JP2004031852A - Device for processing substrate and method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for processing a substrate and a method therefor capable of processing by adjusting the ozone concentration of ozone water supplied to the substrate. <P>SOLUTION: The device and the method using it comprises an ozone water generating means 11 that generates the ozone water, a substrate treating means 12 that the substrate by supplying the ozone water, an ozone water supplying pipe 21 treats that supplies the ozone water from the ozone water generating means 11 to the means 12 for processing the substrate, a gas-liquid separation means 13 that is placed in the ozone water supplying pipe 21 and separates the ozone gas and oxygen gas generated from the ozone water, a ozone water regenerating means 14 that is placed adjacent to the substrate treating means 12 and regenerates the ozone water from the ozone gas and the oxygen gas separated with the means 13 for separating liquid and gas, and a regenerated ozone water supplying pipe 26 that supplies the regenerated ozone water from the ozone water regenerating means 14 to a position nearer to the substrate treating means 12 of the pipe 21. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate processing apparatus and a substrate processing method, and more particularly to a substrate processing apparatus and a substrate for processing a semiconductor substrate, a glass substrate of a liquid crystal display device, a glass substrate for a photomask, a substrate for an optical disk, etc. with ozone water. Regarding the processing method.
[0002]
[Prior art]
2. Description of the Related Art In a semiconductor device manufacturing process, with the miniaturization and high integration of semiconductor devices, particles (fine particles), metal contamination, organic contamination, and the like adhering to a semiconductor substrate have a great effect on device yield and characteristics. It is becoming. Therefore, in order to improve the device yield and its characteristics, it is necessary to keep the front and back surfaces of the semiconductor substrate clean throughout the entire manufacturing process. Therefore, in each of the manufacturing processes, a semiconductor substrate cleaning treatment step is appropriately performed.
[0003]
In the above-described cleaning process, wet processing is mainly used from the viewpoint of increasing the diameter of a semiconductor substrate and reducing costs. In such wet processing of a semiconductor substrate, a chemical solution such as aqueous hydrogen peroxide, sulfuric acid, ammonia water, or hydrochloric acid, a mixed solution thereof, or an aqueous solution thereof is used as a processing liquid.
However, in the above-described treatment method, waste liquid treatment is costly in addition to the cost of the chemical solution itself, which is a factor of increasing running cost.
[0004]
Therefore, in recent years, ozone-dissolved water obtained by dissolving ozone in pure water (hereinafter referred to as ozone water) has been used as a treatment liquid for cleaning semiconductor substrates.
Since ozone is produced from oxygen, the ozone water itself is relatively inexpensive, and the ozone in the ozone water is naturally decomposed, so that there is no waste liquid treatment cost.
In addition, ozone water has an oxidizing power next to hydrofluoric acid and is suitable for cleaning treatment. High concentration ozone water is used for such a cleaning process.
[0005]
[Problems to be solved by the invention]
However, ozone is hardly soluble in water and has a high decomposition rate. Therefore, in the ozone water supply pipe for supplying ozone water from the ozone water generation means to the substrate processing means, ozone gas which cannot be completely dissolved in ozone water is converted from ozone water. There is a problem that the ozone gas is eluted or this ozone gas is decomposed to generate oxygen gas, so that a desired ozone concentration cannot be obtained at the stage of the cleaning process in the substrate processing means.
Further, in the ozone water supply pipe, the ozone gas eluted from the ozone water and the oxygen gas decomposed from the ozone water flow together with the ozone water, so that the ozone water becomes difficult to flow.
[0006]
Further, when the ozone water is supplied from the ozone water generation unit to the plurality of substrate processing units and used, the ozone concentration of the ozone water decreases in each of the substrate processing units, and the semiconductor substrate can be sufficiently cleaned. Did not.
[0007]
Therefore, in order to supply ozone water to the substrate processing means while maintaining the ozone concentration of the ozone water generated by the ozone water generation means, it is necessary to arrange the ozone water generation means near the substrate processing means. In the case where the substrate processing means is provided, a plurality of ozone water generating means are required, which is a problem in terms of cost.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, a substrate processing apparatus according to the present invention includes an ozone water generating unit that generates ozone water, a substrate processing unit that supplies ozone water to process a substrate, and an ozone water generating unit. An ozone water supply pipe for supplying ozone water from the ozone water to the substrate processing means; a gas-liquid separation means provided on the ozone water supply pipe for separating ozone gas and oxygen gas generated from the ozone water from the ozone water; And ozone water regenerating means for regenerating ozone water from the ozone gas and oxygen gas separated by the gas-liquid separating means, and regenerating the ozone water from the ozone water regenerating means to a position closer to the substrate processing means of the ozone water supply pipe. And a recycled ozone water supply pipe for supplying ozone water.
[0009]
According to such a substrate processing apparatus, since the ozone water supply pipe is provided with the gas-liquid separation means for separating the ozone gas and the oxygen gas generated from the ozone water from the ozone water, the ozone gas eluted from the ozone water and the ozone gas Oxygen gas, which is decomposed into oxygen gas, can be separated from the ozone water, so that the ozone water can be prevented from flowing together with the gas, and the ozone water can be maintained in a state where it can easily flow.
[0010]
Further, since the apparatus is provided with the ozone water regenerating means for regenerating ozone water from the ozone gas and oxygen gas separated by the gas-liquid separation means, the ozone water is regenerated using the ozone gas and oxygen gas generated from the ozone water. be able to.
Further, since the regenerating ozone water supply pipe for supplying the regenerated ozone water from the ozone water regenerating means to a position closer to the substrate processing means of the ozone water supply pipe is provided, the ozone water regenerating is performed so that the ozone concentration is not lost. Since the ozone water regenerated by the means can be supplied immediately before the substrate processing means, it is possible to compensate for the decrease in the ozone concentration of the ozone water while flowing through the ozone water supply pipe.
Therefore, it is possible to supply the ozone water generated by the ozone water generation means to the substrate processing means while maintaining the ozone concentration.
[0011]
Further, the substrate processing method of the present invention is a substrate processing method of performing processing of a substrate by supplying ozone water, wherein ozone gas and oxygen gas generated from the ozone water are separated from the ozone water in the middle of the supply path of the ozone water. After that, the ozone water is regenerated from the ozone gas and the oxygen gas, and the regenerated ozone water is added to the ozone water separated on the downstream side of the supply path, so that the concentration of the ozone water supplied to the substrate is adjusted. Is performed.
[0012]
According to such a substrate processing method, ozone gas and oxygen gas generated from ozone water in the supply path of ozone water are separated from ozone water, and the ozone water is regenerated from the separated ozone gas and oxygen gas. Then, by adding the regenerated ozone water to the ozone water separated on the downstream side of the supply path, it is possible to compensate for the decrease in the ozone concentration of the ozone water in the supply path. Therefore, the substrate can be processed while maintaining the ozone concentration of the ozone water.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of a substrate processing apparatus and a substrate processing method of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic configuration diagram illustrating an example of a substrate processing apparatus used in the substrate processing method according to the embodiment.
The substrate processing apparatus shown in this figure is for processing the surface of a semiconductor substrate (substrate), for example, with ozone water. The substrate processing apparatus performs processing of the substrate with ozone water generating means 11 for generating ozone water and supplied ozone water. Means 12.
[0014]
The ozone water generating means 11 is configured to generate ozone gas by, for example, silently discharging oxygen to generate ozone gas, bubbling the ozone gas into pure water, and dissolving the ozone gas in pure water, thereby generating ozone water. .
On the other hand, the substrate processing means 12 is for processing the substrate with ozone water. For example, ozone water is stored in a chemical solution tank and the substrate surface is cleaned by immersing the substrate, or while the substrate is rotated. The cleaning process is performed by supplying ozone water to the substrate surface.
[0015]
The ozone water generation unit 11 and the substrate processing unit 12 are connected by an ozone water supply pipe 21, and are configured so that ozone water is supplied from the ozone water generation unit 11 to the substrate processing unit 12. .
A plurality of gas-liquid separation means 13 for separating ozone gas and oxygen gas generated from the ozone water from the ozone water are provided in the ozone water supply pipe 21 along the gas supply pipe 21.
Here, for example, three gas-liquid separation units 13 are provided in the ozone water supply pipe 21 from the ozone water generation unit 11 to the substrate processing unit 12, but the present invention is not limited to this. It is preferable to provide an optimum number according to the decomposition rate of the slag. As an example, it is assumed here that the ozone water supply pipe 21 is provided at intervals of 1 m.
[0016]
Further, a gas supply pipe 22 is connected to the gas-liquid separation means 13, and the other end of the gas supply pipe 22 is connected to the ozone water regeneration means 14. Thus, the ozone gas and the oxygen gas separated by the gas-liquid separation unit 13 are supplied from the gas supply pipe 22 to the ozone water regeneration unit 14.
Further, the gas supply pipe 22 is connected to the ozone water regenerating means 14 from the ozone water generating means 11 so that the ozone gas which has not been completely dissolved in the pure water by the ozone water generating means 11 is also supplied to the ozone water regenerating means 14. It is connected.
The ozone water regenerating means 14 is provided near the substrate processing means 12.
[0017]
Here, the gas-liquid separation unit 13 and the ozone water regeneration unit 14 described above will be described in detail.
As shown in the enlarged view of the main part of FIG. 2, the gas-liquid separation means 13 is a device for separating gas and liquid up and down by weight, and is provided from an ozone water supply pipe 21 connected to the upper part of the gas-liquid separation means 13. Ozone water is supplied, and the ozone water after separation is discharged from an ozone water supply pipe 21 connected to the lower part of the gas-liquid separation means 13.
A gas supply pipe 22 is connected to an upper portion of the gas-liquid separation unit 13 so that the oxygen gas and the ozone gas separated as described above are supplied to the ozone water regeneration unit 14 (see FIG. 1). It is configured.
[0018]
3, the ozone water regenerating means 14 regenerates ozone water from the ozone gas in the ultraviolet ray irradiating section 31 for irradiating ultraviolet rays to generate ozone gas, and the ozone gas in the ultraviolet ray irradiating section 31. And an ozone water regenerating unit 32.
[0019]
The gas supply pipe 22 is connected to the ultraviolet irradiation unit 31, and the ozone gas and the oxygen gas separated by the gas-liquid separator 13 (see FIG. 1), and the ozone water generation unit 11 (see FIG. 1). Ozone gas that has not been completely dissolved in pure water is supplied.
The ultraviolet irradiation unit 31 is provided with, for example, an ultraviolet irradiation unit 33 above the ultraviolet irradiation unit 31. By irradiating the supplied gas with ultraviolet V, ozone gas is generated from oxygen gas.
[0020]
Here, not only oxygen gas but also ozone gas is supplied to the ultraviolet irradiation section 31 of the ozone water regenerating means 14, and the ozone gas may be generated from the oxygen gas therein. Ozone gas can be generated using an inexpensive means.
Here, the wavelength of the ultraviolet ray V is preferably, for example, 172 nm or 182 nm. With this wavelength, ozone gas can be efficiently generated.
A low-pressure mercury lamp and an excimer laser can be used as a light source of the ultraviolet ray V at this wavelength.
[0021]
The ozone water regenerating section 32 disposed adjacent to the ultraviolet irradiation section 31 is provided with, for example, a hollow fiber membrane 34 for dissolving ozone gas in pure water. Then, the ozone gas supplied from around the hollow fiber membrane 34 passes through the hollow fiber membrane 34 to be dissolved in pure water flowing in the hollow portion of the hollow fiber membrane 34.
[0022]
The ozone water regenerating section 32 is connected to a pipe 23 for supplying ozone gas from the ultraviolet irradiation section 31 and an exhaust pipe 24 for exhausting ozone gas that does not pass through the hollow fiber membrane 34.
The exhaust pipe 24 may be connected from the ozone water regeneration unit 32 to the ultraviolet irradiation unit 31, and may be configured such that ozone gas that does not pass through the hollow fiber membrane 34 is supplied to the ultraviolet irradiation unit 31 again. Good.
[0023]
A pipe 25 for supplying pure water to the hollow portion of the hollow fiber membrane 34 is connected to the hollow fiber membrane 34, and ozone water regenerated by dissolving ozone gas is supplied to the ozone water supply pipe 21. A regenerated ozone water supply pipe 26 is connected.
The ozone water thus regenerated from the ozone water regenerating means 14 is supplied to the regenerated ozone water supply pipe 26.
[0024]
Here, the ozone concentration of the ozone water regenerated by the ozone water regenerating means 14 can be adjusted by the amount of pure water supplied from the pipe 25 or the amount of ultraviolet irradiation in the ultraviolet irradiation unit 31. However, as described later, the regenerated ozone water is supplied to compensate for a decrease in the ozone concentration of the ozone water while flowing in the ozone water supply pipe 21. The concentration is adjusted to be higher than that of the ozone water in the ozone water supply pipe 21 immediately before the supply.
[0025]
Then, as shown in FIG. 1 again, the other end of the regenerated ozone water supply pipe 26 is connected to the ozone water supply pipe 21 closer to the substrate processing means 12 than the gas-liquid separation means 13. The configured ozone water is supplied to the ozone water supply pipe 21.
[0026]
Here, it is preferable that the length of the regenerated ozone water supply pipe 26 connecting the ozone water regenerating means 14 and the junction G of the ozone water supply pipe 21 is shorter. With this configuration, a decrease in the ozone concentration of the regenerated ozone water is suppressed.
Further, it is preferable that the distance from the junction G in the ozone water supply pipe 21 to the substrate processing means 12 is also short. With such a configuration, the ozone concentration of the ozone water after the junction G is maintained at a high concentration until it is supplied to the substrate processing unit 12.
By arranging the ozone water regenerating means 14 close to the substrate processing means 12, the length of the regenerated ozone water supply pipe 26 as described above is reduced, and the distance from the junction G to the substrate processing means 12 is reduced. Can be shortened.
[0027]
Next, the substrate processing mechanism 17 for processing the substrate with the supplied ozone water will be described.
The substrate processing mechanism 17 includes a substrate processing unit 12 for processing a substrate, an ozone concentration measuring unit 15 for measuring the concentration of ozone water supplied to the substrate processing unit 12, and a measurement result of the ozone concentration measuring unit 15. And ozone concentration control means 16 for controlling the concentration of ozone water supplied to the substrate processing means 12.
[0028]
The ozone concentration measuring means 15 is provided in the ozone water supply pipe 21 on the substrate processing means 12 side from the junction G, whereby the ozone concentration of the ozone water supplied to the substrate processing means 12 is measured.
Then, the measurement result is fed back to the ozone concentration control means 16, and the ozone concentration control means 16 controls the ozone concentration of the ozone water regenerated by the ozone water regeneration means 14. Then, ozone water whose ozone concentration is controlled is supplied to the junction G from the ozone water regeneration means 14.
[0029]
However, as described with reference to FIG. 3, the ozone concentration of the regenerated ozone water is adjusted so as to be higher than the ozone concentration of the ozone water flowing through the ozone water supply pipe 21 immediately before the junction G. Therefore, the concentration of ozone water after the junction G, that is, the concentration of ozone water supplied to the substrate processing means 12 is adjusted to a higher concentration than before the junction G.
Thus, the concentration of the ozone water supplied to the substrate processing means 12 is controlled by the ozone concentration control means 16.
[0030]
Here, the concentration of the ozone water supplied to the substrate processing means 12 is controlled by controlling the concentration of the ozone water regenerated by the ozone water regenerating means 14. The concentration of the ozone water supplied to the substrate processing means 12 may be controlled by controlling the supply amount of the ozone water supplied to the supply pipe 21.
In this case, for example, a valve provided in the regenerated ozone water supply pipe 26 is configured to be openable and closable by the ozone concentration control means 16, so that the supply amount is controlled.
[0031]
As described above, when adjusting the supply amount of the regenerated ozone water, the ozone water supply pipe 26 is also provided with the ozone concentration measurement means 15, and the measurement result is also fed back to the ozone concentration control means 16. By doing so, it is necessary to control the concentration of the regenerated ozone water supplied from the regenerated ozone water supply pipe 26.
However, when the concentration of the regenerated ozone water is a saturated concentration, the supply can be controlled by the supply amount without providing the ozone concentration measurement means 15 in the regenerated ozone water supply pipe 26.
[0032]
Here, in order to perform the substrate cleaning process, it is preferable to adjust the ozone concentration of the ozone water supplied to the substrate processing means 12 to 30 ppm to 60 ppm. If it is lower than 30 ppm, the substrate cannot be sufficiently cleaned, and if it is higher than 60 ppm, the surface of the substrate may be damaged.
[0033]
When performing a substrate cleaning process using such a substrate processing apparatus, first, a substrate (not shown) is disposed in the substrate processing means 12, as shown in FIG.
On the other hand, ozone water is generated by the ozone water generation means 11 and flows in the ozone water supply pipe 21. While flowing through the ozone water supply pipe 21, the ozone water generates ozone gas and oxygen gas, and is separated into ozone gas, oxygen gas and ozone water generated by the gas-liquid separation means 13.
By repeating the separation by the gas-liquid separation means 13, the flow of the ozone water together with the gas in the ozone water supply pipe 21 can be suppressed.
[0034]
On the other hand, the ozone gas and oxygen gas separated by the gas-liquid separation device 13 and the ozone gas not completely dissolved in the pure water by the ozone water generation device 11 are supplied to the ozone water regeneration device 14, and the ultraviolet irradiation section 31 irradiates ultraviolet rays V. Thus, the oxygen gas is changed into the ozone gas.
Then, the ozone gas from the ultraviolet irradiation unit 31 is dissolved in pure water by the hollow fiber membrane 34 to regenerate the ozone water.
[0035]
Here, after the regenerated ozone water is added to the ozone water flowing in the ozone water supply pipe 21 at the junction G, the ozone concentration of the ozone water is measured.
By feeding back the measured ozone concentration to the ozone concentration control means 16, the concentration of ozone water to be regenerated by the ozone water regenerating means 14 or the supply amount of ozone water supplied from the ozone water regenerating means 14 is adjusted.
Thereby, the ozone concentration of the ozone water supplied to the substrate processing means 12 is adjusted. In this way, the ozone water whose ozone concentration is adjusted is supplied to the substrate disposed in the substrate processing means 12, and the substrate is processed.
[0036]
According to such a substrate processing apparatus and a substrate processing method, ozone gas and oxygen gas generated from ozone water are separated from ozone water while flowing through the ozone water supply pipe 21 by the plurality of gas-liquid separation means 13. In addition, it is possible to suppress the flow of the ozone water together with the gas, and to maintain the ozone water in a state where it can easily flow.
[0037]
Further, ozone water is regenerated from ozone gas and oxygen gas separated from the gas-liquid separation unit 13 by the ozone water regenerating unit 14 and ozone gas not completely dissolved in pure water by the ozone water generating unit 11. Since the regenerated ozone water is supplied to the junction G closer to the substrate processing means 12 of the ozone water supply pipe 21 by the regenerated ozone water supply pipe 26, the ozone concentration of the ozone water during the flow in the ozone water supply pipe 21 Can be compensated for.
Therefore, the ozone water generated by the ozone water generation unit 11 can be supplied to the substrate processing unit 12 while maintaining the ozone concentration.
[0038]
Further, in the present embodiment, the ozone concentration measuring means 15 measures the ozone concentration of the ozone water after the confluence point G in the ozone water supply pipe 21, and based on the measurement result, the ozone water regenerating means Since the concentration of the ozone water to be regenerated at 14 or the supply amount of the ozone water supplied from the ozone water regenerating means 14 is controlled, the ozone concentration of the ozone water supplied to the substrate disposed on the substrate processing means 12 is desired. The substrate can be cleaned by adjusting the concentration of the substrate.
[0039]
In the present embodiment, an example in which one substrate processing mechanism 17 is provided for the ozone water generating means 11 has been described. However, the present invention is not limited to this, and as shown in FIG. A mechanism 17 may be provided.
In this case, it is assumed that the gas-liquid separation unit 13 and the ozone water regenerating unit 14 are provided close to one substrate processing mechanism 17.
Here, the number of the gas-liquid separation means 13 is one, but a plurality of gas-liquid separation means 13 are preferably provided in the ozone water supply pipe 21 according to the distance from the ozone water generation means 11.
[0040]
With such a configuration, the ozone concentration of the ozone water supplied to the substrate processing means 12 (see FIG. 1) in each of the substrate processing mechanisms 17 can be adjusted by setting the ozone concentration to different concentrations. Processing can be performed at an ozone concentration suitable for each processing.
Further, even in the case where a plurality of substrate processing mechanisms 17 are provided, only one ozone water generation unit 11 needs to be provided. The generation means 11 may not be provided. Since the ozone water generating means 11 is expensive, such a configuration is advantageous in cost.
[0041]
Further, in the present embodiment, the cleaning process of the semiconductor substrate has been described as an example. However, the present invention is not limited to this. The present invention is also applicable to a case where a resist film formed on a semiconductor substrate or a liquid crystal substrate is removed or an oxide film is formed on the surface of such a substrate.
Further, in the present invention, the ozone-dissolved water obtained by dissolving ozone in pure water is defined as ozone water, but the present invention is not limited to pure water, but may be a chemical solution in which other acid or the like is added to pure water or a solvent. You may.
[0042]
【The invention's effect】
As described above, according to the substrate processing apparatus of the present invention, the gas-liquid separation unit can suppress the flow of the ozone water in the ozone water supply pipe together with the gas, so that the ozone water can easily flow. It is possible to maintain.
Further, the ozone water can be regenerated by using the ozone gas and the oxygen gas generated from the ozone water by the ozone water regenerating means. Since the ozone water is supplied, it is possible to compensate for the decrease in the ozone concentration of the ozone water while flowing through the ozone water supply pipe.
Therefore, it is possible to supply the ozone water generated by the ozone water generation means to the substrate processing means while maintaining the ozone concentration.
[0043]
Further, according to the substrate processing method of the present invention, ozone water is regenerated from ozone gas and oxygen gas generated from ozone water, and the regenerated ozone water is added to the separated ozone water, thereby reducing the ozone concentration. Can be supplemented. Therefore, the substrate can be processed while maintaining the ozone concentration of the ozone water.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an example of a substrate processing apparatus of the present invention (part 1).
FIG. 2 is an enlarged view of a main part of an example of the substrate processing apparatus of the present invention (part 1).
FIG. 3 is an enlarged view of a main part of an example of the substrate processing apparatus of the present invention (part 2).
FIG. 4 is a schematic configuration diagram of an example of a substrate processing apparatus of the present invention (part 2).
[Explanation of symbols]
11 ozone water generating means, 12 substrate processing means, 13 gas-liquid separating means, 14 ozone water regenerating means, 16 ozone concentration control means, 21 ozone water supply pipe, 26 regenerated ozone water supply pipe, 33 ... Ultraviolet irradiation means

Claims (6)

Ozone water generating means for generating ozone water,
Substrate processing means for supplying ozone water and processing the substrate,
An ozone water supply pipe for supplying ozone water from the ozone water generation means to the substrate processing means,
A gas-liquid separation unit provided on the ozone water supply pipe, for separating ozone water and ozone gas generated from the ozone water from the ozone water;
An ozone water regenerating unit that is provided close to the substrate processing unit and regenerates ozone water from the ozone gas and the oxygen gas separated by the gas-liquid separating unit;
A substrate processing apparatus, comprising: a regenerated ozone water supply pipe for supplying regenerated ozone water at a position closer to the substrate processing means than the ozone water regenerating means and closer to the substrate processing means. Based on the ozone concentration of the ozone water supplied to the substrate processing unit from the ozone water supply pipe, the ozone concentration of the ozone water regenerated by the ozone water regeneration unit or the ozone water supplied from the ozone water regeneration unit 2. The substrate processing apparatus according to claim 1, further comprising an ozone concentration control means for controlling a supply amount. 2. The substrate processing apparatus according to claim 1, wherein a plurality of said gas-liquid separation means are provided along said ozone water supply pipe. 2. The substrate according to claim 1, comprising a plurality of said substrate processing means, and one ozone water regenerating means and at least one gas-liquid separating means for each of said substrate processing means. Processing equipment. 2. The substrate processing apparatus according to claim 1, wherein the ozone water regenerating unit includes an ultraviolet irradiation unit. A substrate processing method for processing a substrate by supplying ozone water,
After the ozone gas and oxygen gas generated from the ozone water are separated from the ozone water in the middle of the ozone water supply path,
Ozone water is regenerated from the ozone gas and the oxygen gas, and the regenerated ozone water is added to the separated ozone water downstream of the supply path to adjust the concentration of the ozone water supplied to the substrate. A substrate processing method, comprising:

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