JPS6084137A - Chemical liquid supply monitoring apparatus from hermetically closed goods-delivery can - Google Patents

Abstract

PURPOSE:To make it possible to stably and continuously perform the supply of a chemical liquid, by supplying the chemical liquid in a hermetically closed chemical liquid goods-delivery can through a monitoring tank and performing control so as to use the chemical liquid in the monitoring tank during the time when the emptied goods-delivery can is exchanged. CONSTITUTION:Solenoid valves 61, 63, 64 are opened while a solenoid valve 62 is closed to supply nitrogen pressure to a canistor 10 and a chemical liquid is supplied to a monitoring tank 50. When the liquid level of the monitoring tank 50 reaches a predetermined position, this position is detected by a liquid level meter 80 and the solenoid valve 63 is closed to make nitrogen push-in pressure equlibrium. In this case, the liquid level meter 80 is attached onto the seat plate 501 of a pedestal 500 along with the solenoid valves 61-64 and connected to the monitoring tank 50 by threading a pedestal attaching screw part 400 and the neck part screw part 200 of the monitoring tank 50. The chemical liquid of the canistor 10 is supplied to an apparatus 1 through the monitoring tank 50 by nitrogen pressure and, when the canistor 10 is emptied and the liquid level of the chemical liquid in the monitoring tank 50 is lowered, the lowering in the liquid level is detected by the liquid level meter 8 and an alarm is issued. During the exchange of the canistor 10, the solenoid valves 61, 64 are closed and the solenoid valve 62 is opened to supply the residual liquid of the monitoring tank 50 to the apparatus 1 by nitrogen pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is applicable to semiconductors and other electronic aspects, precision 8! It relates to a monitoring device that monitors the supply of various chemical solutions used in the chemical solution processing process of vessel parts, etc., and in detail, when supplying the chemical solutions to the chemical solution processing process from the sealed returnable cans filled with the various chemical solutions, The present invention relates to a monitoring device that is connected to a returnable can to detect the location of the medicinal solution and supply it stably.

Advances in microfabrication technology for integrated circuits, transistors, etc. are remarkable, and requirements for quality control of the various chemicals used in their manufacture are becoming increasingly strict. In particular, the contamination of microscopic foreign substances that directly affects the product yield is contraindicated, so the stock solution is usually microfiltered and filled into clean containers in a clean environment (inside a clean room) to become the product. Generally, approximately 11 to 81 glass bottles are used as the container. However, since the filling of various chemical solutions into glass bottles is carried out in an open environment, although in a clean room, it is difficult to avoid the possibility of contamination with dust, foreign matter, etc., even if it is not as high as in the outside air. Furthermore, the glass bottle has the drawback of being damaged during the distribution stage, and since the container itself is disposable, there is a problem in how to deal with it. Furthermore, the user has to take the trouble of opening the glass bottle and transferring it to the container of the equipment on the production line that is supposed to be an integrated circuit, and in doing so, there is a possibility that dust or foreign matter may get mixed in with the contents that have been carefully filtered and cleaned. Problems may arise, such as spillage or, in extreme cases, spillage or overflow. For this reason, Kinei's former name is based on a liquid level pressurization method that can be easily used by connecting to the piping of the chemical treatment process without having to open the package to transfer the contents each time it is used, and which eliminates the above disadvantages. Developed a sealed storage container and filed a separate patent application (Patent application 1986-130)
No. 876).

In this case, since the returnable can is newly used for this purpose, it can hold a larger amount than conventional glass bottles, but depending on the material of the returnable can, it is not possible to monitor the liquid volume. Because of the large amount of chemicals, it is difficult to constantly monitor the decrease and replace them.If you do not know that the chemicals are running out and start operating the chemical processing equipment, you may end up with unprocessed defective products. There is a risk of manufacturing.

The present invention solves the above-mentioned drawbacks, supplies the chemical solution while maintaining its clean state without exposing it to the outside air, and issues an alarm when the amount of the chemical solution reaches an appropriate amount,
In addition, even while replacing the empty returnable can, the chemical solution can be continuously supplied without stopping the chemical processing device, and the streamlined arrangement of the device components makes it extremely compact. This provides a drug solution supply monitoring device that is easy to operate.

The device of the present invention is installed between a closed type returnable can that transfers chemical liquid using a liquid level pressurization method and a chemical liquid processing process.
The chemical liquid sent from the returnable can enters the closed type monitoring tank of the present invention, maintains equilibrium with the gas pressure above the liquid level in the monitoring tank, and is sent to the next chemical liquid treatment step.

Next, to explain the function of this device, after the chemical solution in the returnable can is exhausted and becomes empty, when the liquid level in the monitoring tank drops to a predetermined position, it is time to replace the returnable can. At the same time as warning that the returnable can is reached, the pipe between the returnable can and the labial tank and the air supply line for pressurized gas to the returnable can are cut off so that the returnable can can be replaced.
By introducing gas to pressurize the liquid level in the tank to the monitoring tank, it is possible to supply liquid to the chemical treatment process even while the returnable can is being replaced, and the chemical from the replaced returnable can is transferred to the new monitoring tank. By combining it with a gas supply certificate for pressurizing the liquid level in a returnable can, the tank can function as a container for good news and as a Kutsushimain tank when changing cans. It is a thing that makes you possess.

Next, the functions mentioned in "2" will be explained in detail based on the drawings. FIG. 1 is a perspective view of a canister 10, which is a returnable can containing a chemical solution 20, and FIG. 2 is a longitudinal cross-sectional view of the same. , the flange 14 has a male coupler 11 for transporting liquid.
and a male coupler 12 for gas flow, which coupler 11.12 is protected with a cap 30 in the manner shown in FIG. 3 or 4.

FIG. 5 illustrates a conventional technique in which the canister is connected to the semiconductor manufacturing apparatus 1. That is, clean nitrogen is transferred to the female coupler 17. of the nitrogen line. Gas is supplied to the canister 10 from the male coupler 12 for gas distribution, and the chemical liquid 20 is supplied to the canister 10 by the pressure from the female coupler 16 of the liquid line. It is used by supplying it to the device 1 from the liquid transporting male coupler 11.

Originally, if the semiconductor manufacturing equipment had a function that could detect the failure of liquid usage, such as the cumulative flow ff1', it could be used in this state, but the liquid in the returnable can during use could be used. Once the cans are used up, the process of switching to new returnable cans becomes extremely complicated.

FIG. 6 is a schematic explanatory diagram of a chemical liquid supply monitoring device 100 according to the present invention, which includes a monitoring tank 50 that stores a predetermined amount of chemical liquid 20. Liquid level it+' 80 for detecting the liquid level, connecting lower 0. Tank gas exhaust pipe connection port 90. Solenoid valves 64, 62, 63°64 for opening and closing the nitrogen gas and chemical liquid circuits, and the device 10
female couplers 17 and 16 for connecting the canister 10 and the canister 10, which is a returnable container; Nitrogen gas.

Piping that is a circulation circuit for the chemical solution and the solenoid valve 61° 62
, 63, 64, the liquid level tl'80 (7) made'uJ
It is composed of a power supply circuit, operation switches of an operation panel (not shown), and a display power supply circuit.

The principle of use of this device is that the canister 10 is heated by nitrogen pressure.
The liquid inside is sent to the monitoring tank 50 of the device, the liquid level is detected by the liquid level gauge 80, a predetermined liquid level is maintained, and the chemical solution is sent from the monitoring tank 5o to the device 1. As the chemical solution is used, the liquid fik decreases and the canister 10 becomes empty, and when the liquid level in the monitoring tank 50 falls below a predetermined liquid level,
The liquid level gauge 80 detects this and issues an alarm, and the user knows from the alarm that the liquid level in the canister 10 is empty, and removes the canister 10 filled with the chemical liquid. It is exchanged. At the same time, a feature of this apparatus is that even if the canister is replaced while the canister is being replaced, the semiconductor manufacturing apparatus 1 described above can be operated using the remaining liquid in the monitoring tank. The state of use will be explained in detail with reference to FIGS. 6 to 9. In the figure, the arrangement indicated by a thick line indicates that a circuit is formed.

Canister 10 male coupler 12. H and the device 10
0 female couplers '17 and 16 are connected. 0,5~1
, 0 kg/cm" G is supplied to the connection lower 0. The specified electric power is supplied. (Fig. 6) Turn on the start switch (not shown) in the operation panel,
Start the operation. As shown in FIG. 7, the liquid level side 80 senses that the amount of liquid in the monitoring tank 50 is below a predetermined amount, and the solenoid valve 61 opens to pressurize the canister 10. At the same time, the solenoid valve 64 opens to create a circuit for the chemical, and the solenoid valve 63 of the gas exhaust pipe in the tank opens to create a nitrogen escape port, and the chemical is automatically sent to the monitoring tank 50 under nitrogen pressure. Ru. (This state is referred to as filling.) As shown in Fig. 8, when the liquid level in the monitoring tank 50 reaches a predetermined position, the level gauge 80 detects this, and the solenoid valve 63 closes to open the tank gas exhaust pipe. The connection port 90 is closed, the liquid level rises in the monitoring tank 50 until it reaches equilibrium with the nitrogen pushing pressure, and the inflow of liquid stops. As long as the liquid remains in the canister, this state becomes a steady state and the use of the chemical liquid in the semiconductor manufacturing apparatus 1 is started.

(referred to as in use).

With use, the liquid in the canister 10 continues to flow into the monitoring tank 50, and eventually the canister 10 becomes empty and the monitoring tank 5
The liquid level at 0 begins to drop, and when it falls below a predetermined level, the liquid level side 80 is activated to issue an alarm, which is displayed on the operation panel.

(referred to as Kara).

At the same time, as shown in FIG. 9, the solenoid valve 6L64 closes to disconnect the circuit from the gear nister 10, and the solenoid valve 62 opens to apply nitrogen pressure to the monitoring tank 50, making the remaining liquid usable. Since the lower end of the chemical liquid supply pipe is open to the bottom of the monitoring tank, it can be used in this state as long as there is residual liquid.

According to the report, the operator replaces the canister with a filled canister while residual liquid is still present.

Next, when you press the reset button (not shown) on the operation panel, the above-mentioned "filling" state is entered, and the canister 10 is
Liquid transfer from the beginning is started. In this case, the solenoid valve 63 of the monitoring tank 50 opens and the connection port 90 of the gas (nitrogen) exhaust pipe opens, and the pressure in the monitoring tank 50 decreases. Canister
The pressure should be less than the pressure from the monitoring tank 50.
The pressure is positive BH+ with respect to atmospheric pressure, piping resistance, and head difference.
We have made adjustments so that this will continue even in this state,
This enables use in the semiconductor manufacturing apparatus 1 described above.

As mentioned above, by skillfully controlling the pressure in the monitoring tank 50, the present invention not only issues two signals of the fluid level to the vehicle, but also allows continuous use even when the canister 1o is replaced. Take advantage of the benefits of getting used to it.

This invention presents a supply monitoring device for supplying a chemical solution.

Based on the principle of this device, for example, as the liquid level gauge 80,
Capacitive liquid level gauge and float type liquid level gauge.

Alternatively, you can use a phototube type liquid level gauge depending on the purpose. Furthermore, it is also possible to adopt a pneumatic actuation system instead of operating electric power, and the present invention is not restricted in any way no matter which one is adopted.

Furthermore, according to the principle of the present invention, the rising liquid level in the monitoring tank 50 reaches equilibrium due to the pressure in the monitoring tank, and the level gauge outputs a detection signal, so the liquid level that detects a predetermined level is Surface meter 1
Although one unit is sufficient to perform the function, it is also possible to use one or two units to detect both low and high levels.

Various other methods can be considered, but the key point is to use a returnable canister connected to semiconductor manufacturing equipment via a chemical supply monitoring device, and check the presence or absence of chemical liquid and replace the canister. The method of detecting the liquid level does not limit the present invention in any way.

In addition, the material used for the purpose of the present invention must not be one that does not generate foreign substances such as rust due to corrosion, and must not be one that is attacked by a drug and can be eluted or dispersed into the drug and cause contamination. However, the selection must be confirmed by conducting tests in accordance with conventional methods using the target drug to confirm that it can be used. Generally, examples include SUS 304,
SUS 316, tear.

Polypropylene, polyethylene, polyvinyl chloride.

Or S [JS 304, 5LIS, 316 with Teflon lining, fiber-reinforced polypropylene plastic, etc. 1)
It is obvious that the material may be used appropriately depending on the properties of the drug, and the material does not limit the present invention in any way, as described in II.

The mechanism of the apparatus of the present invention has been schematically explained above, but such a chemical supply/output is arranged in communication with the chemical treatment process, and can be installed using a normal piping installation method.
It is extremely difficult to do this in a compact space, and how the control valves should be arranged and how the piping should be connected are important requirements from the perspective of use, such as operation and inspection.

The device of the present invention solves the above problems, does not take up much space, and makes operations and inspections extremely easy. That is, Fig. 10 is a schematic structural diagram of the monitoring tank, Fig. 11 is a detailed diagram of the upper part of the monitoring tank,
As shown in the plan view of the pedestal in FIG.
0 and the mounting screw part 400 of the pedestal are screwed together and can be removed, and the pedestal and the canister are airtightly connected. Solenoid valves 61 and 62 are placed on the seat plate 501 of the pedestal, respectively.
, 63°64 and a liquid level tI80.

Note that a cover 504 is placed over the pedestal to protect the solenoid valve and liquid level gauge. The connection port of the returnable chemical liquid receiving pipe provided with the coupler 16 is connected to the seat plate 501 of the pedestal and the lower partition plate 50.
The conical pedestal side wall 503 between 2 is opened to the outside, and the side wall is fJ
The opening 102 is connected to the solenoid valve 64, exits from the solenoid valve 64, and passes through the lower partition plate to form an opening 102 to the viewing tank 5o. The process chemical liquid supply pipe passes through the partition plate from the opening 103 at the bottom of the monitoring tank 50 and opens as the connection lower 3 through the side wall. The pressurized gas receiving pipe enters the space between the seat plate of the pedestal and the lower partition plate from an appropriate position on the side wall, and the pipe 300 branches into two paths, one entering the solenoid valve 61, exiting from the solenoid valve 61, and passing through the side wall. It opens to the outside and a coupler 17 is attached.

The other side enters the solenoid valve 62, exits the solenoid valve 62, passes through the lower partition plate, and becomes the opening 101 in the monitoring tank 5o, and the gas in the tank flows from the opening 104 to the bottom partition plate. The solenoid valve 63 passes through the side wall 503 and ends at the connection port 9o. In addition, the detection unit 105 of the liquid level gauge
is inserted into the observation tank through the lower partition plate 502.Since this lightning vision device has the structure described above, all the connections of the tubes are made on the side wall of the upper pedestal. Because
It takes up a lot of space and is very convenient to operate. In addition, only one connection to the nitrogen supply source is required, and the supply of nitrogen to the canister and the operation of the valve are performed in the main monitoring tank, making the operation very easy. In addition, since the liquid level control and electromagnetic valves are installed together on the pedestal, inspection and maintenance are convenient, and the circuit that connects to the operation panel (not shown) can be done all together in an orderly manner. This further enhances the effectiveness of using the device.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a sealed returnable can, Figure 2 is a vertical cross-sectional view of the assimilation, Figures 3 and 4 are detailed views of the flange of the returnable can,
FIG. 5 is an explanatory diagram showing a conventional method of connecting returnable cans to manufacturing equipment, FIG. 6 is a system diagram of a device connected to a chemical liquid supply monitoring device according to the present invention, and FIGS. 7 to 9 are These are schematic explanatory diagrams showing the principle of use of the device of the present invention; FIG. 10 is a schematic view of the watchtower structure of the device of the present invention, and FIG. 11 is a detailed front view of the pedestal.
FIG. 12 is a plan view of the same. 1...Semiconductor manufacturing equipment. 5...Cart for transporting returnable cans. 10... Canister-9 11... Male coupler for liquid transport. 12...Male coupler for gas circulation. 13...The main body of the can for storage. 14...Flange. 16...Female coupler of liquid line. 17...Nitrogen line female coupler. 20...Medicine, 30...Cap. 50...Watch! , 61-64...Solenoid valve. 70... Connection port for pressurized gas receiving pipe. 80...Liquid level it. 90...Connection port for the gas exhaust pipe in the tank. 700... Chemical solution supply monitoring device. 200...Watch tank neck screw part. 400...Pedestal removal screw part. 500... pedestal, 501... pressure plate. 502... lower partition plate, 503... pedestal side wall. 504...BJ bar. Patent applicant: Zeon Corporation, Fujitsu Limited, patent attorney: Keiji Matsunaga

Claims (1)

[Scope of Claims] 1. A closed system equipped with a continuous chemical liquid receiving pipe, a process chemical liquid supply pipe, a pressurized gas receiving pipe, a continuous can air supply pipe, a monitoring tank air supply pipe, an in-tank gas exhaust pipe, and a liquid level gauge. type monitoring tank, and when the liquid level in the monitoring tank falls to the predetermined position of the liquid level gauge, the valves of the returnable chemical solution receiving pipe and the returnable tank air supply pipe are opened and closed. Operate the valve on the internal liquid level from closed to open, reverse the opening and closing of each of the above valves, and operate the valve of the gas exhaust pipe in the tank from closed to open, and collect x# from the exchanged canister. and a valve control mechanism that closes the valve of the gas exhaust pipe in the tank when the designed surface rises to a predetermined position of the liquid level gauge, and the valve control mechanism closes the valve of the tank gas exhaust pipe, Attach a cylindrical pedestal, and attach the pipe ends of the chemical liquid receiving pipe, process chemical liquid supply pipe, pressurized gas receiving pipe, one-way transmission trachea, and tank gas haiku pipe to the side wall between the pedestal surface and the tank ceiling surface. Open the canister receiving pipe valve and the commutable double air pipe valve on the pedestal. 1. A monitoring device for supplying chemical liquid from a closed type returnable can, characterized in that a liquid level valve in a monitoring tank, a gas exhaust pipe valve in the tank, and the liquid level head are attached.