JP6415100B2 - Method for treating exposed molybdenum substrate - Google Patents

Description

  The present invention relates to a method for processing a molybdenum-exposed substrate. In particular, the present invention relates to a method used for processing an integrated circuit substrate in which at least molybdenum or a molybdenum compound is exposed. Examples of substrates to be processed include semiconductor wafers, liquid crystal display substrates, plasma display substrates, field emission display substrates, optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, photomask substrates, A ceramic substrate is included.

  High integration and high speed of semiconductor integrated circuit elements are market demands. In order to meet this demand, lower resistance copper wiring has been used in place of the conventionally used aluminum wiring. If a multilayer wiring is formed by combining a copper wiring with a low dielectric constant insulating film (a so-called low-k film; an insulating film made of a material having a relative dielectric constant smaller than that of silicon oxide), an integrated circuit that operates at a very high speed. A circuit element can be realized.

  In the manufacturing process of such integrated circuit elements, cleaning is performed for the purpose of removing fine particles, organic substances, metals, natural oxide films, etc. adhering to the surface of an object to be processed such as a wafer or a substrate, and a high degree of cleanliness is achieved. Achieving and maintaining this is important for maintaining product quality and improving yield. This cleaning is performed, for example, using a chemical solution such as a sulfuric acid / hydrogen peroxide solution mixed solution or a hydrofluoric acid solution, and rinsing with ultrapure water is performed after the cleaning. In recent years, the number of cleanings has increased due to miniaturization of semiconductor devices, diversification of materials, and complexity of processes. For example, in the formation of the multilayer wiring, a metal wiring serving as a first wiring layer is formed on a substrate, the metal wiring is filled with an insulating material, and the surface of the insulating material covering the metal wiring is planarized by CMP. Then, a procedure is repeated in which a metal wiring serving as a second wiring layer is formed on the surface, the metal wiring is filled with an insulating material, and the surface of the insulating material is flattened by CMP. In such a process, the substrate is cleaned every time the polishing step is completed.

  For the production of ultrapure water, an ultrapure water production apparatus comprising a pretreatment system, a primary pure water system, and a secondary pure water system (subsystem) is generally used. The role of each system in the ultrapure water production system is as follows. The pretreatment system is a process for removing suspended substances and colloidal substances contained in raw water by, for example, coagulation sedimentation or sand filtration. The primary pure water system uses, for example, an ion exchange resin or a reverse osmosis (RO) membrane to remove the ionic components and organic components of the raw water from which the suspended substances have been removed by the pretreatment system. This is a process for obtaining water. As shown in FIG. 1, the subsystem includes an ultraviolet oxidizer (UV), a membrane deaerator (MD), a non-regenerative ion exchanger (eg, cartridge polisher (CP)), and a membrane separator (eg, ultrafiltration). This is a process for producing ultrapure water by further increasing the purity of primary pure water obtained by the primary pure water system using a water flow line in which a device (UF)) and the like are made continuous.

  When the ultrapure water obtained in this way is used for cleaning a semiconductor substrate, there are the following various problems, and countermeasures have been proposed for each problem.

  If the concentration of dissolved oxygen contained in the cleaning water is high, a natural oxide film is formed on the wafer surface by the cleaning water, thereby preventing precise control of the film thickness and film quality of the gate oxide film, contact holes, vias, and plugs. The contact resistance such as may increase. Further, the wiring metal is exposed on the surface of the substrate that is cleaned after the polishing step in the multilayer wiring forming process. Since wiring metals such as W and Cu are metals that are easily corroded by oxygen dissolved in water, the thickness of the wiring may be reduced during the cleaning of the substrate with the ultrapure water. In addition, when the resist residue on the substrate surface caused by polishing is removed by the polymer removal liquid, the polymer removal liquid touches the air in the cleaning chamber, and oxygen dissolves in the polymer removal liquid, so that the polymer removal liquid having a high oxygen concentration. Is supplied to the substrate. Even in this case, the metal film (copper film, tungsten film, etc.) on the substrate is oxidized by the dissolved oxygen in the polymer removing solution, and there is a possibility that the performance of the integrated circuit element formed from the substrate is deteriorated.

  As a countermeasure against these problems, the above-described subsystem performs degassing using a membrane deaerator to reduce the amount of gas dissolved in water, but it is described in Patent Document 1 and Patent Document 2 as well. In order to reduce dissolved oxygen in water, an inert gas or hydrogen gas is added to degassed ultrapure water. Patent Document 1 also employs a method of replacing the atmosphere near the surface of the substrate to be cleaned with an inert gas.

  In the above-mentioned subsystem, water is also decomposed and removed by irradiating water with ultraviolet rays using an ultraviolet oxidizer, so that water molecules are also oxidized by this ultraviolet irradiation, producing hydrogen peroxide, an oxidizing substance. Is done. That is, the ultrapure water contains hydrogen peroxide.

  As a method of removing hydrogen peroxide in water, a method of removing hydrogen peroxide in water using a platinum group metal catalyst such as Pd is known. In particular, as described in Patent Document 3, a catalyst in which a platinum group metal is supported on a monolithic organic porous anion exchanger and a water to be treated containing hydrogen peroxide are brought into contact with each other. There is also a method for efficiently decomposing and removing hydrogen peroxide from water. Patent Document 4 discloses a method in which hydrogen is dissolved in oxygen-dissolved water and then the hydrogen-dissolved water is contacted with a catalyst in which a platinum group metal is supported on a monolithic organic porous anion exchanger. In the method described in Patent Document 4, water to be treated from which dissolved hydrogen peroxide and oxygen are removed with high efficiency can be produced.

JP 2010-56218 A JP 2003-136077 A JP 2010-240641 A Japanese Patent No. 2010-240642

  By the way, with the miniaturization of the pattern dimensions of the integrated circuit element, disconnection due to a force applied in a thermal process and disconnection due to an increase in current are regarded as problems. For this reason, aluminum, copper, or the like is used for wiring between the elements, and molybdenum, tungsten, or the like is used on the substrate as the refractory metal for the gate electrode of the MOS type element.

  As the pattern dimensions of the integrated circuit element are further miniaturized, the thickness of the wiring is becoming thinner, and there is a concern that a slight corrosion of the wiring deteriorates the performance of the integrated circuit element.

  Since copper, molybdenum, tungsten, etc. are metals that are easily corroded by dissolved oxygen, dissolved oxygen in the processing solution applied to the substrate for the purpose of cleaning and etching can be used as much as possible by using the techniques described above. It is thought to be reduced.

  However, when processing a substrate with copper, molybdenum, tungsten, etc. exposed on the surface using hydrogen water from which dissolved oxygen was removed, it was found that corrosion of molybdenum was not suppressed.

  Therefore, as a result of the analysis by the inventors as shown in the Examples section of this specification, molybdenum was corroded not only by oxygen in the treatment solution but also by hydrogen peroxide (10 to 50 μg / L level) and eluted. I found out. In the ultrapure water production apparatus (subsystem) described above, for the first time, it was found that hydrogen peroxide was generated in water by an ultraviolet oxidation apparatus, which caused corrosion.

  Furthermore, the present inventors also found that when oxygen is contained in the treatment liquid, hydrogen peroxide, which is a causative substance of corrosion, is generated when the oxygen and molybdenum come into contact with each other.

  In other words, the applicant completely eliminates the corrosion of molybdenum and molybdenum compounds exposed on the surface of the workpiece by simply removing the dissolved oxygen in the water when the substrate is treated with ultrapure water irradiated with ultraviolet rays. I found that I could not suppress it.

  Therefore, the present invention has been made in view of the above problem, and provides a method for treating a molybdenum-exposed substrate that can further suppress corrosion of molybdenum exposed on the substrate surface.

One aspect for achieving the above object relates to a method of processing a molybdenum-exposed substrate. In this method, a substrate having at least molybdenum or a molybdenum compound exposed on the surface is disposed in the processing chamber, and the hydrogen peroxide concentration dissolved in the solution is adjusted to 2 μg / L or less and the dissolved oxygen concentration is adjusted to 2 μg / L or less. And a step of processing the substrate in the processing chamber with the processing liquid, and the step of generating the processing liquid branches from the main pipe connected to the subsystem of the ultrapure water production apparatus. A platinum group metal catalyst, which is a monolithic organic porous anion exchanger supported on a monolithic organic porous anion exchanger, is installed on the treatment liquid supply pipe connected to the treatment chamber. It includes passing hydrogen-dissolved water obtained by adding hydrogen to water through a platinum group metal catalyst to produce a hydrogen-dissolved treatment liquid as a treatment liquid .

  As described above, according to the present invention, it is possible to further suppress the molybdenum and molybdenum compound exposed on the substrate surface from being corroded by the substrate processing liquid, as compared with the prior art. Therefore, it is possible to provide a substrate processing that hardly degrades the performance of the manufactured integrated circuit element.

It is a schematic diagram which shows the general aspect of the manufacturing apparatus of ultrapure water. 1 is a schematic configuration diagram of a substrate processing apparatus according to a first embodiment. The figure which shows the piping line which supplies a process liquid from the subsystem shown in FIG. 1 to the substrate processing apparatus of this invention. The figure which shows the deformation | transformation aspect 1 of the substrate processing apparatus which concerns on 1st embodiment. The figure which shows the deformation | transformation aspect 2 of the substrate processing apparatus which concerns on 1st embodiment. The figure which shows the deformation | transformation aspect 3 of the substrate processing apparatus which concerns on 1st embodiment. The figure which shows the deformation | transformation aspect 4 of the substrate processing apparatus which concerns on 1st embodiment. The figure which shows the deformation | transformation aspect 5 of the substrate processing apparatus which concerns on 1st embodiment. The figure which shows the preferable aspect of piping used for the substrate processing apparatus which concerns on this invention. It is a typical block diagram of the substrate processing apparatus which concerns on 2nd embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First embodiment]
FIG. 2 is a schematic configuration diagram for explaining the configuration of the substrate processing apparatus according to the first embodiment. The substrate processing apparatus 1 of the first embodiment is a single-wafer type apparatus that processes substrates W one by one. In this embodiment, the substrate W is a circular substrate such as a semiconductor wafer.

  Referring to FIG. 2, the substrate processing apparatus 1 has one or a plurality of processing chambers 2 partitioned by a partition wall. In each processing chamber 2, a spin chuck 3 (substrate holding mechanism, substrate holding and rotating mechanism) that holds and rotates a single substrate W horizontally, and a processing liquid on the upper surface of the substrate W held by the spin chuck 3. And a treatment liquid nozzle 4 for supplying the liquid.

  The spin chuck 3 includes a disc-shaped spin base 8 (holding base) that is horizontally attached to an upper end of a rotating shaft extending in a vertical direction, a plurality of clamping members 6 disposed on the spin base 8, And a chuck rotation driving mechanism 7 coupled to the rotation shaft. The spin base 8 is a disk-shaped member having a diameter larger than that of the substrate W, for example. The upper surface of the spin base 8 (the surface of the holding base) is a circular plane having a diameter larger than that of the substrate W.

  The plurality of clamping members 6 can clamp (hold) one substrate W in a horizontal posture in cooperation with each other on the upper surface of the spin base 8. The substrate W held by the clamping member 6 is rotated around a vertical rotation axis passing through the center by the driving force of the chuck rotation driving mechanism 7.

  The processing liquid nozzle 4 can discharge a target processing liquid such as a cleaning process or etching onto the upper surface of the substrate W held by the spin chuck 3. The treatment liquid nozzle 4 is attached to the tip of a nozzle arm 19 that extends horizontally. The treatment liquid nozzle 4 is disposed above the spin chuck 3 with its discharge port directed downward.

  A support shaft 20 extending along the vertical direction is coupled to the nozzle arm 19. The support shaft 20 can swing around its central axis. The support shaft 20 is coupled to a nozzle swing drive mechanism configured by, for example, a motor. The treatment liquid nozzle 4 and the nozzle arm 19 are horizontally moved integrally around the central axis of the support shaft 20 by the driving force of the nozzle swing drive mechanism. Thereby, the processing liquid nozzle 4 can be disposed above the substrate W held by the spin chuck 3, and the processing liquid nozzle 4 can be retracted from above the spin chuck 3. Further, while the substrate W is rotated by the spin chuck 3, the processing liquid nozzle 4 is swung in a predetermined angle range while supplying the processing liquid droplets from the processing liquid nozzle 4 to the upper surface of the substrate W. Thus, the processing liquid supply position on the upper surface of the substrate W can be moved.

  A processing liquid supply pipe 27 is connected to the processing liquid nozzle 4 through the hollow arm 19 and the support shaft 20.

  The processing liquid supply pipe 27 is provided with a processing liquid valve 28 for switching between supply and stop of processing liquid supply to the processing liquid nozzle 4.

  Further, a gas supply pipe 39 is inserted into the processing chamber 2. Nitrogen gas, which is an example of an inert gas, is supplied into the processing chamber 2 from the gas supply pipe 39. Thereby, the air existing in the space above the substrate W can be replaced with the inert gas. For this reason, the inert gas is preferably supplied around the substrate W held by the spin chuck 3, particularly in the space between the processing liquid nozzle 4 and the spin chuck 3.

  The gas supply pipe 39 is provided with a gas valve 41 for switching between supply and stop of supply of the inert gas to the gap, and a gas flow rate adjustment valve 18 for adjusting the supply flow rate of the inert gas to the gap. ing.

  The opening / closing operation of each of the processing liquid valve 28, the gas valve 41, and the gas flow rate adjusting valve 18 is controlled by the control unit 5.

  Further, in the present invention, as shown in FIG. 3, the processing liquid (ultra pure water) from the subsystem 9 (see FIG. 1 for details) of the ultrapure water production apparatus is supplied to each processing chamber 2 (cleaning) of the substrate processing apparatus 1. Mechanism). The processing liquid outlet 9a of the subsystem 9 and the processing liquid inlet 1a of each substrate processing apparatus 1 are connected via a main pipe 10 made of a fluororesin such as PVC, PFA, or PTFE, which is mainly used in a semiconductor manufacturing line. Yes. Each main pipe 10 extends in each substrate processing apparatus 1 and branches, and is connected to a processing liquid supply pipe 27 that communicates with the processing liquid nozzle 4 of each processing chamber 2 in the substrate processing apparatus 1. The processing liquid supply pipe 27 is also made of a fluororesin such as PVC, PFA, or PTFE.

  Referring again to FIG. 2, the catalyst unit 21 is located between the portion of the main pipe 10 immediately adjacent to the processing liquid inlet 1 a or the first branch point 10 a of the main pipe 10 from the processing liquid inlet 1 a toward each processing chamber 2. And a membrane separation unit 22 are interposed.

  The treatment liquid supplied from the main pipe 10 to the catalyst unit 21 is adjusted to a hydrogen dissolution treatment liquid having a dissolved hydrogen concentration of 50 μg / L or more. The treatment liquid discharged from the subsystem 9 to the main pipe 10 is hydrogen-dissolved water having a predetermined dissolved hydrogen concentration, which is treated by a hydrogen dissolution treatment apparatus (see FIG. 1) included in the subsystem 9. However, when the dissolved hydrogen concentration of the hydrogen-dissolved water is less than 50 μg / L at the position immediately before the catalyst unit 21 in FIG. 2, hydrogen is added to the hydrogen-dissolved water and the dissolved hydrogen concentration of the hydrogen-dissolved water is Is adjusted to 50 μg / L or more. In this case, a hydrogen gas introducing device (not shown) is provided in the piping portion immediately before the catalyst unit 21.

  The catalyst unit 21 has an aspect in which a platinum group metal catalyst that reduces the dissolved oxygen concentration in the hydrogen dissolution treatment liquid obtained through the catalyst unit 21 to 2 μg / L or less and the hydrogen peroxide concentration to 2 μg / L or less is filled. For example, a catalyst unit filled with a palladium catalyst and a catalyst unit in which a palladium catalyst is supported on a monolith can be mentioned. More specific examples of the platinum group metal catalyst will be described later (third implementation). See form).

  The membrane separation unit 22 is disposed in a pipe portion from the catalyst unit 21 to the first branch point 10a, and includes a microfiltration membrane (MF), an ultrafiltration membrane (UF), or a nanofilter (NF).

  According to the aspect of the present invention, the following problems can be solved.

  Even when hydrogen-dissolved water in which dissolved oxygen is reduced is prepared by the subsystem 9, air passes through the pipe in the process of transferring the hydrogen-dissolved water from the subsystem 9 to the substrate processing apparatus 1 through the long pipe. The amount of dissolved oxygen in the hydrogen-dissolved water in the pipe will increase. When this hydrogen-dissolved water is used as a substrate processing solution, there is a problem that the wiring exposed on the surface of the substrate to be processed is corroded (that is, metal is eluted or oxidized). With the recent miniaturization of pattern dimensions, the film thickness of wiring made of copper, tungsten, molybdenum, etc. has also been reduced, so even a slight corrosion is expected to have a great influence on the performance of semiconductor circuit elements.

  In view of such problems, in the aspect of the present invention, the catalyst unit 21 and the hydrogen-dissolved water inlet of the substrate processing apparatus 1 or the inside (the processing liquid supply pipe 27 as close as possible to the processing chamber 2 in which the substrate W to be processed is disposed) and By providing a membrane separation unit 22 and a mechanism (gas supply pipe 39, gas valve 41, etc.) for filling the processing chamber 2 with an inert gas, the oxygen gas concentration on the surface of the substrate to be processed is reduced to a predetermined value or less. In the processing chamber 2, the substrate to be processed can be processed using a hydrogen-dissolving processing liquid in which oxygen and hydrogen peroxide are reduced to a predetermined value or less. For this reason, corrosion of the wiring exposed on the surface of the substrate to be processed can be further suppressed as compared with the conventional substrate processing apparatus.

<Deformation mode 1>
2 described above removes dissolved oxygen and hydrogen peroxide from hydrogen-dissolved water using a means including a catalyst unit 21 and a membrane separation unit 22, and then removes the hydrogen-dissolved treatment liquid from which each of them has been removed. Although it sends to the process chamber 2, this invention can also take the aspect of FIG. In the embodiment of FIG. 4, means including a catalyst unit 21 and a membrane separation unit 22 is installed for each processing liquid supply pipe 27 disposed in each processing chamber 2. According to this aspect, the means including the catalyst unit 21 and the membrane separation unit 22 can be disposed closer to the processing chamber 2 than in the aspect of FIG. For this reason, the piping from the membrane separation unit 22 of the means to the processing liquid nozzle 4 of the processing chamber 2 is also shortened, and therefore the probability that oxygen is contained in the processing liquid discharged to the substrate in the processing chamber 2 is further reduced. I can do it.

  Further, in the embodiment of FIG. 4, a drain pipe 23 is connected to a pipe portion from the membrane separation unit 22 to the treatment liquid valve 28. A drainage valve 24 for switching between drainage and drainage stop is interposed in the drainage pipe 23. The opening / closing operation of the drain valve 24 is also controlled by the control unit 5. When the distance from the processing solution nozzle 4 to the catalyst unit 21 in the processing chamber 2 is shortened as in the embodiment of FIG. 4, the hydrogen-dissolving processing solution stagnates in the catalyst unit 21 while the substrate processing in the processing chamber 2 is stopped. In this case, there is a possibility that impurities may elute into the processing liquid supply pipe 27. For this reason, when the substrate processing in the processing chamber 2 is stopped for a certain time, the hydrogen-dissolved processing liquid in the processing liquid supply pipe 27 is drained (blowed) from the drain pipe 23 and then a new hydrogen-dissolving processing liquid is supplied to the substrate W. It is made to supply.

  As another method of discharging impurities eluted into the processing liquid supply pipe 27, the processing liquid nozzle 28 is opened with the position of the processing liquid nozzle 4 being removed from the upper part of the substrate W, and the process liquid supply pipe 27 stays in the processing liquid supply pipe 27. A method for discharging the hydrogen-dissolving treatment liquid can also be used. In this case, the drain pipe 23 and the drain valve 24 are unnecessary.

<Deformation mode 2>
In the embodiment of FIG. 2 described above, after the dissolved oxygen and hydrogen peroxide are removed from the hydrogen-dissolved water using the means including the catalyst unit 21 and the membrane separation unit 22, the hydrogen-dissolved treatment liquid from which they have been removed is used for each of them. Although it has sent to the processing chamber 2, this invention can also take the aspect of FIG. That is, this is an embodiment in which a chemical solution is mixed with a hydrogen-dissolved processing solution from which dissolved oxygen and hydrogen peroxide have been removed to prepare diluted water, which is supplied to the processing solution nozzle 4. This is effective when a chemical solution that cannot be passed through the catalyst unit 21 is used.

  Referring to FIG. 5, a chemical liquid preparation unit 51 is added to the processing liquid supply pipe 27 in the mode shown in FIG.

  The chemical solution preparation unit 51 can mix the hydrogen-dissolved processing solution from which dissolved oxygen and hydrogen peroxide have been removed using the means including the catalyst unit 21 and the membrane separation unit 22 and the chemical solution stock solution. A mixing section 52 (manifold) is provided as a pipe.

  A first chemical solution supply pipe 53 that supplies a chemical solution stock solution is connected to the mixing unit 52. A chemical liquid valve 54 and a chemical liquid flow rate adjustment valve 55 are interposed in the first chemical liquid supply pipe 53.

The “chemical solution stock” means a chemical solution before mixing with the inert gas-dissolved water. Examples of chemical stock solutions include hydrofluoric acid (HF), hydrochloric acid (HCL), IPA (isopropyl alcohol), a mixture of hydrofluoric acid and IPA (isopropyl alcohol), and ammonium fluoride (NH ₄ F) it can. When hydrofluoric acid is used as a chemical solution stock solution for the purpose of etching, hydrofluoric acid and hydrogen-dissolved treatment liquid are mixed (prepared) at a predetermined ratio in the mixing unit 52, and dilute hydrofluoric acid (DHF) is mixed. Generated.

By opening the chemical solution valve 54, the chemical solution stock solution having a predetermined flow rate adjusted by the chemical solution flow rate adjusting valve 55 can be supplied to the mixing unit 52. By opening the chemical solution valve 54 with the treatment solution valve 28 opened, the chemical solution stock solution is injected (injected) into the hydrogen-dissolved treatment solution circulating in the mixing section 52, and the chemical solution stock solution, the hydrogen-dissolved treatment solution, Can be mixed.
Therefore, a chemical solution diluted to a predetermined ratio can be prepared by adjusting the supply amount of the chemical solution stock and the supply amount of the hydrogen dissolution treatment liquid to the mixing unit 52.

  Further, by opening only the processing liquid valve 28 without opening the chemical liquid valve 54, only the hydrogen-dissolving processing liquid can be supplied to the mixing unit 52. Thereby, the hydrogen-dissolved treatment liquid can be supplied as it is to the treatment liquid nozzle 4 as a rinse liquid without mixing the chemical solution stock solution with the hydrogen-dissolved treatment liquid.

  The end of the first chemical solution supply pipe 53 is inserted into a chemical solution tank 56 that stores a chemical solution stock solution. The chemical liquid tank 56 is a sealed container, and the internal space of the chemical liquid tank 56 is blocked from the external space. A pump 57 is interposed between the chemical solution valve 54 and the chemical solution tank 56 in the first chemical solution supply pipe 53. Furthermore, it is preferable that a filter and a deaeration unit (not shown) are interposed in the first chemical solution supply pipe 53 on the downstream side of the pump 57. The first chemical liquid supply pipe 53 is divided into two branches downstream of the pump 57: a path toward the chemical liquid valve 54 and the mixing unit 52 and a path toward another processing chamber.

  Further, a second chemical liquid supply pipe 75 is connected to the chemical liquid tank 56. The chemical solution stock 56 is supplied from a chemical solution supply source (not shown) to the chemical solution tank 56 via a chemical solution supply pipe 75. The second chemical solution supply pipe 75 is provided with a chemical solution valve 76 for switching supply and stop of supply of the chemical solution to the chemical solution tank 56. For example, when the amount of liquid in the chemical liquid tank 56 becomes a predetermined amount or less, an unused chemical liquid stock solution is supplied to the chemical liquid tank 56. Thereby, the chemical | medical solution tank 56 can be replenished with an unused chemical | medical solution stock solution.

  Further, an inert gas supply pipe 77 is connected to the chemical tank 56. The chemical liquid tank 56 is supplied with an inert gas from an inert gas supply source (not shown) via an inert gas supply pipe 77. The inert gas supply pipe 77 is provided with an inert gas valve 78 for switching between supply and stop of supply of the inert gas to the chemical tank 56. The chemical liquid tank 56 is always supplied with, for example, an inert gas. In this modification, an inert gas supply means is constituted by the inert gas supply pipe 77 and the inert gas valve 78.

  By supplying an inert gas to the chemical liquid tank 56, air can be expelled from the chemical liquid tank 56. Therefore, it is possible to suppress or prevent the oxygen contained in the air in the chemical liquid tank 56 from being dissolved in the chemical liquid stock stored in the chemical liquid tank 56 and increasing the amount of dissolved oxygen in the chemical liquid stock. It is also possible to pressurize the chemical solution stock stored in the chemical solution tank 56 to the first chemical solution supply pipe 53 by pressurizing the chemical solution tank 56 with an inert gas.

  The chemical solution stock solution in the chemical solution tank 56 is pumped out of the chemical solution tank 56 by the pressure of the inert gas or the suction force by the pump 57 and sent to the first chemical solution supply pipe 53. At this time, if a filter and a deaeration unit are provided immediately downstream of the pump 57, the chemical solution stock pumped by the pump 57 passes through the filter to remove foreign matters in the liquid. Furthermore, the chemical solution stock that has passed through the filter is degassed by the degassing unit, and the amount of dissolved oxygen is reduced. As a result, the chemical stock solution having a reduced dissolved oxygen amount can be supplied to the mixing unit 52, and the effects of the present invention can be further enhanced.

  In addition, you may apply this deformation | transformation aspect 2 to the deformation | transformation aspect 1 shown in FIG. In this case, it is preferable that the chemical solution preparation unit 51 is configured in a pipe portion between the catalyst unit 21 and the membrane separation unit 22 in the modification 1.

<Deformation mode 3>
In the embodiment of FIG. 5 described above, the chemical solution stock solution is injected into the hydrogen-dissolved processing solution flowing in the mixing unit 52 that is a part of the processing solution supply pipe 27, and the chemical solution stock solution and the hydrogen-dissolved processing solution are mixed. However, the present invention can also take the form of FIG. In other words, a hydrogen-dissolving treatment liquid that circulates in the treatment liquid supply pipe 27 and a chemical solution stock solution are introduced into the tank, and the chemical solution stock solution is diluted with the hydrogen-dissolving treatment solution and supplied to the treatment solution nozzle 4. This is effective when a chemical solution that cannot be passed through the catalyst unit 21 is used and when it is difficult to achieve the target dilution rate in the embodiment of FIG. 5 (mixing unit in the pipe).

  Referring to FIG. 6, a chemical liquid preparation unit 81 is added to the processing liquid supply pipe 27 in the aspect shown in FIG.

  The chemical solution preparation unit 81 receives a hydrogen-dissolved treatment solution from which dissolved oxygen and hydrogen peroxide have been removed using a means including the catalyst unit 21 and the membrane separation unit 22 and a chemical solution stock solution, and prepares a diluted chemical solution. A chemical dilution tank 82 is provided. The chemical solution dilution tank 82 is a closed container, and the internal space of the chemical solution dilution tank 82 is blocked from the external space.

  One end of a diluted chemical solution supply pipe 83 for supplying a diluted chemical solution is inserted into the chemical solution dilution tank 82. The other end of the diluted chemical supply pipe 83 is connected to a portion of the processing liquid supply pipe 27 that is downstream from the processing liquid valve 28. The diluted chemical solution supply pipe 83 is provided with a diluted chemical solution valve 84 for switching between supply and stop of supply of the diluted chemical solution to the treatment liquid supply tube 27.

  Further, a pump 57 is interposed between the diluted chemical solution valve 84 and the chemical solution dilution tank 82 in the diluted chemical solution supply pipe 83. It is preferable that a filter and a deaeration unit (not shown) are interposed in the portion of the diluent supply pipe 83 on the downstream side of the pump 57. The diluting chemical liquid supply pipe 83 is branched into two paths downstream of the pump 57: a path toward the diluting chemical liquid valve 84 and a path toward another processing chamber.

  In addition, one end of a second processing liquid supply pipe 85 that supplies a hydrogen-dissolving processing liquid is inserted into the chemical liquid dilution tank 82. The other end of the second processing liquid supply pipe 85 is connected to a portion of the processing liquid supply pipe 27 that is upstream of the processing liquid valve 28. The second treatment liquid supply pipe 85 is supplied with a treatment liquid valve 86 for switching between supply and stop of supply of the hydrogen dissolution treatment liquid to the chemical dilution tank 82 and a hydrogen dissolution treatment liquid supplied to the chemical dilution tank 82. And a processing liquid flow rate adjustment valve 87 for adjusting the flow rate of the liquid.

  A chemical solution supply pipe 75 is connected to the chemical solution dilution tank 82. A chemical stock solution is supplied from a chemical solution supply source (not shown) into the chemical dilution tank 82 through a chemical supply pipe 75. The chemical solution supply pipe 75 includes a chemical solution valve 76 for switching between supply and stop of supply of the chemical solution to the chemical solution dilution tank 82 and a chemical solution flow rate adjustment valve for adjusting the chemical solution stock solution supplied to the chemical solution dilution tank 82 to a predetermined flow rate. 79 is interposed.

  Further, an inert gas supply pipe 77 is connected to the chemical solution dilution tank 82. An inert gas from an inert gas supply source (not shown) is supplied to the chemical solution dilution tank 82 via an inert gas supply pipe 77. The inert gas supply pipe 77 is provided with an inert gas valve 78 for switching between supply and stop of supply of the inert gas to the chemical solution dilution tank 82. The chemical liquid tank 56 is always supplied with, for example, an inert gas. The inert gas supply pipe 77 and the inert gas valve 78 constitute an inert gas supply means.

  In this aspect, by opening another processing liquid valve 86 without opening the processing liquid valve 28, a predetermined flow rate of hydrogen-dissolved processing liquid adjusted by the processing liquid flow rate adjustment valve 87 is supplied to the chemical dilution tank 82. Can do. Further, by opening the chemical solution stock valve 76 without opening the processing solution valve 28, the chemical solution stock solution having a predetermined flow rate adjusted by the chemical solution flow rate adjusting valve 79 can be supplied to the chemical solution dilution tank 82. By these operations, the chemical solution stock solution and the hydrogen dissolution treatment solution can be mixed in the chemical solution dilution tank 82. Therefore, by adjusting the supply amount of the chemical solution stock and the supply amount of the hydrogen-dissolving treatment liquid using the processing liquid flow rate adjustment valve 87 and the chemical flow rate adjustment valve 79, the chemical solution diluted to a predetermined ratio is stored in the chemical solution dilution tank. 82 can be prepared. Then, it is possible to supply the diluted chemical liquid to the processing liquid nozzle 4 by opening only the diluted chemical liquid valve 84 without opening the processing liquid valve 28.

  On the other hand, by opening only the processing liquid valve 28 without opening the diluting chemical liquid valve 84, only the hydrogen-dissolving processing liquid can be supplied to the processing chamber 2. Thereby, the hydrogen-dissolved treatment liquid can be supplied as it is to the treatment liquid nozzle 4 as a rinse liquid without mixing the chemical solution stock solution with the hydrogen-dissolved treatment liquid.

  Further, by supplying an inert gas to the chemical solution dilution tank 82 using the inert gas supply pipe 77, air can be expelled from the chemical solution dilution tank 82. Therefore, it is possible to suppress or prevent the oxygen contained in the air in the chemical solution dilution tank 82 from being dissolved in the diluted chemical solution stored in the chemical solution dilution tank 82 and increasing the amount of dissolved oxygen in the diluted chemical solution. . It is also possible to pressurize the diluted chemical solution in the chemical solution dilution tank 82 to the diluted chemical solution supply pipe 83 by pressurizing the chemical solution dilution tank 82 with an inert gas.

  The diluted chemical solution in the chemical solution dilution tank 82 is pumped out of the chemical solution dilution tank 82 and sent to the diluted chemical solution supply pipe 83 by the pressure of the inert gas or the suction force by the pump 57. At this time, if a filter and a deaeration unit are provided immediately downstream of the pump 57, the diluted chemical liquid pumped out by the pump 57 passes through the filter to remove foreign substances in the liquid. Furthermore, the diluted chemical solution that has passed through the filter is degassed by the degassing unit, and the amount of dissolved oxygen is reduced. As a result, it is possible to supply the treatment liquid supply pipe 27 with a diluted chemical solution with a reduced amount of dissolved oxygen, and the effects of the present invention can be further enhanced.

  In addition, you may apply this deformation | transformation aspect 3 to the deformation | transformation aspect 1 shown in FIG. In this case, it is preferable to arrange the chemical solution preparation unit 81 in the piping portion between the catalyst unit 21 and the membrane separation unit 22 in the modified embodiment 1.

  Furthermore, in this modification 3, the other process liquid supply pipe 90 that supplies another process liquid (for example, process water that does not require hydrogen addition, such as ozone water) to the process liquid nozzle 4 is provided. The processing liquid supply pipe 27 may be connected to the downstream side of the processing liquid valve 28. The processing liquid supply pipe 90 is provided with a processing liquid valve 91 for switching between supply and stop of supply of other processing liquids to the processing liquid nozzle 4. A processing liquid can be selected by switching the opening / closing operations of the processing liquid valve 28, the processing liquid valve 91, and the diluting chemical liquid valve 84 by the control unit 5.

<Deformation aspect 4>
Although the processing liquid nozzles 4 of the various modes described above are held by the nozzle arm 19 and the support shaft 20, the mode shown in FIG. Instead of the treatment liquid nozzle 4 held by the nozzle arm 19 and the support shaft 20, the embodiment of FIG.

  Referring to FIG. 7, the blocking plate 11 is a disk-like member having a substantially constant thickness. The diameter of the blocking plate 11 is larger than that of the substrate W. The blocking plate 11 is disposed horizontally above the spin chuck 3 so that the central axis thereof is located on the same axis as the rotation axis of the spin chuck 3.

  The outer peripheral portion of the blocking plate 11 is bent downward over the entire circumference. The outer peripheral portion of the blocking plate 11 forms a cylindrical peripheral wall portion 32. A portion inside the peripheral wall portion 32 of the blocking plate 11 forms a flat plate portion 33 having a circular shape. The lower surface of the flat plate portion 33 is formed in a plane and is parallel to the upper surface of the substrate W held by the spin chuck 3. The lower surface of the flat plate portion 33 is a substrate facing surface 34 that faces the substrate W held by the spin chuck 3. The substrate facing surface 34 faces the substrate W held by the spin chuck 3 and faces the upper surface of the spin base 8. The peripheral wall portion 32 protrudes from the periphery of the substrate facing surface 34 toward the spin chuck 3.

  A central portion of the blocking plate 11 has a hollow support shaft 31 that supports the blocking plate 11, and a processing liquid supply pipe 27 is inserted into the support shaft 31. One or more discharge ports (not shown) are formed in the blocking plate 11 and communicate with the internal space of the support shaft 31. The processing liquid is supplied to the internal space of the support shaft 31 through the processing liquid supply pipe 27. Thereby, the processing liquid can be discharged from the discharge port formed in the blocking plate 11 toward the upper surface portion of the substrate W held by the spin chuck 3.

  Further, a gas supply pipe 39 is inserted into the support shaft 31. Nitrogen gas, which is an example of an inert gas, is supplied from the gas supply pipe 39 to the internal space of the support shaft 31. The inert gas supplied to the internal space of the support shaft 31 is discharged downward from a discharge port (not shown) formed in the blocking plate 11. For this reason, an inert gas can be supplied to the space (gap) between the shielding plate 11 and the substrate W held by the spin chuck 3.

  The gas supply pipe 39 is provided with a gas valve 41 for switching between supply and stop of supply of the inert gas to the gap, and a gas flow rate adjustment valve 18 for adjusting the supply flow rate of the inert gas to the gap. ing.

  Further, the support shaft 31 is coupled with a shield plate lifting drive mechanism (a shield member moving mechanism) and a shield plate rotation drive mechanism. By the driving force of the blocking plate lifting / lowering drive mechanism, the support shaft 31 and the blocking plate 11 are moved between a processing position where the substrate facing surface 34 approaches the upper surface of the spin base 8 and a retreat position where the substrate facing surface 34 is far away from the upper surface of the spin base 8 Can be moved up and down integrally. Furthermore, the support shaft 31 and the blocking plate 11 can be rotated integrally around the common axis with the substrate W by the driving force of the blocking plate rotation drive mechanism. Thereby, for example, the support shaft 31 and the blocking plate 11 can be rotated almost in synchronization with the rotation of the substrate W by the spin chuck 3 (or at a slightly different rotational speed).

  In the embodiment of FIG. 7, when the blocking plate 11 is positioned at the processing position while the substrate W is held on the spin chuck 3, and the inert gas is discharged from the discharge port positioned on the substrate facing surface 34, The active gas spreads outward in the space between the upper surface of the substrate W held by the spin chuck 3 and the substrate facing surface 34. Therefore, the air existing in the space between the upper surface of the substrate W and the substrate facing surface 34 is pushed outward by the inert gas, and is formed between the tip edge of the peripheral wall portion 32 and the upper surface of the spin base 8. It is discharged from the gap. Thereby, the atmosphere between the upper surface of the substrate W and the substrate facing surface 34 can be replaced with an inert gas.

  Further, when the blocking plate 11 is positioned at the processing position while the substrate W is held on the spin chuck 3, the space between the upper surface of the substrate W and the substrate facing surface 34 can be surrounded by the peripheral wall portion 32. It is possible to suppress or prevent the surrounding air from entering the outer peripheral portion of the space. Thereby, after the atmosphere between the upper surface of the substrate W and the substrate facing surface 34 is replaced with an inert gas atmosphere, air enters the space between the upper surface of the substrate W and the substrate facing surface 34, and An increase in the oxygen concentration in the space can be suppressed or prevented.

<Deformation mode 5>
The various modes described so far are the nozzle mode in which the processing liquid nozzle 4 is disposed above the spin check 3 holding the substrate W, or the blocking plate 11 in which the processing liquid discharge port is formed is the spin check 3. It was either of the shielding board aspects arrange | positioned above. However, the present invention may include both the nozzle mode and the blocking plate mode as shown in FIG.

  Further, the number of the processing liquid nozzles is not limited to one, and may be provided for each purpose of processing such as cleaning and etching, or for each type of processing liquid. For example, as shown in FIG. 8, a processing liquid nozzle 4 a for cleaning the peripheral edge of the substrate W may be installed in the processing chamber 2. A treatment liquid nozzle (not shown) for cleaning the blocking plate 11, particularly the substrate facing surface 34, may be provided. Alternatively, it is possible to adopt a mode in which the processing liquid is supplied to the lower surface of the substrate W through the processing liquid supply pipe 27 into the inside of the spin chuck 3 as the substrate holding mechanism.

  Further, the treatment liquid nozzle may be, for example, a two-fluid nozzle that mixes the treatment liquid supplied into the nozzle and an inert gas to generate droplets of the treatment liquid.

<Deformation mode 6>
FIG. 9 is a view showing a preferred mode of piping used in the substrate processing apparatus 1 according to the present invention.

  The above-described piping from the catalyst unit 21 to the discharge port formed in the processing liquid nozzle 4 or the blocking plate 11, piping from the catalyst unit 21 to the chemical dilution tank 82, and from the chemical dilution tank 82 to the processing liquid nozzle 4 or the blocking plate 11 It is preferable that any or all of the pipes extending to the discharge port are formed in the form shown in FIG. In this description, all the pipes are collectively referred to as “pipe 100”.

  Referring to FIG. 9, the pipe 100 has a double structure, and has an inner pipe 101 through which the processing liquid flows and an outer pipe 102 surrounding the inner pipe 101. The inner pipe 101 is supported inside the outer pipe 102 by a support member (not shown) interposed between the inner pipe 101 and the outer pipe 102. The inner pipe 101 is supported in a non-contact state with respect to the outer pipe 102. A cylindrical space is formed between the inner pipe 101 and the outer pipe 102. The inner pipe 101 is made of, for example, a fluororesin such as PFA or PTFE having excellent chemical resistance and heat resistance. The fluororesin can transmit oxygen. As the outer pipe, for example, a pipe made of PVC or a fluororesin can be used.

  The outer pipe 102 is connected to an inert gas supply pipe 104 provided with an inert gas valve 103 and an exhaust pipe 106 provided with an exhaust valve 105. By opening the inert gas valve 103, an inert gas from an inert gas supply source (not shown) (for example, nitrogen gas) can be supplied to the inside of the outer pipe 102 via the inert gas supply pipe 104. Thereby, it is possible to fill the inert gas between the inner pipe 101 and the outer pipe 102. The inert gas valve 103 and the inert gas supply pipe 104 constitute an inert gas filling means. Further, by opening the exhaust valve 105, gas can be exhausted from between the inner pipe 101 and the outer pipe 102.

  By opening the inert gas valve 103 while the exhaust valve 105 is opened, air can be expelled from between the inner pipe 101 and the outer pipe 102, and the atmosphere in the meantime can be replaced with an inert gas atmosphere. Thereby, the inner side piping 101 can be surrounded by an inert gas. Then, after the atmosphere between the inner pipe 101 and the outer pipe 102 is replaced with an inert gas atmosphere, the inner pipe 101 is surrounded by the inert gas by closing the inert gas valve 103 and the exhaust valve 105. Can be maintained.

  By enclosing the inner pipe 101 with an inert gas, the amount of oxygen that enters the inner pipe 101 through the pipe wall of the inner pipe 101 can be reduced. Thereby, it can suppress or prevent that oxygen melt | dissolves in the process liquid which distribute | circulates the inside of the inner side piping 101, and the oxygen concentration in the said process liquid rises.

[Second Embodiment]
Although the processing chamber 2 of the first embodiment described above has a single wafer cleaning mechanism, the processing chamber included in the present invention is not limited to this, and is a processing chamber having a batch cleaning mechanism. May be.

  FIG. 10 shows an example in which the processing chamber in the mode (modified mode 2) in FIG. 5 is replaced with a processing chamber having a batch type cleaning mechanism. However, this figure is an example, and not only the above-described modification 2 but also each of or all of the above-described other modifications 1 to 6 are applied to the processing chamber 2 equipped with the batch-type cleaning mechanism. I can do it. In addition, the same code | symbol is attached | subjected to the same component as 1st embodiment, and since it is the same as 1st embodiment, the description of the component is omitted.

  Referring to FIG. 10, the processing chamber 2 of the substrate processing apparatus 1 according to the second embodiment has a processing tank 201 for storing a processing solution and cleaning the substrate W with the processing solution. On the outer periphery of the processing tank 201, an overflow unit 202 that receives the processing liquid overflowing from the processing tank 201 is provided.

  In the processing chamber 2, a substrate transport mechanism (not shown) for transporting the substrate W into the processing tank 201 is also provided. A lifter and a chuck are used as the substrate transport mechanism. The chuck conveys a plurality of substrates W from outside the processing chamber 2 to above the processing bath 201 in a state where the plurality of substrates W are collectively held. The lifter receives a plurality of substrates W from the chuck above the processing tank 201, descends in a state where the plurality of substrates W are collectively supported, and is immersed in the processing liquid stored in the processing tank 201. To do.

  A processing liquid nozzle 203 for supplying a processing liquid into the processing tank 201 is disposed at the bottom of the processing tank 201. A pipe branched from the treatment liquid supply pipe 27 is connected to each treatment liquid nozzle 203. Each treatment liquid nozzle 203 is formed with a large number of ejection openings for ejecting the treatment liquid toward the substrate W.

  As described in the first embodiment, the treatment liquid is a hydrogen-dissolved treatment liquid from which dissolved oxygen and hydrogen peroxide have been removed using means including the catalyst unit 21 and the membrane separation unit 22.

  The ejected processing liquid is stored in the processing tank 201 and overflows from the upper end of the processing tank 201. The substrate W is uniformly washed by the upward flow of the processing liquid at this time.

  The processing liquid that has been used for the cleaning process of the substrate W and has overflowed from the upper end of the processing tank 201 is temporarily stored in an overflow unit 202 formed on the outer periphery of the processing tank 201. A drain pipe 206 having a resistivity meter 205 is connected to the bottom of the overflow part 202. For this reason, the pure water temporarily stored in the overflow unit 202 passes through the specific resistance meter 205 and is then discharged out of the substrate processing apparatus 1.

  The specific resistance meter 205 measures the cleanliness of the processing liquid by measuring the specific resistance value of the processing liquid used for cleaning the substrate W, and determines the cleaning degree of the substrate W based on the measured value. Used for purposes.

  Further, in order to quickly discharge the processing liquid stored in the processing tank 201, a discharge port 204 having a relatively large diameter is formed at the bottom of the processing tank 201. A drain pipe 207 for discharging the processing liquid to the outside of the substrate processing apparatus 1 is connected to the discharge port 204. A drain valve 208 that is opened and closed by the control unit 5 is interposed in the drain pipe 207.

  A pair of lid members 209 that operate to open and close the opening of the processing tank 201 are disposed above the processing tank 201. Each lid member 209 has a discharge opening, and a pipe branched from the gas supply pipe 39 is connected to the discharge opening. Thereby, the inert gas can be supplied into the processing tank 201 covered with the lid member 209, and the space above the processing liquid in the processing tank 201 can be purged with the inert gas.

  As described above, the inert gas discharge port is formed in the lid member 209 without providing the nozzle for supplying the inert gas in the treatment tank 201, so that the space in the vertical direction composed of the processing tank 201 and the lid member 209 is formed. It is possible to prevent the substrate processing apparatus 1 from becoming large. Further, since the distance between the liquid level of the processing liquid stored in the processing tank 201 and the lower surface of the lid member 209 can be reduced, the amount of inert gas supplied into the processing tank 201 can be reduced. Is possible.

[Third embodiment]
A specific example of the catalyst for removing dissolved oxygen and removing hydrogen peroxide used in the catalyst unit 21 of the substrate processing apparatus 1 described above will be described in detail.

<Catalyst for removing dissolved oxygen and hydrogen peroxide>
The catalyst includes a granular ion exchange resin carrying a platinum group metal, a metal ion type granular cation exchange resin, a non-particulate organic porous material carrying a platinum group metal or a platinum group metal. Non-particulate organic porous ion exchangers.

<Platinum group metal-supported non-particulate organic porous body, platinum group metal-supported non-particulate organic porous ion exchanger>
As the platinum group metal-supported non-particulate organic porous body, fine particles of platinum group metal having an average particle diameter of 1 to 1000 nm are supported on the non-particulate organic porous body, and the non-particulate organic porous body is a continuous skeleton phase. The continuous skeleton has a thickness of 1 to 100 μm, the average diameter of the continuous pores is 1 to 1000 μm, the total pore volume is 0.5 to 50 ml / g, and the supported amount of platinum group metal is A platinum group metal-supported non-particulate organic porous material that is 0.004 to 20% by weight in a dry state.

  Further, as the platinum group metal-supported non-particulate organic porous ion exchanger, fine particles of platinum group metal having an average particle diameter of 1 to 1000 nm are supported on the non-particulate organic porous ion exchanger. The ion exchanger is composed of a continuous skeleton phase and a continuous pore phase, the thickness of the continuous skeleton is 1 to 100 μm, the average diameter of the continuous pores is 1 to 1000 μm, and the total pore volume is 0.5 to 50 ml / g. The ion exchange capacity per weight in the dry state is 1 to 6 mg equivalent / g, the ion exchange groups are uniformly distributed in the organic porous ion exchanger, and the supported amount of the platinum group metal is in the dry state. And a platinum group metal-supported non-particulate organic porous ion exchanger of 0.004 to 20% by weight.

  In addition, the average diameter of the opening of a non-particulate organic porous body or a non-particulate organic porous ion exchanger is measured by the mercury intrusion method, and indicates the maximum value of the pore distribution curve obtained by the mercury intrusion method. Further, the structure of the non-particulate organic porous body or the non-particulate organic porous ion exchanger and the thickness of the continuous skeleton are determined by SEM observation. The particle diameter of the platinum group metal nanoparticles supported on the non-granular organic porous material or the non-granular organic porous ion exchanger is determined by TEM observation.

The platinum group metal-supported non-particulate organic porous material or the platinum group metal-supported non-particulate organic porous ion exchanger has a mean particle diameter of 1 to 100 nm. since the platinum group metal is supported, it shows a high hydrogen peroxide decomposition catalytic activity, and, 200～20000H ^-1 preferably be passed through the treated water at a space velocity (SV) of 2000～20000H ^-1 Can do.

  In the platinum group metal-supported non-particulate organic porous body, the carrier on which the platinum group metal is supported is a non-particulate organic porous body. This non-particulate organic porous exchanger is a monolithic organic porous exchange. Is the body. In the platinum group metal-supported non-particulate organic porous ion exchanger, the carrier on which the platinum group metal is supported is a non-particulate organic porous ion exchanger. A monolithic organic porous ion exchanger, in which an ion exchange group is introduced into the monolithic organic porous body.

  The monolithic organic porous body is a porous body having a skeleton formed of an organic polymer and a large number of communication holes serving as a flow path for a reaction solution between the skeletons. The monolithic organic porous ion exchanger is a porous body introduced so that ion exchange groups are uniformly distributed in the skeleton of the monolithic organic porous body. In the present specification, “monolithic organic porous material” is also simply referred to as “monolith”, and “monolithic organic porous ion exchanger” is also simply referred to as “monolith ion exchanger”, The “monolithic organic porous intermediate” that is the body (precursor) is also simply referred to as “monolith intermediate”.

  Examples of the structure of such a monolith or monolith ion exchanger are disclosed in Japanese Patent Application Laid-Open No. 2002-306976 and Japanese Patent Application Laid-Open No. 2009-62512, and Japanese Patent Application Laid-Open No. 2009-67982. A co-continuous structure, a particle aggregation type structure disclosed in JP 2009-7550 A, a particle composite type structure disclosed in JP 2009-108294 A, and the like.

  Examples of monoliths serving as carriers for the above monolith, that is, platinum group metal particles (hereinafter also referred to as monolith (1)) and monolith ion exchangers, that is, monolith ion exchangers serving as the carrier for platinum group metal particles Examples of the form (hereinafter also referred to as monolith ion exchanger (1)) include monoliths and monolith ion exchangers having a co-continuous structure disclosed in JP-A No. 2009-67982.

  That is, the monolith (1) is a monolith before the ion exchange group is introduced, and has an average thickness composed of an aromatic vinyl polymer containing 0.1 to 5.0 mol% of a crosslinked structural unit among all the structural units. Is a co-continuous structure comprising a three-dimensionally continuous skeleton of 1 to 100 μm in a dry state and three-dimensionally continuous pores having an average diameter of 1 to 1000 μm in a dry state between the skeletons, It is a monolith that is an organic porous body having a total pore volume of 0.5 to 50 ml / g in a dry state.

  In addition, the monolith ion exchanger (1) has a three-dimensional average thickness of 1 to 100 μm in a dry state of an aromatic vinyl polymer containing 0.1 to 5.0 mol% of a crosslinked structural unit among all the structural units. A co-continuous structure composed of a continuous skeleton and three-dimensionally continuous pores having an average diameter of 1 to 1000 μm in a dry state between the skeletons, and the total pore volume in the dry state is 0 5 to 50 ml / g, having an ion exchange group, an ion exchange capacity per weight in a dry state of 1 to 6 mg equivalent / g, and the ion exchange group in the organic porous ion exchanger It is a monolith ion exchanger that is a monolith ion exchanger that is uniformly distributed.

  The monolith (1) or the monolith ion exchanger (1) has a three-dimensional continuous skeleton having an average thickness of 1 to 100 μm, preferably 3 to 58 μm in a dry state, and an average diameter between the skeletons in a dry state. A co-continuous structure composed of three-dimensionally continuous pores of 1 to 1000 μm, preferably 15 to 180 μm, particularly preferably 20 to 150 μm. The co-continuous structure is a structure in which a continuous skeleton phase and a continuous vacancy phase are intertwined, and both are three-dimensionally continuous. The continuous pores have higher continuity of the pores than the conventional open-cell type monolith and the particle aggregation type monolith, and the size thereof is not biased. Moreover, since the skeleton is thick, the mechanical strength is high.

  If the average diameter of the three-dimensionally continuous pores is less than 1 μm in the dry state, it is not preferable because the pressure loss at the time of passing the liquid increases, and if it exceeds 1000 μm, the reaction solution and the monolith or monolith ion exchanger As a result, the contact with the catalyst becomes insufficient, resulting in insufficient catalytic activity. Moreover, when the average thickness of the skeleton is less than 1 μm in a dry state, the monolith or the monolith ion exchanger is greatly deformed when the liquid is passed at a high flow rate. Furthermore, the contact efficiency between the reaction liquid and the monolith or monolith ion exchanger is lowered, and the catalytic effect is lowered, which is not preferable. On the other hand, if the thickness of the skeleton exceeds 100 μm, the skeleton becomes too thick, and the pressure loss during liquid passage increases, which is not preferable.

  The average diameter of the opening of the monolith (1) in the dry state, the average diameter of the opening of the monolith ion exchanger (1) and the opening of the monolith intermediate (1) in the dry state obtained by the I treatment in the production of the monolith described below The average diameter is measured by the mercury intrusion method and refers to the maximum value of the pore distribution curve obtained by the mercury intrusion method. The average thickness of the skeleton of the monolith (1) or the monolith ion exchanger (1) in the dry state is determined by SEM observation of the dry monolith (1) or the monolith ion exchanger (1). Specifically, the SEM observation of the dried monolith (1) or monolith ion exchanger (1) is performed at least three times, the thickness of the skeleton in the obtained image is measured, and the average value thereof is calculated as the average thickness. Say it. The skeleton has a rod-like shape and a circular cross-sectional shape, but may have a cross-section with a different diameter such as an elliptical cross-sectional shape. The thickness in this case is the average of the minor axis and the major axis.

  Moreover, the total pore volume per weight in the dry state of the monolith (1) or the monolith ion exchanger (1) is 0.5 to 50 ml / g. If the total pore volume is less than 0.5 ml / g, the pressure loss at the time of liquid passing is increased, which is not preferable. Further, the permeation amount per unit cross-sectional area is decreased, and the processing amount is decreased. Therefore, it is not preferable. On the other hand, if the total pore volume exceeds 50 ml / g, the mechanical strength is lowered, and the monolith or the monolith ion exchanger is greatly deformed particularly when the liquid is passed at a high flow rate. Furthermore, since the contact efficiency between the reaction liquid and the monolith (1) or the monolith ion exchanger (1) is lowered, the catalyst efficiency is also lowered, which is not preferable. If the three-dimensionally continuous pore size and total pore volume are within the above ranges, the contact with the reaction solution is extremely uniform, the contact area is large, and the solution can be passed under a low pressure loss. .

  In the monolith (1) or the monolith ion exchanger (1), the material constituting the skeleton is 0.1 to 5 mol%, preferably 0.5 to 3.0 mol% of a crosslinked structural unit in all the structural units. It is an aromatic vinyl polymer containing and is hydrophobic. If the cross-linking structural unit is less than 0.1 mol%, the mechanical strength is insufficient, which is not preferable. On the other hand, if it exceeds 5 mol%, the structure of the porous body tends to deviate from the bicontinuous structure. There is no restriction | limiting in particular in the kind of aromatic vinyl polymer, For example, a polystyrene, poly ((alpha) -methylstyrene), polyvinyl toluene, polyvinyl benzyl chloride, polyvinyl biphenyl, polyvinyl naphthalene etc. are mentioned. The polymer may be a polymer obtained by copolymerizing a single vinyl monomer and a crosslinking agent, a polymer obtained by polymerizing a plurality of vinyl monomers and a crosslinking agent, or a blend of two or more types of polymers. It may be what was done. Among these organic polymer materials, styrene-divinylbenzene copolymer has the advantage of easy co-continuous structure formation, ease of ion exchange group introduction and high mechanical strength, and high stability to acids or alkalis. A polymer or vinylbenzyl chloride-divinylbenzene copolymer is preferred.

  In the monolith ion exchanger (1), the introduced ion exchange groups are uniformly distributed not only on the surface of the monolith but also inside the skeleton of the monolith. Here, “ion exchange groups are uniformly distributed” means that the distribution of ion exchange groups is uniformly distributed on the surface and inside the skeleton in the order of at least μm. The distribution status of the ion exchange groups can be easily confirmed by using EPMA. In addition, if the ion exchange groups are uniformly distributed not only on the surface of the monolith but also within the skeleton of the monolith, the physical and chemical properties of the surface and the interior can be made uniform, so that they are resistant to swelling and shrinkage. Improves.

  The ion exchange group introduced into the monolith ion exchanger (1) is a cation exchange group or an anion exchange group. Examples of the cation exchange group include a carboxylic acid group, an iminodiacetic acid group, a sulfonic acid group, a phosphoric acid group, and a phosphoric ester group. Examples of anion exchange groups include trimethylammonium group, triethylammonium group, tributylammonium group, dimethylhydroxyethylammonium group, dimethylhydroxypropylammonium group, methyldihydroxyethylammonium group, quaternary ammonium group, tertiary sulfonium group, phosphonium group. Etc.

  The monolith ion exchanger (1) has an ion exchange capacity of 1 to 6 mg equivalent / g of ion exchange capacity per weight in a dry state. Since the monolith ion exchanger (1) has high continuity and uniformity of three-dimensionally continuous pores, the pressure loss does not increase so much even if the total pore volume is reduced. Therefore, it is possible to dramatically increase the ion exchange capacity per volume while keeping the pressure loss low. When the ion exchange capacity per weight is in the above range, the environment around the catalyst active point such as the pH inside the catalyst can be changed, and thereby the catalyst activity is increased. When the monolith ion exchanger (1) is a monolith anion exchanger, an anion exchange group is introduced into the monolith anion exchanger (1), and the anion exchange capacity per weight in the dry state is 1 to 6 mg. Equivalent / g. When the monolith ion exchanger (1) is a monolith cation exchanger, a cation exchange group is introduced into the monolith cation exchanger (1), and the cation exchange capacity per weight in a dry state is 1 ~ 6 mg equivalent / g.

  The monolith (1) can be obtained by carrying out the method for producing a monolithic organic porous material disclosed in Japanese Patent Application Laid-Open No. 2009-66792. That is, the production method prepares a water-in-oil emulsion by stirring a mixture of an oil-soluble monomer that does not contain an ion-exchange group, a surfactant, and water, and then polymerizes the water-in-oil emulsion to form all pores. I treatment for obtaining a monolithic organic porous intermediate (hereinafter also referred to as monolith intermediate (1)) having a continuous macropore structure having a volume of more than 16 ml / g and 30 ml / g or less, an aromatic vinyl monomer, one In all oil-soluble monomers having at least two vinyl groups in the molecule, 0.3 to 5 mol% of the crosslinking agent, aromatic vinyl monomer and crosslinking agent are dissolved, but the aromatic vinyl monomer is polymerized to form. Preparation of a mixture comprising an organic solvent in which the polymer does not dissolve and a polymerization initiator II treatment, a monolith intermediate obtained by standing the mixture obtained by the II treatment and by the I treatment Polymerization was conducted in the presence of 1), including III treatment, to obtain a monolith (1) is an organic porous material is a co-continuous structure.

  A platinum group metal is supported on the platinum group metal-supported non-particulate organic porous body or the platinum group metal-supported non-particulate organic porous ion exchanger. The platinum group metal is ruthenium, rhodium, palladium, osmium, iridium, or platinum. These platinum group metals may be used alone or in combination of two or more metals, and more than one metal may be used as an alloy. Among these, platinum, palladium, and platinum / palladium alloys have high catalytic activity and are preferably used.

  The average particle diameter of the platinum group metal particles supported on the platinum group metal-supported non-particulate organic porous material or platinum group metal-supported non-particulate organic porous ion exchanger is 1-1000 nm, preferably 1-200 nm, More preferably, it is 1-20 nm. If the average particle diameter is less than 1 nm, the possibility that the platinum group metal particles will be detached from the carrier increases, which is not preferable. On the other hand, if the average particle diameter exceeds 1000 nm, the surface area per unit mass of the metal decreases. This is not preferable because the catalytic effect cannot be obtained efficiently. In addition, the average particle diameter of a platinum group metal particle is calculated | required by image-analyzing the TEM image obtained by a transmission electron microscope (TEM) analysis.

  Platinum group metal-supported non-particulate organic porous material or platinum group metal-supported non-particulate organic porous ion exchanger supported amount of platinum group metal particles ((platinum group metal particles / platinum group metal-supported catalyst in dry state) × 100 ) Is 0.004 to 20% by weight, preferably 0.005 to 15% by weight. If the supported amount of platinum group metal particles is less than 0.004% by weight, the catalytic activity becomes insufficient, such being undesirable. On the other hand, when the amount of platinum group metal particles is more than 20% by weight, metal elution into water is observed, which is not preferable.

  There are no particular restrictions on the method for producing the platinum group metal-supported non-particulate organic porous material or the platinum group metal-supported non-particulate organic porous ion exchanger. A platinum group metal-supported catalyst can be obtained by supporting fine particles of a platinum group metal on a monolith or a monolith ion exchanger by a known method. Examples of the method for supporting the platinum group metal on the non-particulate organic porous body or the non-particulate organic porous ion exchanger include the method disclosed in JP 2010-240641 A. For example, a dried monolith ion exchanger is immersed in a methanol solution of a platinum group metal compound such as palladium acetate, and palladium ions are adsorbed on the monolith ion exchanger by ion exchange, and then contacted with a reducing agent to form palladium metal fine particles. And the monolith ion exchanger is immersed in an aqueous solution of a platinum group metal compound such as a tetraammine palladium complex, and the palladium ions are adsorbed on the monolith ion exchanger by ion exchange, and then the reducing agent and In this method, palladium metal fine particles are supported on a monolith ion exchanger by contact.

  The granular ion exchange resin carrying a platinum group metal is one in which a platinum group metal is carried on a granular ion exchange resin. The particulate ion exchange resin that serves as the platinum group metal carrier is not particularly limited, and examples thereof include strongly basic anion exchange resins. Then, the granular ion exchange resin is loaded with a platinum group metal by a known method to obtain a granular ion exchange resin loaded with the platinum group metal.

  The metal ion type granular cation exchange resin on which a metal is supported is obtained by supporting a metal such as iron ion, copper ion, nickel ion, chromium ion or cobalt ion on a granular cation exchange resin. The granular cation exchange resin to be a carrier is not particularly limited, and examples thereof include strongly acidic cation exchange resins. And metal, such as an iron ion, copper ion, nickel ion, chromium ion, and cobalt ion, is carry | supported by a granular cation exchange resin by a well-known method, and a metal ion type granular cation exchange resin is obtained.

  Hereinafter, the catalyst of the catalyst unit 21 used in the present invention will be described more specifically, but this is merely an example and does not limit the present invention.

<Production of platinum group metal-supported non-particulate organic porous ion exchanger>
(Production of monolith intermediate (I treatment))
9.28 g of styrene, 0.19 g of divinylbenzene, 0.50 g of sorbitan monooleate (hereinafter abbreviated as SMO) and 0.25 g of 2,2′-azobis (isobutyronitrile) were mixed and dissolved uniformly. Next, the styrene / divinylbenzene / SMO / 2,2′-azobis (isobutyronitrile) mixture was added to 180 g of pure water, and a vacuum stirring defoaming mixer (manufactured by EM Co.) as a planetary stirring device. Was stirred under reduced pressure to obtain a water-in-oil emulsion. This emulsion was quickly transferred to a reaction vessel and allowed to polymerize at 60 ° C. for 24 hours in a static state after sealing. After completion of the polymerization, the content was taken out, extracted with methanol, and then dried under reduced pressure to produce a monolith intermediate having a continuous macropore structure. The internal structure of the monolith intermediate (dry body) thus obtained was observed by SEM. From the SEM image, although the wall section that divides two adjacent macropores is very thin and rod-shaped, it has an open cell structure, and the average of the openings (mesopores) where the macropores and macropores overlap measured by the mercury intrusion method The diameter was 40 μm and the total pore volume was 18.2 ml / g.

(Manufacture of monoliths)
Subsequently, 216.6 g of styrene, 4.4 g of divinylbenzene, 220 g of 1-decanol, and 0.8 g of 2,2′-azobis (2,4-dimethylvaleronitrile) were mixed and dissolved uniformly (II treatment). Next, the above monolith intermediate is placed in a reaction vessel, immersed in the styrene / divinylbenzene / 1-decanol / 2,2′-azobis (2,4-dimethylvaleronitrile) mixture, and degassed in a vacuum chamber. The reaction vessel was sealed and allowed to polymerize at 50 ° C. for 24 hours. After completion of the polymerization, the content was taken out, subjected to Soxhlet extraction with acetone, and then dried under reduced pressure (III treatment).

  The internal structure of the monolith (dry body) containing 1.2 mol% of the crosslinking component composed of the styrene / divinylbenzene copolymer thus obtained was observed by SEM. From the SEM observation, the monolith has a co-continuous structure in which the skeleton and the vacancies are three-dimensionally continuous, and both phases are intertwined. Moreover, the average thickness of the skeleton measured from the SEM image was 20 μm. Further, the average diameter of the three-dimensionally continuous pores of the monolith measured by mercury porosimetry was 70 μm, and the total pore volume was 4.4 ml / g. The average diameter of the pores was determined from the maximum value of the pore distribution curve obtained by the mercury intrusion method.

(Production of monolith anion exchanger)
The monolith produced by the above method is put into a column reactor, and a solution consisting of 1600 g of chlorosulfonic acid, 400 g of tin tetrachloride and 2500 ml of dimethoxymethane is circulated and passed through, and reacted at 30 ° C. for 5 hours to give a chloromethyl group. Was introduced. After completion of the reaction, the chloromethylated monolith was washed with a mixed solvent of THF / water = 2/1, and further washed with THF. To this chloromethylated monolith, 1600 ml of THF and 1400 ml of 30% aqueous solution of trimethylamine were added and reacted at 60 ° C. for 6 hours. After completion of the reaction, the product was washed with methanol and then with pure water to obtain a monolith anion exchanger.

  The obtained monolith anion exchanger had an anion exchange capacity of 4.2 mg equivalent / g in a dry state, and it was confirmed that quaternary ammonium groups were quantitatively introduced. Further, the thickness of the skeleton in the dry state measured from the SEM image is 20 μm, and the average diameter in the dry state of the three-dimensional continuous pores of the monolith anion exchanger determined from the measurement by the mercury intrusion method. Was 70 μm and the total pore volume in the dry state was 4.4 ml / g.

  Next, in order to confirm the distribution state of the quaternary ammonium group in the monolith anion exchanger, the monolith anion exchanger was treated with an aqueous hydrochloric acid solution to form a chloride form, and then the distribution state of chloride ions was observed by EPMA. . As a result, it was confirmed that the chloride ions were uniformly distributed not only on the skeleton surface of the monolith anion exchanger but also inside the skeleton, and the quaternary ammonium groups were uniformly introduced into the monolith anion exchanger. It was.

(Supporting platinum group metals)
The monolith anion exchanger was ion-exchanged into Cl form, cut into a cylindrical shape in a dry state, and dried under reduced pressure. The weight of the monolith anion exchanger after drying was 1.2 g. This dried monolith anion exchanger was immersed in dilute hydrochloric acid in which 100 mg of palladium chloride was dissolved for 24 hours, and ion-exchanged to the palladium chloride acid form. After completion of the immersion, the monolith anion exchanger was washed several times with pure water, and immersed in an aqueous hydrazine solution for 24 hours for reduction treatment. The chloropalladium acid form monolith anion exchanger was brown, whereas the monolith anion exchanger after the reduction treatment was colored black, suggesting the formation of palladium fine particles. The sample after the reduction was washed several times with pure water and then dried by pressure detection drying.

  When the amount of palladium supported was determined by ICP emission spectroscopy, the amount of palladium supported was 3.9% by weight. In order to confirm the distribution state of palladium supported on the monolith cation exchanger, the distribution state of palladium was observed by EPMA. It was confirmed that palladium was distributed not only on the surface of the skeleton of the monolith anion exchanger but also inside the skeleton, and it was relatively uniformly distributed inside, although the concentration was slightly higher. In order to measure the average particle diameter of the supported palladium particles, observation with a transmission electron microscope (TEM) was performed. The average particle diameter of the palladium fine particles was 8 nm.

  Below, the measurement result obtained by processing the board | substrate W with the substrate processing apparatus 1 is demonstrated.

[Substrate to be processed (sample)]
A test wafer in which molybdenum was formed into a thickness of 200 nm on a 4-inch silicon wafer by sputtering was used. In recent years, molybdenum has been used on a substrate as a refractory metal for a gate electrode of a MOS type element, and corrosion of molybdenum was evaluated.

[Evaluation method]
The sheet resistance before and after the cleaning treatment was measured using a 4-terminal probe type sheet resistance measuring instrument, and the difference was recorded. As the metal elutes and the film thickness decreases, the sheet resistance increases.

[Substrate processing equipment (cleaning equipment)]
As the substrate processing apparatus, a batch type cleaning apparatus manufactured by Organo Corporation was used. As the inert gas, 99.999% nitrogen gas was used, and the processing time of the test wafer in the processing tank was 120 minutes.

[Raw water (ultra pure water)]
As for ultrapure water, secondary pure water of an ultrapure water production apparatus installed in Organo Corporation Development Center was used. The water quality at the outlet of the ultrapure water production apparatus is as shown in Table 1 below. The outlet of the ultrapure water production apparatus and the inlet of the substrate processing apparatus (cleaning apparatus) were connected by a pipe of about 50 m, and the dissolved oxygen concentration at the cleaning apparatus inlet was 8 μg / L.

[Evaluated treated water]
The hydrogen peroxide-removed water was obtained by passing the above ultrapure water through a palladium-supported monolith. At this time, the hydrogen peroxide concentration was 2 μg / L or less.

  Hydrogen water was obtained by adding hydrogen to the above ultrapure water through a hollow fiber membrane. The hydrogen concentration was measured with a dissolved hydrogen meter DHDI-1 manufactured by Toa DK Corporation. The hydrogen concentration was controlled by a mass flow controller for the amount of hydrogen gas supplied to the hollow fiber membrane.

  The water from which oxygen and hydrogen peroxide were removed was obtained by passing the hydrogen water through a palladium-supported monolith. The dissolved oxygen concentration was measured using a model 410 made by Orbis Fair.

[Reference Example 1]
The test wafer was immersed in the ultrapure water for 24 hours, and then the hydrogen peroxide concentration in the treated water was measured. The results are shown in Table 2 below. It has been found that molybdenum produces hydrogen peroxide when in contact with oxygen.

[Example 1]
The test wafer was processed in a state where the oxygen gas concentration in the cleaning chamber of the batch cleaning apparatus was 2% or less. The results (increase in sheet resistance) are shown in Table 3 below.

   From the evaluation results of Table 3, it was found that corrosion of molybdenum can be suppressed by removing hydrogen peroxide from the above ultrapure water. The sheet resistance increment at this time is almost the same as in the case of the hydrogen water. Furthermore, when water obtained by adding hydrogen to hydrogen peroxide-removed water at a predetermined concentration or more is used for processing a substrate in a low oxygen atmosphere, the sheet resistance can be made below the detection limit.

  From the evaluation results, it is preferable that the treated water of molybdenum has at least a hydrogen peroxide concentration of 2 μg / L or less, a dissolved oxygen concentration of 2 μg / L or less, a hydrogen peroxide concentration of 2 μg / L or less, It can be seen from Table 3 that the most effective results are obtained when the dissolved hydrogen concentration is adjusted to exceed 10 μg / L, preferably 50 μg / L or more.

[Example 2]
The oxygen gas concentration in the cleaning chamber of the batch type cleaning apparatus was adjusted, and water from which oxygen and hydrogen peroxide had been removed was used. Under the adjusted oxygen gas concentration, the test wafer was processed. 4 shows.

   When the oxygen gas concentration in the treatment chamber for performing the treatment of Example 2 was set to 0.1% or less, corrosion of molybdenum could be completely suppressed.

  From this evaluation result, the following can be understood. A treatment that removes oxygen and hydrogen peroxide from the above ultrapure water, and uses the treated water obtained by adding hydrogen to the ultrapure water from which oxygen and hydrogen peroxide have been removed, and then performs substrate treatment with the treated water. It was found that elution of molybdenum exposed on the substrate surface can be completely suppressed when the oxygen gas concentration in the room is 2% or less.

Therefore, it can be said that providing the catalyst unit 21 and the separation membrane unit 22 as in the substrate processing apparatus 1 of the various aspects described above has an effect of completely suppressing the elution of molybdenum.
[Example 3]
Prepare the above sample (molybdenum exposed substrate) as a test wafer, adjust the gas component in the cleaning chamber of the batch type cleaning device, and use water from which hydrogen peroxide has been removed. Table 5 below shows the results of measuring the contact angle of the substrate surface after processing the test wafer.

   From this evaluation result, the following can be understood. A substrate treated with ultrapure water from which hydrogen peroxide has been removed has a larger contact angle than a substrate treated with ultrapure water containing hydrogen peroxide. That is, the surface becomes more hydrophobic. This is considered to be an effect in which oxidation of the substrate surface by hydrogen peroxide is suppressed. Further, a substrate treated in a nitrogen atmosphere has a larger contact angle than a substrate treated in an air atmosphere. That is, the surface becomes more hydrophobic. This is considered to be an effect in which oxidation of the substrate surface by oxygen contained in the air is suppressed.

It can be said that the removal of hydrogen peroxide from ultrapure water and / or the treatment in an atmosphere with a reduced oxygen concentration has an effect of suppressing an unexpected oxidation reaction of the molybdenum-exposed substrate.
[Reference example]
An n-type silicon wafer was prepared as a test wafer, and the contact angle was measured by changing the condition of the treated water from that in Example 3 above. That is, the gas component in the cleaning chamber of the batch type cleaning apparatus was adjusted, and the test was performed using water from which hydrogen peroxide had been removed and water to which 50 μg / L of hydrogen peroxide had been added, in a gas atmosphere in which the component was adjusted. The results of measuring the contact angle on the substrate surface after processing the wafer are shown in Table 6 below.

   From this evaluation result, the following can be understood. A substrate treated with ultrapure water from which hydrogen peroxide has been removed has a larger contact angle than a substrate treated with ultrapure water containing hydrogen peroxide. That is, the surface becomes more hydrophobic. This is considered to be an effect in which oxidation of the substrate surface by hydrogen peroxide is suppressed. Further, a substrate treated in a nitrogen atmosphere has a larger contact angle than a substrate treated in an air atmosphere. That is, the surface becomes more hydrophobic. This is considered to be an effect in which oxidation of the substrate surface by oxygen contained in the air is suppressed.

  It can be seen that the removal of hydrogen peroxide from ultrapure water and / or treatment in an atmosphere with a reduced oxygen concentration affects the wettability of the silicon substrate, that is, the oxidation state.

W ... Substrate 1 ... Substrate processing apparatus 1a ... Processing liquid inlet 2 of substrate processing apparatus 1 ... Processing chamber 3 ... Spin chuck 4 ... Processing liquid nozzle 5 ... Control unit 6 ··· Holding member 7 ··· Chuck rotation drive mechanism 8 ··· Spin base 9 ··· Subsystem 9a of ultrapure water production apparatus · · · Treatment liquid outlet of subsystem 9 10 · Main piping 10a · ··· Branch 11 ··· Shut-off plate 18 ··· Gas flow rate adjusting valve 19 ··· Nozzle arm 20 ··· Support shaft 21 ··· Catalyst unit 22 ··· Membrane separation unit 23 · · · drainage pipe ... Drain valve 27 ... Processing liquid supply pipe 28 ... Processing liquid valve 31 ... Support shaft 32 ... Surrounding wall part 33 ... Plate part 34 ... Substrate facing surface 39 ... Gas Supply pipe 41 ... Gas valve 51 ... Chemical solution preparation unit 52 ... Mixing unit 53 ... First chemical liquid supply pipe 54 ... Chemical liquid valve 55 ... Chemical liquid flow rate adjusting valve 56 ... Chemical liquid tank 57 ... Pump 75 ... Second Chemical solution supply pipe 76 ... Chemical solution valve 77 ... Inert gas supply tube 78 ... Inert gas valve 81 ... Chemical solution preparation unit 82 ... Chemical solution dilution tank 83 ... Diluted chemical solution supply tube 84 ... Diluted chemical liquid valve 85 ... second processing liquid supply pipe 86 ... processing liquid valve 87 ... processing liquid flow rate adjustment valve 90 ... processing liquid supply pipe 91 ... processing liquid valve 100 ... Piping 101 ... Inner piping 102 ... Outer piping 103 ... Inert gas valve 104 ... Inert gas supply pipe 105 ... Exhaust valve 201 ... Processing tank 202 ... Overflow unit 203 ...・ Processing liquid nozzle 04 ... outlet 205 ... resistivity meter 206, 207 ... water discharge pipe 208 ... drain valve 209 ... lid member

Claims (3)

Placing a substrate having at least molybdenum or a molybdenum compound exposed on its surface in a processing chamber ;
Producing a treatment liquid in which the hydrogen peroxide concentration dissolved in the liquid is 2 μg / L or less and the dissolved oxygen concentration is adjusted to 2 μg / L or less ;
Treating the substrate in the processing chamber with the processing liquid ,
The step of generating the treatment liquid is a monolithic organic porous anion formed on a treatment liquid supply pipe branched from a main pipe connected to a subsystem of an ultrapure water production apparatus and connected to the treatment chamber. A platinum group metal catalyst that is supported on the exchanger is installed, and hydrogen-dissolved water obtained by adding hydrogen to the ultrapure water from the ultrapure water production apparatus is passed through the platinum group metal catalyst. And a method for treating a molybdenum-exposed substrate, comprising generating a hydrogen-dissolving treatment liquid as the treatment liquid . The dissolved hydrogen concentration in the treated solution Ru der than 10 [mu] g / L, the processing method of molybdenum exposed substrate according to claim 1. Step that processes the pre-Symbol substrate, in an atmosphere of oxygen gas concentration of 2% or less comprising contacting the treatment liquid to the substrate, the processing method of molybdenum exposed substrate according to claim 1 or 2.

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