JP2000173972A - Wafer processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently operate a wafer processing apparatus which ejects using an aspirator a processing solution stored in a processing bath, by changing processing solutions inside the processing bath swiftly. SOLUTION: A processing solution is stored in a processing bath 12, and wafers are processed by dipping the wafers in this processing solution. To the processing bath 12, a solution ejecting passage for a processing solution composed of discharging pipes 20, 22, a joining and discharging pipe 24 etc., is connected. By connecting this to the inlet 58 of an aspirator 46, the processing solution is sucked and ejected. Besides, it is possible to transfer the whole processing solution inside the processing bath 12 to the inside of a buffer tank 40 once by pump operation, by providing a pump 26 and the buffer tank 40 in the ejecting passage for this processing solution.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an FPD (Flat Panel) for a semiconductor substrate, a substrate for a liquid crystal display or a plasma display.
The present invention relates to a substrate processing apparatus that performs processing by immersing a substrate such as a substrate for display and a glass substrate for a photomask in a predetermined processing solution.

[0002]

2. Description of the Related Art Conventionally, for example, a substrate such as a semiconductor substrate is immersed in a processing liquid stored in a processing tank, and in this state, the processing liquid in the processing tank is circulated through a circulation path connected to the processing tank. An apparatus for processing a substrate while overflowing a processing solution from a processing bath is generally known.

In this type of apparatus, when the processing capacity of the processing liquid falls below a certain level, the processing liquid in the processing tank is replaced with a new processing liquid. For example, an aspirator for sucking a fluid by a water flow is connected to a drain pipe. And discharging the processing liquid together with the water supplied to the aspirator while sucking the processing liquid in the processing tank with the negative pressure.

According to the apparatus for discharging a processing liquid using an aspirator as described above, the processing liquid can be discharged while being sucked by the aspirator, and the processing liquid is cooled and diluted by water supplied to the aspirator. Since it can be discharged, it is particularly effective when, for example, a processing liquid such as a high temperature, a strong acid or the like is used as the processing liquid.

[0005]

However, such an apparatus for discharging the processing liquid using an aspirator is, for example, compared with an apparatus for discharging the processing liquid using an electrically driven pump or the like. The amount of liquid sent is small, so that the processing liquid in the processing tank cannot be quickly discharged.

Therefore, it takes time to replace the processing liquid in the processing tank, which is a negative factor in operating the apparatus efficiently.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and in a substrate processing apparatus for discharging a processing liquid stored in a processing tank using an aspirator, the processing liquid in the processing tank can be quickly replaced. It is an object of the present invention to provide a substrate processing apparatus capable of efficiently operating the apparatus.

[0008]

In order to solve the above problems, the present invention provides a processing tank for storing a processing liquid and immersing a substrate, a processing liquid drain passage connected to the processing tank, In a substrate processing apparatus provided with an aspirator interposed in the drain passage and sucking a processing liquid, a tank capable of storing a processing liquid discharged through a drain passage is provided between a processing tank and an aspirator; And a liquid feeding means for feeding the processing liquid from the processing tank to the tank through the drainage passage.

In this apparatus, the processing liquid in the processing tank is once transferred from the processing tank to the tank by the liquid sending means, and then the supply of a new processing liquid to the processing tank can be immediately executed. The stored processed liquid can be discharged from this tank while being suctioned by an aspirator. Therefore, it is possible to quickly replace the processing liquid in the processing tank while diluting and cooling the processing liquid and discharging it to the outside of the apparatus as in the conventional apparatus.

In particular, if a pump having a higher liquid sending capacity than the aspirator is used as the liquid sending means (claim 2), the processing liquid in the processing tank can be quickly discharged. In this case, if the storage capacity of the processing liquid in the tank is set to be at least the amount of the processing liquid stored in the processing tank (claim 3), all the processing liquid in the processing tank can be stored in the tank. Therefore, the inside of the processing tank can be quickly emptied.

Further, if the tank is provided with a cooling means for cooling the stored processing liquid (claim 4),
The processing liquid can be cooled by utilizing the period until suction and discharge by the aspirator, which is more effective when discharging a high-temperature processing liquid or the like.

Further, while branching from the drain passage,
A branch passage connected to a second receiving portion different from the first receiving portion from which the processing liquid is discharged by the aspirator, and a state in which the processing liquid discharged from the processing tank is guided to the aspirator and a state in which the processing liquid is guided to the branch passage. If the passage switching means for switching the processing liquid is provided (claim 5), the recovery liquid is recovered in the first receiving portion while diluting and cooling the processing liquid through the aspirator, and the processing liquid is left unmodified (uncooled and undiluted). The method of collecting the processing liquid in the second receiving section can be performed alternatively. Therefore, the degree of freedom in the recovery form of the processing liquid is increased.

[0013]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 schematically shows an embodiment of the substrate processing apparatus according to the present invention. A substrate processing apparatus 10 shown in FIG. 1 stores a processing solution S such as various chemical solutions or pure water in a processing tank, and immerses a plurality of substrates W such as semiconductor substrates in the processing solution S to perform a surface processing. The apparatus includes a processing bath 12 as a substrate processing unit and a processing liquid supply / discharge system for the processing bath.

The processing tank 12 is formed in a box shape having a rectangular cross section, and around the opening thereof, a liquid receiving portion 12a for receiving the processing liquid S overflowing from the processing tank 12.
Are integrally provided, for example, the whole is made of a material having excellent chemical resistance such as quartz.

On the other hand, the processing liquid supply / discharge system is configured as follows. That is, the liquid receiving section 1 of the processing tank 12
2a, a processing liquid supply pipe 16 having an opening / closing valve 18
The upstream end of the supply pipe 16 is connected to the preparation tank 14.
The processing liquid is prepared in the preparation tank 14 and supplied to the liquid receiving portion 12 a through the supply pipe 16.

[0016] Outflow pipes 20 and 22 of processing liquid having opening and closing valves 21 and 23 are connected to the inner bottom of the processing tank 12 and the liquid receiving part 12a, respectively.
22 is connected to the merging outflow pipe 24. An electric drive type pump 26 is interposed in the merging outflow pipe 24, and the discharge side of the pump 26 is connected to a return pipe 28.
And a drain pipe 30, and the return pipe 28 is connected to the processing tank 1.
A drain pipe 30 is connected to a submerged pipe 29 provided at the inner bottom of the pipe 2.
Are connected to the buffer tank 40, respectively.
The return pipe 28 is provided with an open / close valve 32, a heater 34, and a filter 36, while the drainage pipe 30 is provided with an open / close valve 38. The submerged pipe 29
1 extends in a direction perpendicular to the plane of FIG. 1 and has a large number of liquid discharge ports in this direction. During a processing operation described later, the processing liquid is discharged into the processing tank through the liquid discharge ports. It is supposed to be.

The buffer tank 40 comprises a tank having at least the capacity of the processing tank 12. One end of a connecting pipe 42 having an open / close valve 44 is connected to the inner bottom thereof. Is connected to an aspirator 46 for sucking the processing liquid by a water flow. Specifically, the suction port 58 of the aspirator 46
It is connected to the. The aspirator 46 has a water inlet 48 connected to a pressurized water supply source via a water introduction pipe 52 having an opening / closing valve 54, and a water outlet 50 connected to the drain pipe 5.
6 is connected to a waste liquid tank and the like (not shown).

In order to process a substrate by the above-described substrate processing apparatus, first, as a preparation, the opening and closing valve 18 is opened, and the processing liquid prepared in the preparation tank 14 is supplied to the processing tank 12 through the supply pipe 16. To the unit 12a. At this time, the pump 26 is driven with the open / close valves 21 and 32 of the outflow pipe 20 and the return pipe 28 opened and the other open / close valves 38 and the like closed. In this case, the liquid receiver 1
2a is supplied to the outlet pipe 20 and the merging outlet pipe 2
4. Processing tank 12 via return pipe 28 and submerged pipe 29
Is introduced into and stored in
overflows to a. As a result, the processing liquid is stored in the processing tank 12, and is further circulated in the above-mentioned path.

A plurality of substrates W are immersed in the processing liquid S in the processing bath 12 in a state where the processing liquid is circulated in the overflowing manner to process the plurality of substrates W. That is, processing products, particles, and the like generated during the processing are overflowed from the processing tank 12 together with the processing liquid S, and the processing liquid S is purified by trapping the processing products and the like by the filter 36 during the circulation. ing. Although not shown in detail, each substrate W is immersed in the processing liquid S integrally with the substrate support member 11 in a state where the substrates W are supported by the substrate support member 11 in parallel with each other in a direction perpendicular to the plane of the drawing. .

In this way, a plurality of substrates W are immersed,
When the processing capacity of the processing liquid S is reduced to a predetermined level or less, all the processing liquid S stored in the processing tank 12 is replaced with a new processing liquid.

More specifically, first, while the pump 26 is being driven, the open / close valves 18 and 32 of the supply pipe 16 and the return pipe 28 are closed, and all other open / close valves are opened. Thereby, the processing liquid S in the processing tank 12 is introduced into the buffer tank 40 via the outflow pipes 20 and 22, the merged outflow pipe 24 and the drain pipe 30, and the water introduction pipe 5
Water flows from 2 through the aspirator 46 to the drain pipe 56, and the processing liquid introduced into the buffer tank 40 is sucked into the aspirator 46 through the connecting pipe 42. The processing liquid flowing into the aspirator 46 is supplied to the water introduction pipe 5
2 flows into the drain pipe 56 together with the water flowing to the drain pipe 56 through the aspirator 46, and is then discharged to a waste liquid tank or the like.

When all of the processing liquid in the processing tank 12 is exhausted, at that time, the opening / closing valves 23 and 38 of the outflow pipe 22 and the drain pipe 30 are closed, and the supply pipe 16 and the return pipe 28 are opened and closed. The valves 18 and 21 are opened, and the new processing liquid prepared in the preparation tank 14 as described above is supplied to the liquid receiving section 12a through the supply pipe 16. Thus, the processing tank 12
The processing liquid S in the inside is replaced. Further, regardless of the supply of the new processing liquid to the processing tank 12, when the processing liquid in the buffer tank 40 is exhausted, the open / close valves 44, 54 of the connecting pipe 42 and the water introducing pipe 52 are closed.

In the substrate processing apparatus described above, the processing tank 12 and the aspirator 46 are connected to the drainage passage constituted by the outflow pipes 20 and 22, the merged outflow pipe 24, the drainage pipe 30 and the connecting pipe 42 as described above. Between the buffer tank 40
When the processing liquid is exchanged, all of the processing liquid in the processing tank 12 is once drained to the buffer tank 40 at a high speed by pump driving, and subsequently, a new processing liquid is supplied to the processing tank 12. Can be done immediately. The processing liquid introduced into the buffer tank 40 is discharged by the next processing liquid exchange while being sucked by the aspirator 46. For this reason, the processing liquid in the processing tank 12 can be quickly discharged as compared with a conventional apparatus of this type in which the processing liquid is suctioned and discharged directly from the processing tank by an aspirator. Therefore, the processing liquid in the processing tank 12 can be promptly replaced while the processing liquid is diluted and discharged while being cooled as in the prior art, thereby enabling the apparatus to operate efficiently.

In particular, since the buffer tank 40 is constituted by a tank having at least the capacity of the processing tank 12, it is necessary to continuously introduce all the processing liquid in the processing tank 12 into the buffer tank 40. Is possible. Therefore, all of the processing liquid in the processing tank 12 can be discharged very quickly, whereby the time from the start of discharging the processing liquid to the supply of a new processing liquid can be further reduced.

The above-described substrate processing apparatus is one embodiment of the substrate processing apparatus according to the present invention, and its specific configuration can be changed as appropriate without departing from the spirit of the present invention. .

For example, as shown in FIG. 2, a cooling means for cooling the processing liquid stored in the buffer tank 40 may be provided. Specifically, the buffer tank 40
A spiral pipe 60 may be provided, and a water inlet pipe 61 and a water outlet pipe 62 may be connected to both ends of the spiral pipe 60 to circulate cold water through the spiral pipe 60. That is, since the configuration for discharging the processing liquid using the aspirator as described above is often applied to an apparatus using a high-temperature processing liquid, according to the configuration shown in FIG. Since the processing liquid can be cooled using the period in which the processing liquid is stored, the processing liquid can be cooled and discharged more effectively. The structure of the cooling means for cooling the processing liquid stored in the buffer tank 40 is not limited to this. For example, a cooling water circulation passage is integrally formed on the side wall of the buffer tank 40 and the cooling water is cooled in the passage. Water may be passed through. In short, any cooling means may be applied as long as the processing liquid in the buffer tank 40 can be cooled.

Further, a configuration as shown by a two-dot chain line in FIG. 2 may be added. That is, a drain pipe 65 branched from the connecting pipe 42 is provided between the buffer tank 40 and the opening / closing valve 44, and the drain pipe 65 is provided with an opening / closing valve 66, and the drain pipe 65 is connected to the aspirator. It may be connected to a waste liquid tank 67 or the like different from a waste liquid tank or the like connected to the drain pipe 56 of 46. In this way, for a processing liquid having a high risk such as a high temperature and a strong acid, the opening / closing valve 44 is opened and the opening / closing valve 6 is opened.
By closing 6, the processing liquid can be collected while cooling and diluting through the aspirator 46.
For other low-risk processing liquids,
4 is closed and the opening / closing valve 66 is opened, so that the drainage pipe 6 is opened.
5, the processing liquid can be quickly discharged and collected in the same state. That is, according to this configuration, the waste liquid tank or the like connected to the drain pipe 56 is connected to the first receiving portion of the present invention, the drain pipe 65 is connected to the branch passage of the present invention, and the drain pipe 65 is connected to the drain pipe 65 of the present invention. The waste liquid tank 67 and the like are used in the second embodiment of the present invention.
And the opening / closing valves 44, 66 correspond to the passage switching means of the present invention.

In the above-described substrate processing apparatus 10, a part of the passage for circulating the processing liquid to the processing tank 12 is commonly used as a drain passage for the processing liquid. The passage may be provided separately and independently. In this case, the processing liquid may naturally flow into the buffer tank 40 without providing a pump. In addition,
When the pump is not provided, the pipe diameter of the drainage passage is set to be sufficiently large, and the processing liquid S in the processing tank 12 is quickly (that is, higher than the liquid sending capacity of the aspirator) in the buffer tank 40. The drainage system may be configured to be discharged into the inside.

[0029]

As described above, according to the present invention, a substrate is provided in which an aspirator is provided in a processing liquid drain passage connected to a processing tank, and the processing liquid is suctioned and discharged by the aspirator. In the processing apparatus, between the processing tank and the aspirator, a tank capable of storing the processing liquid discharged through the drainage passage and a liquid feeding unit having a liquid sending capacity higher than the liquid sending capacity by the aspirator are provided. The processing liquid in the tank is once transferred from the processing tank to the tank, and then a new processing liquid can be immediately supplied to the processing tank, while the processing liquid once stored in the tank is sucked from this tank by the aspirator. The processing liquid in the processing tank can be discharged more quickly than a conventional device of this type that discharges the processing liquid while sucking it from the processing tank directly using an aspirator. It can be discharged to. Accordingly, the processing liquid in the processing tank can be quickly exchanged while diluting and cooling the processing liquid and discharging the same as in the conventional apparatus, thereby enabling the apparatus to operate efficiently.

In particular, a pump having a higher liquid sending capacity than the aspirator is provided between the tank and the processing tank, and the pump sends the processing liquid in the processing tank to the tank. In this case, the processing liquid in the processing tank can be discharged very quickly. In this case, if the storage capacity of the processing liquid in the tank is set to at least the amount of the processing liquid stored in the processing tank, all of the processing liquid in the processing tank can be stored in the tank, and the processing tank is quickly emptied. Thus, the supply of a new processing liquid can be started at an earlier stage.

Further, if the tank is provided with a cooling means for cooling the stored processing liquid, the processing liquid can be cooled by utilizing the period until suction and discharge by the aspirator. This is particularly effective when discharging a high-temperature processing solution or the like.

Further, while branching off from the drain passage,
A branch passage connected to a second receiving portion different from the first receiving portion from which the processing liquid is discharged by the aspirator, and a state in which the processing liquid discharged from the processing tank is guided to the aspirator and a state in which the processing liquid is guided to the branch passage. If the passage switching means for switching the processing liquid is provided, the degree of freedom of the recovery form of the processing liquid can be increased.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing one embodiment of a substrate processing apparatus according to the present invention.

FIG. 2 is a schematic view showing another embodiment of the substrate processing apparatus according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Substrate processing apparatus 12 Processing tank 12a Liquid receiving part 20,22 Outflow pipe 24 Merging outflow pipe 26 Pump 28 Return pipe 29 Liquid pipe 30 Drain pipe 40 Buffer tank 42 Connecting pipe 46 Aspirator 52 Water introduction pipe 56 Drain pipe S Processing liquid W Substrate

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shuji Nagara 4-chome Tenjin Kitamachi 1-chome, Horikawa-dori-Terauchi, Kamigyo-ku, Kyoto Within Dainippon Screen Mfg. Co., Ltd. (72) Inventor Kenji Amagu, Kyoto 4-chome Tenjin, Horikawa-dori Teranouchi, Ward 1 Kitamachi 1 Dainippon Screen Mfg. Co., Ltd.

Claims (5)

[Claims] 1. A processing tank for storing a processing liquid and immersing a substrate, a drain passage for the processing liquid connected to the processing tank, and an aspirator interposed in the drain passage for sucking the processing liquid. In the substrate processing apparatus provided with, a tank capable of storing the processing liquid discharged through the drain passage between the processing tank and the aspirator, and having a liquid sending capacity higher than the liquid sending capacity by the aspirator. And a liquid feeding means for feeding a processing liquid from the processing tank to the tank through the drain passage. 2. The substrate processing apparatus according to claim 1, wherein the liquid sending means is a pump having a liquid sending capacity higher than a liquid sending capacity by the aspirator. 3. The storage capacity of the processing liquid in the tank is:
3. The substrate processing apparatus according to claim 1, wherein the amount is set to be at least the amount of the processing liquid stored in the processing tank. 4. The tank according to claim 1, further comprising cooling means for cooling the stored processing liquid.
A substrate processing apparatus according to any one of the above. 5. A branch passage branching from the drain passage and connected to a second receiving part different from the first receiving part from which the processing liquid is discharged by the aspirator,
5. The substrate processing apparatus according to claim 1, further comprising a path switching unit configured to switch between a state in which the processing liquid discharged from the processing tank is guided to the aspirator and a state in which the processing liquid is guided to the branch path. .