JP2001274136A - Apparatus for treating substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for treating a wafer, in which corrosion of waste fluid passage and leakage of ozone gas can be prevented by removing ozone from used solution containing ozone. SOLUTION: Multiple balls 33 of aluminum oxide are contained in an ozone decomposition chamber 31 and a detour 43, such that they do not impede conduction of used solution. Used solution discharged from a treating unit 2 touches the surface of aluminum oxide balls 33 to decompose ozone contained in the used solution efficiently. Consequently, highly reactive ozone scarcely remain in the used solution discharged from a discharge section 36.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a substrate processing apparatus for processing a substrate such as a semiconductor wafer, a glass substrate for a liquid crystal display panel, or a mask substrate for a semiconductor manufacturing apparatus with an ozone-containing solution.

[0002]

2. Description of the Related Art Conventionally, in a cleaning process for cleaning a substrate, for the purpose of growing an oxide film, removing particles, removing metals, removing organic substances, etc., ozone water in which ozone is dissolved in pure water or ozone water in a chemical solution is used. The substrate is treated with an ozone-containing solution such as an ozone solution in which is dissolved. The concentration of the ozone-containing solution used in such a processing step is gradually increasing with the development of an ozone-containing solution manufacturing apparatus.

[0003]

In such a substrate processing apparatus using an ozone-containing solution, the ozone-containing solution used for processing the substrate is discharged as a drain. Since the drainage from the ozone-containing solution has a high reactivity, the piping and packing constituting the drainage route are corroded by the drainage of the ozone-containing solution, and the drainage containing ozone is discharged from the drainage route to the environment. It may have an adverse effect.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to remove ozone from a drain of an ozone-containing solution, thereby preventing corrosion of a drain passage and leakage of ozone gas. It is intended to provide a device.

[0005]

According to a first aspect of the present invention, a processing unit for processing a substrate with an ozone-containing solution, and a drain containing ozone discharged from the processing unit are brought into contact with a metal oxide. And an ozone removal unit that removes ozone by decomposing ozone.

According to a second aspect of the present invention, in the first aspect, aluminum oxide is used as the metal oxide.

According to a third aspect of the present invention, a processing unit for processing a substrate with an ozone-containing solution, and a wastewater containing ozone discharged from the processing unit are brought into contact with a metal to decompose ozone, thereby obtaining ozone. And an ozone removal unit that removes ozone.

According to a fourth aspect of the present invention, in the third aspect of the invention, aluminum is used as the metal.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of a substrate processing apparatus 1 according to a first embodiment of the present invention.

The substrate processing apparatus 1 includes a processing unit 2 for processing a substrate with ozone water as an ozone-containing solution.
And an ozone removal unit 3 for removing ozone from the wastewater containing ozone discharged from the processing unit 2. The processing unit 2 is connected to an ozone water generation unit 7 for producing ozone water.

The processing unit 2 includes an overflow tank (not shown) for storing ozone water supplied from the ozone water generation unit 7. In this processing unit, the ozone water supplied from the ozone water generation unit 2 is jetted from a supply pipe arranged at the bottom of the overflow tank toward the substrate in the overflow tank, and the substrate is subjected to a cleaning process by the ozone water. Is done. Then, the ozone water supplied to the processing of the substrate overflows from the upper end of the overflow tank, and is then sent to the ozone removal unit 3 as drainage.

On the other hand, the ozone removing unit 3 decomposes ozone in the wastewater by efficiently contacting the wastewater containing ozone discharged from the processing unit 2 with aluminum oxide as a catalyst for decomposing ozone. It consists of an ozonolysis unit.

FIG. 2 is a schematic diagram showing the configuration of the ozone removing unit 3. As shown in FIG.

The ozone removing unit 3 has an introduction path 32 for introducing a waste liquid containing ozone discharged from the processing unit 2, and an end of the introduction path 32 is disposed in the ozone decomposition chamber 31. Have been. A bypass 34 formed by a plurality of partition walls 35 is arranged on the side of the ozone decomposition chamber 31. The end of the bypass 34 is a discharge section 36 for discharging the waste liquid after the ozonolysis.

A large number of aluminum oxide spheres 33 are accommodated in the ozone decomposition chamber 31 and the detour 43 so as not to hinder the flow of the waste liquid. The smaller the sphere 33 of aluminum oxide, the larger the surface area and the higher the ozone decomposition efficiency.
Complicates drainage distribution.

The shape does not necessarily have to be a sphere, but may be an irregular shape, and preferably has a large surface area and allows the drainage to flow easily. In this embodiment, aluminum oxide having a sphere diameter of about 2 to 5 mm was used. In FIG. 2, the aluminum oxide sphere 33 is drawn large for convenience of illustration, and the number of the sphere 33 is also small. However, a large amount is contained so as to substantially fill the ozone decomposition chamber 31 and the bypass 34. ing.

Further, it is not always necessary to be granular, and for example, a net-like member formed by knitting a metal aluminum wire rod may be used.

The wastewater containing ozone discharged from the processing unit 2 is sent into the ozone decomposition chamber 31 through the introduction path 32, and comes into contact with the surface of the aluminum oxide sphere 33,
Ozone contained in the wastewater is efficiently decomposed. The wastewater containing ozone is sufficiently stirred while passing through the bypass 34, and the ozone contained in the wastewater is surely decomposed.

When the ozone contained in the waste liquid is decomposed, the ozone contained in the waste liquid is decomposed into oxygen. For this reason, in the drainage discharged from the discharge unit 36,
Almost no highly reactive ozone remains.

As described above, in the substrate processing apparatus 1 according to this embodiment, the ozone removal unit 3 decomposes ozone in the wastewater containing ozone discharged from the processing unit 2 and then decomposes the ozone. With this configuration, it is possible to prevent corrosion of the drainage path and leakage of ozone gas.

Next, another embodiment of the present invention will be described. FIG. 3 is a schematic diagram of a substrate processing apparatus 1 according to the second embodiment of the present invention. In addition, about the member similar to 1st Embodiment mentioned above, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

The substrate processing apparatus 1 according to the second embodiment
In this method, a substrate is treated with a mixed solution of ozone water and hydrofluoric acid as an ozone-containing solution. In the substrate processing apparatus 1, the processing unit 2 is connected to an ozone water generating unit 7 for producing ozone water and a hydrofluoric acid storage tank 9 for storing hydrofluoric acid. The ozone removal unit 3 is connected to an ammonia storage tank 8 for storing ammonia. Further, between the processing unit 2 and the ozone removing unit 3, a pH sensor 10 for measuring the pH (pH) of a waste liquid containing ozone discharged from the processing unit 2 is provided.

In the substrate processing apparatus 1 according to the second embodiment, the substrate is cleaned with an ozone-containing solution composed of a mixed solution of ozone water and hydrofluoric acid. Then, the ozone-containing solution provided for the processing of the substrate is sent to the ozone removing unit 3 as a waste liquid. At this time, the pH of the drainage containing ozone is measured by the pH sensor 10.

The drainage containing ozone sent to the ozone removal unit 3 contacts a large number of aluminum oxide spheres 33 built therein inside the ozone removal unit 3 as in the first embodiment. Then, the aluminum oxide is used as a catalyst for ozone decomposition, and ozone in the waste liquid is efficiently decomposed.

At this time, if the pH value of the waste liquid containing ozone is 5.5 or less, the aluminum oxide sphere 3
The decomposition reaction of ozone due to the effect of (3) does not proceed sufficiently. On the other hand, in the substrate processing apparatus 1 according to the second embodiment, since the substrate is treated with a mixed solution of ozone water and hydrofluoric acid, the pH value of the drainage liquid may be 5.5 or less. is there.

For this reason, in the substrate processing apparatus 1 according to the second embodiment, the pH of
When the measured value of the pH is 5.5 or less, ammonia as an alkaline solution is supplied from the ammonia storage tank 8 to the ozone removing unit 3 so that the wastewater containing ozone and the ammonia are discharged. By adopting a configuration in which the pH value of the mixed solution is 5.5 or more, a configuration for promoting the ozone decomposition reaction is employed.

The ammonia stored in the ammonia storage tank 8 may be a waste ammonia generated from the substrate processing line. Further, an alkaline solution other than ammonia may be used.

If the pH value of the waste liquid composed of a mixed solution of ozone water and hydrofluoric acid is always 5.5 or less, the pH value of the waste liquid is not measured by the pH sensor 10 and ammonia is always used. May be supplied.

Also in the substrate processing apparatus 1 according to the second embodiment, the ozone removal unit 3 decomposes ozone in the wastewater containing ozone discharged from the processing unit 2 and discharges it as wastewater. Because it is a configuration,
Corrosion of the drainage path and leakage of ozone gas can be prevented.

Next, still another embodiment of the present invention will be described. FIG. 4 is a schematic diagram of a substrate processing apparatus 1 according to a third embodiment of the present invention. In addition, about the member similar to 1st and 2nd embodiment mentioned above, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

The substrate processing apparatus 1 according to the third embodiment
Comprises a processing unit 2 for processing a substrate with ozone water as an ozone-containing solution, and an ozone removing unit 4 for removing ozone from a wastewater containing ozone discharged from the processing unit 2. The processing unit 2 comprises a first
As in the case of the embodiment, it is connected to an ozone water generation unit 7 for producing ozone water. On the other hand, the ozone removing unit 4 is connected to a supply source 6 of a nitrogen gas as an inert gas.

The processing unit 2 has a configuration similar to that of the first embodiment. On the other hand, the ozone removing unit 4 includes an ozone degassing unit that degass ozone from wastewater by dissolving nitrogen gas in wastewater containing ozone discharged from the processing unit 2.

FIG. 5 is a schematic diagram showing the structure of the ozone removing unit 4. As shown in FIG.

The ozone removing unit 4 temporarily stores the ozone-containing effluent introduced from the introduction pipe 42 and the introduction path 42 for introducing the ozone-containing effluent discharged from the processing unit 2. A storage tank 41, a bubbling nozzle 43 for bubbling the nitrogen gas supplied from the nitrogen gas supply source 6 into the wastewater containing ozone temporarily stored in the storage tank 41, and a gas from above the storage tank 41. An exhaust port 44 for discharging and a discharge unit 45 for discharging the drained liquid after ozone degassing are provided.

In the inside of the ozone removing unit 4, similarly to the inside of the ozone decomposition chamber 31 and the bypass 43,
A large number of spheres 33 of aluminum oxide are accommodated so as not to hinder the flow of drainage and nitrogen gas bubbles. The smaller the sphere 33 of aluminum oxide, the larger the surface area and the higher the ozone decomposition efficiency. However, if the sphere 33 is too small, the flow of the drainage liquid is difficult.

The shape does not necessarily have to be a sphere, but may be an irregular shape, and preferably has a large surface area and allows the drainage to flow easily. In this embodiment, aluminum oxide having a sphere diameter of about 2 to 5 mm was used. In FIG. 2, the aluminum oxide sphere 33 is drawn large for convenience of illustration, and the number of the sphere 33 is also small. Many are accommodated, almost to meet.

Further, it is not always necessary to be granular, and for example, a net-like member formed by braiding an aluminum wire may be used.

The waste liquid containing ozone discharged from the processing unit 2 is sent into the ozone decomposition chamber 31 through the introduction path 42 and is temporarily stored in the storage tank 41. And
The nitrogen gas supplied from the nitrogen gas supply source 6 is bubbled into the drainage temporarily stored in the storage tank 41 via the bubbling nozzle 43 having a large number of nitrogen discharge holes.

As a result, the nitrogen gas dissolves in the waste liquid temporarily stored in the storage tank 41, and accordingly, ozone is degassed from the waste liquid. At this time, the sphere 33 of aluminum oxide housed in the ozone removal unit 4 is used.
Acts as a catalyst and efficiently decomposes ozone in the effluent, thereby interacting with the buffing of nitrogen gas, whereby ozone in the effluent is efficiently degassed as ozone gas and exhausted. Exhausted through 44. Due to the efficient decomposition of ozone by the sphere 33 of aluminum oxide as a catalyst and the interaction of degassing of ozone with nitrogen gas, highly reactive ozone is hardly contained in the effluent discharged from the discharge part 45. It will not survive.

In this embodiment, nitrogen gas is used as a gas for degassing ozone, but any other gas other than ozone can be used. However, it is preferable to use an inert gas in consideration of safety and the like.

As described above, in the substrate processing apparatus 1 according to the third embodiment, after the ozone in the waste liquid containing the ozone discharged from the processing unit 2 is degassed by the ozone removing unit 4, Is discharged as a liquid, it is possible to prevent corrosion of the liquid drain path and leakage of ozone gas.

In each of the above embodiments, aluminum oxide is used as the metal oxide as the catalyst for decomposing the wastewater containing ozone. However, the present invention is not limited to aluminum oxide. An oxide of a metal other than aluminum may be used as long as it is a metal oxide that acts as a catalyst.

In the above-described embodiment, aluminum oxide is used as a catalyst for decomposing wastewater containing ozone. This is because aluminum oxide is preferable because of its excellent corrosion resistance, but is limited to metal oxide. not,
For example, it may be a metal like an aluminum material of a metal body. Further, the type of metal is not limited to aluminum.

[0044]

According to the first aspect of the present invention, a processing unit for processing a substrate with an ozone-containing solution, and a waste liquid containing ozone is brought into contact with a metal oxide to decompose ozone and remove ozone. Equipped with an ozone removal unit, to efficiently remove ozone from the ozone-containing solution effluent, thereby preventing corrosion of the effluent path and preventing the effluent containing ozone from leaking to the environment. Becomes possible.

According to the second aspect of the present invention, the first aspect is provided.
In the invention described in the above item, since the metal oxide is aluminum oxide which is oxidized and chemically stable, it can withstand long-term use and stably decompose ozone in drainage for a long time. can do.

According to the third aspect of the present invention, there is provided a treatment unit for treating a substrate with an ozone-containing solution, and an ozone removal unit for removing ozone by contacting a waste liquid containing ozone with metal to decompose ozone. , By efficiently removing ozone from the drainage of the ozone-containing solution, it becomes possible to prevent corrosion of the drainage path and prevent leakage of the ozone-containing drainage to the environment. .

According to the invention set forth in claim 4, according to claim 3,
In the substrate processing apparatus according to the above, in order to use a metal having aluminum as a component having excellent workability,
In order to increase the contact area with the drainage, it can be processed into a freely sized shape, a wide contact area between the drainage and aluminum can be secured, and ozone in the drainage can be efficiently decomposed.

[Brief description of the drawings]

FIG. 1 is a substrate processing apparatus 1 according to a first embodiment of the present invention.
FIG.

FIG. 2 is a schematic diagram showing a configuration of an ozone removing unit 3.

FIG. 3 shows a substrate processing apparatus 1 according to a second embodiment of the present invention.
FIG.

FIG. 4 shows a substrate processing apparatus 1 according to a third embodiment of the present invention.
FIG.

FIG. 5 is a schematic diagram showing a configuration of the ozone removing unit 4.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 2 Processing unit 3 Ozone removal unit 4 Ozone removal unit 5 Hydrogen peroxide water storage tank 6 Nitrogen gas supply source 7 Ozone water generation unit 8 Ammonia storage tank 9 Hydrofluoric acid storage tank 10 pH sensor 31 Ozone decomposition chamber 32 Introducing path 33 Aluminum oxide sphere 34 Detour 35 Partition wall 36 Discharge part 41 Storage tank 42 Introducing path 43 Bubbling nozzle 44 Exhaust port 45 Discharge part

Claims (4)

[Claims] 1. A processing unit for processing a substrate with an ozone-containing solution, and a drain containing ozone discharged from the processing unit.
A substrate processing apparatus comprising: an ozone removing unit that removes ozone by contacting with a metal oxide to decompose ozone. 2. The substrate processing apparatus according to claim 1, wherein the metal oxide is aluminum oxide. 3. A processing unit for processing a substrate with an ozone-containing solution, and a drain containing ozone discharged from the processing unit.
A substrate processing apparatus, comprising: an ozone removing unit that removes ozone by contacting with metal to decompose ozone. 4. The substrate processing apparatus according to claim 3, wherein the metal is aluminum.