JP2008179884A - Metal member having metal oxide film and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of forming a metal oxide film suitable for the protection of a metal containing aluminum as a main component. <P>SOLUTION: In the method of manufacturing a metal member, a metal material containing aluminum as a main component is anodized in an anodization solution having a pH of 4 to 10 and containing a nonaqueous solvent having a dielectric constant smaller than that of water and capable of dissolving water, thereby forming a nonporous amorphous aluminum oxide passivation film on a surface of the metal member. In the step of controlling the viscosity, the viscosity of the anodization solution is lowered by elevating the temperature of the anodization solution above the room temperature or by adding to the anodization solution a substance having a dielectric constant smaller than that of water and a viscosity lower than that of the nonaqueous solvent. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a metal member having a metal oxide film and a method for manufacturing the metal member, and in particular, a metal member having a metal oxide film suitable for use in a manufacturing apparatus used in a manufacturing process of an electronic device such as a semiconductor or a flat display. And a manufacturing method thereof.

  Manufacturing apparatuses used in the field of manufacturing electronic devices such as semiconductors and flat displays include, for example, chemical vapor deposition (CVD), physical vapor deposition (PVD), vacuum deposition, sputter deposition, and microwaves. A vacuum thin film forming apparatus used for excited plasma CVD and the like, a dry etching apparatus (hereinafter collectively referred to as a vacuum apparatus) used for plasma etching, reactive ion etching (RIE), and recently developed microwave excited plasma etching, and the like. There are cleaning devices, baking devices, heating devices, and the like. In recent years, as a structural material having a surface in contact with a corrosive fluid, radicals, and irradiated ions of these devices, a lightweight and strong metal mainly composed of aluminum has been widely used instead of a stainless steel material. In these devices, in order to realize efficient multi-product low-volume production in the future, a three-dimensional three-dimensional cluster tool that can handle multiple processes with a single unit, and gas types can be switched in a single process chamber. It is required to perform a plurality of processes. Aluminum belongs to a particularly basic class of practical metals, and it is necessary to form a protective film by an appropriate surface treatment for aluminum and metals containing aluminum as a main component.

  As a surface protective film when a metal containing aluminum as a main component is used as a structural material, an anodized film (anodized) by anodization in an electrolytic solution has been known for a long time. When an acidic electrolytic solution (usually pH 2 or lower) is used as the electrolytic solution, a smooth and uniform alumite film having a porous structure can be formed.

  Moreover, since the alumite film has corrosion resistance and the acidic electrolyte is stable and easy to manage, it is widely used. However, the alumite film having a porous structure is vulnerable to heat as the surface treatment of the structural member, and cracks are generated due to the difference in thermal expansion coefficient between the aluminum base material and the alumite film (Patent Document 1—Japanese Patent Laid-Open No. 10-13084). The generation of particles, corrosion due to the exposure of the aluminum base material, and the like.

  Further, a large amount of moisture or the like is accumulated and adsorbed inside the pores of the porous structure (Japanese Patent Publication No. 5-053870), and this is released in a large amount as an outgas component. For this reason, there are many problems such as significant deterioration of the performance of these vacuum devices, malfunction of devices, and the cause of corrosion of alumite film and aluminum substrate due to coexistence with various gases and chemicals including halogen gas. Had a point. Among the halogen gases, especially chlorine gas is used for etching gas in processing of metal materials in reactive ion etching (RIE), etc., and in the cleaning process of thin film forming equipment and dry etching equipment. The metal surface treatment of apparatus members having strong corrosion resistance against gas is important.

  Therefore, various alumite coatings having a low increase rate of cracks due to high-temperature heat load and various methods for forming them have been proposed. For example, a method of forming an alumite film in which the alloy composition of aluminum is controlled has been proposed (Patent Document 3-JP-A-11-181595). However, this alumite film also has a porous structure on the surface as in the prior art, and various problems due to moisture remaining in the pores of this porous structure remain unsolved.

  Various methods have been proposed to improve the problems caused by the porous structure. For example, anodized anodized anodized in an acidic electrolyte is immersed in boiling water or treated in pressurized water vapor to form aluminum hydroxide (boehmite layer) on the surface to close the pores. Sealing treatment (Patent Document 4-Japanese Patent Laid-Open No. 5-114582) or sealing treatment in a solution containing a metal hydrate or hydrated oxide as a main component (Patent Document 5-Japanese Patent Application Laid-Open No. 060044) has been proposed. However, moisture still remains inside the pores of the porous structure after the sealing treatment, and the boehmite layer itself made of aluminum hydroxide is also a hydrate, so depending on conditions such as pressure and temperature, the moisture supply source This has not led to a fundamental solution. Further, a method of performing anodizing treatment of a barrier structure after forming a porous alumite film (Patent Document 6-Japanese Patent Application Laid-Open No. 2005-105300) is also proposed, but it is necessary to perform two-step anodizing treatment. For this reason, there is a problem that the manufacturing cost becomes high.

  In addition, as a surface treatment when a metal whose main component is aluminum is used as a structural member, a thermal spraying method in which a metal / alloy, various ceramics, or a powder material in which a ceramic and a metal or alloy are combined is melted and sprayed is used. (Patent Document 7-Japanese Patent Laid-Open No. 9-069514). However, in the surface treatment by the thermal spraying method, it is difficult to suppress the formation of pores in which the film surface and the substrate are connected by holes. Therefore, when corrosive gas such as halogen gas is used in the apparatus, There remains a problem that the portion in contact with the metal whose main component is aluminum corrodes.

Japanese Patent Laid-Open No. 10-130884 Japanese Patent Publication No. 5-053870 Japanese Patent Laid-Open No. 11-181595 Japanese Patent Laid-Open No. 5-114582 JP 2004-060044 A JP 2005-105300 A Japanese Patent Laid-Open No. 9-069514 Japanese Patent Application No. 2005-178562 Japanese Patent Application No. 2006-64923 PCT International Application No. PCT / JP2006 / 309327

That is, the alumite film formed by the acidic electrolyte has a problem of residual and adsorbed moisture. In the method of anodizing the barrier structure after forming the porous alumite film, formation of voids or formation of gas pools It was difficult to completely suppress the formation of pores, and it was difficult to suppress the formation of pores by the surface treatment by the thermal spraying method. The anodized film has an Al ₂ O ₃ .nH ₂ O structure containing moisture, and the film is etched and porous by OH ions generated by electrolysis of the chemical conversion solution, so that it contains a large amount of water. For example, when used in an RIE apparatus, a large amount of moisture is released into the chamber during the etching process and becomes water plasma. Since this water plasma generates OH radicals and decomposes the photoresist, the selection ratio between the resist and the material to be etched is greatly reduced. Therefore, in conventional RIE, the resist has to be formed thick. That creates the problem of reduced resolution. In addition, a large amount of moisture released into the chamber aggregates ions in the chamber by a gas phase reaction, and a large amount of dust is generated in the chamber, leading to deterioration in device yield. In RIE, etching is usually performed at 20 to 40 millitorr, so the gas molecule interval is sufficiently wide and no gas phase reaction should occur and no dust should be generated. However, in reality, a large amount of dust is generated and dust is attached to the gate valve. There is a problem in that dust adheres to the wafer when a wafer is taken in and out, resulting in a defective product. This is because dust is generated due to moisture.

  Even if heat treatment is performed in order to release the moisture of the conventional anodized aluminum, cracking occurs at 140 ° C., so the moisture cannot be reduced by the heat treatment.

In order to solve such a problem, the inventor has released the moisture released from the metal oxide film of aluminum by anodizing a metal mainly composed of aluminum with a chemical conversion solution having a neutral pH or a neutral pH. A nonporous amorphous aluminum oxide passive film having an amount of 1E18 molecules / cm ² or less was obtained, and it was found that cracks due to annealing did not occur, and resistance to chlorine gas exposure was excellent (Patent Document 8). 9, 10).

  However, when trying to obtain a high quality and thick aluminum oxide film, there is a limitation on the ultimate voltage in the case of anodizing, and there is also a limitation on the thickness of the aluminum oxide passivation film as a protective film. That is, a good film thickness was only obtained up to about 0.35 μm at an ultimate voltage of 200V. For this reason, the aluminum oxide passivation film is thin, and it has been desired to realize a method capable of forming a thicker aluminum oxide passivation film in terms of mechanical strength and corrosion resistance.

  Accordingly, an object of the present invention is to provide a method for producing a metal member having an aluminum oxide passivated film that can be formed with a good quality and a thick film thickness, in connection with an improvement of the method for forming an aluminum oxide passivated film.

  Another object of the present invention is to provide a metal member having an aluminum passivated film by the above production method.

  The present inventors have intensively studied to achieve the above object. The cause of limiting the ultimate voltage in anodization is considered to be that the water contained in the chemical conversion solution is electrolyzed by increasing the voltage in the process of anodization. Then, it has been found that the formation voltage can be increased by using a main solvent having a small dielectric constant capable of suppressing water electrolysis.

  Specifically, it has been found that, in the case of diethylene glycol rather than ethylene glycol as the main solvent of the chemical conversion liquid, a good non-porous aluminum oxide passive film can be obtained even at an ultimate voltage of 300V.

  However, if the ultimate voltage is further increased, the surface of the aluminum oxide film becomes rough, the amount of emitted gas increases, and the corrosion resistance also decreases. This is presumably because diethylene glycol has a relatively high viscosity and charge concentration occurs during anodic oxidation, resulting in a non-uniform film.

  Therefore, it was found that when a method of controlling the viscosity of the chemical conversion solution was attempted, first, the temperature was raised from room temperature and anodization was performed, and a uniform film was obtained. The reason is considered to be that the viscosity is lowered by increasing the temperature and the way of electricity in the chemical conversion liquid becomes uniform. As another method for controlling the viscosity, another non-aqueous organic solvent having a viscosity smaller than that of the main solvent was added to an organic main solvent such as ethylene glycol or diethylene glycol to reduce the viscosity of the chemical conversion solution and anodize it. As a result, it was found that a nonporous aluminum oxide passive film having good film quality was obtained.

  Therefore, according to the present invention, a metal material mainly composed of aluminum is anodized in a chemical solution having a dielectric constant smaller than that of water and a non-aqueous solvent that dissolves water, and has a pH of 4 to 10. In the method for producing a metal member for forming a nonporous amorphous film aluminum oxide passive film on the surface, there is obtained a method for producing a metal member comprising a step of controlling the viscosity of the chemical conversion liquid.

  A viscosity control process includes the process of making the temperature of the said chemical conversion liquid higher than room temperature, and performing the said anodic oxidation.

  A viscosity control process includes the process of maintaining the temperature of the said chemical conversion liquid at 30 to 70 degreeC, and performing the said anodic oxidation.

  The viscosity control step includes a step of adding a substance having a dielectric constant smaller than that of water and a viscosity smaller than that of the non-aqueous solvent to the chemical conversion liquid.

  The viscosity control step includes a step of setting the viscosity of the chemical conversion liquid to 2 to 50 mPa · s.

  Desirably, the said viscosity control process includes the process which makes the viscosity of the said chemical conversion liquid 2-10 mPa * s.

  Preferably, the chemical conversion liquid is characterized by containing an electrolyte that renders the chemical conversion liquid electrically conductive and has a pH of 5.5 to 8.5.

  More preferably, the chemical conversion solution contains 50% by weight or less of water and has a pH of 6-8.

  The electrolyte contains at least one selected from the group consisting of boric acid, phosphoric acid, organic carboxylic acid, and salts thereof.

  Preferably, the anodic oxidation includes the step of disposing the metal material and the predetermined electrode in the chemical conversion solution, the constant current step of flowing a constant current between the metal material and the electrode for a predetermined time, A constant voltage step of applying a constant voltage between the metal material and the electrode for a predetermined time.

  The predetermined time of the constant current process is a time until the voltage between the metal material and the predetermined electrode reaches a predetermined value.

  The predetermined time of the constant voltage process is until the current between the metal material and the predetermined electrode reaches a predetermined value.

  Preferably, the method includes a step of heat-treating the metal material at a predetermined temperature of 150 ° C. or higher after the anodic oxidation.

  More preferably, the method includes a step of heat-treating the metal material at a predetermined temperature of 300 ° C. or higher after the anodic oxidation.

  In the constant current step, a current of 0.01 to 100 mA per square cm is passed.

  Preferably, the current is 0.1 to 10 mA per square centimeter.

  More preferably, the current is 0.15 to 1.5 mA per square centimeter.

  In the constant voltage step, a voltage is applied so that the chemical conversion solution does not cause electrolysis.

  The non-aqueous solvent includes at least one of ethylene glycol, diethylene glycol, triethylene glycol, and tetraethylene glycol.

  The electrolyte includes adipate.

  The metal material mainly composed of aluminum contains 50% by weight or more of aluminum.

  The metal material containing aluminum as a main component contains 1 to 4.5% by weight of magnesium.

  The metal material containing aluminum as a main component contains 0.15% by weight or less of zirconium.

  Preferably, the metal material mainly composed of aluminum has a total content of elements other than aluminum, magnesium and zirconium of 1% by weight or less.

  More preferably, in the metal material mainly composed of aluminum, the content of elements other than aluminum, magnesium and zirconium is 0.01% by weight or less.

According to the present invention, a metal oxide film having a thickness of 10 nm or more and 10 μm or less formed by the above manufacturing method and a water release amount from the film of 1E18 molecule / cm ² or less is provided on the surface. The metal member which has is obtained.

  The metal mainly composed of high-purity aluminum is a metal mainly composed of aluminum and has a total content of specific elements (iron, copper, manganese, zinc, chromium) of 1% or less. . The metal mainly composed of high-purity aluminum preferably contains at least one metal selected from the group consisting of magnesium, titanium and zirconium.

  Since the anodization is performed by using a chemical conversion solution having a pH of 4 to 10 and controlling the viscosity of the chemical conversion solution, a metal member having a thick nonporous amorphous film aluminum oxide passive film is obtained. In addition, a metal member having a nonporous amorphous film aluminum oxide passive film having a small residual current during anodic oxidation and thus excellent film quality can be obtained. In addition, the anodizing time can be shortened to increase productivity.

  Hereinafter, the present invention will be described in more detail.

The metal oxide film according to the present invention is a film made of an oxide of a metal containing aluminum as a main component or a metal containing high-purity aluminum as a main component, and has a thickness of 10 nm or more, and is emitted from the film. The water content is 1E18 molecule / cm ² or less. When this film is formed on a substrate made of a metal containing aluminum as a main component, it exhibits high performance as a protective film.

  The thickness of the metal oxide film is preferably as thin as 100 μm or less. If the film is thick, cracks are likely to occur and outgas is likely to be released. More preferably, it is 10 μm or less, more preferably 1 μm or less, particularly preferably 0.9 μm or less, and particularly preferably 0.8 μm or less. However, the film thickness is 10 nm or more. If the film thickness is too thin, sufficient corrosion resistance cannot be obtained. Preferably it is 20 nm or more, More preferably, it is 30 nm or more.

The amount of water released from the metal oxide film is 1E18 molecules / cm ² or less. When the amount of released water is large, the moisture becomes a source of corrosion, and when used as a protective film for a structural material such as an inner wall of a vacuum apparatus or the like, the quality of the manufactured thin film is deteriorated. Preferably it is 2E17 molecule / cm ² or less, more preferably 1E17 molecule / cm ² or less. The amount of water released is preferably small, but is usually 1.5E15 molecules / cm ² or more.

  Such a metal oxide film is a barrier-type metal oxide film, and has excellent corrosion resistance while being a thin film, and has few advantages of adsorbing moisture and the like because it has few micropores and pores.

  The metal oxide film according to the present invention is made of a metal oxide containing aluminum as a main component. The metal containing aluminum as a main component refers to a metal containing 50% by weight or more of aluminum. Pure aluminum may be used. Preferably, the metal contains 80% by weight or more of aluminum, more preferably 90% by weight or more, and still more preferably 94% by weight or more of aluminum. The metal containing aluminum as a main component may be pure aluminum, but may contain any other metal capable of forming an alloy with aluminum as necessary, or may contain two or more kinds. Although the kind of metal is not specifically limited, As a preferable metal, at least 1 or more types of metal chosen from the group which consists of magnesium, titanium, and a zirconium is mentioned. Of these, magnesium is particularly preferred because it has the advantage of improving the strength of the aluminum substrate.

  Furthermore, the metal oxide film according to the present invention is a metal mainly composed of aluminum, and is composed mainly of high-purity aluminum in which the content of specific elements (iron, copper, manganese, zinc, chromium) is suppressed. Made of metal oxide. The total content of these characteristic elements is preferably 1.0% by weight or less, more preferably 0.5% by weight or less, and still more preferably 0.3% by weight or less. The metal containing high-purity aluminum as a main component may be pure aluminum, but may contain any other metal capable of forming an alloy with aluminum as required, or may contain two or more kinds. . The type of metal is not particularly limited as long as it is other than the above-mentioned specific elements, but preferred metals include at least one metal selected from the group consisting of magnesium, titanium and zirconium. Of these, magnesium is particularly preferred because it has the advantage of improving the strength of the aluminum substrate. The magnesium concentration is not particularly limited as long as it can form an alloy with aluminum, but is usually 0.5% by weight or more, preferably 1.0% by weight or more, in order to bring about a sufficient strength improvement. Preferably it is 1.5 weight% or more. In order to form a uniform solid solution with aluminum, it is preferably 6.5% by weight or less, more preferably 5.0% by weight, still more preferably 4.5% by weight or less, and most preferably 3% by weight. It is as follows. Usually, it is in the range of 1 to 4.5% by weight. When magnesium is contained, there is an effect of improving mechanical strength.

  In addition, the metal mainly composed of aluminum or the metal mainly composed of high-purity aluminum according to the present invention may contain other metal components as a crystal modifier. There is no particular limitation as long as it has a sufficient effect on crystal control, but zirconium or the like is preferably used. Zirconium is preferably 0.15% by weight or less. More preferably, the content is preferably 0.1% by weight or less. This can further increase the mechanical strength and heat resistance.

  When these other metals are contained, the content thereof is usually 0.01% by weight or more, preferably 0.05% by weight or more, based on the whole metal mainly containing aluminum or high purity aluminum. More preferably, the content is 0.1% by weight or more. This is because the characteristics of the other added metals are sufficiently exhibited. However, it is usually 20% by weight or less, preferably 10% by weight or less, more preferably 6% by weight or less, particularly preferably 4.5% by weight or less, and most preferably 3% by weight or less. Aluminum and other metal components form a uniform solid solution, and in order to maintain good material properties, it is better to have less than this.

  The metal containing aluminum as a main component or the high-purity aluminum metal preferably has a total content of elements other than aluminum, magnesium and zirconium of 1% by weight or less. Moreover, it is preferable that content of these elements except aluminum, magnesium, and zirconium is 0.01 weight% or less. If these impurity elements exceed the above content, oxygen is generated in the oxide film, voids are generated, and cracks are generated during annealing. In addition, the residual current of the film is increased. In particular, when the total content of elements other than aluminum, magnesium and zirconium is 0.01% by weight or less, a sufficiently low residual current density in anodic oxidation can be obtained, and a dense oxide film can be formed.

  Next, the manufacturing method of the oxide film of the metal member which has the metal which has aluminum as a main component of this invention, or a high purity aluminum as a main component is demonstrated.

  According to the method of anodizing a metal containing aluminum as a main component or a metal containing high-purity aluminum as a main component in a chemical conversion solution having a pH of 4 to 10, a dense and pore-free barrier metal oxide film can be obtained. In general, a substrate made of a metal mainly composed of aluminum is anodized in a chemical conversion solution having a pH of 4 to 10, whereby a film made of an oxide of a metal mainly composed of aluminum is formed on the surface of the substrate.

  Since this method has a function of repairing defects caused by non-uniformity of the substrate, there is an advantage that a dense and smooth oxide film can be formed. The chemical conversion solution used in the present invention has a pH of usually 4 or higher, preferably 5 or higher, more preferably 6 or higher. Moreover, it is 10 or less normally, Preferably it is 9 or less, More preferably, it is 8 or less. It is desirable that the pH is close to neutral so that the metal oxide film produced by anodic oxidation is difficult to dissolve in the chemical conversion solution.

  The chemical conversion liquid used in the present invention preferably exhibits a buffering action in the range of pH 4 to 10 in order to buffer the concentration fluctuation of various substances during chemical conversion and keep the pH in a predetermined range. For this reason, it is desirable to include compounds such as acids and salts that exhibit a buffering action. The type of such a compound is not particularly limited, but is preferably at least one selected from the group consisting of boric acid, phosphoric acid, organic carboxylic acid, and salts thereof from the viewpoint of high solubility in the chemical conversion solution and good dissolution stability. is there. More preferably, it is an organic carboxylic acid or a salt thereof in which boron and phosphorus elements hardly remain in the metal oxide film.

  The metal oxide film produced by the anodizing treatment takes in a very small amount of solute components, but when used in a vacuum thin film forming apparatus or the like by using an organic carboxylic acid or a salt thereof as the solute, This is because there is no possibility of boron and phosphorus elements eluting from the film, and the quality of the formed thin film and the performance and stability of devices using the same can be expected.

  The organic carboxylic acid only needs to have one or more carboxyl groups, and may have a functional group other than the carboxyl group as long as the desired effect of the present invention is not impaired. For example, formic acid can also be preferably used. In terms of high solubility in the chemical conversion liquid and good dissolution stability, aliphatic carboxylic acids are preferable, and aliphatic dicarboxylic acids having 3 to 10 carbon atoms are particularly preferable. Examples of the aliphatic dicarboxylic acid include, but are not limited to, malonic acid, maleic acid, fumaric acid, succinic acid, tartaric acid, itaconic acid, glutaric acid, dimethylmalonic acid, citraconic acid, citric acid, adipic acid, heptanoic acid, pimeline. Examples include acid, suberic acid, azelaic acid, and sebacic acid. Of these, tartaric acid, citric acid, and adipic acid are particularly preferred for reasons such as solution stability, safety, and good buffer action. Of these, one type may be used, or two or more types may be used in combination.

  As salts of boric acid, phosphoric acid and organic carboxylic acid, salts of these acids with appropriate cations may be used. The cation is not particularly limited, and for example, ammonium ion, primary, secondary, tertiary or quaternary alkyl ammonium ion, alkali metal ion, phosphonium ion, or sulfonium ion can be used. Of these, ammonium ions, primary, secondary, tertiary or quaternary alkylammonium ions are preferred in that they are less affected by residuals due to diffusion to the substrate metal due to residual metal ions on the surface. The alkyl group of the alkyl ammonium ion may be appropriately selected in consideration of solubility in the chemical conversion solution, but is usually an alkyl group having 1 to 4 carbon atoms.

  These compounds may be used alone or in combination of two or more. Moreover, the chemical conversion liquid concerning this invention may contain another compound in addition to said compound.

  The concentration of these compounds may be appropriately selected according to the purpose, but is usually 0.01% by weight or more, preferably 0.1% by weight or more, more preferably 1% by weight or more based on the whole chemical conversion liquid. And Increasing the electrical conductivity is desirable in order to sufficiently form the metal oxide film. However, it is usually 30% by weight or less, preferably 15% by weight or less, and more preferably 10% by weight or less. In order to keep the performance of the metal oxide film high and to reduce the cost, it is desirable that it be less than this.

  The chemical conversion liquid used in the present invention preferably contains a non-aqueous solvent. The use of a chemical conversion solution containing a non-aqueous solvent has an advantage that it can be processed at a high throughput because the time required for the constant current conversion is shorter than that of an aqueous chemical conversion solution.

  The type of the non-aqueous solvent is not particularly limited as long as it can be anodized satisfactorily and has sufficient solubility in a solute, but a solvent having one or more alcoholic hydroxyl groups and / or one or more phenolic hydroxyl groups, Or an aprotic organic solvent is preferable. Among these, a solvent having an alcoholic hydroxyl group is preferable from the viewpoint of storage stability.

  Particularly preferred as a non-aqueous solvent is that the water has a dielectric constant of about 80 in order to prevent decomposition of water in the chemical conversion solution and prevent the grown aluminum oxide film from being etched, but the binding energy of the material is dielectric. Since it is inversely proportional to the square of the rate, an organic solvent having a dielectric constant smaller than that of water and a low vapor pressure is preferable. For example, ethylene glycol has a dielectric constant of 39, diethylene glycol has a dielectric constant of 33, triethylene glycol has 24, and tetraethylene glycol has 20. Therefore, the use of these organic solvents can effectively lower the dielectric constant and increase the ultimate voltage without causing water electrolysis. These may be used alone or in combination. Moreover, if it contains the nonaqueous solvent, you may contain water.

  The non-aqueous solvent is usually contained in an amount of 10% by weight or more, preferably 30% by weight or more, more preferably 50% by weight or more, and particularly preferably 55% by weight or more based on the whole chemical conversion liquid. However, it is usually 95% by weight or less, preferably 90% by weight or less, particularly preferably 85% by weight or less.

  When the chemical conversion liquid contains water in addition to the non-aqueous solvent, the content thereof is usually 1% by weight or more, preferably 5% by weight or more, more preferably 10% by weight or more, and particularly preferably 15% by weight with respect to the whole chemical conversion liquid. It is at least 85% by weight, usually not more than 85% by weight, preferably not more than 50% by weight, particularly preferably not more than 40% by weight.

  The ratio of water to non-aqueous solvent is preferably 1% by weight or more, preferably 5% by weight or more, more preferably 7% by weight or more, particularly preferably 10% by weight or more, and usually 90% by weight or less, preferably 60% by weight. % By weight or less, more preferably 50% by weight or less, particularly preferably 40% by weight or less.

  In the present invention, the electrolytic method for anodic oxidation is not particularly limited as long as the intended effect of the present invention is not significantly impaired. As the current waveform, for example, in addition to direct current, a pulse method in which an applied voltage is periodically interrupted, a PR method in which the polarity is inverted, other alternating current, AC / DC superimposition, incomplete rectification, a modulation current such as a triangular wave, or the like can be used. However, preferably a direct current is used.

  In the present invention, the method for controlling the current and voltage of anodization is not particularly limited, and conditions for forming an oxide film on the surface of a metal mainly composed of aluminum can be appropriately combined. Usually, it is preferable to anodize at a constant current and a constant voltage. In other words, it is preferable that the formation is performed at a constant current up to a predetermined formation voltage Vf, and after the formation voltage is reached, the voltage is held for a certain period of time to perform anodization.

At this time, in order to efficiently form an oxide film, the current density is usually 0.001 mA / cm ² or more, preferably 0.01 mA / cm ² or more. However, in order to obtain an oxide film with good surface flatness, the current density is usually 100 mA / cm ² or less, preferably 10 mA / cm ² or less.

  The formation voltage Vf is usually 3 V or higher, preferably 10 V or higher, more preferably 20 V or higher. Since the obtained oxide film thickness is related to the formation voltage Vf, it is preferable to apply the voltage or more in order to give a certain thickness to the oxide film. However, it is usually 1000 V or less, preferably 700 V or less, more preferably 500 V or less. Since the obtained oxide film has a high insulating property, it is preferable to carry out at or below the above voltage in order to form a high-quality oxide film without causing dielectric breakdown.

  In order to increase the thickness of the oxide film, it is necessary to increase the chemical conversion voltage. In this case, the ultimate voltage depends on the type of chemical conversion solution. Using diethylene glycol as the main solvent can increase the ultimate voltage compared to using ethylene glycol as the main solvent. For this reason, in ethylene glycol, the ultimate voltage for obtaining a good quality aluminum oxide film is 200 V, and the film thickness at that time is about 0.35 μm, but in diethylene glycol, the ultimate voltage can be increased to 300 V. A good quality aluminum oxide film of 45 μm can be formed.

  Alternatively, a method may be used in which an alternating current having a constant peak current value is used instead of the direct current power source until reaching the formation voltage, and when the formation voltage is reached, the direct current voltage is switched to the direct current voltage and held for a certain period of time.

  In the present invention, an organic solvent such as ethylene glycol, diethylene glycol, triethylene glycol, or tetraethylene glycol is used singly or in combination, which is important in forming an aluminum oxide film having a high chemical conversion temperature. Usually, a temperature higher than room temperature is preferred. More preferably, it is the range of 30 degreeC-70 degreeC.

  According to another aspect of the present invention, the chemical conversion liquid contains, in addition to the main solvent, another non-aqueous solvent having a dielectric constant smaller than that of water and a viscosity lower than that of the main solvent. For example, it is a non-aqueous solvent having a lower viscosity than the main solvent such as isopropyl alcohol (IPA), acetone, dimethyl sulfoxide (DMSO), N, N-dimethylformamide (DMF), dioxane and the like. The ratio of these solvents to the main solvent is preferably 5% by weight or more, more preferably 10% by weight or more, particularly preferably 15% by weight or more, and usually 50% by weight or less, preferably 40% by weight or less, Preferably, it is 35% by weight or less, particularly preferably 30% by weight or less.

  An organic solvent having a chemical conversion temperature higher than room temperature and / or a viscosity lower than that of the main solvent lowers the viscosity of the chemical conversion liquid, imparts uniformity as a whole chemical conversion liquid, and imparts uniform electrical conduction to the chemical conversion liquid. Since the film can be formed at a higher formation voltage, the film thickness can be increased. Further, a uniform oxide film with good quality can be obtained.

  The viscosity of the chemical conversion liquid thus controlled is desirably 2 to 50 mPa · s. More preferably, it is 2 to 10 mPa · s.

  An electrolyte that makes the chemical conversion liquid electrically conductive is added to the chemical conversion liquid. As a result, if the chemical conversion liquid becomes acidic, the aluminum member is corroded. Therefore, an electrolyte that can prevent corrosion of aluminum, for example, adipate, is provided with a pH of 4 to 10, preferably 5.5 to 8.5, more preferably 6 to 8 while increasing the electrical conductivity of the chemical conversion liquid. Use. The content is 0.1 to 10% by weight, preferably about 1%. In a typical example, a chemical conversion solution of 79% organic solvent, 20% water and 1% electrolyte is used. More preferably, the chemical conversion liquid has a water content of 50% by weight or less and a pH of 6-8.

  The anodic oxidation includes a first step of placing the metal material (metal material substrate) and a counter electrode (for example, platinum) in the chemical conversion liquid, and applying a plus to the metal material and a minus to the counter electrode. Preferably, the method includes a second step of flowing a constant current for a predetermined time, and a third step of applying a constant voltage between the metal material and the electrode for a predetermined time. The predetermined time in the second step is preferably until the voltage between the metal material and the predetermined electrode reaches a predetermined value (for example, until 300 V when diethylene glycol is used).

  The predetermined time of the third step is preferably until the current between the metal material and the predetermined electrode reaches a predetermined value, but the current value rapidly increases when the voltage reaches the predetermined value. It decreases, and then gradually decreases with time. The smaller the residual current is, the better the quality of the oxide film is. However, for example, if a constant voltage process is performed for 24 hours, the film quality becomes equivalent to that obtained by heat treatment. In order to increase productivity, the constant voltage treatment may be stopped and heat treatment (annealing) may be performed at an appropriate time. The heat treatment is preferably performed at 150 ° C. or more and about 300 ° C. for 0.5 to 1 hour.

  In the second step, a current of 0.01 to 100 mA, preferably 0.1 to 10 mA, more preferably 0.15 to 1.5 mA is applied per square centimeter.

  As described above, in the third step, the voltage is set such that the chemical conversion liquid does not cause electrolysis. The thickness of the nonporous amorphous film aluminum oxide passivation film depends on the voltage in the third step.

  Although not bound by any theory, the pore-free metal oxide film formed during the chemical conversion treatment according to the present invention is because the entire film has an amorphous structure and there are almost no grain boundaries such as crystals. it is conceivable that. Further, by adding a compound having a buffering action or using a non-aqueous solvent as a solvent, a trace amount of carbon component is taken into the metal oxide film and the bonding strength of Al-O is weakened. Thus, it is presumed that the amorphous structure of the entire film is stabilized.

  The metal oxide film manufactured as described above may be subjected to heat treatment for the purpose of removing moisture in the film. A conventional metal oxide film having a porous structure may be cracked or cracked even by annealing at about 150 to 200 ° C., and heat treatment at a high temperature cannot be performed and sufficient water removal cannot be performed. It was also a cause that the amount of release could not be reduced. Since the metal oxide film according to the present invention is a dense and pore-free barrier type film, it is possible to suppress the occurrence of cracks and cracks in the annealing treatment, and to reduce the outgas emission amount from the film.

  In particular, a metal oxide film mainly composed of high-purity aluminum containing substantially no specific element has higher thermal stability than a metal oxide film mainly composed of an aluminum alloy, and voids, gas pools, etc. Is difficult to form. For this reason, voids and seams are less likely to enter the metal oxide film even by annealing at about 300 ° C. or higher, so that corrosion due to generation of particles and exposure of the aluminum substrate to chemicals and halogen gas, particularly chlorine gas, can be suppressed. Outgassing is also less advantageous.

  The heat treatment method is not particularly limited, but an annealing treatment in a heating furnace or the like is simple and preferable.

  The temperature of the heat treatment is not particularly limited as long as the desired effect of the present invention is not hindered, but is usually 100 ° C. or higher, preferably 150 ° C. or higher, more preferably 300 ° C. or higher. In order to sufficiently remove moisture on the surface and inside of the metal oxide film by heat treatment, it is preferable to perform the treatment at the above temperature or more. However, it is usually 600 ° C. or lower, preferably 550 ° C. or lower, more preferably 500 ° C. or lower. In order to maintain the amorphous structure of the metal oxide film and maintain the flatness of the surface, it is preferable to perform the treatment at the temperature or lower. In the case of annealing treatment, the set temperature of the heating furnace is usually regarded as the heat treatment temperature.

  The heat treatment time is not particularly limited as long as the desired effect of the present invention is not hindered. However, the heat treatment time may be appropriately set in consideration of the target effect, surface roughness due to the heat treatment, productivity, and the like. Minutes or more, preferably 5 minutes or more, particularly preferably 15 minutes or more. In order to sufficiently remove moisture on the surface and inside of the metal oxide film, it is preferable to perform the treatment for the above time or more. However, it is usually 180 minutes or less, preferably 120 minutes or less, more preferably 60 minutes or less. In order to maintain the metal oxide film structure and surface flatness, it is preferable to perform the treatment within the above time.

  The atmosphere in the furnace during the annealing treatment is not particularly limited as long as the effect of the treatment of the present invention is not hindered. Usually, nitrogen, oxygen, or a mixed gas thereof can be appropriately used. Of these, an atmosphere having an oxygen concentration of 18 vol% or higher is preferable, a condition of 20 vol% or higher is more preferable, and a condition of oxygen concentration of 100 vol% is most preferable.

  Next, a laminated body including a film made of an oxide of a metal containing aluminum as a main component or a metal containing high-purity aluminum as a main component and its use will be described.

  A laminate formed by forming the metal oxide film of the present invention on a base composed of a metal mainly composed of aluminum or a metal composed mainly of high-purity aluminum is used as a protective film. It shows good corrosion resistance. In addition, since the metal oxide film is not easily cracked even when it is heated, moisture in the film can be sufficiently removed by annealing or the like, and release of outgas from the film can be suppressed. Normally, corrosion of aluminum by chlorine gas requires three elements: oxidant, chlorine ion and water, but chlorine gas itself is an oxidant and can be a source of chlorine ions. Although corrosion is caused, the amount of moisture released as outgas from the metal oxide film of the present invention is extremely small, so that corrosion of aluminum can be suppressed. Further, generation of particles due to cracks and corrosion due to exposure of the aluminum substrate at the cracks can be suppressed.

  As described above, the metal oxide film according to the present invention is resistant to gases and chemicals including chlorine gas, is not easily cracked by heating, and has little outgas, so that it is a structural material for semiconductor or flat display manufacturing equipment. It is very suitable as a protective film. And the laminated body which has this metal oxide film on the base | substrate consisting of an aluminum-type metal is suitable as a structural material of a semiconductor or a flat display manufacturing apparatus. Here, the semiconductor or flat display manufacturing apparatus is a manufacturing apparatus used in the field of manufacturing semiconductors or flat displays, that is, chemical vapor deposition (CVD), physical vapor deposition (PVD), vacuum deposition, sputter deposition. This refers to a vacuum thin film forming apparatus used for the method and microwave excited plasma CVD, and a dry etching apparatus used for plasma etching, reactive ion etching (RIE), and recently developed microwave excited plasma etching.

  Prior to the description of the embodiments, conditions for realizing a higher conversion voltage in order to obtain a thicker film thickness will be described. An organic solvent having a chemical conversion temperature higher than room temperature and / or a viscosity lower than that of the main solvent lowers the viscosity of the chemical conversion liquid and imparts uniformity as a whole of the chemical conversion liquid. For this reason, uniform electric conduction is obtained in the whole chemical conversion liquid, and as a result, a higher chemical conversion voltage can be realized. FIG. 9 shows an additive solvent that has a lower dielectric constant and viscosity than the main solvent and is considered as the third component.

  13 and 14 show the relationship between the temperature and viscosity of the chemical conversion solution (electrolytic solution). The parameter is the type of chemical conversion liquid.

  FIG. 13 is a diagram obtained by first measuring the relationship between the temperature of the chemical conversion solution (electrolytic solution) and the viscosity when the solvent is ethylene glycol (EG) or diethylene glycol (DiEG). The higher the temperature, the lower the viscosity of the chemical conversion liquid. It can also be seen that ethylene glycol has a lower viscosity at each temperature than diethylene glycol.

Second, ethylene glycol (EG / 10% H ₂ O and EG / 20% H ₂ O), diethylene glycol (DiEG / 10% H ₂ O and DiEG / 20% H ₂ O) with 10% and 20% water added. ), Triethylene glycol (TriEG / 20% H ₂ O) and tetraethylene glycol (TetraEG / 20% H ₂ O). It can also be seen that the viscosity decreases when water is added, and the viscosity decreases more when the amount of water is 20% by weight than when it is 10% by weight. When IPA is added instead of water, the effect of reducing the viscosity is greater as shown by DiEG / 20% IPA.

  In FIG. 14, ethylene glycol (EG), diethylene glycol (DiEG), triethylene glycol (TriEG), and tetraethylene glycol (TetraEG) are used as the main solvent, and IPA, DMSO, and acetone are used as the third solvent. This is a characteristic when water is added. For convenience of comparison, FIG. 14 also shows a portion of the data in FIG. From this figure, it can be seen that by adding the second and third solvents having a viscosity lower than that of the main solvent, the viscosity of the entire chemical conversion solution is lowered. Further, the viscosity is further lowered at a temperature higher than room temperature.

(Example 1)
Next, anodization when diethylene glycol (DiEG) is used as the nonaqueous solvent will be described. High purity with an aluminum alloy content of specific elements including 2.0% magnesium, 0.1% zirconium, iron, copper, manganese, zinc, and chromium, 0.005% by weight and the balance aluminum An aluminum alloy (S2M) was used, an adipate was used as a solute, diethylene glycol was used as a main solvent, and anodization was performed with a chemical conversion solution having a pH of 7.0.

The elapsed time characteristics of voltage and current at that time are shown in FIG. Constant current anodization was performed at a current density of 1 mA / cm ² until the formation voltage reached 300 V (left figure), and then the voltage when the constant voltage anodization was carried out by holding at that voltage (right figure) (left figure) ) And elapsed time characteristics of current density (right figure). The parameter is 23 ° C., 40 ° C., 50 ° C. and 60 ° C., respectively, at the chemical conversion liquid temperature. From this figure, when the temperature is higher than 23 ° C., that is, when the viscosity is small, the voltage reaches 300 V at a constant current faster, the current density decreases more quickly at a constant voltage, and the current density value becomes lower. I understand. The smaller the current density, the denser the film.

  FIG. 2 is a photograph of the surface state of the metal oxide film observed after annealing the aluminum oxide film thus obtained. The higher the chemical conversion liquid temperature, the better the gloss of the surface state and the better the uniformity, that is, the higher the flatness. Since the metal oxide films obtained at 23 ° C., 40 ° C., and 50 ° C. have the same voltage value, the film thickness is 0.45 μm. FIG. 3 is a photograph of the surface of the metal oxide film after the annealing treatment observed with a scanning electron microscope. An aluminum oxide film formed at a high temperature shows a better surface state.

(Example 2)
The surface state of the aluminum oxide film obtained by anodizing the aluminum alloy and the chemical solution with the same solute, main solvent and pH as in Example 1, with a chemical conversion temperature of 23 ° C. and a chemical conversion voltage of 300 V, 350 V, and 400 V. The upper surface and the lower portion of FIG. 4 show photographs of the surface states of the aluminum oxide films obtained by setting the formation temperature to 40 ° C. and the formation voltages to 300 V, 350 V, and 400 V, respectively. When the chemical liquid temperature is increased, the surface state is a glossy surface even if the chemical voltage is increased. The thickness of the glossy aluminum oxide film obtained at 400 V and 40 ° C. was 0.6 μm. At 350V and 300V, they are 0.53 μm and 0.45 μm, respectively. According to the present invention, it can be seen that anodization at a higher voltage is possible, resulting in a thicker film.

  FIG. 5 is a photograph of the surface of the aluminum oxide film after the annealing treatment observed with a scanning electron microscope. An aluminum oxide film formed at a high temperature shows a better surface state.

  Moreover, in Example 2, the figure which shows the voltage characteristic and electric current characteristic with respect to elapsed time when forming an aluminum oxide film is shown in FIG.6, FIG.7 and FIG.8 about the case of the ultimate voltage 300V, 350V, and 400V, respectively. Indicated. In each figure, the left vertical axis indicates the voltage value, and the right vertical axis indicates the current density.

  Referring to FIG. 8, at an ultimate voltage of 400 V, the voltage characteristic when anodizing in the constant current mode at a conversion temperature of 23 ° C. loses its linearity and appears curved, whereas good linearity is obtained at 40 ° C. . Further, it is confirmed that the residual current density is smaller at 40 ° C. and a dense film can be obtained.

  FIG. 15 shows the characteristics of voltage and current change when anodizing is performed at an ultimate voltage of 400 V and a chemical conversion solution temperature of 60 ° C., as compared with the case of performing at 23 ° C. and 40 ° C. From this figure, 40 ° C and 60 ° C, that is, the smaller the viscosity, the faster it reaches 400V at constant current, the faster the current density decreases at constant voltage, and the lower the current density value. I understand.

(Example 3)
In Examples 1 and 2, diethylene glycol was used as the main solvent. In Example 3, in order to control the viscosity of the chemical conversion solution, a second component was further added to diethylene glycol and water to perform anodization. went.

  FIG. 9 shows physical properties such as viscosity and dielectric constant of the organic solvent which is the second component used.

  FIG. 10 shows an aluminum oxide film formed by anodic oxidation by adding isopropyl alcohol (IPA), acetone, dimethyl sulfoxide (DMSO), N, N-dimethylformamide (DMF) and dioxane to diethylene glycol (DiEG). It is a voltage characteristic which shows the relationship between a voltage and elapsed time. The ratio of these second components to diethylene glycol is shown in the figure. In the same figure, the case where the second component is not added to diethylene glycol (DiEG) is also shown. In addition, the case where ethylene glycol (EG) is used instead of diethylene glycol is also shown. FIG. 10 shows that the slope of up to 300 V deviates from the straight line in the case of ethylene glycol and diethylene glycol, whereas the linearity is better when the organic solvent as the second component is included. Deviation from linearity over time suggests poor film quality. That is, it can be seen from the figure that good film quality can be obtained by adding an organic solvent having a low viscosity as the second component to diethylene glycol. In addition, it can be seen from the figure that linearity is better when diethylene glycol is the main solvent than ethylene glycol, and the resulting film is denser.

  FIG. 11 shows changes in the elapsed time of the current characteristics when anodized in Example 3. From the figure, it can be seen that the current density is faster, smaller and lower when the organic solvent is included as the second component than ethylene glycol and diethylene glycol which do not include the second component.

  FIG. 12 shows the residual current density for each electrolyte used in Example 3. The residual current density is a value 30 minutes after the voltage reaches a predetermined voltage. The electrolyte solutions up to the eighth from the top of FIG. 11 are numerical values of those shown in FIG. 11. In addition, for diethylene glycol not containing the second component, the chemical solution temperature is set to other than 23 ° C. 40 ° C, 50 ° C, and 60 ° C are also shown.

Example 4
Next, with respect to the same high-purity aluminum alloy as in Example 1, the voltage-current characteristics during anodic oxidation by adding the second solvent were measured.

  FIG. 16 shows the characteristics. The case where 50% IPA and 20% IPA were added to the main solvent using diethylene glycol as the second solvent was examined. For comparison, the case where the second solvent was not added, that is, diethylene glycol was also shown. In the case of diethylene glycol, in addition to the case where the chemical conversion liquid temperature is 23 ° C., the case of 40 ° C. is also shown. From these experimental results, it can be seen that the performance when IPA is added to diethylene glycol is superior to the characteristics when IPA is not added. It can also be seen that the linearity during constant current anodization and the residual current density characteristics during constant voltage anodization are better when the liquid temperature of diethylene glycol is increased than when IPA is added.

(Example 5)
In Example 5, the relationship between the viscosity of the chemical conversion liquid and the dielectric breakdown voltage was examined. The breakdown voltage of the passive film of aluminum oxide formed in the process of anodizing a 99.999% aluminum (5N-Al) substrate was measured. If the formation voltage during anodization can be increased, a thick aluminum oxide passivation film can be obtained. However, when the formation voltage increases, the voltage applied to the formed aluminum oxide film also increases, causing dielectric breakdown. FIG. 17 plots the viscosity of the chemical conversion solution on the horizontal axis and the dielectric breakdown voltage of the aluminum oxide passivation film on the vertical axis. From the figure, it can be seen that the dielectric breakdown voltage is higher when the viscosity of the chemical conversion solution is smaller.

  As described above, according to the present invention, it is possible to provide a metal oxide film containing aluminum as a main component, in particular, a barrier type metal oxide film having no micropores or pores, and a method for producing the same. The metal oxide film and the metal member having the metal oxide film have good corrosion resistance against chemicals and halogen gas, particularly chlorine gas, and the metal oxide film is not easily cracked even when heated. Corrosion due to exposure is suppressed, thermal stability is high, and outgas emission from the film is small. When used as a protective film for structural materials such as the inner wall of a vacuum device such as a vacuum thin film forming device, it improves the ultimate vacuum of the device and improves the quality of the thin film produced. It leads to reduction.

  Further, according to the method for producing a metal oxide film of the present invention, a pore-free metal oxide film having a high withstand voltage and hardly causing cracks during heating can be efficiently formed. This metal oxide film is not only suitable as a protective film on the surface of a metal substrate, but can also be used as an impurity barrier film and anticorrosive film, and its application range is wide.

3 is a graph showing elapsed time characteristics of voltage and current of anodization in Example 1. 2 is a photograph showing a surface state of a metal oxide film of a metal member manufactured in Example 1. FIG. 2 is a photograph of the surface of the metal oxide film of the metal member manufactured in Example 1 observed with a scanning electron microscope. 4 is a photograph showing a surface state of a metal oxide film of a metal member manufactured in Example 2. FIG. It is the photograph which observed the surface of the metal oxide film of the metal member manufactured in Example 2 with the scanning electron microscope. It is a figure which shows the voltage characteristic and electric current characteristic with respect to elapsed time at the time of performing the anodic oxidation at the ultimate voltage of 300V in Example 2. FIG. It is a figure which shows the voltage characteristic and electric current characteristic with respect to elapsed time at the time of performing the anodic oxidation with the ultimate voltage of 350V in Example 2. FIG. It is a figure which shows the voltage characteristic and electric current characteristic with respect to elapsed time at the time of performing anodic oxidation with the ultimate voltage of 400V in Example 2. FIG. FIG. 4 is a diagram showing physical properties of an organic solvent that is a third component used in Example 3. It is a figure which shows the voltage characteristic with respect to the elapsed time of the anodic oxidation in Example 3. FIG. It is a figure which shows the electric current characteristic with respect to the elapsed time of the anodic oxidation in Example 3. It is the figure which put together the residual current density in Example 3. FIG. It is the figure which measured the relationship between the viscosity of a chemical liquid, and temperature using the kind of solvent as a parameter. It is another figure which measured the relationship between the viscosity of a chemical liquid, and temperature using the kind of solvent as a parameter. It is another figure which shows the voltage characteristic and electric current characteristic with respect to elapsed time at the time of performing the anodic oxidation at the ultimate voltage of 400V in Example 2. It is another figure which shows the voltage characteristic and electric current characteristic with respect to elapsed time at the time of performing anodization with the ultimate voltage of 400V in Example 4. FIG. It is a figure which shows the relationship between a chemical conversion liquid viscosity and the dielectric breakdown voltage of an anodic oxide film.

Claims (26)

  A nonporous amorphous film aluminum is formed on the surface of the metal material by anodizing a metal material mainly composed of aluminum in a chemical solution having a dielectric constant smaller than that of water and containing a non-aqueous solvent that dissolves water. In the manufacturing method of the metal member which forms an oxide passive film, it has the process of controlling the viscosity of the said chemical conversion liquid, The manufacturing method of the metal member characterized by the above-mentioned.   The method for producing a metal member according to claim 1, wherein the viscosity control step includes a step of setting the viscosity of the chemical conversion liquid to 2 to 50 mPa · s.   The method for producing a metal member according to claim 1, wherein the viscosity control step includes a step of setting the viscosity of the chemical conversion liquid to 2 to 10 mPa · s.   The said viscosity control process includes the process of making the temperature of the said chemical conversion liquid higher than room temperature, and performing the said anodic oxidation, The manufacturing method of the metal member as described in any one of Claims 1-3 characterized by the above-mentioned.   The said viscosity control process includes the process of hold | maintaining the temperature of the said chemical conversion liquid at 30 to 70 degreeC, and performing the said anodic oxidation, The manufacturing method of the metal member of Claim 4 characterized by the above-mentioned.   The said viscosity control process includes the process of adding the substance whose dielectric constant is smaller than water, and a viscosity is smaller than the said nonaqueous solvent to the said chemical conversion liquid, The any one of Claims 1-5 characterized by the above-mentioned. Manufacturing method of the metal member.   The said chemical conversion liquid contains the electrolyte which makes this chemical conversion liquid electrical conductivity, and pH is 5.5-8.5, The manufacturing method of the metal member as described in any one of Claims 1-6 characterized by the above-mentioned. .   The method for producing a metal member according to claim 7, wherein the chemical conversion solution contains 50% by weight or less of water and has a pH of 6 to 8.   The method for producing a metal member according to claim 7, wherein the electrolyte contains at least one selected from the group consisting of boric acid, phosphoric acid, organic carboxylic acid, and salts thereof.   The anodic oxidation includes a step of placing the metal material and a predetermined electrode in the chemical conversion solution, a constant current step of flowing a constant current between the metal material and the electrode for a predetermined time, and the metal material. A method of manufacturing a metal member according to claim 1, further comprising a constant voltage step of applying a constant voltage between the electrode and the electrode for a predetermined time.   The method of manufacturing a metal member according to claim 10, wherein the predetermined time of the constant current step is until a voltage between the metal member and a predetermined electrode reaches a predetermined value.   The method for manufacturing a metal member according to claim 10 or 11, wherein the predetermined time of the constant voltage step is until a current between the metal material and a predetermined electrode reaches a predetermined value.   The method for producing a metal member according to any one of claims 1 to 12, further comprising a step of heat-treating the metal material at a predetermined temperature of 150 ° C or higher after the anodization.   The method for producing a metal member according to claim 13, wherein the metal material is heat-treated at a predetermined temperature of 300 ° C or higher after the anodic oxidation.   The method for producing a metal member according to claim 10, wherein a current of 0.01 to 100 mA per square cm is passed in the constant current step.   The method of manufacturing a metal member according to claim 15, wherein the current is 0.1 to 10 mA per square centimeter.   The method of manufacturing a metal member according to claim 15, wherein the current is 0.15 to 1.5 mA per square centimeter.   The method for producing a metal member according to any one of claims 10 to 17, wherein a voltage is applied so that the chemical conversion liquid does not cause electrolysis in the constant voltage step.   The method for producing a metal member according to claim 1, wherein the non-aqueous solvent includes at least one of ethylene glycol, diethylene glycol, triethylene glycol, and tetraethylene glycol.   The said electrolyte contains adipate, The manufacturing method of the metal member as described in any one of Claims 7-19 characterized by the above-mentioned.   The method for producing a metal member according to any one of claims 1 to 20, wherein the metal material containing aluminum as a main component contains 50 wt% or more of aluminum.   The method for producing a metal member according to claim 21, wherein the metal material containing aluminum as a main component contains 1 to 4.5% by weight of magnesium.   The method for producing a metal member according to claim 22, wherein the metal material mainly composed of aluminum contains 0.15 wt% or less of zirconium.   The method for producing a metal member according to claim 22 or 23, wherein the metal material mainly composed of aluminum has a total content of elements other than aluminum, magnesium and zirconium of 1 wt% or less.   25. The method for producing a metal member according to claim 24, wherein the metal material containing aluminum as a main component has a content of elements other than aluminum, magnesium and zirconium of 0.01% by weight or less. Metal oxidation in which the thickness of the film formed by the manufacturing method according to any one of claims 1 to 25 is 10 nm or more and 10 μm or less, and the amount of water released from the film is 1E18 molecule / cm ² or less. A metal member having a material film on its surface.