JP2004273830A - Chemical feeder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To measure out a chemical accurately without receiving the effect of bubbles and supply the chemical precisely to a process bath or the like even when supplying the chemical easy to gasify. <P>SOLUTION: According to a chemical feeder to be provided, a bellows pump 3 is set vertically and a discharge port communicating with the top of a pump chamber is formed on the bellows pump 3. The discharge port is connected in a changeover operation to either of a chemical supply pipe 33 supplying the chemical to process sections such as a cleaning bath 1, and a chemical return pipe 34 returning the chemical to a chemical supply tank 2, via electromagnetic opening/closing valves V2, V3. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a chemical solution supply device, and more particularly to a chemical solution supply device used for a semiconductor (Si wafer) cleaning device and a liquid crystal glass substrate cleaning device in a semiconductor manufacturing apparatus.
[0002]
[Prior art]
As a chemical solution supply device used in a cleaning device such as a semiconductor manufacturing process, when a chemical solution is supplied from a chemical solution supply source to a processing tank (cleaning tank) by a pump, processing is performed by supplying a chemical solution containing no air bubbles to the processing tank. There is an apparatus in which the supply amount of a chemical solution supplied to a tank does not cause an error due to the incorporation of bubbles (for example, Patent Document 1).
[0003]
An outline of this chemical solution supply device will be described with reference to FIG. The supply and replenishment of the chemical solution to the processing tank 100 is performed by driving a pump 102 provided in a lower pipe of a chemical solution supply tank (chemical solution supply source) 101 and opening a valve 103. At this time, the pump 102 used is an air-driven diaphragm pump, an electric-driven bellows pump, or a type in which the inside of the container is pressurized with an inert gas such as nitrogen to push out a chemical solution.
[0004]
A mixture of ammonia, hydrogen peroxide, and water is often used as a chemical for cleaning semiconductor wafers and liquid crystal glass, but this chemical is easily vaporized. For this reason, bubbles are generated in the pump and the piping, and it is not possible to discharge an accurate amount when discharging the chemical solution.
[0005]
For this reason, the pipe at the pump outlet is branched at a branch point 104 into a treatment tank 100 and a chemical supply tank 101, and the flow of the chemical is switched by valves 103 and 105, respectively.
[0006]
In the initial step of supplying the chemical, by opening the valve 105 on the chemical supply tank 101 side and closing the valve 103 on the processing tank 100, the pump 102 is driven, and the chemical is returned to the supply tank 101 and circulated. , Air bubbles in the piping are removed.
[0007]
After that, the valve 105 on the side of the chemical solution supply tank 101 is closed, and then, with the valve 103 on the side of the processing tank 100 being opened, the pump 102 is driven to supply a chemical solution to the processing tank 100, so that Air bubbles are reduced in the supplied chemical solution.
[0008]
[Patent Document 1]
Japanese Patent No. 3341206
[Problems to be solved by the invention]
However, in the conventional chemical liquid supply device as described above, not only can air bubbles in the piping be completely eliminated, but air-driven diaphragm pumps are liable to generate air bubbles. Bubbles may not disappear. Therefore, the supply amount of the chemical solution supplied to the processing tank is not stable, the concentration of the chemical solution in the processing tank is not stable, the concentration cannot be set with high accuracy, and the cleaning state is not stable.
[0010]
The present invention has been made in order to solve the above-described problems, and even when supplying a chemical solution that is easy to vaporize, a chemical solution that accurately weighs without being affected by air bubbles and accurately supplies the chemical solution to a processing tank or the like. It is intended to provide a supply device.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, a chemical solution supply device according to the present invention is a chemical solution supply device that sucks a chemical solution from a chemical solution supply tank and supplies it to a processing unit, wherein a pump chamber in which a chemical solution is sucked from the chemical solution supply tank, A reciprocating pump such as an electric bellows pump for sucking a chemical solution from the chemical solution supply tank into the pump chamber, a discharge port for chemical solution discharge communicating with the upper part of the pump chamber, and a chemical solution return for returning the chemical solution to the chemical solution supply tank. A flow path switching means for switching and connecting the discharge port to one of a passage and a chemical solution supply passage for supplying a chemical solution to the processing section is provided.
[0012]
ADVANTAGE OF THE INVENTION According to the chemical | medical solution supply apparatus by this invention, since the discharge port of the reciprocating pump was made into the upper part of a pump room, air bubbles and gas can be collected in the upper part of a pump room, and the gas (bubble) in a chemical solution becomes upper part of a pump room. The collected gas is subjected to gas-liquid separation, and the gas collected in the upper part of the pump chamber can be forcibly released to the side of the chemical solution supply tank by the discharge operation of the reciprocating pump, and the fluid discharged from the reciprocating pump does not contain bubbles. After the state of the complete liquid phase is reached, the chemical solution can be supplied to a processing unit such as a cleaning tank.
[0013]
The chemical liquid supply device according to the present invention further includes gas-liquid detection means for detecting whether the fluid discharged from the discharge port is a non-liquid phase containing gas or a liquid phase containing no gas, and the flow path The switching unit connects the discharge port to the chemical liquid return passage when the gas-liquid detection unit detects the non-liquid phase, and connects the discharge port to the chemical liquid supply when the liquid phase is detected. Connect to passage.
[0014]
According to the chemical liquid supply device of the present invention, whether the fluid discharged from the discharge port of the reciprocating pump is a non-liquid phase containing gas or a liquid phase containing no gas is monitored by the gas-liquid detection means, While the detection means detects the non-liquid phase, the discharge port is connected to the chemical liquid return passage to allow gas or a chemical liquid containing gas (gas-liquid mixture) to escape to the chemical liquid supply tank side. When a liquid phase is detected by the liquid detecting means, the discharge port is connected to a chemical liquid supply passage, so that only a complete liquid phase chemical liquid containing no bubbles is supplied to a processing unit such as a cleaning tank. Can be.
[0015]
The liquid medicine supply device according to the present invention further has a position detecting means for detecting a piston movement position of the reciprocating pump, and is in a liquid phase from a state in which a non-liquid phase is detected by the gas-liquid detecting means. The amount of the discharged chemical liquid is controlled on the basis of the piston movement position detected by the position detecting means at the time when the state changes to the state in which the detection is made.
[0016]
According to the chemical liquid supply apparatus of the present invention, the position detection means monitors the piston movement position of the reciprocating pump, and detects that the fluid discharged from the discharge port of the reciprocating pump is in a non-liquid phase by the gas-liquid detection means. By controlling the amount of the discharged chemical liquid based on the piston movement position at the time when the liquid state is changed from the state in which the liquid phase is detected to the state in which the liquid phase is detected, the optimum supply amount of the chemical liquid is controlled by a processing unit such as a cleaning tank. Can be accurately supplied to
[0017]
In addition, the reciprocating pump in the chemical solution supply device according to the present invention may be arranged vertically below the pump chamber, and the piston may reciprocate vertically.
[0018]
The chemical solution supply device according to the present invention further includes a dilution water supply system that supplies dilution water such as pure water to the cleaning tank, and a concentration detection unit that detects a concentration of the chemical solution in the cleaning tank. The supply amount of the chemical solution from the chemical solution supply tank to the cleaning tank by the reciprocating pump according to the chemical solution concentration of the cleaning tank detected by the detection means, and the dilution water supplied to the cleaning tank by the dilution water supply system. Control the supply.
[0019]
According to the chemical solution supply device of the present invention, the concentration of the chemical solution in the cleaning tank is detected by the concentration detecting means, and based on this, the supply amount of the chemical solution supplied from the chemical solution supply tank to the cleaning tank by the reciprocating pump, and the dilution water supply Since the supply amount of the dilution water to be supplied to the cleaning tank is controlled by the system, the chemical concentration in the cleaning tank can be automatically set to the target value.
[0020]
The chemical supply apparatus according to the present invention further includes a tank solution circulation system for circulating the solution in the cleaning tank, and can uniform the concentration of the chemical in the cleaning tank.
[0021]
The chemical solution supply device according to the present invention further includes a solution discharge passage for discharging the solution in the washing tank, and a specific resistance detecting unit for detecting the specific resistance of the solution flowing through the solution discharge passage.
[0022]
ADVANTAGE OF THE INVENTION According to the chemical | medical solution supply apparatus by this invention, in the completion | finish process of washing | cleaning by a chemical | medical solution, when supplying only the diluting liquid by pure water etc. to a washing tank and lowering the chemical | medical solution density | concentration of a washing tank, supply of the diluting liquid with respect to a washing tank is needed. At the same time, the solution in the washing tank is discharged from the solution discharge passage, and the specific resistance of the solution flowing through the solution discharge passage is monitored by the specific resistance detecting means. The completion of the cleaning can be confirmed by the fact that the specific resistance of the discharged solution detected by the specific resistance detecting means is equal to that of the diluent.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 shows an embodiment in which the chemical solution supply device according to the present invention is used in a Si wafer cleaning device.
[0024]
There are mainly two types of Si wafer cleaning apparatuses. One of them is a so-called batch type cleaning apparatus in which a chemical cleaning tank is separately provided depending on a type of a chemical used for cleaning, and Si wafers are sequentially taken in and out of the various cleaning tanks by a cleaning process. The other is a so-called one-bath type cleaning apparatus in which a Si wafer does not move in one cleaning tank and chemicals are replaced one after another.
[0025]
The chemical cleaning apparatus of the present invention is an effective system for both types of cleaning. Further, the supply of the chemical solution to the cleaning tank may be performed in a case where all the chemical solutions in the cleaning tank are replaced, or in a case where an insufficient chemical solution is supplied in order to stabilize the concentration of the chemical solution in the cleaning tank. The chemical liquid cleaning device of the present invention is a system effective for either of them.
[0026]
The Si wafer cleaning apparatus includes a cleaning tank 1 for accommodating a Si wafer W, a chemical supply tank 2 for storing a cleaning chemical, for example, a chemical for cleaning with hydrofluoric acid (hydrofluoric acid), and a chemical for the chemical supply tank 2. And an electric bellows pump 3 which is a reciprocating pump for supplying the cleaning tank 1 with the water.
[0027]
The electric bellows pump 3 is placed vertically, and the pump stroke direction is vertical as shown in FIG. The electric bellows pump 3 has a cylindrical pump housing 5 including a pump head 4, an airtight plate 8 attached to a lower part of the pump housing 5 by a connecting member 6 and defining a machine chamber 7, and a housing 9. .
[0028]
A bellows 11 is provided in a cylinder bore 10 of the pump housing 5 so as to be able to expand and contract in the axial direction (vertical direction). The bellows 11 includes an expandable cylindrical thin-walled bellows wall portion 11A, a movable piston portion 11B having an end wall shape that closes the upper end of the bellows wall portion 11A, and an annular fixing provided at a lower end of the bellows wall portion 11A. The ring portion 11C is integrally formed of a fluorine-based resin such as polytetrafluoroethylene (PTFE).
[0029]
The pump housing 5 and the bellows 11 define a pump chamber 12 between the pump head part 4 and the movable piston part 11B. The pump housing 5 has a suction port 13 communicating with a lower region of the pump chamber 12 and a discharge port 14 communicating with the uppermost part of the pump chamber 12. The upper part of the pump chamber 12 has a conical shape, and a discharge port 14 is opened at the uppermost part in the center. The upper surface of the movable piston portion 11B also has a conical shape following the upper conical shape of the pump chamber 12.
[0030]
The fixing ring portion 11C of the bellows 11 is sandwiched between the pump housing 5 and the airtight plate 8, and is airtightly fixed to the pump housing 5 side. The airtight plate 8 is formed with a ventilation passage 16 in the bellows internal space 15 and a liquid leak detection passage 17. A bellows internal space vent member 18 and a liquid leak detector 19 are attached to the airtight plate 8.
[0031]
The upper end of the bellows drive shaft 20 is fixedly connected to the center of the rear side of the movable piston portion 11B of the bellows 11. The bellows drive shaft 20 protrudes into the machine room 7 through a through hole 21 formed in the airtight plate 8.
[0032]
In the machine room 7, a pulse motor 22 and a ball screw device 23 driven by the pulse motor 22 are provided, and a screw shaft 24 of the ball screw device 23 and the bellows drive shaft 20 are coaxially connected. The screw shaft 24 moves in the axial direction by driving a motor, and drives the bellows drive shaft 20 in the axial direction (pump stroke direction = vertical direction) in a directly connected state. A rotary encoder 25 serving as a position detector is connected to the pulse motor 22.
[0033]
In the bellows pump 3, the movable piston portion 11B of the bellows 11 moves downward by the downward movement (suction stroke) of the bellows drive shaft 20, and a fluid such as a chemical solution flows into the pump chamber 12 from the suction port 13 as the bellows 11 contracts. When the bellows drive shaft 20 moves upward (discharge stroke), the movable piston portion 11B of the bellows 11 rises and discharges the fluid in the pump chamber 12 to the discharge port 14 as the bellows 11 expands.
[0034]
The amount of suction and discharge of the bellows pump 3 can be quantitatively variably set by the amount of movement of the movable piston portion 11B in the axial direction, in other words, the amount of drive of the bellows drive shaft 20 by the ball screw device 23. The moving position of the movable piston portion 11B in the axial direction is detected by the rotary encoder 25.
[0035]
The machine room 7 is provided with a photoelectric type home sensor 26. Further, the housing 9 is provided with a machine room ventilation port member 27, a machine room pressure relief valve 28, and the like.
[0036]
The suction port 13 of the bellows pump 3 is connected to the bottom of the chemical supply tank 2 by a suction pipe 31. An electromagnetic opening / closing valve V1 (see FIG. 1) for inhaling a chemical is attached to the suction pipe 31. A discharge pipe 32 is connected to the discharge port 14 of the bellows pump 3. As shown in FIG. 1, the discharge pipe 32 is branched into two branches, one of which is connected to an electromagnetic opening / closing valve V2 for discharging a chemical liquid and the liquid supply pipe 33, and the other is an electromagnetic opening / closing valve V3 for discharging bubbles. , And a chemical solution return pipe 34.
[0037]
The electromagnetic on-off valves V2 and V3 open and close in an opposite relationship to each other, and form a flow path switching unit that switches and connects the discharge port 14 of the bellows pump 3 to one of the chemical supply pipe 33 and the chemical return pipe 34.
[0038]
The chemical supply pipe 33 is connected to the cleaning tank 1 by a supply pipe 35, and the chemical return pipe 34 is connected to the upper part of the chemical supply tank 2 via a filter 36.
[0039]
A gas-liquid sensor 37 is provided at the electromagnetic switching valve V3 of the discharge pipe 32. The gas-liquid sensor 37 is of a photoelectric type or an ultrasonic type, and detects whether the fluid discharged from the discharge port 14 is a non-liquid phase containing a gas or a liquid phase containing no gas (bubbles). .
[0040]
A pure water supply pipe 38 is connected to the supply pipe 35 as a dilution water supply system, and pure water is weighed and supplied from a pure water supply source 39 by opening and closing an electromagnetic opening and closing valve V7.
[0041]
The washing tank 1 is provided with an overflow tank 40. The overflow tank 40 and the supply pipe 35 are connected by a circulation pipe 44 to form a tank solution circulation system. In the middle of the circulation pipe 44, an electromagnetic on-off valve V4, a concentration sensor 41, a circulation pump 42, a filter 43 is provided. The concentration sensor 41 detects the concentration of the chemical in the cleaning tank 1 in the circulation pipe 44.
[0042]
Further, a solution discharge pipe 45 is connected to the overflow tank 40. An electromagnetic opening / closing valve V5 and a specific resistance sensor 46 are connected to the solution discharge pipe 45. The specific resistance sensor 46 measures and detects the specific resistance of the solution flowing through the solution discharge pipe 45. The cleaning tank 1 has a hopper tank shape, and a waste liquid pipe 47 and an electromagnetic valve V6 are connected to the bottom.
[0043]
Each sensor output of the gas-liquid sensor 37, the concentration sensor 41, and the specific resistance sensor 46 is input to the control device 50. The control device 50 is a computer type, and controls the electromagnetic opening and closing valves V1 to V4 according to the sensor outputs from the rotary encoder 25, the gas-liquid sensor 37, the concentration sensor 41, and the specific resistance sensor 46 and the command signal from the operation panel 51. The opening and closing of V7 and the operation (drive) of the bellows pump 3 and the circulation pump 42 are controlled.
[0044]
The controller 50 basically opens the electromagnetic valve V3 when the gas-liquid sensor 37 detects that the fluid discharged from the discharge port 14 of the bellows pump 3 is a non-liquid phase containing gas. When the gas-liquid sensor 37 detects that the fluid discharged from the discharge port 14 of the bellows pump 3 is a liquid phase containing no gas, the electromagnetic valve V3 is closed and the electromagnetic valve V3 is closed. Control for opening the on-off valve V2 is performed.
[0045]
Next, an operation based on a usage example in hydrofluoric acid cleaning will be described with reference to a time chart shown in FIG.
(1) At the start, the control device 50 closes the electromagnetic opening and closing valve V3 and the electromagnetic opening and closing valve V2, and opens the electromagnetic opening and closing valve V1, and in this state, causes the bellows pump 3 to perform a suction operation. Thus, the hydrofluoric acid solution is sucked into the pump chamber 12 of the bellows pump 3 from the chemical solution supply tank 2 containing the hydrofluoric acid solution.
[0046]
In the initial state, the pump chamber 12 is empty and the piping is also empty. Therefore, when the hydrofluoric acid solution is sucked into the bellows pump 3 from the chemical solution supply tank 2, a lot of air or partially vaporized hydrofluoric acid is used. The liquid accumulates in the upper part of the pump chamber 12.
[0047]
(2) Next, the electromagnetic switching valve V2 and the electromagnetic switching valve V1 are closed, the electromagnetic switching valve V3 is opened, and the bellows pump 3 is discharged in this state. The gas accumulated in the upper part of the pump chamber 12 passes through the electromagnetic opening / closing valve V3 through the gas-liquid sensor 37 from the discharge port 14 at the uppermost part of the pump chamber by the discharge operation of the bellows pump 3, and further passes through the filter 36 to the chemical liquid supply tank. Return to 2.
[0048]
Instead of the path from the electromagnetic on-off valve V3 to the chemical supply tank 2 via the chemical liquid return pipe 34 and the filter 36, a path from the electromagnetic on-off valve V3 to the waste liquid tank 49 via the waste liquid pipe 48 is provided. The gas collected in the upper part of the chamber 12 may be returned to the waste liquid tank 49.
[0049]
(3) Further, when the bellows pump 3 is operated to discharge, all gas in the upper part of the pump chamber is discharged, and the inside of the pump chamber 12 is completely filled with hydrofluoric acid solution. Eventually, the pipe above the pump (discharge pipe 32) is also filled with the hydrofluoric acid solution. When the gas-liquid sensor 37 detects that the piping above the pump is completely filled with hydrofluoric acid, the control device 50 stops the bellows pump 3 by a signal from the gas-liquid sensor 37, Close V3.
[0050]
(4) In the initial state, if a large amount of gas is present in the pump chamber 12 or in the piping, a sufficient amount of liquid may not be secured after the gas in the pump chamber 12 is pushed out. Since the control device 50 constantly monitors the bellows position of the bellows pump 3 (the moving position of the movable piston portion 11B), the amount of liquid that can be discharged can be obtained from the gas extrusion completion position, and a sufficient discharge can be obtained. If the amount cannot be secured, the pump chamber 12 can be filled up by repeating the suction steps (1) to (3) again, and a sufficient discharge amount can be secured.
[0051]
If the pump chamber 12 cannot be fully filled even if the suction process is repeated several times, the chemical solution supply tank 2 may be empty, the pipe may be disconnected or leaked, or other abnormalities may occur. It is also possible to issue an abnormal alarm.
[0052]
(5) Normally, once the inside of the pump chamber 12 and the inside of the pipe are filled with the chemical solution, the amount of gas accumulated in the upper part of the pump chamber is not large. Is detected by the rotary encoder 25 at a point in time when it is detected that the liquid phase is satisfied, that is, when a state in which the gas-liquid sensor 37 detects the non-liquid phase changes to a state in which the liquid phase is detected. The discharged chemical liquid amount is controlled based on the detected piston movement position.
[0053]
That is, based on the piston movement position and the required discharge amount stored in the control device 50 at the time when the gas-liquid sensor 37 detects that the piping above the pump is completely filled with the hydrofluoric acid solution, the bellows pump 3 The operation stroke is determined. Also, the discharge amount per time can be accurately determined by determining the operation speed of the bellows pump 3.
[0054]
(6) At the start, at the same time as the operation of (1), the electromagnetic opening / closing valve V7 is opened, and a predetermined flow of pure water is injected into the cleaning tank 1 from the pure water supply source 39.
(7) When the cleaning tank 1 is filled with pure water, a plurality of (normally 25 cassettes) Si wafers W in the wafer cassette 52 are put into the cleaning tank 1.
[0055]
(8) Next, the electromagnetic switching valve V4 is opened, the circulation pump 42 is driven, and the liquid in the cleaning tank 1 circulates.
(9) In this state, when a predetermined amount of hydrofluoric acid solution is discharged at a predetermined flow rate by the bellows pump 3 through the electromagnetic opening / closing valve V2, the hydrofluoric acid concentration in the cleaning tank 1 gradually increases, and finally, To a predetermined hydrofluoric acid concentration.
[0056]
(10) Since the concentration of hydrofluoric acid in the cleaning tank 1 is monitored by the optical concentration sensor 41, when the concentration of hydrofluoric acid in the cleaning tank 1 is not at a predetermined concentration or when the concentration of hydrofluoric acid changes, pure water is used. Replenishment or replenishment of chemicals may be performed.
[0057]
(11) When the cleaning with the hydrofluoric acid solution is performed for a predetermined time, the electromagnetic opening and closing valve V5 opens, and at the same time, the electromagnetic opening and closing valve V7 opens, and pure water is injected into the cleaning tank 1. As a result, the cleaning liquid overflowing into the overflow tank 40 is drained from the solution discharge pipe 45, and the concentration of the hydrofluoric acid in the cleaning tank 1 gradually decreases.
[0058]
(12) At this time, the specific resistance of the solution discharged from the cleaning tank 1 is measured by a specific resistance sensor 46 attached to the solution discharge pipe 45 of the cleaning tank 1, and the concentration of the liquid in the cleaning tank 1 is measured by a decrease in the concentration of hydrofluoric acid. It is confirmed that the cleaning has been completed when the specific resistance reaches the same value as the specific resistance of the pure water injected. Thus, the cleaning of the Si wafer W with the hydrofluoric acid solution is completed, and the Si wafer W is carried out of the cleaning tank 1. Thereafter, the electromagnetic opening / closing valve V6 is opened to discharge the liquid in the cleaning tank 1.
[0059]
This cleaning step is an example for explaining the chemical solution supply device of the present invention, and the method of using the chemical solution supply device is not limited to this. The chemical liquid supply device is also effective for chemical liquids other than the hydrofluoric acid liquid, and is particularly effective for liquids that are easily vaporized, such as ammonia and hydrogen peroxide.
[0060]
In the above-described embodiment, a vertically mounted bellows pump 3 that vertically moves the pump stroke direction by vertically moving the movable piston portion 11B by expansion and contraction of the bellows 11 to suck and discharge a fluid such as a chemical solution is used. Although the case has been described, the reciprocating pump for sucking and discharging a fluid such as a chemical solution may be of a type other than the bellows pump.
[0061]
In addition, the arrangement of the reciprocating pump is not limited to the vertical setting, and may be a horizontal setting. Similarly, the pump stroke due to the reciprocating motion of the piston may be not the vertical direction but the horizontal direction. Any structure, arrangement, and pump stroke direction may be used as the reciprocating pump as long as gas (bubbles) in a fluid such as a chemical solution in the pump housing is configured to accumulate in the upper part of the pump housing. That is, of course.
[0062]
【The invention's effect】
As understood from the above description, according to the chemical solution supply device of the present invention, the discharge port of the reciprocating pump is located at the upper part of the pump chamber, so that the bubbles can be collected at the upper part of the pump chamber, and the discharge of the bubbles can be easily performed. It is possible to accurately measure and supply even a chemical solution that is easily vaporized without being affected by bubbles to a processing unit such as a cleaning tank.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram showing one embodiment in which a chemical liquid supply device according to the present invention is used in a Si wafer cleaning device.
FIG. 2 is a sectional view showing one embodiment of a bellows pump used in the chemical solution supply device according to the present invention.
FIG. 3 is a time chart of one embodiment in which the chemical solution supply device according to the present invention is used in a Si wafer cleaning device.
FIG. 4 is a system configuration diagram showing a conventional chemical solution supply device.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 Cleaning tank 2 Chemical supply tank 3 Bellows pump 11 Bellows 12 Pump chamber 14 Discharge port 22 Pulse motor 25 Rotary encoder 33 Chemical supply pipe 34 Chemical return pipe 37 Gas-liquid sensor 39 Pure water supply source 41 Concentration sensor 44 Circulation pipe 45 Solution Discharge pipe 46 Specific resistance sensor 50 Controller V1 to V7 Electromagnetic open / close valve

Claims (9)

In a chemical liquid supply device that sucks a chemical liquid from a chemical liquid supply tank and supplies it to the processing unit,
A pump chamber into which a chemical is sucked from the chemical supply tank;
A reciprocating pump that sucks a drug solution from the drug solution supply tank into the pump chamber;
A discharge port for discharging a chemical solution communicating with the upper part of the pump chamber,
A chemical liquid return passage that returns a chemical liquid to the chemical liquid supply tank, and a flow path switching unit that switches and connects the discharge port to one of a chemical liquid supply path that supplies a chemical liquid to the processing unit;
A chemical solution supply device comprising: Gas-liquid detection means for detecting whether the fluid discharged from the discharge port is a non-liquid phase containing gas or a liquid phase containing no gas,
The flow path switching means connects the discharge port to the chemical liquid return passage when the gas-liquid detection means detects a non-liquid phase, and connects the discharge port when the liquid phase is detected. The chemical solution supply device according to claim 1, wherein the chemical solution supply device is connected to the chemical solution supply passage. Having position detection means for detecting a piston movement position of the reciprocating pump,
At the time when the state where the gas-liquid detecting means detects the non-liquid phase is changed to the state where the liquid phase is detected, the discharged chemical liquid is based on the piston movement position detected by the position detecting means. 3. The chemical supply device according to claim 2, wherein the amount is controlled. The chemical solution supply device according to any one of claims 1 to 3, wherein the reciprocating pump is vertically disposed below the pump chamber, and a piston reciprocates in a vertical direction. The said reciprocating pump is an electric bellows pump, The chemical | medical solution supply apparatus as described in any one of Claims 1-4 characterized by the above-mentioned. The chemical solution supply device according to any one of claims 1 to 5, wherein the processing unit is a cleaning tank using a chemical solution. A dilution water supply system that supplies dilution water to the cleaning tank, and a concentration detection unit that detects a concentration of a chemical solution in the cleaning tank,
The supply amount of the chemical solution from the chemical solution supply tank to the cleaning tank by the reciprocating pump according to the chemical solution concentration of the cleaning tank detected by the concentration detection means, and the dilution supplied to the cleaning tank by the dilution water supply system. 7. The chemical supply device according to claim 6, wherein the supply amount of water is controlled. The chemical solution supply device according to claim 6, further comprising a tank solution circulation system that circulates the solution in the cleaning tank. The chemical solution according to any one of claims 6 to 8, further comprising a solution discharge passage for discharging the solution in the washing tank, and a specific resistance detecting unit configured to detect a specific resistance of the solution flowing through the solution discharge passage. Feeding device.

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