JP2008311591A - Substrate treatment method and substrate treatment equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate treating device capable of removing a residual organic matter on a substrate safely and in a short time, and a method. <P>SOLUTION: Cooled deionized water or ozone cold water is mixed with ozone gas to dissolve ozone, the low-temperature and high-concentration ozone water whose concentration has been increased is headed by a heating means 3, the high-temperature and high-concentration ozone water is supplied to a sealed substrate treatment tub 25 to be exposed to pressure higher than atmospheric pressure, thereby reducing an amount of useless ozone gas generated from the ozone water by heating exceeding saturated solubility, and expediting the reaction of the high-temperature and high-concentration ozone water by ozone. In the substrate treatment tub 25, the high-temperature and high-concentration ozone water is fluidized by the pump P2 to make an ozone concentration in the tank uniform. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention removes residual organic substances such as a resist adhering to the surface of a substrate such as a semiconductor wafer or a glass substrate used in these elements and components in a production process of the semiconductor elements, liquid crystal display elements, and electronic circuit components, for example. Therefore, the present invention relates to a substrate processing apparatus and method that can be suitably implemented.

  Among substrates used for elements such as semiconductor elements and liquid crystal display elements and electronic components, for example, semiconductor wafers are formed on the surface of the substrate in the production process by chemical vapor deposition (CVD) or sputtering ( A thin film (oxide film) is formed by the PVD method, a photoresist is applied on the thin film, the substrate is exposed and developed, and a mask pattern is formed by the resist. Then, using the mask pattern as a protective film, unnecessary thin films are removed by etching, and then impurities are introduced by ion implantation to form a diffusion layer.

  When etching or ion implantation is completed, the resist that is no longer needed is removed. As a method for removing the resist, for example, the resist is mixed with a mixture of an acid such as sulfuric acid and a peroxide, or various chemicals such as an organic solvent. Many methods are used for decomposing or dissolving them.

  Also, in the case of a resist that has been severely altered by high-concentration ion implantation or the like, it cannot be removed only with a chemical solution, and therefore, a plasma ashing process is used at a low pressure. In any case, a chemical solution is used to remove the residual resist.

However, the removal of residual resist with a chemical solution as described above is highly dangerous in terms of work and management because the chemical solution to be used is sulfuric acid, etc., and it is necessary to treat the waste liquid after use. Since there is a problem of contamination, in recent years, from the viewpoint of environmental protection and safety during work, as one of the methods that do not use chemicals with such a problem, there is a processing technology using ozone (O ₃ ). It has been adopted.

  Resist removal with ozone involves exposing a substrate with residual organic matter such as the resist to ozone gas or an ozone-dissolved solution, and decomposing the organic matter with strong oxidizing power due to ozone. Although it can fully meet the demands of environmental protection and safety during work, the removal of residual organic substances on the substrate surface by ozone does not cause environmental pollution and safety issues like when using chemicals, There is a problem in work efficiency that a long processing time is required.

  For example, Patent Document 1 proposes a conventional technique for solving such a problem. In this prior art, a substrate is immersed in ozone water stored in a processing tank, ozone is dissolved in pure water or ozone water cooled to about 0 ° C. to about 20 ° C. to generate high-concentration ozone water, and its low temperature The high-concentration ozone water is heated to about 20 ° C. to about 40 ° C. in the treatment tank, thereby improving the reaction rate between the organic matter adhering to the substrate and ozone and quickly removing the remaining organic matter adhering to the substrate. Has been proposed.

  In addition, in this prior art, it has been proposed to lower the freezing point of ozone water and to further increase the ozone concentration of ozone water by dissolving solvents such as sodium chloride, potassium chloride and calcium carbonate in ozone water. Yes.

Japanese Patent No. 3691985

  In the prior art of Patent Document 1 described above, the liquid level of the treatment tank is open to the atmosphere, and ozone that exceeds the saturation solubility under atmospheric pressure after heating becomes bubbles in ozone water, causing a decrease in the ozone concentration of ozone water. , Reaction efficiency decreases. Furthermore, when this ozone water is circulated in the treatment tank, it is mixed with the ozone water supplied next, further reducing the concentration, resulting in further deterioration in reaction efficiency, and the throughput per unit time, that is, throughput. There is a problem that decreases.

  An object of the present invention is to provide a substrate processing apparatus and method capable of removing residual organic substances on a substrate safely and in a short time.

The present invention provides a substrate processing apparatus for removing residual organic substances remaining on the surface of a substrate by immersing the substrate in ozone water.
High-concentration ozone water generating means for generating ozone gas having a pressure higher than atmospheric pressure and dissolving the ozone gas in low-temperature pure water or ozone water to generate high-concentration ozone water;
High-concentration ozone water heating means for heating the pressurized / high-concentration ozone water generated by the high-concentration ozone water generation means;
A substrate processing tank in which pressurized high-concentration ozone water is stored, and the substrate is immersed in the stored high-concentration ozone water for cleaning,
Ozone gas supply means for guiding a part of the ozone generated by the high-concentration ozone water generation means into the substrate processing tank;
A substrate processing apparatus comprising: a pressure control valve that maintains a gas phase pressure in the substrate processing tank at a predetermined pressure higher than atmospheric pressure.

  According to the present invention, when removing the residual organic matter remaining on the substrate by immersing the substrate in ozone water, the high concentration ozone water generating means dissolves the generated ozone gas in low temperature pure water or ozone water. To generate high-concentration ozone water. This high concentration ozone water is heated by the high concentration ozone water heating means and stored in the substrate storage tank. Part of the ozone gas generated by the high-concentration ozone water generating means is introduced into the substrate processing tank by the ozone gas supply means. Further, the pressure of the gas phase in the substrate processing tank is maintained at a predetermined pressure higher than the atmospheric pressure by the pressure control valve, thereby suppressing a decrease in the dissolved amount of ozone water stored in the substrate processing tank. Residual deposits on the substrate can be removed safely and in a short time with high-concentration ozone water.

  Further, the present invention is characterized by including fluidizing means for fluidizing the ozone water in the substrate processing tank.

  According to the present invention, since the ozone water in the substrate processing tank is fluidized by the fluidizing means, the removal of residual organic substances on the substrate surface is promoted.

  Furthermore, the present invention is characterized by comprising fluidizing means for circulating and fluidizing ozone water in the substrate processing tank in a pressurized state.

  According to the present invention, the ozone water in the substrate processing tank is fluidized in a pressurized state by the fluidizing means, so that the removal of residual organic substances on the substrate surface is promoted.

  Furthermore, the present invention includes a substrate holding unit that is provided in the substrate processing tank and holds the one or more substrates by supporting a peripheral portion of the one or more substrates.

  According to the present invention, since one or a plurality of substrates are held in the substrate processing tank in a state where only the peripheral portion is supported by the substrate holding means, the surface of the substrate is not covered by the substrate holding means, and therefore Residual organic substances can be reliably removed by bringing ozone water into contact with the entire surface.

Furthermore, the present invention provides a high concentration ozone water supply means for supplying the high concentration ozone water generated by the high concentration ozone water generation means from the bottom of the substrate processing tank into the substrate processing tank,
And ozone water discharging means for discharging ozone water stored in the substrate processing tank from the bottom of the substrate processing tank.

  According to the present invention, the high-concentration ozone water generated by the high-concentration ozone water generating means is supplied from the bottom of the substrate processing tank into the substrate processing tank by the high-concentration ozone water supply means, and the ozone water in the substrate processing tank is supplied. Is discharged from the bottom of the substrate processing tank by the ozone water discharging means, so the ozone water supplied from the bottom of the substrate processing tank forms an upward flow in the substrate processing tank and is discharged from the bottom of the substrate processing tank. As a result, a downward flow is formed in the substrate processing tank, and ozone water having a reduced concentration is discharged out of the system together with the bottom sediment, which is a reaction product of residual organic matter with ozone, and efficiently from the substrate in the substrate processing tank. Residual organic matter can be removed.

Furthermore, the present invention provides a high-concentration ozone water supply means for supplying the high-concentration ozone water generated by the high-concentration ozone water generation means from the side of the substrate processing tank into the substrate processing tank,
And ozone water discharging means for discharging ozone water stored in the substrate processing tank from the bottom of the substrate processing tank.

  According to the present invention, the high-concentration ozone water generated by the high-concentration ozone water generation means is supplied from the side of the substrate processing tank into the substrate processing tank by the high-concentration ozone water supply means, and the ozone in the substrate processing tank is supplied. Since water is discharged from the bottom of the substrate processing tank by the ozone water discharging means, the ozone water supplied from the side of the substrate processing tank forms an upward flow and a downward flow in the substrate processing tank, and the substrate processing By discharging from the bottom of the tank, a downward flow is formed in the substrate processing tank, and ozone water having a reduced concentration is discharged out of the system together with the bottom sediment, which is a reaction product of residual organic matter with ozone. Residual organic substances can be efficiently removed from the inner substrate.

Furthermore, the present invention provides a substrate processing method for removing residual organic matter remaining on the surface of the substrate by immersing the substrate in ozone water.
A high-concentration ozone water generation step of dissolving ozone gas in pure water or ozone water to generate high-concentration ozone water;
A high concentration ozone water heating step for heating the high concentration ozone water generated by the high concentration ozone water generation step;
The substrate processing tank is configured to store high-concentration ozone water pressurized by the high-concentration ozone water heating process in the substrate processing tank, and guide a part of the ozone gas used in the high-concentration ozone water generating means into the substrate processing tank. And a substrate cleaning step of cleaning the substrate by immersing the substrate in high-concentration ozone water stored in a substrate processing tank while maintaining the pressure of the gas phase inside at a predetermined pressure higher than atmospheric pressure. This is a substrate processing method.

  According to the present invention, high-concentration ozone water generated by dissolving ozone gas in pure water or ozone water is heated, and this pressurized high-concentration ozone water is stored in a substrate processing tank, and this substrate processing tank Since the pressure of the gas phase in the substrate processing tank is maintained at a predetermined pressure higher than the atmospheric pressure while guiding part of the ozone gas used in the high-concentration ozone water generating means, the ozone water in the substrate processing tank The residual organic matter adhering to the substrate can be removed by suppressing the decrease in ozone concentration.

  According to the present invention, unlike the prior art, ozone water is used to remove residual organic substances on the substrate without using a complicated and expensive apparatus having a chemical evacuation system such as sulfuric acid or a vacuum exhaust system. The time required for the removal can be shortened, and the efficiency of the removal process of the residual organic matter attached to the substrate can be improved.

  FIG. 1 is a system diagram showing a substrate processing apparatus 1 according to an embodiment of the present invention. The substrate cleaning method of the present invention is carried out by this substrate processing apparatus 1. The substrate processing apparatus 1 according to the present embodiment includes a high-concentration ozone water generation unit 2 that generates high-concentration ozone water at a low temperature, a heating unit 3 that heats the high-concentration ozone water, and ozone water heated in the heating unit 3. Substrate processing means 4 for removing organic substances adhering to the substrate W and pressurizing means 5 for suppressing a decrease in the concentration of ozone water in the substrate processing means 4 are included.

Examples of the substrate W to be processed include a semiconductor substrate such as a silicon wafer and a glass substrate of a liquid crystal display element. In the present embodiment, the substrate W is illustratively 8 inches to 12 inches.
Inch large-diameter silicon wafer, a resist is applied to the surface of the silicon wafer by a vapor deposition method (CVD method), and a mask pattern is formed through an exposure process and a development process. A case will be described in which an unnecessary thin film remaining as a residual organic substance is removed after etching an unnecessary thin film as a protective film and diffusing impurities by ion implantation. The resist is made of a photo-curing resin containing, for example, a phenol novolac resin or a cresol novolac resin as a curing agent.

  The high-concentration ozone water generating means 2 supplies the ejector 9 with the ozone gas generated by the ozone gas generator 10 from the pipe 11 and dissolves the ozone gas in the ozone water circulating from the dissolution tank 12 through the pipes 13, 14 and 15. Then, while increasing the concentration, pure water or ozone water cooled by the cooler 16 is supplied to the conduit 14 and replenished to generate low-temperature high-concentration ozone water. The generated low-temperature high-concentration ozone water is supplied to the heating means 3 from the dissolution tank 12 through the supply pipe 17.

  The ozone gas generator 10 supplies a source gas such as oxygen gas or air between an induction electrode provided on a dielectric and a discharge electrode, for example, and oxygen molecules are discharged by applying a high voltage between the induction electrode and the discharge electrode. May be realized by a configuration in which ozone gas is generated by dissociating the electrons into atoms and atoms.

  The ejector 9 has an input port connected to the conduit 13 connected to the bottom of the dissolution tank 12 and the conduit 14 connected to an outlet port. In the middle of the pipe line 14, a pipe line 19 for supplying pure water or ozone water having a temperature of about 4 ° C. or more and about 15 ° C. or less cooled by the cooler 16 is connected. Pure water or ozone water corresponding to consumption is replenished.

  A pump P <b> 1 is interposed between the pipe line 14 connected to the output port of the ejector 9 and the pipe line 15 connected to the upper part of the dissolution tank 12. The pump P1 is configured to forcibly circulate ozone water in a circulation path formed by the dissolution tank 12, the conduit 13, the ejector 9, the conduit 14, the pump P1 and the conduit 15, and dissolve the ozone gas by the ejector 9, while High concentration ozone water having a concentration of 100 ppm or more and 300 ppm or less is generated.

  A pipe line 20 is connected to the upper part of the dissolution tank 12, and the pressure of the gas phase in the dissolution tank 12 is adjusted to the pipe line 20, and the heating means 3 is supplied from the dissolution tank 12 through the supply pipe line 17. A pressure control valve V1 is interposed in order to maintain the supply pressure of the ozone water supplied to a constant pressure of about 0.10 MPa to about 0.35 MPa.

  The heating means 3 heats the low-temperature high-concentration ozone water supplied from the supply pipe 17 to about 40 ° C. to about 90 ° C., preferably about 80 ° C. The heated high-temperature high-concentration ozone water is supplied to the substrate processing means 4 through the supply pipe 21. An opening / closing valve V5 is interposed in the supply pipe line 21. The opening / closing valve V5 is opened to supply high-temperature high-concentration ozone water from the heating means 3 to the substrate processing tank 25, and the opening / closing valve V5 is closed, thereby heating means. The supply of high-temperature high-concentration ozone water from 3 to the substrate processing tank 25 is shut off.

  FIG. 2 is a system diagram for explaining the configuration of the substrate processing means 4 and shows a side surface of the substrate processing tank 25 as viewed from the left side of FIG. The substrate processing means 4 includes a substrate processing tank 25, a circulation pipe 26 that guides stored ozone water taken from the bottom of the substrate processing tank 25 to a level below the upper surface of the substrate processing tank 25, and a circulation pipe 26. And a pump P2. The circulation line 26 and the pump P2 constitute a fluidizing means, and the ozone water in the substrate processing tank 25 is fluidized to promote the removal of residual organic substances on the substrate surface.

  In the substrate processing tank 25, the flange of the lid 27 is detachably mounted on the flange of the upper part of the processing tank main body 24 capable of accommodating the substrate W by a clamp member 28, and is hermetically and liquid-tightly sealed. An airtight space can be formed in the treatment tank 25.

  The processing tank body 24 has a pair of long side walls 29, 30 parallel to the substrate W accommodated therein, a pair of short side walls 31, 32 perpendicular to the side walls 29, 30, and each side wall 29. 30; 31 and 32, and a bottom portion 33 having a substantially quadrangular pyramid shape that tapers downward (downward in FIG. 1). At bottom 33, reaction products of residual organic matter adhering to substrate W with ozone and other suspended matters are collected as bottom sediment and discharged from a drain line 42 described later.

  Between each of the side walls 29, 30; 31, 32 and the bottom 33, a bottom plate 35 in which a large number of through holes 34 are formed is mounted, and the bottom plate 35 and each of the short side walls 31, 32 are provided with a substrate W. A plurality of support pieces 36 for supporting the peripheral edge portion of the substrate W and holding the substrate W in parallel with the long side walls 29 and 30 are provided. The plurality of support pieces 36 constitute a substrate holding means. Each support piece 36 has a V-shaped groove, and the peripheral portion of the substrate W is fitted into the groove, and the substrate W is supported in a state where the edge portion of the peripheral portion is in line contact or point contact. Since the substrate W is held by the substrate holding means composed of the plurality of support pieces 36 as described above, the surface of the substrate W is not covered. Therefore, the entire surface of the substrate W is brought into contact with the high-concentration ozone water to reliably remain. Organic matter can be removed.

  The pressurizing means 5 branches from the pipe 11 and a branch pipe 40 for guiding a part of the ozone gas generated by the ozone gas generator 10 of the high-concentration ozone water generating means 2 from the lid 27 into the substrate processing tank 25. And an on-off valve V2 interposed in the branch pipe 40, a pipe 44 connected to the lid 27 of the substrate processing tank 25, and a pressure control valve V3 interposed in the pipe 44.

  In the substrate processing tank 25, a liquid phase L made of stored high-temperature high-concentration ozone water and a gas phase V made of ozone gas accumulated above the liquid phase L are formed. In a state where the on-off valve V2 interposed in the branch pipe 40 is opened, ozone gas generated by the ozone gas generator 10 is supplied into the substrate processing tank 25 from above. In the state where the on-off valve V2 is closed, the supply of ozone gas from the ozone gas generator 10 is shut off. The pressure control valve V3 is set to a predetermined pressure at which the pressure of the gas phase V in the substrate processing tank 25 is higher than atmospheric pressure, for example, about 0.15 MPa to about 0.30 MPa.

  A drain line 42 is connected to a plurality of locations on the bottom of the substrate processing tank 25, and an open / close valve V <b> 4 is interposed in the drain line 42. The drain pipe 42 and the on-off valve V4 constitute ozone water discharging means.

  The low-temperature high-concentration ozone water generated by the high-concentration ozone water generation means 2 is heated by the heating means 3, and then the high-temperature high-concentration ozone water passes from the plurality of locations at the bottom of the substrate processing tank 25 via the pipe line 21. It is supplied into the substrate processing tank 25. Since the ozone water in the substrate processing tank 25 is discharged from the bottom of the substrate processing tank 25 by the drain line 42 of the ozone water discharge means, the ozone water supplied from the bottom of the substrate processing tank 25 is 25, an upward flow is formed within the substrate processing tank 25, and a downward flow is formed within the substrate processing tank 25 by discharging from the bottom of the substrate processing tank 25, resulting in a decrease in concentration along with bottom sediment that is a reaction product of residual organic matter with ozone. The discharged ozone water is discharged to the outside of the system, guided to a waste liquid treatment facility for waste liquid treatment, and residual organic substances are efficiently removed from the substrate W in the substrate treatment tank 25.

FIG. 3 is a diagram showing the dependence of ozone water solubility and ozone gas pressure on ozone saturation solubility in ozone water for removing residual organic matter using the substrate processing apparatus 1 shown in FIG. In FIG. 3, the horizontal axis indicates the temperature of ozone water, and the vertical axis indicates the saturated dissolution concentration of ozone in ozone water. By heating the low-temperature high-concentration ozone water by the heating means 3, the Arrhenius law expressed by the following equation 1;
ER = ACw × exp (−E · kT) (1)

Here, ER: Etching rate [%]
A: Frequency factor [sec ⁻¹ ]
Cw: ozone water concentration [ppm]
E: Activation energy [kJ]
k: Boltzmann constant [1.338065 × 10 ⁻²³ JK ⁻¹ ]
T: ozone water temperature [K]
Accordingly, the etching rate of the organic substance in the treatment tank increases.

  However, as can be seen from the dependence of the ozone saturation solubility in ozone water obtained from the Roth & Sullivan formula shown in FIG. 3 on the ozone water temperature and the ozone gas pressure, the saturation solubility decreases with heating under a constant pressure. Water causes a decrease in concentration, and further a decrease in concentration when the pressure is reduced to atmospheric pressure. As a result, ozone dissolved at a high concentration in the high-concentration ozone water generating means 2 escapes from the ozone water as bubbles, making it impossible to effectively use ozone, and as a result, the organic substance removal efficiency does not increase.

  FIG. 4 is a diagram showing the relationship between each temperature and ozone concentration when low-temperature high-concentration ozone water at 18 ° C. is heated to 80 ° C. by an experiment by the present inventors, and FIG. 5 is 18 ° C. by an experiment by the present inventors. It is a figure which shows the result of having confirmed the removal time required for a 4 micrometer resist removal using the high temperature high concentration ozone water which heated ozone water of each density | concentration of 80 degreeC. FIG. 6 is a graph showing the dependency of the 4 μm resist removal time on the flow rate of ozone water. 4 and 5, the horizontal axis represents the ozone concentration (ppm) of ozone water at 18 ° C., and the vertical axis represents the ozone concentration (ppm) of ozone water at 80 ° C. In FIG. 6, the horizontal axis represents the flow rate of ozone water (cm / min), and the vertical axis represents the removal time (min) of residual organic matter.

  As is clear from these experimental results, when low-temperature high-concentration ozone water is heated and washed under atmospheric pressure, ozone gas exceeding the saturation solubility does not dissolve in ozone water and does not contribute to the reaction with organic matter. I understand that it's wasted. It was also confirmed that by increasing the flow rate of ozone water relative to the organic matter, the reaction product of residual organic matter and ozone water on the substrate surface was replaced by ozone water, and the removal time was shortened.

  As described above, according to the present embodiment, the inside of the substrate processing tank 25 is pressurized, ozone that is wasted in the substrate processing tank 25 is reduced, the substrate processing is performed in a short time, and the flow rate of ozone water on the substrate surface is further reduced. The reaction product can be replaced with ozone water. In the embodiment shown in FIG. 1 and FIG. 2, the substrate processing tank 25 is held in the substrate processing tank 25, the substrate processing tank 25 is sealed, and filled with heated ozone water. While maintaining the pressure state of the ozone water, the ozone water is circulated in the substrate processing tank 25, and the replacement effect of the organic substance and the reaction product by the ozone in the ozone water on the substrate surface is enhanced by the flow of the ozone water. The substrate W in the substrate processing tank 25 may be configured to store a plurality of substrates with a space between each other, or a configuration in which a plurality of the substrate processing tanks 25 that store one substrate are connected in parallel. There may be. Such a configuration can also achieve the same effect as described above.

  FIG. 7 is a partial system diagram showing the substrate processing means 4a provided in the substrate processing apparatus 1 according to another embodiment of the present invention. Note that the same reference numerals are given to portions corresponding to the above-described embodiment. The pressurizing means 5 of the substrate processing apparatus 1 of the present embodiment includes a pressure control valve V3 for adjusting the pressure of ozone gas generated from high-temperature high-concentration ozone water having a saturation solubility or higher stored in the substrate processing tank 25. Only the pipe 41 to be connected is connected to the lid 27, and the gas phase V in the substrate processing tank 25 can be regulated from atmospheric pressure to a pressurized state. By adopting such pressurizing means 5, the conduit 40 and the on-off valve V2 for guiding the ozone gas from the ozone gas generator 10 to the substrate processing tank 25 can be omitted, and the configuration can be simplified.

  FIG. 8 is a partial system diagram showing the substrate processing means 4b provided in the substrate processing apparatus 1 according to still another embodiment of the present invention. The parts corresponding to those of the above-described embodiments shown in FIG. 1 to FIG. The substrate processing apparatus 1 according to the present embodiment has a configuration in which the substrate processing tank 25 itself is hermetically sealed and filled with high-temperature high-concentration ozone water as a configuration of the pressurizing unit 5. Maintaining the pressure state higher than the atmospheric pressure, circulating the high-concentration ozone water in the substrate processing tank 25 to fluidize the ozone water, and the fluidized ozone water causes the high-temperature and high-concentration ozone water to flow into the substrate W. It is forcibly brought into contact with the surface to increase the substitution efficiency between the organic substance and its reaction product by ozone in the ozone water. According to such a configuration, it is not necessary to connect the above-described pipe lines 40 and 41 to the lid body 27, and the on-off valve V2 and the pressure control valve V3 can be eliminated, and the configuration of the substrate processing apparatus 1 is simple. It becomes.

  FIG. 9 is a partial system diagram showing the substrate processing means 4c provided in the substrate processing apparatus 1 of still another embodiment of the present invention, and the substrate processing tank 25 shows a side surface as viewed from the left side of FIG. Note that the same reference numerals are assigned to the portions corresponding to the above-described embodiments shown in FIGS. In the substrate processing apparatus 1 of the present embodiment, after the high-concentration ozone water generated by the high-concentration ozone water generation unit 2 is heated by the heating unit 3, a plurality (three in the present embodiment) of pipelines 21a, 21 ( b) and 21c are fed into the substrate processing tank 25 from a plurality of locations on the long side walls 29 and 30 which are the side portions of the substrate processing tank 25.

  By adopting such a configuration, high-temperature and high-concentration ozone water supplied into the substrate processing tank 25 is supplied from a plurality of surfaces to the surface of the substrate W, and the high-temperature and high-concentration ozone water is uniformly applied to the surface of the substrate W. Can be supplied. The high-temperature and high-concentration ozone water having a substantially uniform concentration forms an upward flow and a downward flow along the surface of the substrate W, reacts with the remaining organic substances over the entire surface of the substrate W, and then reacts in a short residence time. At the same time, the organic matter is discharged from the drain line 42 and the remaining organic matter can be efficiently removed from the substrate W in the substrate processing tank 25.

  As described above, the present invention reduces the waste ozone gas more than the saturated solubility that comes out of the ozone water by heating by bringing the inside of the substrate processing tank 25 into a pressurized state higher than the atmospheric pressure, and the reaction product on the substrate surface. Can be quickly replaced by ozone water to promote the reaction of ozone. Therefore, the present invention can be applied not only to organic substance removal but also to an apparatus and method for processing a substrate using the oxidizing power of dissolved ozone in ozone water, such as an oxide film forming apparatus on the substrate surface.

  Further, the present invention may be configured such that the dissolved ozone gas concentration of the ozone water generated in the high-concentration ozone water generating means 2 is detected by an ozone water concentration detector provided in the supply pipe line 17 and monitored and managed. . In this case, the saturated dissolution concentration of ozone gas in water at normal pressure and room temperature is 50 to 60 ppm, but the dissolved ozone gas concentration of ozone water used for cleaning the substrate W is preferably higher in terms of cleaning effect. .

  Furthermore, the present invention is not particularly limited as a means for pressurizing the inside of the substrate processing tank 25 as long as the inside of the substrate processing tank 25 can be pressurized higher than the atmospheric pressure. Further, as the pumps P1 and P2, a pressure pump having high oxidation resistance using an ozone-resistant gas material is preferably used.

  Furthermore, in another embodiment of the present invention, the substrate processing means 4 may have a configuration to which means for irradiating ultraviolet rays is added. By irradiating the substrate W immersed in the high-temperature and high-concentration ozone water in the substrate processing tank 25 with ultraviolet rays, the decomposition rate of ozone is accelerated, and the cleaning effect can be increased accordingly. Therefore, a higher cleaning effect can be obtained by using both high-temperature and high-concentration ozone water and ultraviolet irradiation. The means for irradiating the ultraviolet rays is not particularly limited, and examples thereof include a UV lamp. Moreover, it is preferable that the wavelength of the irradiated ultraviolet ray is around 254 nm which ozone absorbs.

  Furthermore, in another embodiment of the present invention, means for adding an acidic compound or an organic solvent or both to high-temperature and high-concentration ozone water supplied to the substrate processing tank 25 may be provided. By adding an acidic compound and / or an organic solvent to high-temperature and high-concentration ozone water, the cleaning effect can be improved. Examples of the acidic compound include sulfuric acid, hydrochloric acid, nitric acid, and hydrofluoric acid. Examples of the organic solvent include acetic acid, acetone and acetonitrile.

  In each of the above-described embodiments, the structure in which the substrate W removes residual organic substances attached to the semiconductor wafer has been described. It may be suitable for cleaning various substrates using high oxidizing power by high-temperature high-concentration ozone water.

1 is a system diagram showing a substrate processing apparatus 1 according to an embodiment of the present invention. It is a systematic diagram for demonstrating the structure of the substrate processing means 4, and shows the side surface which looked at the substrate processing tank 25 from the left side of FIG. It is a figure which shows the dependence of ozone water temperature and ozone gas pressure of the ozone saturation solubility in ozone water for a residual organic substance to be removed using the substrate processing apparatus 1 shown by FIG. It is a figure which shows the relationship between each temperature and ozone concentration when 18 degreeC low temperature high concentration ozone water is heated to 80 degreeC by experiment by this inventor. It is a figure which shows the result of having confirmed the removal time required for resist removal of 4 micrometers using the high temperature high concentration ozone water which heated ozone water of each concentration of 18 degreeC to 80 degreeC by experiment by this inventor. It is a figure which shows the dependence of the resist removal time of 4 micrometers by the flow velocity of ozone water. It is a one part systematic diagram which shows the substrate processing means 4a with which the substrate processing apparatus 1 of other embodiment of this invention is equipped. It is a one part systematic diagram which shows the substrate processing means 4b with which the substrate processing apparatus 1 of other embodiment of this invention is equipped. It is a partial systematic diagram which shows the substrate processing means 4c with which the substrate processing apparatus 1 of further another embodiment of this invention is equipped, and shows the side surface seen from the left side of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate processing apparatus 2 High concentration ozone water production | generation means 3 Heating means 4, 4a, 4b, 4c Substrate treatment means 5 Pressurization means 9 Ejector 10 Ozone gas generator 11, 13, 14, 15, 20 Pipe line 12 Dissolution tank 16 Cooling Containers 17, 21 Supply pipe 25 Substrate processing tank 26 Circulation pipe 24 Processing tank main body 27 Cover body 28 Clamp member 29, 30 Long side wall 31, 32 Short side wall 33 Bottom part 34 Through hole 35 Bottom plate 36 Support piece 40 Branch line 42 Drain line P1, P2 Pump V1, V3 Pressure control valve V2, V4, V5 On-off valve W Substrate

Claims (7)

In a substrate processing apparatus for removing residual organic matter remaining on the surface of the substrate by immersing the substrate in ozone water,
High concentration ozone water generating means for generating ozone gas having a pressure higher than atmospheric pressure and dissolving the ozone gas in low temperature pure water or ozone water to generate high concentration ozone water;
High-concentration ozone water heating means for heating the high-concentration ozone water generated by the high-concentration ozone water generation means;
A substrate processing tank in which pressurized high-concentration ozone water is stored, and the substrate is immersed in the stored high-concentration ozone water for cleaning,
Ozone gas supply means for guiding a part of the ozone gas generated by the high-concentration ozone water generation means into the substrate processing tank;
A substrate processing apparatus comprising: a pressure control valve that maintains a gas phase pressure in the substrate processing tank at a predetermined pressure higher than atmospheric pressure.   2. The substrate processing apparatus according to claim 1, further comprising fluidizing means for fluidizing ozone water in the substrate processing tank.   2. The substrate processing apparatus according to claim 1, further comprising fluidizing means for circulating and fluidizing ozone water in the substrate processing tank in a pressurized state.   4. A substrate holding unit that is provided in the substrate processing tank and holds the one or more substrates by supporting a peripheral portion of the one or more substrates. The substrate processing apparatus as described in one. High-concentration ozone water supply means for supplying the high-concentration ozone water generated by the high-concentration ozone water generation means from the bottom of the substrate processing tank into the substrate processing tank;
The substrate processing according to any one of claims 1 to 4, further comprising ozone water discharging means for discharging ozone water stored in the substrate processing tank from a bottom portion of the substrate processing tank. apparatus. High-concentration ozone water supply means for supplying the high-concentration ozone water generated by the high-concentration ozone water generation means from the side of the substrate processing tank into the substrate processing tank;
The substrate processing according to any one of claims 1 to 4, further comprising ozone water discharging means for discharging the ozone water stored in the substrate processing tank from the bottom of the substrate processing tank. apparatus. In the substrate processing method of removing residual organic matter remaining on the surface of the substrate by immersing the substrate in ozone water,
A high-concentration ozone water generation step of dissolving ozone gas in pure water or ozone water to generate high-concentration ozone water;
A high-concentration ozone water heating step for heating the pressurized and high-concentration ozone water generated by the high-concentration ozone water generation step;
Pressurized high-concentration ozone water is stored in a substrate treatment tank, and a part of the ozone gas used in the high-concentration ozone water generating means is introduced into the substrate treatment tank, and the pressure of the gas phase in the substrate treatment tank is changed to atmospheric pressure. And a substrate cleaning step of cleaning the substrate by immersing the substrate in high-concentration ozone water stored in a substrate processing tank while maintaining a higher predetermined pressure.

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