JPH11117872A - Tube pump system for transferring slurry liquid - Google Patents

Abstract

(57) [Problem] To provide a tube pump system having a long life characteristic without performance deterioration due to stagnation of a slurry liquid and particularly useful when applied to CMP technology. A pump unit includes a pair of pump bodies having a flexible tube as a diaphragm, and an actuator for driving the pump bodies alternately. Damper 200 connected to pump unit 100
Has a structure similar to that of the pump bodies 1 and 2 using a flexible tube. Pump unit 100 and damper 200
And are placed inline. Each pump body 1, 2
A cylindrical body having a cylindrical space 12 therein; a flexible tube coaxially disposed in the cylindrical space of the cylindrical body and having a passage for a slurry liquid to be transferred inside and a working fluid space on the outside; A check valve attached to both ends of the tubular body so as to be connected to both ends of the flexible tube, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pump system suitable for liquid transfer, and more particularly to a tube pump using a tubular diaphragm pump applied to transfer of a CMP slurry liquid used for flattening the surface of LSI devices and the like. About the system.

[0002]

2. Description of the Related Art In recent years, the density of LSI devices, the miniaturization of elements and wirings, and the multilayering of wirings have been increasingly advanced.
For this reason, planarization technology for LSI devices has become important, and so-called CMP (Chemical Mechanical Polishing) technology for planarizing the wafer surface using a slurry liquid has attracted attention. The slurry liquid (CMP liquid) is selected according to the object to be polished. For example, when an insulating film such as SiO ₂ is used, silica-based particles are used as particles of the slurry liquid, and when a metal film such as Al is used, alumina particles are used.

A bellows type pump as shown in FIG. 7 is conventionally known as a liquid transfer pump used in such a CMP technique. One end of each of the two pump chambers 41a, 41b is commonly connected to a liquid suction port 42 via a check valve 45a, 45b, and the other end is similarly a common discharge port 43 via a check valve 44a, 44b. It is connected to. Movable ends 46a and 46b for alternately increasing and decreasing the pressure in the pump chambers 41a and 41b are supported by bellows 47a and 47b, respectively, and air supply chambers 48a and 48b to which air serving as working gas is supplied behind the movable ends 46a and 46b.
Are formed. These air supply chambers 48a, 48b
, The two pump chambers 41a and 41b alternately alternately suck and discharge the liquid.

The liquid discharged from the common discharge port 43 includes a pulsation because the pump chambers 41a and 41b are driven alternately. In order to reduce the pulsation and obtain a flow rate as constant as possible, a pipe connected to the discharge port 43 is usually provided with a damper. FIG. 8 shows an example of the structure of such a damper. Piping 5 connected to discharge port 43
0, and a damper chamber 53 connected to the pipe section 51. The damper chamber 53 has a lid 54 with a gas supply port 55 opened. Rubber damper 5 for shock absorption connected to gas supply port 55
2 (may be a bellows type damper). The pressure fluctuation in the pipe 50 is absorbed by the damper 52 in the damper chamber 53. Back pressure for adjusting the absorption characteristics, by adjusting the supply pressure, such as N ₂ gas or compressed air, can be set to an appropriate value.

FIG. 9 shows a configuration example of a tube pump (roller pump) using a mechanical drive system. This pump is provided around a cylindrical body 61 which is rotationally driven, in the example shown in FIG.
Rollers 62 are provided at 0 ° intervals, and a flexible tube 63 for transferring a liquid is stretched over these rollers 62. With such a configuration, by rotating and driving the cylindrical body 61, the flexible tube 63 can transfer the liquid according to the same principle as peristalsis.

[0006]

When the bellows type pump shown in FIG. 7 is used for transferring a CMP liquid in which particles are dispersed, the CMP liquid stays in the folds of the bellows 47a and 47b, and the particles settle. This causes a problem that the pump performance is deteriorated. Similarly, the damper shown in FIG.
3 gradually accumulates and accumulates particles, resulting in a shortened life. The tube pump shown in FIG. 9 has an advantage that particles hardly accumulate even when used for transferring a CMP solution. On the other hand, although the mechanical deformation of the flexible tube 63 is averaged in a certain time range, it is locally large instantaneously, so that the flexible tube 63 is rapidly deteriorated, and its life is shortened. Also, the discharge flow rate decreases. In addition, since the tube is of a very large type, there is also a problem that dust is generated in the transfer liquid.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a tube pump system having a long life characteristic without deterioration in performance due to stagnation of a slurry liquid, and particularly useful for application to CMP technology. It is an object.

[0008]

A pump system for transferring a slurry liquid according to the present invention sucks and transfers a slurry liquid, which comprises a pair of columnar pump bodies connected in parallel and an actuator for alternately driving these. A pump unit and a columnar damper connected in-line to the pump unit to attenuate the pulsation of the slurry liquid sucked up by the pump unit. Each of the columnar pump bodies has a cylindrical space inside. A first cylindrical body having one end as a suction port and the other end as a discharge port, and a pump coaxially arranged in the columnar space of the first cylindrical body and through which the slurry liquid passes. A first flexible tube which is a chamber and whose outside is a working fluid space in which a working fluid is sealed, and which is attached to both ends of the first cylindrical body and has a first flexibility; A check valve connected to both ends of the tube, wherein the columnar damper has a columnar space formed therein, one end of which is connected to the pump unit at the suction port, and the other end of which is connected to the pipe. A second cylindrical body serving as a discharge port, and a second cylindrical body disposed coaxially with the cylindrical space of the second cylindrical body, the inside of which is a passage through which the slurry liquid to be transferred passes and the outside of which is a working fluid space. And two flexible tubes.

Preferably, in the present invention, the actuator comprises: a pair of cylinders each having an opening connected to a working fluid space of each columnar pump body; a piston or a bellows reciprocally arranged in each cylinder;
The piston or bellows is of a double-acting type having a gas drive chamber driven by compressed gas. Further, in the present invention, a type selected from fluorine oil, water and ethylene glycol is sealed in the working fluid space of each columnar pump body and each cylinder of the actuator, and a compressed gas is supplied to the working fluid space of the damper. .

Further, in the present invention, preferably, the pair of cylinders of the actuator are arranged symmetrically with respect to the gas drive chamber. Specifically, for example, the actuator is formed in a column shape in which a pair of cylinders are arranged vertically above and below the gas drive chamber, and the actuator is aligned with the pump unit such that the side surface contacts the side surface of each columnar pump body.
Alternatively, the actuator may be disposed separately from the pump unit, and may be connected to the pump unit by a transparent resin pipe filled with a working fluid. In this case, a photo sensor for monitoring the turbidity inside the transparent resin pipe and detecting leakage of the slurry liquid of the pump unit can be provided.

[0011] A tube pump system for transferring a slurry liquid according to the present invention further comprises a pump unit for sucking and transferring the slurry liquid, comprising a pair of columnar pump bodies connected in parallel and an actuator for alternately driving them. And a columnar damper connected to the pump unit in-line to attenuate pulsation of the slurry liquid sucked up by the pump unit,
The columnar damper has a columnar space formed therein,
A cylindrical body having one end connected to the pump unit and a discharge port connected to the pipe at the other end, and a slurry which is coaxially arranged in the cylindrical space of the cylindrical body and has the inside to be transferred; And a flexible tube having a passage through which the liquid passes and a working fluid space on the outside.

In the pump system according to the present invention, the pump unit is constituted by a pair of columnar tube pumps using a flexible tube, and the damper connected to the pump unit is the same as the tube pump using the flexible tube. It has a columnar structure. The pump unit and the damper are arranged in-line, and the slurry liquid is transferred at a constant flow rate without pulsation by alternately driving a pair of tube pumps and the action of the damper. Therefore,
In the pump system according to the present invention, there is no place in the slurry liquid transfer path where the slurry liquid stays or the particles settle out, whereby a long-life slurry liquid transfer system with no performance deterioration can be obtained.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a pump system for transferring a slurry liquid according to an embodiment of the present invention. In this embodiment, the pump unit 100 includes a pair of columnar pump bodies 1 and 2 connected in parallel, and an actuator 3 that alternately drives these. The pump unit 100 connected to the pump unit 100
The damper 200 for reducing the pulsation of the slurry liquid discharged by the pump is formed in the same column shape as the pump bodies 1 and 2. These pump unit 100 and damper 20
0 is arranged in-line on the tank 4 containing the slurry liquid 5.

Each pump body 1 of the pump unit 100
2 are connected to the pipes 403 and 404 via the check valve 17 respectively. These pipes 403, 4
Reference numeral 04 is commonly connected to an upper end of one pipe 401 whose lower end is connected to the tank 300 by a pipe joint 402.
The upper outlets of the pump bodies 1 and 2 of the pump unit 100 are connected to the pipes 405 and 40 via the check valve 18, respectively.
6 is connected. These pipes 405 and 406 are commonly connected to one pipe 408 via a pipe joint 407. The pipe 40 arranged in-line with the pipe 408
9, a damper 200 is interposed.

FIGS. 2A and 2B show the pump unit 10.
FIG. 2A is a plan view and FIG. The two columnar pump bodies 1 and 2 are tubular diaphragm pumps forming a quadrangular prism. Actuator 3 for driving these
Are formed in the same quadrangular prism shape as the pump bodies 1 and 2. The pump bodies 1, 2 and the actuator 3 are aligned and attached to the support frame 6 such that the side faces of the pump bodies 1, 2 are in contact with the adjacent side faces of the actuator 3,
A pump unit 100 is configured.

The pump bodies 1 and 2 have the same structure.
The structure of the pump main body 1 will be described with reference to the cross section of FIG. 2B. In the quadrangular cylindrical body 11, a cylindrical space 12 whose inner diameter is narrowed at both ends is formed inside. This cylinder 11
A flexible tube 13 that partitions the columnar space 12 is stretched so as to straddle both ends of the tube 13. The inside of the tube 13 is a liquid passage or pump chamber 14, and the outside is a working fluid space 15.
, A tube-type diaphragm pump is configured.

The flexible tube 13 can be made of rubber or various resins. In the case of this embodiment, the flexible tube 13 contains a CM containing a slurry liquid.
Fluororesin is used because it is applied to transfer the P solution. Check valves 17 and 18 are attached to both ends of the cylindrical body 11 so as to be connected to both ends of the tube 13, respectively, and a suction port 19 and a discharge port 20 for a liquid to be transferred are provided. A flange is formed at both ends of the tube 13 and is connected to the end of the cylindrical body 11 and the check valves 17 and 1 as shown in the figure.
The check valves 17 and 18 are attached so as to be sandwiched between the seats 8. Thus, the pump chamber 14 and the working fluid space 15 are sealed using the tube 13 as a sealing material. Since the tube 13 also serves as a sealing material, an O-ring or the like becomes unnecessary. The cylindrical body 11 is provided with a hole 16 for connecting the internal cylindrical space 12 to the outside of the side, and the hole 16 serves as a working fluid passage.

The actuator 3 comprises two upper and lower cylinders 30 for alternately driving the two pump bodies 1 and 2.
a, 30b and the piston heads 3 respectively housed therein
2a and 32b. The upper cylinder chamber 31 a is directly connected to the working fluid space 15 via a hole 36 a, and is directly connected to a hole 16 which is opened at an upper side surface of the pump body 1 with a gap 35 therebetween. Lower cylinder chamber 31b
Similarly, through the hole 36b, it is directly connected to the hole 16 opened on the lower side surface of the other pump body 2. A working fluid is sealed in the cylinder chambers 31a and 31b of the actuator 3 connected to the working fluid spaces 15 of the pump bodies 1 and 2, respectively. These cylinder chambers 31a, 31
Fluorine oil is used for the working fluid sealed in the working fluid space 15 of the pump body 1 and the pump bodies 1 and 2, but water, ethylene glycol or the like may be used.

Between the cylinder chambers 30a and 30b, respective piston heads 32a and 32b are connected to a gas supply end 34.
An air drive unit 35 that is driven by air supply from a and b (specifically, for example, supply of compressed air or compressed nitrogen gas) is provided. Proximity switches 33a and 33b for detecting the proximity of the piston rod are provided in the air driving unit 35.
Is stored. As mentioned above, two cylinders 3
Oa and 30b are arranged with a symmetrical structure with the air drive unit 35 interposed therebetween. The entire actuator 3 including the air drive unit 35 is formed in a quadrangular prism shape similar to the pump bodies 1 and 2.

FIG. 3 shows the structure of the damper 200 shown in FIG. The damper 200 has the same appearance and internal structure as the pump bodies 1 and 2. That is, the damper 200
Is constituted by using a cylindrical body 301 in which a cylindrical space 302 whose inner diameter is narrowed at both ends is formed. A flexible tube 303 is provided so as to partition the cylindrical space 302 of the cylindrical body 301.
Is stretched between both ends of the cylindrical body 301. The inside of the tube 303 becomes the liquid passage 304, and the outside becomes the working fluid space 305. The working fluid space 305 is connected to the outside via a hole 306 formed in the side surface of the cylinder 301. Compressed gas (air or nitrogen) is supplied as a working fluid through the hole 306, whereby the tube 30
3 is variably controlled.

When performing automatic control of the damper 200,
The pressure sensor 307 detects the supplied hydraulic pressure. The output of the pressure sensor 307 is sent to the controller. As a result, the electropneumatic regulator is controlled by the controller, and the air supply to the working fluid space 305 is automatically controlled. The slurry with a constant flow rate sucked up by the pump unit 100 and suppressed in pulsation by the damper 200 is sent to the CMP processing unit of the semiconductor manufacturing apparatus.

As described above, in this embodiment, the pump bodies 1 and 2 and the damper 200 have the same tubular diaphragm structure. Therefore, the slurry liquid does not stay or settle inside the pump bodies 1 and 2 and the damper 200. Further, the pump unit 100 and the damper 200 are connected in-line to the upper part of the tank 4 using a straight pipe, and the slurry liquid is transferred at a constant flow rate without pulsation. Therefore, the slurry liquid does not accumulate in the middle of the transfer path of the pump system or the particles do not settle, so that a long-life slurry liquid transfer system can be obtained.

FIGS. 4A and 4B are a side view and a rear view of a pump unit 100a according to another embodiment of the present invention. In the previous embodiment, the actuator 3 is arranged vertically in alignment with the two pump bodies 1 and 2, whereas in this embodiment, the actuator 3a is connected to the pump bodies 1 and 2.
And is arranged in a horizontally long state. While the actuator 3 of the previous embodiment uses a piston, the actuator 3a of this embodiment uses a bellows 503a, 503 with movable ends 506a, 506 instead of the piston.
b is used. The two cylinders 30a, 30b accommodating the bellows 503a, 503b are arranged with a symmetrical structure with the air drive unit 35 interposed therebetween.

Ring-shaped pedestals 504a and 504b are hermetically attached to the base ends of the cylinders 30a and 30b by O-rings. The ends of the bellows 503a and 503b opposite to the movable ends 506a and 506b
04a, 504b. Accordingly, the cylinder chambers 31a and 31b in which the working fluid is sealed, and the air spaces 505a and 505 of the bellows 503a and 503b.
The space between b is sealed. With such a structure, the movable end 5
The leakage of the fluorine oil sealed in the cylinder chambers 31a and 31b is prevented without causing the cylinders 06a and 505b to slide on the inner walls of the cylinders 30a and 30b.

The two cylinder chambers 3 of the actuator 3a
The openings 36a, 36b of 1a, 31b are arranged upward. The openings 36a, 36b and the pump bodies 1, 2 are connected by transparent resin pipes 501a, 501b, as shown in FIGS. Fluorine oil, which is a working fluid, is also sealed inside the resin pipes 501a and 501b. In order to monitor the transparency inside the transparent resin pipes 501a and 501b,
As shown in FIG. 4A, a photo sensor 502 is provided.

If the flexible tubes 13 of the pump bodies 1 and 2 are damaged, the transferred slurry liquid leaks into the working fluid space 15. The slurry liquid that has leaked into the working fluid space 15 diffuses toward the actuator 3a via the resin pipe 501a or 501b. Photo sensor 5
By monitoring the turbidity inside the pipes 501a and 501b with 02, it is possible to detect leakage of the slurry liquid.

As described above, according to this embodiment in which the actuator 3a is disposed separately from the pump bodies 1 and 2,
The breakage of the flexible tube 13 of the pump bodies 1 and 2 can be easily detected.

FIG. 6 shows the overall configuration of the slurry liquid transfer system including the parts for performing air supply and control. This system uses the pump unit 1 shown in FIGS. 4 (a) and 4 (b).
12 shows a configuration in the case where 00a is used. As shown, an air control unit 601 for supplying compressed air to the actuator 3a and the damper 200 of the pump unit 100a, and a controller 602 for controlling the air control unit 601 are provided.

The compressed air is supplied to a manual regulator 610,
Automatic electro-pneumatic regulator 611 and switching valve 612
Are supplied alternately to the respective air supply ends of the actuator 3a. Compressed air is also supplied to damper 200 via another manual regulator 613. The controller 602 performs variable control of the electropneumatic regulator 611,
Two proximity switches 33a and 33b of the actuator 3
The switching control of the switching valve 612 according to the output of is performed. Thus, in the two pump bodies 1 and 2, the working fluid space alternately increases and decreases the pressure, and alternately discharges the liquid.

In this system, the controller 6
By setting the discharge amount at 02, automatic control for keeping the pump discharge amount constant regardless of load fluctuation is also possible. Load fluctuation is
It appears as a change in the pump operating frequency by the actuator 3a. Therefore, the outputs of the two proximity switches of the actuator 3a are taken into the controller 602 and monitored,
Electro-pneumatic regulator 6 so that its output frequency is constant
11 automatically controls the supply air pressure to the actuator 3a. As a result, even when there is a load change, control is performed to keep the discharge amount constant.

In order to perform automatic control of the damper 200, an electropneumatic regulator may be provided also in an air supply path to the damper 200. In this case, as described with reference to FIG. 3, the pressure sensor 307 detects the hydraulic pressure supplied to the damper 200 and sends it to the controller 602,
02 controls the electropneumatic regulator.

As described above, according to the present invention, by connecting the tube pump unit and the damper having the same structure in-line, there is no stagnation of slurry liquid and no sedimentation of particles, It is possible to obtain a long-life pump system for transferring a slurry liquid without a local load and without generation of dust and no change in discharge flow rate.

[Brief description of the drawings]

FIG. 1 shows a configuration of a pump system for transferring a slurry liquid according to an embodiment of the present invention.

FIG. 2 shows a plan view of the pump unit according to the embodiment and a sectional view taken along the line AA ′ of the pump unit.

FIG. 3 shows a damper structure of the embodiment.

FIG. 4 shows a configuration of a pump unit according to another embodiment of the present invention.

FIG. 5 shows the structure of the actuator of the embodiment.

FIG. 6 shows a configuration of a pump control system of the embodiment.

FIG. 7 shows a conventional liquid transfer pump.

FIG. 8 shows a damper structure used in a conventional liquid transfer pump.

FIG. 9 shows another example of a conventional liquid transfer pump.

[Explanation of symbols]

100 pump unit, 200 damper, 1, 2 pump body, 3 actuator, 11 cylinder, 12 columnar space, 13 flexible tube frame, 14 pump chamber, 15 working fluid space 16 ... hole (working fluid passage), 17, 18 ... check valve, 19 ... suction port, 20 ...
Discharge port, 30a, 30b ... cylinder, 31a, 31b ...
Cylinder chamber, 32a, 32b ... piston head, 33
a, 33b: proximity switch, 34a, 34b: air supply end, 35: air drive unit, 301: cylindrical body, 302: cylindrical space, 303: flexible tube flam, 304: liquid passage, 305: working gas space , 306 ... holes.

Claims (9)

[Claims] A pair of columnar pump bodies connected in parallel and an actuator for alternately driving them.
A pump unit for sucking and transferring the slurry liquid; and a columnar damper connected in-line to the pump unit to attenuate pulsation of the slurry liquid sucked up by the pump unit. A first cylindrical body having a cylindrical space formed therein, one end of which is a suction port, and the other end of which is a discharge port;
A first flexible tube which is coaxially arranged in the cylindrical space of the first cylindrical body, and has a pump chamber through which the slurry liquid passes, and a working fluid space in which a working fluid is sealed outside; A check valve attached to both ends of the first tubular body and connected to both ends of the first flexible tube, wherein the columnar damper has a columnar space formed therein; A second cylinder having one end connected to the pump unit and a discharge port connected to the other end of the pipe, and a second cylinder coaxially disposed in the cylindrical space of the second cylinder. A second flexible tube having an inner side as a passage through which the slurry liquid to be transferred passes and an outer side as a working fluid space, and a tube pump system for transferring a slurry liquid. 2. The actuator according to claim 1, wherein the actuator includes a pair of cylinders each having an opening connected to a working fluid space of each of the columnar pump bodies, a piston or a bellows reciprocally arranged in each cylinder, and the piston or the bellows. 2. The slurry pumping tube pump system according to claim 1, wherein the tube pump system is a double-acting type having a gas drive chamber for driving the bellows with a compressed gas. 3. The slurry liquid according to claim 2, wherein a kind selected from fluorine oil, water, and ethylene glycol is sealed in a working fluid space of each columnar pump body and each cylinder of the actuator. Tube pump system for transfer. 4. The tube pump system for transferring a slurry liquid according to claim 1, wherein a compressed gas is supplied to a working fluid space of the damper. 5. The tube pump system for transferring a slurry liquid according to claim 2, wherein the pair of cylinders of the actuator are arranged symmetrically with respect to the gas drive chamber. 6. The actuator according to claim 1, wherein the pair of cylinders are formed in a column shape vertically arranged with the gas drive chamber interposed therebetween, and the actuator is connected to the pump unit such that a side surface thereof is in contact with a side surface of each of the columnar pump bodies. 3. The tube pump system for transferring a slurry liquid according to claim 2, wherein the tube pump system is arranged. 7. The slurry liquid according to claim 2, wherein the actuator is disposed apart from the pump unit, and the actuator is connected to the pump unit by a transparent resin pipe filled with a working fluid. Tube pump system for transfer. 8. A slurry liquid transfer tube according to claim 7, further comprising a photosensor for monitoring turbidity inside said transparent resin pipe and detecting leakage of the slurry liquid from said pump unit. Pump system. 9. It comprises a pair of columnar pump bodies connected in parallel and an actuator for alternately driving them.
A pump unit for sucking up and transferring the slurry liquid, and a columnar damper connected in-line to the pump unit to attenuate the pulsation of the slurry liquid sucked up by the pump unit. A cylindrical body having a cylindrical space formed therein, one end of which is a suction port connected to the pump unit, and the other end of which is a discharge port connected to a pipe, and a coaxial shape formed in the cylindrical space of the cylindrical body. A flexible tube which is disposed and has an inner side as a passage through which the slurry liquid to be transferred passes, and an outer side as a working fluid space, comprising a flexible tube.