JP2000223393A - Device for supplying treating liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for supplying a treating liquid of a structure, wherein an air relief in a storage container can be conducted without breaking a treating liquid supply source and easily. SOLUTION: The end of one side of the ends of a supply line L1 is connected with a trap tank 10, and the other end of the line L1 is soaked in a bottle BT, which is a treating liquid supply source. A supply line L2 connected with the tank 10 is provided with a supply valve 22. Moreover, an exhaust line L3 connected with the upper end of the tank 10 is provided with a pump 30. Normally, the valve 22 is opened, and a resist liquid flows in the lines L1 and L2. When the bottle BT becomes empty, since the air enters the tank 10 and the level of the liquid level in the tank is lowered, the valve 22 is closed, and the bottle BT is exchanged for a new bottle BT. After that, by making the pump 30 conduct a suction operation, the resist is sucked from the new bottle BT, and an air relief in the tank 10 is conducted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoresist (hereinafter, simply referred to as a "substrate") for processing a semiconductor substrate, a glass substrate for a liquid crystal display, a glass substrate for a photomask, a substrate for an optical disk, and the like. , Simply "resist"
And a processing liquid supply device for supplying a processing liquid.

[0002]

2. Description of the Related Art As is well known, a series of substrate processes is achieved by sequentially performing a resist coating process, an exposure process, a development process, and a heat treatment associated therewith on the substrate. Among these processes, the resist coating process and the developing process are performed by discharging a resist or a developing solution onto a substrate from a discharge nozzle. Then, a resist or a developing solution is supplied to the discharge nozzle from the processing liquid supply device.

FIG. 5 is a diagram showing a schematic configuration of a conventional processing liquid supply device. This processing liquid supply device is a device that supplies a resist, guides the resist from a bottle BT that is a resist supply source, and supplies the resist to a discharge nozzle. The resist of the bottle BT is guided to the discharge nozzle by the supply lines L1 and L2.

A trap tank 110 for temporarily storing a resist is provided between the supply line L1 and the supply line L2.
Is provided. The resist stored in the trap tank 110 is sent through the supply line L2 by the pump 120, and is supplied to a discharge nozzle (not shown) through the filter 121 and the supply valve 122.

Further, an exhaust line L3 is connected to the upper portion of the trap tank 110, and the exhaust line L3
Is provided with an exhaust valve 130. Normally, when the resist is supplied to the discharge nozzle by the processing liquid supply device of FIG. 5, the exhaust valve 130 is closed and the supply valve 122 is open.

[0006] As the supply of the resist continues,
The resist in the bottle BT is empty. Then, air is introduced from the supply line L1, and the trap tank 1
The liquid level (liquid level) of the resist in 10 decreases. When the liquid level falls below a predetermined line, the liquid level detection sensor 140 detects that, and issues an alarm.
At this time, the operation of replacing the bottle BT and removing the air flowing into the trap tank 110 is performed.

The procedure of the conventional air bleeding operation is as follows. That is, first, the empty bottle BT
To a new bottle BT. Next, the exhaust line L3
The exhaust valve 130 is opened and the supply valve 1 is opened.
22 is closed. Then, the pressurizing pipe PL is connected to the new bottle BT.

When the inside of the bottle BT is pressurized by the pressurizing pipe PL, the resist of the bottle BT is fed to the trap tank 110 via the supply line L1. At this time, since the exhaust valve 130 is opened and the supply valve 122 is closed, the trap tank 110 is closed.
The liquid level inside rises, and the air is sent out from the exhaust line L3 and exhausted to the drain.

When the operator visually confirms that the liquid level in the trap tank 110 has risen to the optimal line, the exhaust valve 130 of the exhaust line L3 is closed, and the pressurizing pipe PL connected to the bottle BT is connected. remove. Thereafter, the supply of the resist to the discharge nozzle is performed again by opening the supply valve 122 of the supply line L2.

[0010]

As described above, the air bleeding operation in the conventional processing liquid supply apparatus is very complicated. The bottle BT is often made of glass or resin, and when the inside of the bottle BT is pressurized by connecting the pressurizing pipe PL,
Could be damaged.

Further, at the time of the air bleeding operation, the timing at which the exhaust valve 130 of the exhaust line L3 is closed depends on the operator's visual observation. Here, the pressurization from the pressurization pipe PL utilizes a pressurization line in a factory, and the pressure may slightly change depending on the operation state of another device. In addition, since the viscosity varies depending on the type of the resist, the trap tank 1 is supplied via the supply line L1.
The flow rate of the resist pumped to 10 is not always constant. Therefore, during the air bleeding operation, the trap tank 1
It has been very difficult to close the exhaust valve 130 so as to stop the liquid level in 10 at an appropriate position.

If the timing of closing the exhaust valve 130 is delayed, the liquid level rises above the optimum line, and the resist flows into the exhaust line L3 and is discarded into the drain. Since resist is very expensive,
Waste of even a small amount leads to an increase in cost.

Conversely, if the timing of closing the exhaust valve 130 is too early, the liquid level does not reach the optimum line, and a large amount of air remains in the upper part of the trap tank 110. Since the resist deteriorates when it comes into contact with air, it is not preferable that a large amount of air stays in the trap tank 110.

A similar problem also occurs in a device for supplying a developer.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a processing liquid supply apparatus capable of easily bleeding a storage container without damaging a processing liquid supply source. I do.

Another object of the present invention is to provide a processing liquid supply apparatus capable of accurately stopping the liquid level of a processing liquid at an optimum line during an air bleeding operation.

[0017]

According to a first aspect of the present invention, there is provided a processing liquid supply apparatus for supplying a processing liquid for processing a substrate, comprising: A storage container provided in the processing liquid supply path for guiding the processing liquid and temporarily storing the processing liquid, (b) a supply valve provided downstream of the storage container in the processing liquid supply path, (c) An air discharge path connected to the upper portion of the storage container and discharging air retained in the storage container, and (d) a suction unit provided in the air discharge path and suctioning the inside of the storage container, I have.

Further, the invention of claim 2 is a processing liquid supply device according to claim 1, wherein (e) a detecting means for detecting a liquid level of the processing liquid stored in the storage container;
(f) when the suction unit suctions the inside of the storage container, a predetermined amount of suction is further performed when the detection unit detects that the processing liquid is stored at a predetermined level or higher in the storage container. And control means for controlling the suction means so as to stop the suction at a later time.

According to a third aspect of the present invention, in the processing liquid supply apparatus according to the first or second aspect of the present invention, the suction means includes a metering pump capable of sucking a predetermined amount. I have.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of a processing liquid supply apparatus according to the present invention. This processing liquid supply device is a device for supplying a resist, and guides the resist from a bottle BT, which is a resist supply source that is exchangeably installed, and supplies the resist to a discharge nozzle (not shown). The resist of the bottle BT is guided to the discharge nozzle by the supply lines L1 and L2.

A trap tank 10 for temporarily storing the resist is provided in the middle of the processing liquid supply path for guiding the resist from the bottle BT, that is, between the supply line L1 and the supply line L2. FIG. 2 is a sectional view showing the trap tank 10. The trap tank 10 is a closed container having three ports. As the three ports, a processing liquid inlet 11, a processing liquid outlet 13, and a vent 12 are provided. Note that the shape of the trap tank 10 is not limited to the illustrated shape, and may be any shape as long as it can store the processing liquid.

A liquid level detecting sensor 40 for detecting the liquid level of the resist stored in the trap tank 10 is provided beside the trap tank 10. In the present embodiment, a non-contact capacitance sensor is used as the liquid level detection sensor 40. The liquid level detection sensor 40 can detect whether or not the liquid level of the resist stored in the trap tank 10 has reached the reference level TH. The liquid level detection sensor 40 is not limited to the capacitance sensor, and may be, for example, a photoelectric sensor in which a light emitting element and a photoelectric conversion element are combined.

Returning to FIG. 1, a supply line L downstream of the trap tank 10 and connected to the processing liquid outlet 13 is provided.
2 includes a pump 20, a filter 21, and a supply valve 2
2 are provided. The pump 20 has a role as a drive source for feeding the resist stored in the trap tank 10 to a discharge nozzle (not shown). Also, the filter 21
Purifies the resist flowing through the supply line L2. The resist stored in the trap tank 10 is sent through the supply line L2 by the pump 20, and is supplied to the discharge nozzle via the filter 21 and the supply valve 22.

A supply line L 1 is connected to the processing liquid inlet 11 on the upstream side of the trap tank 10. The other end of the supply line L1 is immersed in the resist of the bottle BT.

An exhaust line L3 is connected to an air vent 12 provided at the upper end of the trap tank 10 as an air exhaust path for exhausting air retained in the trap tank 10. In the processing liquid supply device according to the present invention,
A pump 30 is provided in the exhaust line L3 as suction means for sucking the inside of the trap tank 10. The pump 30 is a metering pump capable of sucking a predetermined amount,
For example, a cylinder pump having a constant stroke or a screw pump capable of sucking a constant amount by rotating a constant amount can be employed.

Further, the processing liquid supply device according to the present invention is
The control unit 50 includes a computer. The control unit 50 is electrically connected to at least the pump 30, the liquid level detection sensor 40, and the supply valve 22. The control unit 50 controls these operations according to a program input in advance, and the manner will be described later.

Next, the operation of the processing liquid supply device having the above configuration will be described. During normal processing, when the resist is being supplied to the discharge nozzle, the pump 30 is stopped and the supply valve 22 of the supply line L2 is open. The resist stored in the trap tank 10 is sent through the supply line L2 by the pump 20, is purified by the filter 21, and is supplied to the discharge nozzle. Since the trap tank 10 is a closed container, the same amount of resist as that supplied to the discharge nozzle is sucked from the bottle BT via the supply line L1. Therefore, the liquid level of the resist stored in the bottle BT is always maintained at a constant level during normal processing.

When the processing proceeds and the bottle BT is eventually emptied, air is sucked from the supply line L1. Since the sucked air accumulates in the trap tank 10 upward, there is no possibility that the air enters the discharge nozzle from the supply line L2. However, as the amount of air sucked from the supply line L1 increases, the liquid level of the resist stored in the trap tank 10 gradually decreases, and eventually becomes lower than the reference level TH. When the liquid level of the resist becomes lower than the reference level TH, the liquid level detection sensor 40 detects that fact, transmits the same to the control unit 50, and issues an alarm.

When an alarm is issued, an air bleeding operation is performed. At this time, the delivery of a new substrate is interrupted, and the processing of the substrate being processed is continued. Therefore, trap tank 1
It is preferable that the reference level TH at 0 is set at a position where at least a resist enough to continue processing of a substrate in the middle of processing can be secured.

When the resist coating process is completed for the substrate in the middle of the process, and there is no need to supply a new resist to the discharge nozzle, the empty bottle BT is replaced with a new bottle B.
T and supply valve 2 of supply line L2.
2 is closed. Then, the air bleeding operation is performed by operating the pump 30 provided in the exhaust line L3.

When the pump 30 is operated, the air remaining in the trap tank 10 is sucked by the pump 30 and discharged out of the apparatus through the exhaust line L3. At this time, since the supply valve 22 is closed, the resist does not flow backward from the supply line L2, and the resist is sucked from a new bottle BT via the supply line L1. At the same time when the pump 30 is operated, the control unit 50 is made to recognize that the apparatus is in the air bleeding operation state.

As the air remaining in the trap tank 10 is sucked and discharged, the liquid level of the resist in the trap tank 10 gradually rises and eventually reaches the reference level TH. When the liquid level of the resist reaches the reference level TH, the liquid level detection sensor 40 detects that fact and transmits it to the control unit 50. The control unit 50, which recognizes that the apparatus is in the air bleeding operation state, performs a predetermined amount of suction when receiving a signal from the liquid level detection sensor 40 that the liquid level of the resist has reached the reference level TH. The pump 30 is controlled so that the suction is stopped after the further operation. Here, the “constant amount” means that the resist is in the exhaust line L
3, the suction amount is such that the resist liquid level rises to an optimum line where the air staying in the upper part of the trap tank 10 is below the allowable limit from the viewpoint of resist deterioration. In other words, the “constant amount” is determined so that the liquid level of the resist after the suction of the pump 30 becomes the optimum line.

After the pump 30 further sucks a certain amount according to the instruction from the control unit 50, the pump 30 stops the suction operation.
Thereafter, the supply valve 22 is opened again, and the resist stored in the trap tank 10 is sent through the supply line L2 by the pump 20 and supplied to the discharge nozzle to perform a normal process.

In this way, since the air bleeding operation is performed only by the suction operation of the pump 30, it becomes easier than before. Further, the air bleeding operation is performed by the suction operation of the pump 30, and there is no need to pressurize the bottle BT, so there is no possibility that the bottle BT will be damaged.

The control unit 50 controls the liquid level detection sensor 40
When the pump 30 receives a signal indicating that the liquid level of the resist has reached the reference level TH, the pump 30 is controlled so as to stop the suction after further performing a certain amount of suction. If the “constant amount” is appropriately set in advance, the liquid level of the resist in the trap tank 10 after the suction is stopped can be set to the optimum line. In other words, during the air bleeding operation, the liquid level of the resist can be accurately stopped at the optimum line.

Therefore, the resist is prevented from being wastefully discharged from the exhaust line L3. Further, since the air staying in the trap tank 10 is reduced to a minimum,
The resist no longer contacts the air more than necessary,
Deterioration of the resist can be prevented.

Further, since the pump 30 is a fixed-quantity pump capable of sucking a constant amount, there is no possibility that the trap tank 10 and the bottle BT are pressurized by flowing backward in the exhaust line L3.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described example.
For example, the processing liquid supply device of the above embodiment is a device for supplying a resist, but may be a device for supplying a developer instead.

The suction operation of the pump 30 is controlled by the control unit 50.
Although the control is stopped by the control from the above, it may be performed manually. Since the suction pressure of the pump 30 does not change like the pressure of the conventional pressurizing pipe, the rising speed of the liquid level of the resist in the trap tank 10 is almost constant, and even if it is manual, it is relatively high. The liquid level can be easily stopped near the optimum line. However,
As in the above embodiment, when the control unit 50 controls the pump 30, the liquid level of the resist can be stopped more accurately and stably at the optimum line.

Further, in the above-described embodiment, the apparatus of the system in which one bottle BT is sequentially replaced is used. However, the apparatus of the system in which two or more bottles are connected and used by appropriately switching between them is used. It is good. FIG. 3 is a schematic configuration diagram showing a processing liquid supply device to which two or more bottles are connected.

As shown in FIG. 3, the processing liquid supply device includes two trap tanks 10a and 10b. The supply line L1a is connected to the trap tank 10a, and the other end of the supply line L1a is immersed in the bottle BT1. An exhaust line L3a, which is an air exhaust path, is connected to the trap tank 10a.
3a is provided with a pump 31 as suction means. Further, a liquid level detecting sensor 41 as a detecting means is provided on a side of the trap tank 10a.

On the other hand, a supply line L1b is connected to the trap tank 10b, and the other end of the supply line L1b is immersed in the bottle BT2. Also, the trap tank 10
An exhaust line L3b as an air exhaust path is connected to b, and a pump 32 as suction means is provided in the exhaust line L3b. Further, a liquid level detection sensor 42 as a detecting means is provided on the side of the trap tank 10b.

The trap tank 10a and the trap tank 10b are connected to a supply line L2 via a three-way valve 60. The supply line L2 is provided with the same pump 20, filter 21, and supply valve 22 as in the above embodiment.

The trap tanks 10a and 10b are the same as the trap tank 10 of the above embodiment. Similarly, the pumps 31 and 32 are the same as the pump 30, and the liquid level detection sensors 41 and 42 are the same as the liquid level detection sensor 40.

That is, in the processing liquid supply device of FIG. 3, the trap tank 10, pump 30,
This means that two components including the liquid level detection sensor 40 are connected via the three-way valve 60. And the pump 31,
32, the liquid level detection sensors 41 and 42, and the three-way valve 60 are electrically connected to the control unit 50 and controlled by the control unit 50.

With this configuration, for example, the bottle B
When T1 becomes empty, the three-way valve 60 can be switched to supply the resist from the trap tank 10b, that is, the bottle BT2, to the discharge nozzle. Therefore, unlike the above embodiment, it is not necessary to interrupt the delivery of a new substrate, and normal substrate processing can be performed continuously.

Then, after switching the three-way valve 60, the empty bottle BT1 is replaced with a new bottle BT1, and the trap tank 10a is evacuated. The air bleeding operation at this time is the same as in the above embodiment. That is, the suction operation of the pump 31 is performed under the control of the control unit 50. However, in the processing liquid supply device of FIG. 3, since the normal supply of the resist from the bottle BT2 is continued, the air bleeding operation can have a sufficient time.

Thereafter, when the bottle BT2 becomes empty, the three-way valve 60 is switched to supply the resist from the trap tank 10a, that is, the bottle BT1, to the discharge nozzle. Hereinafter, by repeating the same procedure, the same effect as the above embodiment can be obtained without interrupting the supply of the resist to the discharge nozzle.

FIG. 4 is also a schematic diagram showing a processing liquid supply device to which two or more bottles are connected. The processing liquid supply device of FIG. 4 is provided with a three-way valve 70 on the supply line L1 of the device of FIG.
This is T2. The three-way valve 70 is electrically connected to and controlled by the control unit 50. Other configurations are the same as those of the processing liquid supply device of FIG. 1, and are denoted by the same reference numerals.

In the processing liquid supply apparatus shown in FIG.
When the bottle BT1 becomes empty, the three-way valve 70 is switched,
The resist is supplied from the bottle BT2 to the discharge nozzle. At this time, the resist is not continuously discharged from the discharge nozzle, but is discharged intermittently at regular intervals. Therefore, if the resist is intermittently supplied from the bottle BT2 in synchronization with the constant interval, the dispensing of a new substrate does not need to be interrupted as in the apparatus of FIG. You can do it.

Then, the trap tank 10 is evacuated using the time during which it is not necessary to supply the resist to the discharge nozzle. Specifically, during a time when there is no need to supply the resist to the discharge nozzle, the supply valve 22 is closed, the three-way valve 70 is switched to the bottle BT1, and the pump 30 is operated. On the other hand, when supplying the resist to the discharge nozzle, the supply valve 22 is opened, the three-way valve 70 is switched to the bottle BT2, and the pump 3
Stop 0.

By repeating this, the air bleeding operation of the trap tank 10 is completed, and when the bottle BT2 is eventually emptied, the operation reverse to the above is repeated.

Also in this case, similar to the processing liquid supply apparatus of FIG. 3, the same effects as in the above embodiment can be obtained without interrupting the supply of the resist to the discharge nozzles.
However, when comparing the processing liquid supply apparatus of FIG. 4 with the apparatus of FIG. 3, the mechanical configuration is simpler, but each valve and pump are frequently operated in synchronization with the timing of supplying the resist to the discharge nozzle. The control unit 50
The processing program must be complicated.

It is needless to say that the apparatus shown in FIGS. 3 and 4 may be a processing liquid supply apparatus to which three or more bottles are connected.

[0056]

As described above, according to the first aspect of the present invention, since the suction means is provided in the air discharge path from the storage container, the processing liquid supply source is added when the storage container is evacuated. There is no need to pressurize, and the storage container can be easily vented without damaging the processing liquid supply source.

According to the second aspect of the present invention, when the suction means suctions the inside of the storage container, when the detection means detects that the processing liquid is stored at a predetermined level or more in the storage container, the predetermined amount is set. Since the suction means is controlled so as to stop the suction after the suction is further performed, the liquid level of the processing liquid can be accurately stopped at the optimum line by the constant amount of suction.

According to the third aspect of the present invention, since the suction means includes the metering pump capable of sucking a predetermined amount, the effects of the first and second aspects of the present invention are easily achieved. Can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a processing liquid supply device according to the present invention.

FIG. 2 is a sectional view showing a trap tank of the processing liquid supply device of FIG.

FIG. 3 is a diagram showing a schematic configuration of another example of the processing liquid supply device according to the present invention.

FIG. 4 is a diagram showing a schematic configuration of another example of the processing liquid supply device according to the present invention.

FIG. 5 is a diagram showing a schematic configuration of a conventional processing liquid supply device.

[Explanation of symbols]

 10, 10a, 10b Trap tank 22 Supply valve 30 Pump 40, 41, 42 Liquid level detection sensor 50 Control unit BT, BT1, BT2 Bottle L1, L1a, L1b, L2 Supply line L3, L3a, L3b Exhaust line

Continued on front page F term (reference) 2H025 AB16 AB17 EA00 2H096 AA25 AA27 LA00 4F042 AA06 BA09 CA01 CA07 CB02 CB19 4G068 AA02 AB15 AC05 AD04 AD21 AD36 AE06 AF15 AF25 AF36 AF37 5F046 JA01 JA08

Claims (3)

[Claims] 1. A processing liquid supply apparatus for supplying a processing liquid for processing a substrate, comprising: (a) a processing liquid supply path for guiding the processing liquid from a processing liquid supply source, wherein the processing liquid is temporarily A storage container for storing, (b) a supply valve provided downstream of the storage container in the processing liquid supply path, and (c) an air connected to an upper portion of the storage container and remaining in the storage container. A processing liquid supply device, comprising: an air discharge path for discharging; and (d) suction means provided in the air discharge path, for suctioning the inside of the storage container. 2. The processing liquid supply device according to claim 1, wherein: (e) a detection unit for detecting a liquid level of the processing liquid stored in the storage container; and (f) the suction unit is provided in the storage container. When suctioning, when the detection means detects that the processing liquid is stored at a predetermined level or more of the storage container, the suction means so as to stop the suction after further performing a certain amount of suction. And a control means for controlling the processing liquid. 3. The processing liquid supply apparatus according to claim 1, wherein said suction means includes a metering pump capable of sucking a predetermined amount.