to sudden pressure fluctuations It is possible to effectively prevent the atmospheric air from being sucked out or sucked back from the end of the pipe by negative pressure.
Further, since the two members of the on-off valve 13 and the discharge controller 17 in FIG. 4 can be formed as one valve device, it is preferable because it is compact and the space in the semiconductor cleaning device can be effectively utilized.

  The drive unit of the discharge controller of the present invention may be an electric drive as shown in FIG. 8 instead of an air drive as shown in FIG. In this case, the drive unit 51 includes a motor unit 52 having a stepping motor, and a stem 53 connected to the motor shaft via a gear at a lower portion of the motor unit 52. The stem 53 is disposed so as to be positioned in the through hole 55 of the diaphragm retainer 54. A valve body 56 is screwed to the upper end portion of the stem 53 of the drive unit 51, and the valve body 56 can be moved up and down as the motor unit 52 is driven to move the stem 53 up and down. it can. The valve body 56 may be formed to move up and down by rotating the stem 53.

  The configuration of the on-off valve portion of this embodiment can be any diaphragm valve, stop valve, ball valve, butterfly valve, gate valve, etc. as long as the valve is provided integrally with the main body 21 and can fully open and close the flow path. Although good, particularly in the field of semiconductor manufacturing, a diaphragm valve capable of suppressing the generation of particles is preferable. Since the purpose of the on-off valve portion here is to quickly stop the fluid, the driving method is preferably air driving.

  Moreover, a pressure gauge may be provided integrally with the main body 1 or 21 of the discharge controller of the present invention (not shown), and the pressure change in the flow path can be changed in a compact state without taking up space in the apparatus. In addition to being able to read, pressure may be sensed to enable more stable control.

  Next, the discharge controller of the present invention was prepared, and its performance was evaluated by the following test method.

<Discharge control test>
Using the test line as shown in FIG. 9, the state of the liquid level at the end of the pipe when the air type automatic valve 101 was rapidly closed depending on the presence or absence of the discharge controller 100 was compared. In this test line, a fluid is caused to flow from the chemical solution tank 106 to the piping by the pump 105 and the chemical solution is discharged from the end of the piping. First, the air type automatic valve 101 is opened to allow fluid (water) to flow, and the manual valve 102 on the upstream side and the needle valve 103 on the downstream side are adjusted to set the measured value of the flow meter 104 to a predetermined flow rate. (The flow rate is 2.0 L / min and 3.0 L / min). Next, when the air type automatic valve 101 is rapidly closed, a negative pressure is generated on the downstream side of the air type automatic valve 101 and the air is sucked back from the end of the pipe. The liquid level height h at this time was measured. When there is no liquid remaining in the pipe as shown in FIG. 5, the distance from the end surface of the discharge portion to the liquid level is the liquid level height h, and there is a liquid remaining 69 left partially in the pipe as shown in FIG. In this case, the distance from the end face of the discharge portion to the liquid level when the remaining liquid 69 is removed is defined as a liquid level height h. Further, when there was a liquid residue 69, the number was measured. The piping used for the test was a polyvinyl chloride pipe having a diameter of 25 mm from the tank 106 to the manual valve 102, and thereafter a PFA tube was used. The inner diameter of the PFA tube at the end of the pipe was 3.95 mm.

<Example 1>
The discharge control test was repeated 5 times using the discharge controller shown in FIG. 1 for the discharge controller 100 in the test line of FIG. Table 1 shows the case where the flow rate is 2.0 L / min, and Table 2 shows the case where the flow rate is 3.0 L / min.

<Comparative Example 1>
In the test line of FIG. 9, the discharge control test was repeated five times without the discharge controller 100 being provided. Table 1 shows the case where the flow rate is 2.0 L / min, and Table 2 shows the case where the flow rate is 3.0 L / min.

  From Table 1 and Table 2, when the discharge controller 100 of Example 1 is installed, there is no liquid residue in the end of the pipe, preventing air bubbles from entering the pipe, and the liquid level height h is also stable. You can see that On the other hand, when the discharge controller 100 of Comparative Example 1 is not installed, a liquid residue is generated at the end of the pipe, the liquid level height h is also increased, and the discharge state is not stable. From the above, by installing the discharge controller of the present invention, it is possible to effectively prevent problems at the end of the pipe during fluid discharge. In addition, since the liquid level is stabilized, the amount of fluid discharged can be controlled stably. Therefore, when a general chemical solution is quantitatively discharged or dropped, it is possible to control the dripping of a strict amount of the chemical solution.

It is a longitudinal cross-sectional view which shows the discharge controller of the state which is flowing into the inside which is 1st embodiment of this invention. It is a longitudinal cross-sectional view which shows the state immediately after closing the on-off valve installed in the upstream of the discharge controller of FIG. 1 rapidly. It is a longitudinal cross-sectional view which shows the state by which the downstream of the on-off valve became the negative pressure after FIG. It is piping schematic when the discharge controller of this invention is installed in the piping line of a semiconductor cleaning apparatus. FIG. 5 is an enlarged longitudinal sectional view showing a state of a pipe end after the on-off valve is rapidly closed in the pipe line of FIG. 4. It is a longitudinal cross-sectional view which shows the discharge controller with an on-off valve of 2nd embodiment of this invention. It is an AA longitudinal cross-sectional view of FIG. It is a longitudinal cross-sectional view which shows the discharge controller with an on-off valve of 3rd embodiment of this invention. It is piping schematic which shows the test line of a discharge control test. It is piping schematic of the conventional semiconductor cleaning apparatus. It is a longitudinal cross-sectional view which shows the state of the piping terminal after closing an on-off valve rapidly in the piping line of FIG. It is a longitudinal cross-sectional view which shows an example of the conventional water hammer prevention apparatus. It is a longitudinal cross-sectional view which shows an example of the conventional accumulator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main body 2 Bonnet 3 Diaphragm 4 First flow path 5 Second flow path 6 Liquid chamber 7 Air chamber 8 Vent 21 Main body 22 Cylinder main body 23 Diaphragm 24 Diaphragm retainer 25 Piston 26 Bonnet 27 Diaphragm 28 First flow path 29 Second flow path 30 Spring 31 First air port 32 Second air port 33 Air chamber 34 Liquid chamber 35 Ventilation hole 36 Valve chamber 37 Communication flow path 38 Drive part 39 Valve seat 40 Valve body 42 Cylinder part 44 Connection part 45 Through hole 46 Spear part

Claims (8)

A main body having a liquid chamber and a first flow path and a second flow path respectively communicating with the liquid chamber;
An air chamber, and a bonnet having a vent hole communicating with the air chamber;
A discharge controller comprising: a main body and a diaphragm sandwiched and fixed by a bonnet so as to separate the liquid chamber and the air chamber.   The bottom position of the inner diameter of each of the first channel and the second channel is formed so as to be substantially flush with the bottom surface of the liquid chamber having a flat bottom surface. The discharge controller according to 1.   The discharge controller according to claim 1, wherein an opening / closing valve is integrally provided in the main body. A main body provided with a liquid chamber and a valve chamber, and having a first flow path communicating with the valve chamber, a second flow path communicating with the liquid chamber, and a communication flow path communicating with the liquid chamber and the valve chamber When,
An air chamber, and a bonnet having a vent hole communicating with the air chamber;
A diaphragm having a peripheral edge sandwiched and fixed by the main body and the bonnet so as to separate the liquid chamber and the air chamber;
A valve body for changing an opening area of the opening of the valve chamber communicating with the first flow path;
The discharge controller according to claim 3, further comprising a drive unit that drives the valve body. The drive part seals a cylinder body having a cylinder part inside, a through hole provided in the center of the ceiling surface of the cylinder part in sliding contact with the inner peripheral surface of the cylinder part in a vertically movable and sealed state. A piston having a connecting portion that protrudes upward from the center so as to penetrate in a closed state, a peripheral surface of the cylinder body, a ceiling surface and an inner peripheral surface of the cylinder portion, and an upper end surface of the piston A first space portion formed by being surrounded by, and an air port communicating with the second space portion formed by being surrounded by the bottom surface and the inner peripheral surface of the cylinder portion and the lower end surface of the piston. Equipped,
The discharge controller according to claim 4, wherein the valve body is fixed to an upper end portion of a connecting portion of the piston.   The discharge controller according to claim 4, wherein the driving unit includes a motor unit and a stem that moves the valve body up and down by driving the motor unit.   The discharge controller according to claim 1, wherein a pressure gauge is integrally provided on the main body.   The discharge controller according to any one of claims 1 to 7, wherein a material of the diaphragm is polytetrafluoroethylene.

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