JP2000098319A - Liquid chemical treating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the internal pressure of a vessel while preventing an erroneous detection of a sensor controlling liq. level in a thermostatic vessel by removing foams generating in the thermostatic vessel in recirculating a liq. chemical. SOLUTION: A liq. chemical flowing through a supplying path 10 to a treatment vessel flows while being divided also through a thermostatic vessel return path 11 connected to the midway of the path 10. An antifoaming spray 13 is connected at an end part of the path 11 and a liq. chemical is discharged into a thermostatic vessel 1 from this spray 13. The spray 13 is set in a portion where the liq. chemical flows in from a recovering piping 4. A spray flow rate from the spray 13 is regulated by an opening degree of a flow regulating valve 12 of the antifoaming spray set at the midway of the path 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chemical processing apparatus having a function of circulating a chemical used for processing such as a liquid crystal manufacturing process between a constant temperature bath and a processing bath.

[0002]

2. Description of the Related Art In the process of manufacturing a liquid crystal, a chemical solution containing a surfactant or the like is used as a processing liquid when a substrate to be processed is washed or a film on the substrate is etched. The treatment capacity is improved by circulating this chemical solution at a constant temperature in a thermostat.

FIG. 2 is a configuration diagram showing an example of a conventional chemical processing apparatus. As shown in FIG. 2, a processing bath 3 is disposed above a thermostatic bath 1 for keeping the temperature of the chemical solution 2 constant. The temperature of the chemical solution 2 in the thermostatic bath 1 is controlled by a heater 9, the temperature-controlled chemical solution 2 is pumped up by a circulation pump 7, and the processing tank 3 is passed through a processing tank supply path 10 which is a circulation path of the chemical solution 2.
To supply. The chemical solution 2 is discharged from the processing spray 6 provided above the processing tank 3 to the processing tank 3, and processes the substrate 5 in the processing tank 3. At this time, the chemical solution 2 accumulated in the processing tank 3 is naturally removed from the processing tank 3 by the container 1 provided on the outer periphery thereof.
6 and is collected from the container 21 to the thermostat 1 via the collection pipe 4 which is a circulation path of the chemical solution. This is repeated during the processing of the substrate 5 to be processed, and the chemical solution 2 is circulated to improve the processing capacity.

[0004]

However, there is a chemical solution containing a surfactant in the chemical solution 2 used, and bubbles are generated when such a chemical solution is circulated at a considerable flow rate. . Also, the higher the temperature of the chemical solution, the larger the amount of foam generated, but the temperature of the solution cannot be lowered in order to maintain the processing ability. When bubbles are generated, the liquid level management sensor 8, which controls the liquid level in the thermostat 1, detects the bubbles and malfunctions, an interlock for safety operates, and the apparatus stops. I will. Also, when the foam spreads in the thermostat, the internal pressure of the tank increases, and the foam leaks from the thermostat 1.

[0005] The present invention provides a chemical solution treatment for removing bubbles generated in a thermostat when a chemical solution is circulated, preventing erroneous detection of a sensor for controlling the liquid level in the thermostat, and reducing the pressure in the chamber. It is intended to provide a device.

[0006]

According to a first aspect of the present invention, a chemical solution circulation path is provided between a constant temperature bath and a processing bath, a chemical solution is circulated by a pump, and a liquid level management sensor is used to circulate the chemical solution in the constant temperature bath. This is a chemical treatment device that manages the height of the liquid surface to prevent liquid overflow. And it is characterized by comprising a spray for eliminating bubbles generated in the constant temperature bath by a shower.

The invention according to a second aspect is characterized in that a path for introducing a chemical solution flowing through the circulation line to the spray and a mechanism for adjusting a shower amount are provided.

The invention according to claim 3 is characterized in that a bubble intrusion prevention plate for preventing bubbles from entering the liquid level management sensor is provided in the constant temperature bath.

In the present invention, when a chemical solution is circulated between a constant temperature bath and a processing bath to perform processing, bubbles generated in the constant temperature bath are removed.
Defoam by shower. For this reason, malfunction of the liquid level management sensor due to bubbles can be prevented.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing an example of the chemical solution treatment device of the present invention. Since this chemical processing apparatus has substantially the same configuration as the conventional chemical processing apparatus of FIG. 2, the same parts are denoted by the same reference numerals. The chemical solution treatment apparatus of the present invention is different from the conventional one in that a thermostatic bath return path 11 for returning the chemical solution from the middle of the processing tank supply path 10 to the thermostatic chamber 1 and a defoaming spray flow rate adjusting spray for adjusting the chemical flow rate in the thermostatic chamber return path. 12, a defoaming spray 13 disposed above the constant temperature bath 1, a sensor protection partition plate 14 for protecting the liquid level management sensor 8 of the constant temperature bath 1 from bubbles, and a transfer roller 15 for transferring the substrate 5 to be processed. .

As described with reference to FIG. 2, the thermostatic bath 1 and the processing bath 3 are connected to the processing bath supply path 10 which is a chemical liquid circulation path and the recovery pipe 4, and the chemical bath 2 in the thermostatic bath 1 is processed. It is transferred to the processing tank 3 by the circulation pump 7 via the pipe of the tank supply path 10. From the processing tank 3 to the container 1
The chemical solution 2 overflowing to 6 is collected into the thermostat 1 through the collection pipe 4. The chemical solution flowing through the processing tank supply path 10 is supplied to a constant temperature bath return path 11 connected in the middle of the processing tank supply path 10.
It also branches and flows. A defoaming spray 13 is connected to the end of the thermostat return path 11, and the chemical solution is discharged from the defoaming spray 13 to the thermostat 1. The defoaming spray 13 is provided at a portion where the chemical solution flows from the collection pipe 4. The spray flow rate from the defoaming spray 13 is determined by the degree of opening and closing of the defoaming spray flow rate adjusting valve 12 installed in the piping of the thermostat return path 11. Also,
The sensor protection partition plate 14 is arranged in the constant temperature bath 1 so as to partition between the defoaming spray 13 and the liquid level management sensor 8,
In addition, it is provided so as to block the space other than the gap between the bottom of the thermostat 1.

The operation of the processing apparatus will be described below. After the substrate 5 covered with the AL (aluminum) film is transported to the processing tank 3 by the transport roller 15, the circulating pump 7 is operated, and the chemical solution 2 is transferred from the constant temperature bath 1 to the processing tank supply path 10.
From the processing spray 6 to the processing tank 3. When the discharge starts from the processing spray 6, the transport roller 15 rotates left and right, and the processing target substrate 5 is swung in the processing tank 3. The chemical solution 2 that overflows the processing tank 3 is stored in the container 16 and returns to the thermostat 1 via the collection pipe 4.

At this time, the liquid chemical is discharged from the defoaming spray 13 in order to eliminate the bubbles generated in the constant temperature bath 1 when the liquid chemical flows in from the collection pipe 4. That is, the processing tank supply path 10
The chemical solution flowing through the chamber is partially branched and returned to the thermostatic bath return path 11.
Then, the flow rate is adjusted by the defoaming spray flow control valve 12 and supplied to the defoaming spray 13 to be discharged. The reason why the defoaming spray flow rate adjusting valve 12 is provided is that there is a possibility that the supply pressure to the processing tank 3 is reduced or an excessive amount of shower is jetted into the constant temperature bath 1 in consideration of the capacity of the circulation pump 7. This is because the amount of shower to the thermostat 1 can be adjusted.

In this way, the bubbles generated during the circulation of the chemical solution when processing the substrate to be processed are defoamed in the shower using the circulating chemical solution itself, so that the bubbles are removed by exhausting or using a vacuum pump or the like. Furthermore, there is no need to maintain and control the amount and concentration of the chemical solution. Therefore, there is no need to provide a complicated control section for managing the chemical solution.

Further, by providing the sensor protection partition plate 14 in the constant temperature bath 1, the chemical solution 2 is supplied to the liquid level management sensor 8.
Except for the gap with the bottom surface of the thermostatic bath 1 that can enter, the intrusion of the chemical solution is blocked. Since the bubbles generated in the chemical liquid are generated near the liquid surface, there is almost no possibility that the bubbles pass through the gap under the sensor protection partition plate 14, and the bubbles do not directly enter the liquid level management sensor 8 side. In this way, even the bubbles that have not been completely erased by the defoaming spray 13 cannot enter the liquid level management sensor 8 side by the sensor protection partition plate 14, and the malfunction of the liquid level management sensor 8 due to the bubbles can be completely prevented. Since the chemical solution 2 can flow in and out of the gap between the sensor protection partition plate 14 and the bottom surface of the thermostat 1, there is no problem in liquid level management.

When the processing for about 3 minutes is completed, the conveyance roller 15 and the circulation of the chemical solution are stopped. Then, transport roller 1
The substrate 5 is rotated, and the substrate 5 to be processed is transported to a next washing tank (not shown). As the chemical solution 2, a mixed solution containing a surfactant based on phosphoric acid is used.
The resist pattern on the L film is etched to form a pattern of the AL film.

The circulating pressure at the time of processing is set to 1.3 kgf / cm ² with the defoaming spray flow control valve 12 fully opened, and the amount of shower required to eliminate the bubbles generated in the thermostatic bath 1 is reduced. Adjust with the spray flow rate adjustment valve 12,
The processing tank circulation pressure was 1 kgf / cm ² . Now, when the resist pattern on the AL film of the substrate 5 to be processed was etched, it was within the specified pressure range of the etching process conditions, so there was no need to change the process.
Current throughput is maintained.

[0018]

As described above, the present invention is provided with a spray for erasing bubbles generated in the constant temperature bath by a shower, so that it is possible to prevent troubles such as erroneous detection of a liquid level management sensor due to bubbles, No bubbles leak from the thermostat. In addition, by performing the shower using the circulating chemical solution, the amount of the chemical solution can be reduced and the concentration can be maintained, and the etching process can be performed without any problem in the process. Further, the provision of the bubble intrusion prevention plate prevents the bubbles from entering the liquid level management sensor 8 side, and the liquid level management sensor 8 by the bubbles.
Can be completely prevented from malfunctioning.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an example of a chemical solution processing apparatus according to the present invention.

FIG. 2 is a configuration diagram illustrating an example of a conventional chemical treatment apparatus.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 constant temperature bath 2 chemical solution 3 processing tank 4 collection pipe 5 substrate to be processed 6 processing spray 7 circulation pump 8 liquid level management sensor 9 heater 10 processing tank supply path 11 constant temperature bath return path 12 defoaming spray flow control valve 13 defoaming spray 14 Sensor protection partition 15 Transport roller 16 Container

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) // B08B 3/08 H01L 21/306 J F term (Reference) 2H088 FA30 2H090 JC19 3B201 AA03 AB14 AB34 AB42 BB04 BB82 BB94 CB15 CC01 CD22 CD42 CD43 5F043 DD13 DD30 EE07 EE12 EE22 EE23 EE24 EE33 EE36 EE40 GG10

Claims (3)

[Claims] 1. A liquid circulation path is provided between a thermostat and a processing bath, a chemical is circulated by a pump, and a liquid level is controlled by a liquid level management sensor to overflow the liquid. A chemical solution treatment device, comprising: a spray for eliminating bubbles generated in the constant temperature bath by a shower. 2. The chemical processing apparatus according to claim 1, further comprising a path for guiding the chemical flowing through the circulation line to the spray, and a mechanism capable of adjusting a shower amount. 3. The chemical liquid treatment apparatus according to claim 1, further comprising a bubble intrusion prevention plate for preventing bubbles from entering the liquid level management sensor in the constant temperature bath.