JP2005163134A - Pore structure, and its production method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pore structure which can exhibit various functions, and to provide its production method. <P>SOLUTION: The method of producing a pore structure is the one where a mating cathode 5 is confronted with a substrate 4 as an anode, and anodization treatment is performed in a solution 3 to form pores on the surface of the substrate 4. The method includes: a stage where the mating cathode 5 is confronted with the region 4a in the substrate 4, and the first anodization treatment is performed to form pores having a first diameter on the region 4a; a stage where the mating cathode 5 is scanned to the position confronted with the region 4b in the substrate 4 relatively to the substrate 4; and a stage where the mating cathode 5 is confronted with the region 4b, and the second anodization treatment is performed under the conditions different from those in the first anodization treatment, thus pores having a second diameter different from the first diameter are formed on the region 4b. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a pore structure and a method for producing the same, and more particularly to a pore structure used for a mold, a mask material, a light emitting element and a filter material, and a method for producing the same.

  Lithography technology is common as a method of creating upright pores. The pores are directly formed by a semiconductor processing technique in which photolithography, electron beam exposure, X-ray exposure, and the like are combined with an etching technique. In this case, in order to reduce the pore diameter, it is necessary to shorten the exposure wavelength. However, the processing cost is increased, and new developments such as a mask material and a lens diameter are necessary.

  In order to manufacture an upright pore structure at a low cost, there is a method of forming pores in a self-organized manner, and this method includes an anodizing treatment. In this method, an electric field treatment is performed in an acidic solution such as sulfuric acid, oxalic acid, or hydrofluoric acid, and the anode side is oxidized to obtain upright pores. Al (aluminum) is well known as an anode material, but a similar structure can be obtained with Si (silicon) or the like. The diameter of the pores and the interval between the pores can be controlled by adjusting the current and voltage during the anodizing treatment.

  In addition, a method of introducing a pore starting point in advance in order to improve the position controllability of the pore has been proposed. As this method, a method of forming a depression on the surface of a workpiece by press patterning (Japanese Patent Laid-Open No. 10-121292), a method of using a non-resist portion as a pore origin using interference exposure by photolithography (Japanese Patent Laid-Open No. 2000). No. 315785) and a method of creating a pore forming region and a non-pore forming region by controlling the depth of the pore starting point (JP 2001-213700 A).

  Such a structure having upright pores can express various functions, but in the prior art, the function is limited because the pore diameter is single in the same plane. In order to realize different pore diameters in the same plane, it is possible to combine pore structures having various pore diameters created individually by bonding or the like. However, this method has a problem that the bonding cost is high and the area unit of the region having the same pore diameter that can be bonded can only be large. Moreover, since the pore diameter obtained by these methods is large, even if regions having different pore diameters can be formed in the same plane, the function may not be exhibited at all.

Further, as a method of forming an oxide film by operating a counterpart negative electrode material in an anodic oxidation treatment, JP-A-7-37790 and JP-A-9-251947 can be mentioned. However, although these methods form an oxide film, they do not form upstanding pores.
JP-A-10-121292 JP 2000-315785 A JP 2001-213700 A JP-A-7-37790 JP-A-9-251947

  As described above, the structure having the upright pores can express various functions, but in the prior art, the function is limited because the pore diameter in the same plane is single. Moreover, since the pore diameter obtained is large, even if regions having different pore diameters are formed, no function is exhibited.

  When the pore structure is used as a light emitting element, for example, there are methods of filling the inside of the pore with a semiconductor material or using the pore structure itself as the light emitting material. In this case, since the wavelength of the light emitting material depends on the pore diameter, even if the same semiconductor material is used, the wavelength of light emission is different if the pore diameter is different. However, since the conventional technology has a single pore diameter in the same plane, only light having a single wavelength can be obtained. In addition, the pore size that affects the emission wavelength is at most 100 nm.

  Further, when the pore structure is used as, for example, a filter function material, molecules depending on the size of the pore diameter can be separated by flowing the molecules on the surface of the pore structure. However, in the prior art, since the pore diameter in the same plane is single, only a single size molecule could be separated. Further, considering the size of the molecule, the pore size size that can be used for separation is at most 100 nm.

  Therefore, an object of the present invention is to provide a pore structure capable of expressing various functions and a method for producing the same.

The pore structure of the present invention includes a membrane having upright pores formed on a plane or a curved surface, and the pores formed in the membrane have a diameter of 0.1 nm or more and 100 nm or less. And each of the plurality of regions is formed with pores having different diameters, each of the plurality of regions having an area of 10 nm ^{2 to} 100 cm ² , and each of the plurality of regions The material of the film is an oxidized material.

  In the above pore structure, the diameter of the pores formed in the film is preferably 0.1 nm or more and 50 nm or less.

  In the above-mentioned pore structure, preferably, at least one element of Group IIB, Group IIIB, Group IVB or transition metal is contained in at least one of the constituent elements of the film.

  In the above pore structure, the distance between adjacent pores is preferably 1 nm or more and 300 nm or less.

  In the above pore structure, the pore structure is preferably used as one of a mold and a mask material.

  In the above pore structure, the pore structure is preferably used as a light emitting device.

  In the above pore structure, the pore structure is preferably used as a filter function material.

  The method for producing a pore structure of the present invention comprises a pore structure in which pores are formed by anodizing an object to be treated in a solution with an electrode to be a negative electrode facing the object to be treated as an anode. In this manufacturing method, pores having different diameters are formed in each region of the object to be processed by changing the conditions of the anodizing treatment in each region of the object to be processed.

  Preferably, in the method for manufacturing the pore structure, the object to be processed is opposed to each of the plurality of regions of the object to be processed by scanning the electrode relative to the object to be processed. Anodization is performed under different conditions for each region.

  Preferably, in the above-described method for producing a pore structure, the electrode is opposed to each of the plurality of regions of the object to be processed, and the electric resistance is set for each part of the electrode facing each of the plurality of regions of the object to be processed. And at least one of the distance from the object to be processed is different.

According to the pore structure of the present invention, pores having different diameters are formed in each of the plurality of regions, and the diameters of these pores are as small as 0.1 nm or more and 100 nm or less, and have the same diameter. Since the area of the region for forming the pores is small in the range of 10 nm ^{2 to} 100 cm ² , various functions can be expressed.

A pore having a diameter of less than 0.1 nm cannot be formed, and when the diameter exceeds 100 nm, a required function is not exhibited. In addition, when the area of the region where pores having the same diameter are formed is less than 10 nm ^{2, the} performance necessary for practical use is achieved because the number of pores is small even if the individual pores exhibit their functions. If the area exceeds 100 cm ² , the final product becomes too large to be practical.

  In addition, by using the pore structure as one of a mold and a mask material, it is possible to obtain transfer bodies having various uneven shapes in the same plane.

  Moreover, various light emission wavelengths can be obtained simultaneously by using the pore structure as a light emitting element.

  In addition, by using the pore structure as a filter function material, it is possible to filter molecules of various sizes in one operation.

  Further, according to the method for producing a pore structure of the present invention, pores having different diameters can be formed in each region of the object by changing the conditions of the anodizing treatment in each region of the object. Therefore, a large number of fine pores having different diameters can be formed in a small region. For this reason, various functions can be expressed.

  In addition, after the first anodic oxidation treatment, the electrode is scanned relative to the object to be processed to perform the second anodic oxidation treatment, and by repeating such electrode scanning and anodizing treatment. Thus, a pore structure capable of expressing various functions can be produced at low cost.

  In addition, it is possible to develop various functions by changing at least one of the electrical resistance and the distance from the object to be processed for each portion of the electrode facing each of the plurality of regions of the object to be processed. A pore structure can be manufactured at low cost.

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

  In the method for manufacturing a pore structure according to the present embodiment, anodization is performed to form a pore structure having pores having different diameters in the same plane. In this anodic oxidation treatment, a negative electrode (electrode) as a negative electrode is opposed to a substrate (object to be processed) serving as an anode in an acidic aqueous solution such as sulfuric acid, oxalic acid, and nitric acid, and direct current is applied to each of the substrate and the negative electrode. This is done by introducing power or pulsed DC power. By the introduction of this electric power, an oxide film having pores is formed on the substrate that is the anode. The pores formed at this time stand upright with respect to the substrate surface, and the pore diameter changes depending on the power value. Generally, it is said that the pore diameter increases as the power value increases. Then, by changing the conditions of the anodizing treatment between the first region and the second region of the base, pores having the first diameter are formed in the first region, and the first region is formed in the second region. A pore having a second diameter different from the diameter is formed.

  Note that a corrosion-resistant material such as platinum or nickel (Ni) is used for the counter negative electrode.

  Next, a specific method for manufacturing the pore structure according to the present embodiment will be described.

  FIGS. 1A and 1B are conceptual diagrams showing a first example of a method for manufacturing a pore structure according to an embodiment of the present invention in the order of steps. Referring to FIG. 1A, a base 4 and a counter negative electrode 5 are disposed in an electrolytic solution 3 such as sulfuric acid, oxalic acid, or hydrofluoric acid in a container 2. The counterpart negative electrode 5 is positioned so as to face the region 4 a of the base 4. In this state, a first anodic oxidation treatment is performed by applying a voltage between the base 4 and the counterpart negative electrode 5 by the DC power source 1, and an oxide film having pores having the first diameter only in the region 4a. Is formed.

  Referring to FIG. 1B, the counter negative electrode 5 is scanned relative to the substrate 4 from a position facing the region 4a to a position facing the region 4b. In the present embodiment, the base 4 is fixed and the mating negative electrode 5 moves, but the mating negative electrode 5 may be fixed and the base 4 may move, or both the base 4 and the mating negative electrode 5 move. May be. By this scanning, the counterpart negative electrode 5 is positioned so as to face the region 4 b of the base 4. In this state, a voltage is applied between the base 4 and the counterpart negative electrode 5 by the DC power source 1 to change the conditions different from the first anodizing treatment (for example, the distance between the base 4 and the counterpart negative electrode 5 is changed, or the base 4 and the counterpart negative electrode 5 are changed), the second anodic oxidation process is performed, and only the region 4b has an oxide film having pores having a second diameter different from the first diameter. It is formed.

By repeating such an operation a plurality of times, it is possible to form pores having different diameters for each region 4a, 4b, etc. in the same plane. Further, the diameter of each pore can be made as fine as 0.1 nm or more and 100 nm or less, and the area of each region 4a, 4b, etc. can be formed in the range of 10 nm ² or more and 100 cm ² or less. .

  FIG. 2 is a conceptual diagram showing a second example of a method for manufacturing a pore structure in one embodiment of the present invention. Referring to FIG. 2, a substrate 4 and a counterpart negative electrode 5 are disposed in an electrolytic solution 3 such as sulfuric acid, oxalic acid, or hydrofluoric acid in a container 2. The counterpart negative electrode 5 is positioned so that each of the portions 5 c to 5 g faces each of the regions 4 c to 4 g of the substrate 4. The surface of the counterpart negative electrode 5 facing the substrate 4 is patterned in advance, and is provided with a height difference. Thereby, each electric resistance value of each part 5c-5g of the other party negative electrode 5 and each distance from the base | substrate 4 differ. For example, the electrical resistance of the portion 5 c of the counterpart negative electrode 5 and the distance from the base 4 are different from the electrical resistances of the portions 5 d to 5 g of the counterpart negative electrode 5 and the distance from the base 4. In this state, an anodic oxidation process is performed by applying a voltage between the base 4 and the counterpart negative electrode 5 by the DC power source 1 to form oxide films having pores with different diameters in the regions 4c to 4g. Is done.

  In the above method, since the amount of current flowing into the substrate 4 varies depending on the difference in electrical resistance or the distance between the positive electrode and the negative electrode, the diameter of the pores formed in the oxide film is controlled for each of the regions 4c to 4g. It is possible. Therefore, by designing in advance how to arrange the regions having various pore diameters, by using the mating negative electrode 5 formed with electrical resistance or height difference corresponding to the pore diameter, anodizing treatment is performed, Regions having various pore sizes can be arranged as designed.

  In the above method, it is possible to use both the method based on the height difference and the method that makes the difference in electrical resistance, and the method based on the height difference and the method that makes the difference in electrical resistance can be adopted independently. is there. As a method of giving a difference in electric resistance to the mating negative electrode 5, as shown in FIG. 3, the thickness of the insulating films 6 and 7 formed on the mating negative electrode 5 is controlled, or films 6 and 7 having different electric resistances as physical properties. However, it is not particularly limited to this. Moreover, as a method of giving a height difference to the counterpart negative electrode 5, there are a mechanical scraping method, a chemical etching, a plating method, etc., but there is no particular limitation thereto.

  Also, it is within the scope of the present invention to scan the mating negative electrode 5 as shown in FIGS. 2 and 3 with respect to the base 4 to form a repeated pattern on the plane of the base 4.

  As described above, anodizing treatment is employed in the manufacture of the pore structure of the present embodiment. Thereafter, the pore diameter can be controlled using a chemical or physical etching method. In order to control the pore size, for example, chemical etching can be performed with an aqueous phosphoric acid solution or chromic acid solution, and ion etching or gas etching using a gas phase process can also be used.

  Next, the structure of the pore structure manufactured by the method of the present embodiment will be described.

FIG. 4 is a plan view showing the configuration of the pore structure manufactured by the manufacturing method according to the embodiment of the present invention. Referring to FIG. 4, the pore structure of the present embodiment includes a film 20 having upright pores 22a, 22b, and 22c formed on a plane or a curved surface. The diameters of the pores 22a, 22b, and 22c formed in the film 20 are 0.1 nm or more and 100 nm or less. The film 20 includes, for example, a region 21a having a plurality of pores 22a having a first diameter, a region 21b having a plurality of pores 22b having a second diameter different from the first diameter, and first and second And a region 21c having a plurality of pores 22c having a third diameter different from the diameter. Each planar occupation area of the regions 21a, 21b, and 21c is in the range of 10 nm ^{2 to} 100 cm ² . Each of the regions 21a, 21b, and 21c has a material obtained by oxidizing the material of the film 20 by an anodizing process.

  For example, the three regions 21a, 21b, and 21c have been described as the regions in which the pores are formed. However, if there are a plurality of regions in which the pores are formed, the number may be two, or four or more. There may be.

  In the above, the film 20 having the upright pores is a film that is subjected to an anodizing treatment, and the regions 21a, 21b, and 21c that have been subjected to the anodizing treatment, and other anodizing treatments. And not have areas. The entire film 20 may be anodized. As this film 20, for example, a bulk body of a substance capable of forming the above-mentioned pores by anodizing treatment such as Al and Ti (titanium), or Si, silica glass, silica glass on which an ITO (Indium Tin Oxide) film is formed, Substances that can form the above-mentioned pores by anodizing Al, Ti, etc. on a bulk substrate such as metal, such as vacuum deposition, electron beam deposition, various sputtering, cathodic arc discharge deposition, CVD (Chemical Vapor Deposition) method, etc. Those formed by the general thin film forming method are used. Further, the upright pores have a central axis of the pores within an angle range of −30 ° to 30 ° with respect to the surface on which the pores are formed.

  Note that the entire film 20 may be anodized.

  The diameter of the upright pores needs to be 0.1 nm or more and 100 nm or less. This is because pores having a diameter of less than 0.1 nm cannot be formed, and when the diameter exceeds 100 nm, a required function is not exhibited. Desirably, the diameter of the upright pore is 0.1 nm or more and 50 nm or less.

In addition, the planar occupation areas of the regions 21a, 21b, and 21c are in the range of 10 nm ² or more and 100 cm ² or less. However, if the planar occupation area is less than 10 nm ^{2, the} fine pores may be fine even if they function. Since the number of holes is small, performance required for practical use cannot be achieved, and when the plane occupation area exceeds 100 cm ² , the final product becomes too large to be practical.

  The film 20 included in the pore structure of the present embodiment preferably includes at least one element selected from group IIB, group IIIB, group IVB, or transition metal as at least one of the constituent elements. The film 20 may be any material as long as it can obtain upright pores by anodic oxidation treatment, and is preferably Al, Zn (zinc), Ti, Si, and these elements or each other. Even if these elements are mixed, it is only necessary to obtain upright pores.

  In the pore structure of the present embodiment, the distance L between adjacent pores 22a, 22b, or 22c is preferably 1 nm or more and 300 nm or less as shown in FIG. The distance L between adjacent pores 22a, 22b, or 22c is the thickness of the oxide wall surface 23 that isolates the pores 22a, 22b, or 22c. When the distance L is less than 1 nm, the pores 22a, 22b or 22c are too close to each other and do not work as isolated pores. When the distance L exceeds 300 nm, the density of the pores 22a, 22b, or 22c existing in one region 21a, 21b, or 21c is too low to exhibit a sufficient function.

  The pore structure of the present embodiment is preferably used as a mold or a mask material. This will be specifically described below.

  First, the pore structure of the present embodiment is formed by the above-described anodic oxidation treatment. This pore structure can be used as a mold to transfer the structure to a resin, metal, quartz, or a composite mold thereof. As a transfer method, a method generally referred to as nanoprinting technology can be used. In this technique, for example, as shown in FIG. 6A, the pore structure 25 of the present embodiment, which is a mold, is formed directly or separately on the material 30 to be transferred. The fine pore structure 25 according to the present embodiment is placed. After that, as shown in FIG. 6B, the fine structure 25 of the present embodiment is pressed to the material 30 to be transferred by pressing the pore structure 25 of the present embodiment to the material 30 to be transferred at or above the plastic deformation pressure of the material 30 to be transferred. The structure of the hole structure 25 can be transferred to the material 30 to be transferred.

  Alternatively, as shown in FIG. 7A, a resin in a liquid state and an inorganic-organic composite 40 are applied to the pore structure 25 of the present embodiment and impregnated in the pores 22 of the pore structure 25. The Thereafter, the structure of the pore structure 25 of the present embodiment can be transferred to the solidified body 40 by solidifying the liquid 40.

  The structure of the transfer material 30 or 40 is an inverted structure with respect to the structure of the pore structure 25 of the present embodiment. Thereafter, the transfer material 30 or 40 can be further transferred to obtain a structure having the same shape as the pore structure 25 of the present embodiment.

  When used as a mask material, a gas etching process is used. As shown in FIG. 8A, on the material 50 to be transferred, the pore structure 25 of the present embodiment is directly formed as a mask material, or a separate structure formed in the present embodiment. The pore structure 25 is placed, and gas etching is performed in this state. Thereby, the structure of the pore structure 25 of the present embodiment can be transferred to the material 50 to be transferred as shown in FIG. Various ion etching can be used as the etching process. In this case, the structure of the pore structure 25 as it is in this embodiment is transferred to the material 50 to be transferred.

  The pore structure of the present embodiment is preferably used as a light emitting element. When used as a light-emitting element, when light emission from the pore structure itself of the present embodiment having an oxide generated by anodization is used, or inside the pores of the pore structure of the present embodiment In some cases, a luminescent material is introduced.

  When the pore structure itself of this embodiment is used, an oxide alone may be used as such, but a certain element may be doped to improve luminous efficiency, luminous intensity, lifetime, and the like. As an element to dope, Mn (manganese) and Cr (chromium) are desirable. When introducing a luminescent material into the pores, the luminescent material is selectively introduced into the pores by using a method called electrodeposition, in which molten ions are electrically moved to react and deposit on the substrate. can do. Alternatively, the light emitting material can be dispersed in a liquid and introduced into the pores, and then the liquid can be solidified or evaporated to introduce the light emitting material into the pores. There is also a method of leaving a light-emitting material only in the pores by depositing the reaction raw material into the pores using a vapor phase process and then etching unnecessary portions. These methods are merely examples, and any method can be used as long as it can introduce a light emitting material, and a device formed thereby can be used as a light emitting element. Since the emission wavelength depends on the size of the pore diameter, when pores with different diameters are formed as in the pore structure of the present embodiment, light of various wavelengths is emitted on the same plane. It is possible to emit light.

  The pore structure of the present embodiment is preferably used as a filter function material. Since the pore structure of the present embodiment has pores having different diameters, molecules, viruses, and fungi having a size depending on the pore diameter can be separated. The above separation operation is performed by flowing a solution in which the separation target substance is dispersed on the pore structure of the present embodiment. When pores having different diameters are formed on the same plane as in the pore structure of the present embodiment, separation target substances having various sizes are continuously separated by a single separation operation. be able to.

  Examples of the present invention will be described below.

  A pore structure was produced using the method for producing a pore structure in the present embodiment, and the pore diameter was measured. In addition, the emission characteristics and separation performance were also examined. Hereinafter, the manufacturing method will be described.

(Method for producing substrate)
As a substrate, quartz glass on which Al, Ti, conductive Si, ITO thin film having a purity of 3N (99.9%) was formed was prepared. In addition, as a substrate to be prepared, a film of IIB group or IIIB group or IVB group or transition metal material such as Al, Ti, Zn (zinc), and I (yttrium) was formed on conductive Si and a graphite plate. Things were also prepared. Moreover, when using as a luminescent material, a trace amount transition metal may be doped. As a method for forming the film, sputtering, resistance heating vapor deposition, EB (Electron Beam) vapor deposition, or cathode arc vapor deposition is used. In addition, a known thin film manufacturing process such as a CVD method or a plating method can be used.

When film formation is performed by sputtering, the inside of the vacuum chamber is set to a pressure of 133.3 × 10 ⁻⁴ Pa (1 × 10 ⁻⁴ Torr) or less, and then Ar (argon) gas is introduced to form 13 in the vacuum chamber. The pressure was set to 33 mPa to 2666 mPa (0.1 mTorr to 20 mTorr). Thereafter, a negative voltage was applied so as to apply power of 100 W to 400 W to a target material (size φ4 inches) made of a metal material to be formed. Quartz glass on which conductive Si, a graphite plate, and an ITO film were formed was set as a base so as to face the target material, and the sputtered target material was deposited on the base. At this time, a negative voltage of 0 to −400 V was also applied to the substrate side.

In the resistance heating type EB vapor deposition method, the inside of the vacuum chamber is set to a pressure of 133.3 × 10 ⁻⁴ Pa (1 × 10 ⁻⁴ Torr) or lower, and then Ar gas is introduced to form 13.33 mPa in the vacuum chamber. The pressure was set to ˜2666 mPa (0.1 mTorr to 20 mTorr). Thereafter, the metal material to be formed was heated to a melting point or higher and evaporated. Quartz glass on which conductive Si, a graphite plate, and an ITO film were formed was set as a base so as to face the target material, and the evaporated target material was deposited on the base. Cathode-type arc vapor deposition was performed in the same manner, and a metal raw material was vapor-deposited by causing an arc discharge by causing a current of 30A to 100A to flow at a negative voltage to a target that is a metal material.

(Preparation method of mating negative electrode)
Au (gold), Pt (platinum), Cu (copper), or Ag (silver) was used as the material for the counterpart negative electrode. A method of providing a difference in electric resistance value in each part of the counterpart negative electrode will be described. First, a resist material, which is an insulator, was applied on the counterpart negative electrode, and the resist material was exposed to light through a previously prepared mask material. A portion of the resist material exposed by this exposure treatment was dissolved and removed with a stripping solution, thereby producing a conductive portion that was the counterpart negative electrode and an insulating portion that was the remainder of the resist material.

At this time, an unexposed portion may be dissolved and removed depending on the type of resist material. Thus, the final arrangement of the conductive portion and the insulating portion can be arbitrarily selected by selecting a negative type or a positive type of resist material or designing a mask material prepared in advance. Alternatively, an inorganic insulator such as SiO ₂ , SiN, or TiO ₂ is formed in the portion where the resist material is removed. In the case of a resist material, a material having a thickness of 10 μm to 100 μm is used, and in the case of an inorganic insulating film, a material having a thickness of 0.1 μm to 10 μm is used. SiO ₂ has a surface resistance value □ 10 ¹⁵ Ω, and TiO ₂ has a surface resistance value □ 10 ¹⁴ Ω.

  Next, a method for creating a height difference will be described. First, a resist material was applied onto the counterpart negative electrode, and the resist material was subjected to an exposure treatment through a previously prepared mask material. A portion of the resist material exposed by this exposure treatment was dissolved and removed with a stripping solution, thereby producing a conductive portion that was the counterpart negative electrode and an insulating portion that was the remainder of the resist material. Next, after depositing gold, platinum, copper, or silver on the exposed portion of the conductive portion of the counterpart negative electrode by plating, the resist material was removed to give a height difference of 1 μm to 100 μm to the surface of the counterpart negative electrode.

  In addition to the plating method, the surface of the counterpart negative electrode 5 can be made to have a height difference by depositing gold, platinum, copper, and silver using a resistance heating vacuum deposition method and then removing the resist portion. .

(solution)
As a solution used for the anodizing treatment, sulfuric acid, oxalic acid, phosphoric acid, and hydrofluoric acid aqueous solution 0.01 to 0.5 M (0.01 to 0.5 mol / dm ³ ) were prepared.

(Anodizing method)
□ Apply a resist material on platinum having a dimension of 500 μm, and then expose the other negative electrode with a platinum surface exposed to a dimension of 3 μm and □ 50 μm by exposure / development treatment. The distance from the substrate is in the range of 0.01 to 1 μm. I set it to be. Then, the voltage of 15V was applied between the other party negative electrode and the base | substrate, and the 1st anodic oxidation process was performed. As the substrate, an Al thin film formed on a graphite plate with a thickness of 10 μm was used. Thereafter, the electrode was moved 100 μm in the X direction and 100 μm in the Y direction, and a voltage of 40 V was applied to perform the second anodic oxidation treatment. As a result, an oxide film having upright pores having a diameter of 5 nm was obtained by the first anodic oxidation treatment, and an oxide film having upright pores having a diameter of 20 nm was obtained by the second anodic oxidation treatment. The solution temperature was 0 ° C.

  Further, conductive Si having a Ti or Zn film formed thereon was used, and the first and second anodic oxidation treatments were performed in an oxalic acid aqueous solution by applying the same voltage and operating distance as described above. In the case of the Ti film, the pore diameter in the region to which 15 V was applied was 2 nm, and the pore diameter in the region to which 40 V was applied was 50 nm. In the case of the Zn film, the pore diameter in the region to which 15 V was applied was 10 nm, and the pore diameter in the region to which 40 V was applied was 50 nm.

  Further, conductive Si was used as the substrate, and the first and second anodic oxidation treatments were performed in a hydrofluoric acid aqueous solution by applying the same voltage and operating distance as described above. The pore diameter in the region to which 15 V was applied was 8 nm, and the pore diameter in the region to which 40 V was applied was 30 nm.

Further, a region 1 and a region 2 each having □ 100 nm, □ 1 μm, □ 1 mm, and □ 1 cm are formed, and the counterpart negative electrode is exposed in each of □ 100 nm, □ 1 μm, □ 1 mm, and □ 1 cm in region 1. In each of □ 100 nm, □ 1 μm, □ 1 mm, and □ 1 cm in region 2, a counter negative electrode was prepared by depositing and exposing TiO ₂ . Incidentally, other than the portion mating anode and TiO ₂ is exposed covered with SiO _2. The film thicknesses of TiO ₂ and SiO ₂ were both 1 μm. Separately from this, with the surface of the counterpart negative electrode as a reference point, a counterpart negative electrode in which a hill with a height of 200 μm is formed in each of □ 100 nm, □ 1 μm, □ 1 mm, and □ 1 cm, and a height of 190 μm A negative electrode with a hill was also prepared.

After setting these counter negative electrode materials close to the range of 0.01 to 1 μm, a voltage of 40 V was applied. As a result, an oxide film having upright pores with a diameter of 20 nm is obtained in the region facing the portion where the counter negative electrode is exposed, and the upright pores having a diameter of 5 nm are obtained in the region facing the portion where TiO ₂ is exposed. An oxide film having the same was obtained. No pores were formed in the portion covered with SiO ₂ . In addition, in the case of the opposite negative electrode provided with a height difference, an oxide film having upright pores with a diameter of 20 nm was obtained in the region facing the part provided with the hill with a height of 200 μm, but the hill with a height of 190 μm was obtained. An oxide film having upright pores having a diameter of 10 nm was obtained in a region facing the provided portion, and a film having an upright pore structure was not obtained at the reference point.

(Pore diameter expansion processing)
After the anodizing treatment, the pore structure was immersed in a 2% by mass phosphoric acid aqueous solution to enlarge the pore diameter. The solution temperature was 25 ° C. By this treatment, the pore diameters, which were 5 nm and 20 nm immediately after the anodizing treatment, increased with the increase of the treatment time, and increased in the ranges of 5 nm to 40 nm and 20 nm to 50 nm, respectively.

(Luminescent characteristics)
An upright pore having a diameter of 2 nm by anodizing Al (5% Mn element doped) formed on quartz glass on which conductive Si and ITO films are formed, and an upright pore having a diameter of 10 nm An oxide film having Thereafter, the emission wavelength was measured by PL measurement. As a result, an emission wavelength near 570 nm and an emission wavelength near 650 nm could be confirmed in each of the region having pores with a diameter of 2 nm and the region having pores with a diameter of 10 nm.

  Similarly, Al (5% Cr element dope) was anodized to obtain an oxide film having upright pores having a diameter of 2 nm and upright pores having a diameter of 10 nm. Thereafter, the emission wavelength was measured by PL measurement. As a result, an emission wavelength near 590 nm and an emission wavelength near 690 nm could be confirmed in each of the region having pores with a diameter of 2 nm and the region having pores with a diameter of 10 nm.

(Separation performance)
As shown in FIGS. 9A and 9B, conductive Si, an Al film 11 formed on a graphite plate, or an Al plate 11 is anodized to have upright pores having a diameter of 2 nm. An oxide film 12 and an oxide film 13 having upright pores having a diameter of 10 nm were obtained. Thereafter, a channel 14 having a width of 1 mm and a depth of 0.5 mm was formed, and a solution containing molecular diameters of 2 nm and 10 nm was passed through the channel 14. As a result, molecules having molecular diameters of 2 nm and 10 nm could be separated in the membrane regions 12 and 13 each having an upright pore structure by one operation. FIG. 9B is a schematic cross-sectional view taken along line IX-IX in FIG.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The pore structure of the present invention and the method for producing the same can be applied particularly advantageously to a mold, a mask material, a light emitting element, and a filter material.

It is a conceptual diagram which shows the 1st example of the manufacturing method of the pore structure in one embodiment of this invention in process order. It is a conceptual diagram which shows the 2nd example of the manufacturing method of the pore structure in one embodiment of this invention. It is a figure which shows the method of giving the difference in electrical resistance to the other party negative electrode. It is a top view which shows the structure of the pore structure manufactured by the manufacturing method in one embodiment of this invention. It is a top view which shows the distance between pores. It is a figure which shows a mode that it transfers with a press using the pore structure in one embodiment of this invention. It is a figure which shows a mode that it transfers by impregnating and solidifying a liquid using the pore structure in one embodiment of this invention. It is a figure which shows a mode that it transfers by etching using the pore structure in one embodiment of this invention. It is the top view (a) which shows a mode that the pore structure body in one embodiment of this invention was used in order to investigate separation performance, and sectional drawing (b).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 DC power supply, 2 Container, 3 Electrolyte solution, 4,20 Base | substrate, 5 Opposite negative electrode, 6, 7 Insulating film, 11 Al film | membrane or Al plate formed on the graphite plate, 12, 13 Oxide film having pores, 14 Channel, 21a, 21b, 21c Same pore diameter region, 22a, 22b, 22c Pore, 25 Pore structure, 30, 40, 50 Material to be transferred.

Claims (10)

Comprising a membrane with upright pores formed on a flat or curved surface,
The pores formed in the film have a diameter of 0.1 nm to 100 nm,
The membrane has a plurality of regions, and pores having different diameters are formed in each of the plurality of regions,
A pore structure in which the area of each of the plurality of regions is in the range of 10 nm ^{2 to} 100 cm ² and the material of the film in each of the plurality of regions has an oxidized material.   The pore structure according to claim 1, wherein the pores formed in the film have a diameter of 0.1 nm or more and 50 nm or less.   The pore structure according to claim 1 or 2, wherein at least one element selected from the group IIB, group IIIB, group IVB, or transition metal is contained in at least one of the constituent elements of the film. body.   The pore structure according to any one of claims 1 to 3, wherein a distance between adjacent pores is 1 nm or more and 300 nm or less.   The pore structure according to any one of claims 1 to 4, wherein the pore structure is used as one of a mold and a mask material.   The pore structure according to claim 1, which is used as a light emitting element.   The pore structure according to any one of claims 1 to 4, wherein the pore structure is used as a filter functional material. A method for producing a pore structure in which pores are formed by anodizing an object to be treated in a solution with an electrode to be a negative electrode facing an object to be treated as an anode,
A method for producing a pore structure, wherein pores having different diameters are formed in each region of the object to be processed by changing the conditions of anodizing treatment in each region of the object to be processed.   By scanning the electrode relative to the object to be processed, the electrode is individually opposed to each of the plurality of regions of the object to be processed, and the anode is used under different conditions for each region of the object to be processed facing the electrode. The method for producing a pore structure according to claim 8, wherein oxidation treatment is performed.   The electrode is opposed to each of the plurality of regions of the object to be processed, and for each portion of the electrode facing each of the plurality of regions of the object to be processed, an electrical resistance and a distance from the object to be processed The method for producing a pore structure according to claim 8, wherein at least one of them is different.

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