JPWO2006038335A1 - Electrochemical deposition method, electrochemical deposition apparatus and microstructure - Google Patents

Abstract

Provided are an electrochemical deposition method, an electrochemical deposition apparatus, and a microstructure that determine the structure of a substance deposited on the surface of a working electrode. The anode 1 and the cathode 2 functioning as a working electrode are opposed to each other, and are disposed in a liquid tank 5 containing an electrolytic (acidic) solution (hereinafter referred to as a solution) 4 in which a plurality of substances are dissolved in an ionic state. A predetermined voltage is applied between the cathode 2. Further, the reference electrode 3 is disposed in the liquid tank 5 and the potential between the cathode 2 and the reference electrode 3 is measured. Since the solution 4 is considered to be a conductor, the potential V1 of the cathode 2 with respect to the solution 4 can be obtained. Furthermore, reaction inhibiting species are mixed in the liquid tank 5, and spontaneous electrochemical vibrations (here, current oscillations) are generated in the electrochemical deposition reaction of substances in the presence of the reaction inhibiting species. . By adjusting the cathode potential V1, the concentration of the substance in the solution, the type and concentration of the reaction-inhibiting species, the waveform of the electrochemical vibration is controlled, and the structure of the substance deposited on the surface of the working electrode is determined.

Description

  The present invention deposits a substance on the surface of a working electrode by applying a voltage or passing a current between a plurality of electrodes immersed in a solution in which a substance capable of electrochemical deposition such as metal is dissolved in an ionic state. The present invention relates to an electrochemical deposition method, an electrochemical deposition apparatus, and a microstructure in which one lattice has a scale of several tens to several hundreds of micrometers.

  Advances in microfabrication technologies have proposed nanoscale microdevices (nanodevices) in addition to improved integration. For example, nano-periodic structures such as metals, semiconductors, and conductive polymers are actively researched in various fields because various functions based on the periodic structures such as giant magnetoresistance, tunneling magnetoresistance, and photonic appear. It has been. Currently, as a method for producing a nano-periodic structure, a thin film forming method such as a vapor deposition method has been established. All of these are multi-step methods in which target substances are alternately stacked.

  However, since the conventional method as described above is multi-step, there is a problem that a decrease in productivity and an increase in cost are unavoidable. In addition, an increase in the configuration of an apparatus for manufacturing is unavoidable, and this also increases the cost.

  Therefore, as a technique for solving the above-described problem, a microfabrication technique by self-organization called structure formation by nonlinear chemical dynamics has been devised. This is a kind of bottom-up approach, and it is in an undeveloped stage, but it is expected as a technology that gives a big paradigm change to the conventional methods.

  There are two types of self-organization: static self-organization and dynamic self-organization. The structure formed by the former is a thermal equilibrium structure, that is, a static ordered structure. Force) and the principle of equilibrium thermodynamics. On the other hand, the structure formed by the latter is a pattern spontaneously formed in the flow of energy, that is, an ordered structure that appears in a nonequilibrium system, and has various structures in time and space. Dynamic self-organization has features such as the appearance of pull-in phenomenon, self-repair function, and long-range interaction that are not found in static self-organization, and if dynamic self-organization can be controlled. It becomes possible to manufacture a fine structure having a desired structure.

In Patent Document 1, a conductive support is immersed in an aqueous solution containing metal ions, the potential of the conductive support is vibrated using the conductive support as an electrode, and the metal layer and the metal oxidation are performed on the conductive support. A method of manufacturing a laminated film by alternately depositing physical layers is disclosed.
JP 2002-129374 A

  However, since the mechanism of dynamic self-assembly is not established and what is controlled is not established, self-organization can be controlled, so that a microstructure having a desired structure is manufactured. Was impossible. In other words, conventionally, a fine structure could be manufactured as a result of changing manufacturing conditions, but it was impossible to obtain a desired structure. In addition, since dynamic self-organization exists in the flow of energy, there is a problem that the structure disappears when the energy supplied from the outside is cut off.

  As a result of diligent research on dynamic self-organization in an electrochemical reaction system, the present inventor has found that when a microstructure is manufactured using electrochemical vibration (current vibration or potential vibration), The knowledge that the structure to be constructed is determined based on the waveform (period, amplitude, etc.) was obtained. The electrochemical reaction is easy to control, and even when the energy is cut off, the structure is accumulated as a history (precipitate), immobilizing and storing traces of dynamic spatiotemporal order The constructed structure is not lost. Further, the present inventor has found that the autocatalytic process can be controlled by controlling the waveform of the electrochemical vibration by the kind of the substance to be electrochemically deposited (for example, electrolytic deposition), the potential of the working electrode, and the current. Obtained.

  The present invention has been made with the above-described knowledge, and a voltage or current is applied between a plurality of electrodes immersed in a solution in which a substance capable of electrochemical deposition such as metal is dissolved in an ionic state. By flowing and controlling the potential or current of one electrode (referred to as working electrode) to the solution to generate electrochemical vibration, that is, current vibration or potential vibration, on the surface of the working electrode based on the waveform of the electrochemical vibration. An object is to provide an electrochemical deposition method for determining the structure of a deposited material.

  The present invention also provides an electrochemical method for controlling electrochemical oscillation by mixing a reaction-inhibiting species and causing an autocatalytic process by coupling a negative differential resistance induced by the reaction-inhibiting species with a potential drop in a solution. The purpose is to provide an effective precipitation method.

  In addition, the present invention controls the potential or current of the working electrode where electrochemical oscillation occurs by adjusting the concentration of the reaction-inhibiting species, and determines the structure of the substance deposited on the surface of the working electrode. The purpose is to provide a method.

  In addition, the present invention uses a cationic surfactant having a carbon chain of 10 or more as a reaction-inhibiting species, and adjusts the carbon chain, thereby controlling the potential or current at which electrochemical vibrations occur and depositing on the surface of the working electrode. It is an object of the present invention to provide an electrochemical deposition method for determining the structure of a material to be produced.

  Another object of the present invention is to provide an electrochemical deposition method that determines the structure of the substance deposited on the surface of the working electrode by controlling the waveform of the electrochemical vibration by adjusting the concentration of the substance.

  The present invention also provides an electrochemical deposition method for determining the composition ratio of a structure composed of a plurality of substances by controlling the waveform of electrochemical vibration when a plurality of substances are dissolved in a solution in an ionic state. With the goal.

  In the present invention, when the structure of the substance determined based on the waveform of the electrochemical vibration is a multilayer structure, the thickness of each layer of the multilayer structure and / or the composition ratio of each layer is controlled by controlling the waveform of the electrochemical vibration. It is an object to provide an electrochemical deposition method for determining.

  In addition, the present invention controls the surface of the working electrode based on the waveform of the electrochemical vibration by controlling the potential or current of the working electrode so that the electrochemical deposition advances to diffusion control, thereby generating the electrochemical vibration. It is an object of the present invention to provide an electrochemical deposition method for determining the structure of a substance deposited on a substrate.

  Further, the present invention detects the upper end potential or the lower end potential for each oscillation of the electrochemical vibration, and controls the current of the working electrode based on the detected fluctuation of the upper end potential or the lower end potential, so that the current density gradually decreases. It is an object of the present invention to provide an electrochemical deposition method and an electrochemical deposition apparatus capable of preventing the spontaneous vibration from stopping from the region where the spontaneous vibration occurs and stopping.

  In addition, by controlling the effective current density of the working electrode with respect to the solution to be substantially constant, the present invention makes the shape of the fine structure grown on the surface of the working electrode constant and has excellent uniformity. An object is to provide an electrochemical deposition method capable of obtaining a fine lattice structure.

  Further, the present invention has a configuration in which the current of the working electrode is controlled so that the current density at which spontaneous vibration occurs is generated, so that the current density gradually decreases and the spontaneous vibration is out of the region where the spontaneous vibration occurs. The purpose of the present invention is to provide an electrochemical deposition apparatus capable of continuing the spontaneous vibration without stopping.

  Further, the present invention uses a substance deposited by each of the electrochemical deposition methods described above as a three-dimensional basic skeleton, and deposits another substance on the surface of the substance, for example, a crystallographically stable surface is exposed. Another object of the present invention is to provide a microstructure that can be an electrode having a very high surface area with high strength.

  Another object of the present invention is to provide a microstructure having a porous structure formed by polymerizing another substance on the surface of the substance deposited by each of the electrochemical deposition methods described above and removing the deposited substance. And

  In the electrochemical deposition method according to the first invention, a voltage is applied or a current is passed between a plurality of electrodes immersed in a solution in which a substance capable of electrochemical deposition is dissolved in an ionic state, and the substance is applied to the surface of the working electrode. In the electrochemical deposition method for depositing, the potential or current of the working electrode with respect to the solution is controlled to generate electrochemical vibration, and the structure of the substance is determined based on the waveform of the electrochemical vibration. It is characterized by.

  In the present invention, a plurality of electrodes are immersed in a solution in which a substance (metal, semiconductor, conductive polymer, etc.) capable of electrochemical deposition is dissolved in an ionic state, and a voltage is applied between the plurality of electrodes or a current is applied. The dissolved substance is electrochemically deposited on the surface of one electrode (working electrode) of the plurality of electrodes. During electrochemical deposition, spontaneous electrochemical oscillation is generated by controlling the potential or current of the working electrode with respect to the solution. By controlling the potential or current of the working electrode, the waveform (for example, period) of the electrochemical vibration can be controlled, so that the structure of the substance deposited on the surface of the working electrode can be changed according to the waveform of the electrochemical vibration. Can be determined. Since the structure is self-assembled by the self-organized vibration phenomenon, the structure to be constructed is sequentially laminated to reflect the history of the vibration phenomenon. Therefore, since the structure is accumulated as a history and the trace of the dynamic spatiotemporal order can be fixed and stored, the constructed structure will not be lost.

  The electrochemical deposition method according to the second invention is the method according to the first invention, wherein a reaction inhibiting species is mixed in the solution, and the reaction inhibiting species is attached to the surface of the working electrode and not attached. Are generated alternately and by controlling the potential or current of the working electrode at which the electrochemical oscillation occurs.

  In the present invention, by mixing a reaction-inhibiting species into a solution, an autocatalytic process is caused by coupling between a negative differential resistance induced by the reaction-inhibiting species and a potential drop in the solution, that is, reaction inhibition. The state where the seed is attached to the surface of the working electrode and the state where the seed is not attached are spontaneously and alternately generated to control the potential or current of the working electrode where the electrochemical oscillation occurs. This reaction-inhibiting species can be mixed as appropriate depending on the chemical reaction system, and the potential or current region of the working electrode where electrochemical vibration occurs can be adjusted.

  The electrochemical deposition method according to a third aspect of the invention is characterized in that, in the second aspect of the invention, the potential or current of the working electrode in which the electrochemical oscillation occurs is controlled by adjusting the concentration of the reaction-inhibiting species. .

  In the present invention, by adjusting the concentration of the reaction-inhibiting species, it is possible to control the potential or current of the working electrode where electrochemical oscillation occurs. For example, in the current oscillation that is one form of electrochemical oscillation, the potential of the negative differential resistance (the potential of the working electrode at which the current flowing through the working electrode rapidly decreases) is adjusted to the concentration of the reaction-inhibiting species mixed in the solution. Therefore, it can be moved to the positive side or the negative side. Specifically, the potential at which current oscillation occurs can be shifted to the positive side by increasing the concentration of the reaction-inhibiting species. Since current oscillation occurs at the potential of negative differential resistance, when the same reaction-inhibiting species is used, the potential at which current oscillation occurs can be controlled by adjusting the concentration of the reaction-inhibiting species. The structure of the substance deposited on the surface can be determined.

  In the electrochemical deposition method according to a fourth aspect of the present invention, in the second aspect or the third aspect, the reaction-inhibiting species is a cationic surfactant having 10 or more carbon chains, and the carbon chain is adjusted by adjusting the carbon chain, It is characterized by controlling the potential or current of the working electrode in which electrochemical vibration occurs.

  In the present invention, when a cationic surfactant having a carbon chain of 10 or more is used as a reaction-inhibiting species, the potential or current of the working electrode at which electrochemical oscillation occurs is controlled by adjusting the carbon chain. Can do. For example, the potential of the negative differential resistance can be moved to the positive side or the negative side by adjusting the carbon chain. Specifically, the potential at which current oscillation occurs can be shifted to the positive side by lengthening the carbon chain. Therefore, when the same series of reaction inhibiting species is used, the potential at which current oscillation occurs can be controlled by adjusting the carbon chain, and the structure of the substance deposited on the surface of the working electrode can be determined.

  An electrochemical deposition method according to a fifth invention is characterized in that, in any one of the first to fourth inventions, the waveform of the electrochemical vibration is controlled by adjusting the concentration of the substance.

  In the present invention, the potential or current of the working electrode can be controlled by adjusting the concentration of the substance contained in the solution, that is, the waveform of the electrochemical vibration can be controlled. Can be determined.

  The electrochemical deposition method according to a sixth aspect of the present invention is the method according to any one of the first to fifth aspects, wherein a plurality of substances are dissolved in an ionic state in the solution, and the waveform of the electrochemical vibration is controlled. And determining a composition ratio of the structure composed of the plurality of substances.

  In the present invention, when a plurality of substances are dissolved in a solution in an ionic state, the composition ratio of the structure composed of the plurality of substances can be determined by controlling the waveform of the electrochemical vibration. For example, when depositing a structure composed of a plurality of substances, each substance has a different deposition amount with respect to the potential of the working electrode, depending on the degree of ionization tendency. In addition, if the potential of the working electrode is controlled, the waveform of the electrochemical vibration can be controlled. Therefore, the deposition amount of each substance can be controlled to determine (control) the composition ratio of the structure. For example, when the substance is a metal, if the potential of the working electrode is lowered (a more negative potential), the deposition current increases, that is, the amount of precipitation increases, but the degree of ionization tendency of the metal increases. Since the ratio of the precipitation amount with respect to the potential varies depending on the difference, the composition ratio can be changed.

  An electrochemical deposition method according to a seventh invention is characterized in that, in any one of the first invention to the sixth invention, the structure of the substance determined based on the waveform of the electrochemical vibration is a multilayer structure. .

  In the present invention, a substance having a multilayer structure can be deposited on the surface of the working electrode by the above-described electrochemical deposition method.

  The electrochemical deposition method according to an eighth aspect of the invention is characterized in that, in the seventh aspect of the invention, the waveform of the electrochemical vibration is controlled to determine the film thickness and / or composition ratio of each layer of the multilayer structure. .

  In the present invention, for example, by adjusting the concentration of the substance contained in the solution, the potential or current of the working electrode can be controlled, that is, the waveform of the electrochemical vibration can be controlled. Can be controlled. In the case of generating a multilayer structure having a plurality of substances, the amount of precipitation of each substance can be adjusted, so that the film thickness of each layer and / or the composition ratio of each layer can be determined. Specifically, the film thickness of each layer can be determined by adjusting the concentration of each substance while maintaining the concentration ratio of each substance constant.

  The electrochemical deposition method according to a ninth invention is characterized in that, in any one of the first to eighth inventions, the substance is a metal.

  In the present invention, the metal can be deposited on the surface of the working electrode by the electrochemical deposition method described above.

  The electrochemical deposition method according to a tenth aspect of the invention is characterized in that, in the first aspect of the invention, the potential or current of the working electrode is controlled so that the electrochemical deposition is governed by diffusion to generate electrochemical vibrations. And

  In the present invention, the electrochemical oscillation is generated by controlling the potential or current of the working electrode so that the electrochemical deposition advances to diffusion control. Electrochemical phenomena occur due to the combination of autocatalytic crystal growth in a specific orientation and autocatalytic surface deactivation on the thermodynamically stable surface, so the surface of the working electrode has a history of electrochemical vibrations. Reflecting, a fine regular structure grown in the vertical direction of the working electrode is formed. Therefore, since the structure is accumulated as a history and the trace of the dynamic spatiotemporal order can be fixed and stored, the constructed structure will not be lost.

  The electrochemical deposition method according to an eleventh aspect of the present invention is the method according to the tenth aspect, wherein an upper end potential or a lower end potential for each oscillation of the electrochemical vibration is detected, and the working electrode is It is characterized by controlling the current.

  In the present invention, the upper end potential or the lower end potential for each oscillation of the electrochemical vibration is detected, and the current of the working electrode is controlled based on the detected fluctuation of the upper end potential or the lower end potential. The vibration phenomenon starts spontaneous vibration at the boundary of the current density that is a threshold value that shifts from the reaction-controlled process to the diffusion-controlled process. By the way, since the microstructure grows on the surface of the working electrode, the effective electrode area of the working electrode gradually increases, the current density gradually decreases, and the spontaneous vibration is generated outside the region where the spontaneous vibration occurs. It will stop. Therefore, spontaneous vibration can be continued by controlling the current of the working electrode.

  The electrochemical deposition method according to a twelfth aspect of the invention is characterized in that, in the eleventh aspect of the invention, the effective current density of the working electrode with respect to the solution is controlled to be substantially constant.

  In the present invention, by controlling the effective current density of the working electrode with respect to the solution to be substantially constant, the shape of the microstructure (for example, the lattice spacing) that grows on the surface of the working electrode becomes constant. Thus, a fine lattice structure with excellent uniformity can be obtained.

  The electrochemical deposition method according to a thirteenth aspect of the invention is characterized in that, in any of the tenth to twelfth aspects of the invention, the waveform of the electrochemical vibration is controlled by adjusting the concentration of the substance.

  In the present invention, the potential or current of the working electrode can be controlled by adjusting the concentration of the substance contained in the solution, that is, the waveform of the electrochemical vibration can be controlled. Can be determined. For example, the individual structure of the periodic structure of the substance can be increased by increasing the ion concentration of the substance.

  An electrochemical deposition apparatus according to a fourteenth aspect of the present invention is a method in which an electric current is caused to flow between a plurality of electrodes immersed in a solution in which a substance capable of electrochemical deposition is dissolved in an ionic state, thereby generating electrochemical vibrations. An electrochemical deposition apparatus for depositing the substance on the substrate, comprising: a detecting means for detecting an upper end potential or a lower end potential for each oscillation of the electrochemical vibration; and an upper end potential or a lower end potential detected by the detecting means. And control means for controlling the current of the working electrode with respect to the solution.

  In the present invention, a plurality of electrodes are immersed in a solution in which a substance capable of electrochemical deposition (metal, semiconductor, conductive polymer, etc.) is dissolved in an ionic state, and the detection means is provided for each vibration of the electrochemical vibration. The upper end potential or the lower end potential is detected, and the control means controls the current of the working electrode with respect to the solution based on the detected upper end potential or lower end potential. By causing a current to flow between the plurality of electrodes, a spontaneous electrochemical vibration is generated, and the dissolved substance is electrochemically deposited on the surface of one of the plurality of electrodes (working electrode). The By controlling the current flowing through the working electrode, the structure of the deposited substance can be controlled.

  An electrochemical deposition apparatus according to a fifteenth aspect of the invention is characterized in that, in the fourteenth aspect, the control means controls the current density to generate spontaneous vibration.

  In the present invention, by controlling the current of the working electrode so as to obtain a current density at which spontaneous vibrations occur, the current density gradually decreases, and the spontaneous vibrations deviate from the region where the spontaneous vibrations occur. Spontaneous vibration can be continued without stopping.

  The microstructure according to the sixteenth invention is characterized in that a substance deposited by each electrochemical deposition method described above is used as a three-dimensional basic skeleton, and another substance is deposited on the surface of the substance.

  In the present invention, a fine structure (for example, a fine lattice structure) is used as a three-dimensional basic skeleton (template), and another substance (conductor) such as platinum is deposited on the surface of the fine structure. It can be an electrode having a high strength and a very large surface area. It also has the advantage that a crystallographically stable surface is exposed.

  In the microstructure according to the seventeenth invention, a porous structure is formed by polymerizing another substance on the surface of the substance deposited by each of the electrochemical deposition methods described above and removing the deposited substance. It is characterized by that.

  In the present invention, it is possible to realize a fine structure in which the fine structure is a blank pattern using the fine structure (for example, a fine lattice structure) as a three-dimensional template.

  According to the present invention, a fine regular structure is self-assembled vertically from the substrate by a self-organized vibration phenomenon. In addition, the structures to be constructed are sequentially stacked to reflect the history of vibration phenomena. In the present invention, since the electrochemical vibration phenomenon itself is controlled, the resulting regular structure can be controlled. Furthermore, from a simple periodic structure, a more complicated three-dimensional regular structure and various fine lattice structures can be constructed on the entire surface of the electrode in one step and at a low cost. Furthermore, by controlling the current of the working electrode so as to obtain a current density at which spontaneous vibrations occur, the current density gradually decreases, and the spontaneous vibrations stop from the region where the spontaneous vibrations occur. In other words, the spontaneous vibration can be continued, and a metal fine lattice aggregate having a millimeter to centimeter scale can be obtained. If the obtained regular structure itself is used as a template, a three-dimensional regular structure such as a metal, a semiconductor, and a conductive polymer can be constructed. Furthermore, in principle, it can be applied to an electrochemical deposition reaction of a desired substance by appropriately selecting a reaction-inhibiting species, and therefore, application to various functional material formation is expected. Furthermore, since the configuration of the apparatus therefor is extremely simple, there are excellent effects such as that a predetermined microstructure can be manufactured at a very low cost.

It is explanatory drawing for demonstrating the electrochemical deposition method which concerns on Embodiment 1 of this invention. It is a graph which shows an electric current oscillation. It is explanatory drawing for demonstrating the evaluation method of a thin film. It is an electron micrograph and an Auger spectroscopy result which show the evaluation result of the multilayer film formed by the electrochemical deposition method concerning Embodiment 1 of this invention. It is a graph which shows the precipitation current of Cu and Sn with respect to the electric potential of a working electrode. It is a graph which shows a response | compatibility with the waveform of an electric vibration, and the composition ratio of a precipitate. Is a graph showing the deposition current with respect to the potential of the working electrode in the case of using the _{C X H 2X-1 N (} CH 3) 3 Cl. It is a graph which shows the precipitation current with respect to the electric potential of a working electrode at the time of using C12TAC. It is explanatory drawing for demonstrating the electrochemical deposition method which concerns on Embodiment 2 of this invention. It is a graph which shows potential oscillation. It is an electron micrograph which shows an example of the microstructure formed by the electrochemical deposition method concerning Embodiment 2 of this invention. It is explanatory drawing for demonstrating the periodic structural change synchronized with the electric potential vibration of Sn. It is explanatory drawing for demonstrating the periodic structural change synchronized with the electric potential vibration of Sn. It is a graph which shows the potential oscillation in Sn. It is an electron micrograph which shows the fine structure constructed | assembled by changing the electric current value of a working electrode. It is a graph which shows the electric potential oscillation in Zn. It is an electron micrograph which shows the fine structure constructed | assembled when the ion concentration of Zn is changed. It is a graph which shows the relationship between an electric potential and a current density. It is a graph which shows a time change of potential oscillation. FIG. 20 is an electron micrograph at points A and B in FIG. It is explanatory drawing for demonstrating the structure of the electrochemical deposition apparatus which concerns on Embodiment 3 of this invention. It is explanatory drawing for demonstrating control of the electric current value by a control part. It is a graph which shows an example of control of the electric current value by a control part. It is an optical microscope photograph which shows an example of the microstructure formed using the electrochemical deposition apparatus which concerns on Embodiment 3 of this invention.

Explanation of symbols

1,11 Anode 2,12 Cathode (working electrode)
3,13 Reference electrode 4,14 Solution 5,15 Liquid tank

  Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof.

(Embodiment 1)
FIG. 1 is an explanatory diagram for explaining an electrochemical deposition method according to Embodiment 1 of the present invention. In this example, the case of controlling current vibration as one form of electrochemical vibration will be described.
In the figure, an electrolytic (acidic) solution (hereinafter referred to as a solution) in which a plurality of substances (herein referred to as Cu and Sn) are dissolved in an ionic state with an anode 1 and a cathode 2 which are conductive metal substrates facing each other. 4 is placed in a liquid tank 5 containing a predetermined voltage, and a predetermined voltage is applied between the anode 1 and the cathode 2. In addition to the two electrodes 1 and 2 described above, the reference electrode 3 is disposed in the liquid tank 5 and the potential between the cathode 2 and the reference electrode 3 is measured. Since the solution 4 is considered to be a conductor, the potential V1 of the cathode 2 with respect to the solution 4 can be obtained. Furthermore, reaction inhibiting species are mixed in the solution 4, and spontaneous electrochemical oscillation (here, current oscillation) is generated in the electrochemical deposition reaction of Cu and Sn in the presence of the reaction inhibiting species. . The reaction-inhibiting species is, for example, a cationic surfactant, such as Amiet-320 (Chemical Formula 1), C _X H _2X-1 N (CH ₃ ) ₃ Cl (Chemical Formula 2), Triton X-100 (Chemical Formula 3), and the like. Can be used. Incidentally, it is preferable to incorporation of citric acid to the solution 4 as a smoothing agent, in this example, 0.15 M of CuSO _4, SnSO ₄ of 0.15 M) 0.6M of _H 2 _SO 4, citric acid 0.5M , And solution 4 mixed with 0.5 mM Amiet-320 was used.

  By mixing the reaction inhibiting species into the solution 4, an autocatalytic process occurs due to the coupling between the negative differential resistance induced by the reaction inhibiting species and the potential drop in the solution, and the potential V1 of the cathode 2 is within a predetermined range. In this case, minute fluctuations (concentration, temperature, etc.) are amplified by the autocatalytic process, and current oscillation that becomes macroscopic and periodic oscillation as shown in FIG. 2 appears.

  More specifically, since the solution 4 is considered to be a conductor, a strong electric field is applied to each ion on the surface of the cathode 2 and dehydration occurs due to the influence, and each ion receives an electron from the cathode 2 and becomes an adsorbed atom. The adsorbed atoms diffuse on the cathode surface, reach the formation point of the crystal lattice, and a crystal is formed. Attachment and desorption of reaction-inhibiting species to the cathode 2 occur alternately and spontaneously, and a vibration phenomenon appears with the attachment and desorption of reaction-inhibiting species. In this example, the cathode 2 functions as a working electrode, and a thin film excellent in smoothness composed of Cu and Sn is deposited on the surface of the cathode 2 on the surface of the cathode 2 on the basis of the manifested vibration phenomenon waveform. The smoothness is caused by mixing citric acid, and when the citric acid is not mixed, irregularities remain on the film surface.

  Next, the grown thin film was evaluated. FIG. 3 is an explanatory diagram for explaining a thin film evaluation method. First, while rotating the sample 20 on which the thin film 21 is grown, the thin film surface is subjected to Ar etching treatment (FIG. 3A), and a mortar-shaped hole is formed in the thin film 21 (FIG. 3B). The thin film 21 processed in this way was observed from the upper surface with an electron microscope, and the presence of concentric contrast (brightness ratio) was confirmed as shown in FIG. That is, it was confirmed that the grown thin film had a multilayer structure. Furthermore, in order to evaluate the composition ratio of the thin film (multilayer film), the side surface of the multilayer film was analyzed by scanning Auger spectroscopy. As a result, the composition ratio changed periodically as shown in FIG. Confirmed that.

  Since the multilayer film grows on the surface of the cathode 2, for example, by making the shape of the cathode 2 cylindrical, a multilayer film having excellent smoothness can be formed inside the cylinder. The electrochemical deposition method can grow precipitates on the surface without depending on the shape of the electrode, so a multilayer film with excellent smoothness can be formed on the surface of any shape of electrode. can do. In other words, a multilayer film having a desired shape can be formed on the surface of the electrode by applying the electrochemical deposition method of the present invention using an electrode previously processed into a desired shape.

  The multilayer film is a thin film (an alloy of Cu and Sn) deposited by the occurrence of current oscillation. In the present invention, the composition ratio, film thickness, and number of layers (number of layers) of this multilayer film are as follows. Control as follows.

<1, cathode potential>
The potential of the cathode (working electrode) where current oscillation occurs has a range, and by adjusting the potential of the working electrode, the waveform of current oscillation is controlled to adjust the composition ratio of the multilayer film and the film thickness of each layer. be able to. In other words, the potential of the working electrode may be adjusted to obtain a multilayer film having a desired composition ratio. The potential of the working electrode can be set to a desired value by changing the voltage applied between the anode 1 and the cathode 2.

FIG. 5 is a graph showing the deposition current of Cu and Sn with respect to the potential of the working electrode. In Cu and Sn, if the potential of the working electrode is lowered (when the potential is made more negative), the deposition current increases. However, Sn causes a deposition current from a more negative potential than Cu. Therefore, if it is set so as to generate current oscillation in a state where the potential of the working electrode is high, the precipitation amount of Sn can be reduced as compared with the precipitation amount of Cu, that is, the composition ratio of Cu (Cu / (Cu + Sn)). ) Can be increased. Conversely, the Cu composition ratio can be reduced by setting so as to cause current oscillation in a state where the potential of the working electrode is low. In other words, the composition ratio of the precipitate can be controlled by adjusting the potential of the cathode according to the difference in the degree of ionization tendency of the substances contained in the solution. For example, a multilayer film in which Cu ₂ Sn ₈ / Cu ₇ Sn ₃ is laminated as a single unit structure can be formed.

  In addition, by adjusting the potential of the working electrode, the thickness of each layer can be adjusted by controlling the waveform (for example, the period) of current oscillation. For example, the film thickness of each layer can be increased by lowering the potential of the working electrode, and conversely, the film thickness can be decreased by increasing and decreasing the potential.

<2. Concentration of substances in solution>
Since the deposition current can be adjusted by adjusting the concentration of each substance contained in the solution, the composition ratio can be determined (controlled) by adjusting the deposition amount of each substance. For example, the Cu composition ratio can be increased by increasing the Cu concentration.

Further, the film thickness of each layer can be adjusted by adjusting the concentrations of Cu and Sn while maintaining the concentration ratio of Sn and Cu constant. Figure 6 is a graph showing the correspondence between the composition ratio of the waveform and precipitates electric oscillation, FIG. (A), (b) is, 0.15 M concentration of CuSO ₄ and SnSO _4, respectively, in 0.10M Indicates a case. By reducing the concentration, the period of vibration can be shortened, and a multilayer film corresponding to the period of vibration can be deposited. For example, in this example, when the concentration is 0.15M, the thickness of each layer is 90 nm, and when it is 0.10M, the thickness of each layer is 38 nm.

<3. Kind and concentration of reaction inhibiting species>
When reaction-inhibiting species are attached to one location of the substrate due to fluctuations, the autocatalytic function of the reaction-inhibiting species spreads over the entire surface of the cathode in phase, so that precipitates are deposited on the entire surface of the cathode. The potential of the cathode at which the reaction-inhibiting species is attached is determined by the type and concentration of the reaction-inhibiting species. Can be controlled.

When C _X H _2X-1 N (CH ₃ ) ₃ Cl is used, it functions as a reaction-inhibiting species if the carbon chain is 10 (C10) or more, and the composition parameter X is 10 (C10TAC), 12 (C12TAC), and 16 (C16TAC) was confirmed to function as a reaction-inhibiting species.

0.15 M CuSO ₄ , 0.15 M SnSO ₄ , 0.5 M H ₂ SO ₄ ) and 0.5 M citric acid, C _X H _2X-1 N (CH ₃ ) ₃ with different 5 mM carbon chains Using the solution 4 mixed with Cl, the relationship between the type of reaction-inhibiting species and the potential at which current oscillation occurs was evaluated.
FIG. 7 is a graph showing the deposition current with respect to the potential of the working electrode when C _X H _2X-1 N (CH ₃ ) ₃ Cl is used. FIG. 7A shows C10TAC, and FIG. 7B shows C12TAC. (C) shows the case where C16TAC is mixed into the solution as a reaction-inhibiting species. Since current oscillation occurs at negative differential resistance potential, when using the same series of reaction-inhibiting species, the potential at which current oscillation occurs can be shifted to the positive side by using a reaction-inhibiting species with a long carbon chain. Can do. Therefore, by adjusting the carbon chain of the reaction-inhibiting species, the potential at which current vibration occurs can be controlled, that is, the waveform of the current vibration can be controlled, so that a multilayer film having a structure corresponding to the current vibration can be formed.

Using a solution 4 in which 0.15M CuSO ₄ , 0.15M SnSO ₄ , 0.25M H ₂ SO ₄ , and 0.5M citric acid were mixed with C12TAC at different concentrations, The relationship between the concentration and the potential at which current oscillation occurs was evaluated.
FIG. 8 is a graph showing the deposition current with respect to the working electrode potential when C12TAC is used. FIG. 8A shows the concentration of C12TAC at 2 mM, FIG. 8B shows the concentration of C12TAC at 3 mM, and FIG. ) Shows the case where the concentration of C12TAC is 4 mM. Since current oscillation occurs at the potential of the negative differential resistance, when the same reaction-inhibiting species is used, the potential at which current oscillation occurs can be shifted to the positive side by increasing its concentration. Therefore, by adjusting the concentration of the reaction-inhibiting species, the potential at which current oscillation occurs can be controlled, that is, the waveform of current oscillation can be controlled, so that a multilayer film having a structure corresponding to the current oscillation can be formed.

As described above in detail, according to the electrochemical deposition method according to Embodiment 1, a multilayer film can be formed on the entire surface of the working electrode in one step and at a low cost. In principle, by selecting reaction-inhibiting species as appropriate, it can be applied not only to metals but also to electrochemical deposition reactions such as semiconductors (eg Cu ₂ O) and conductive polymers (eg polyaniline). Application to material formation is expected. In addition, since the configuration of the apparatus for that purpose is extremely simple, a predetermined microstructure can be manufactured at an extremely low cost.

In this embodiment, the case where a Cu / Sn alloy is produced from a mixed solution of Cu / Sn has been described. However, the material is not limited, and phenanthrene (C ₁₄ H) acting as a reaction inhibiting species is not limited. _The multilayer film is also used in the electrochemical deposition reaction of Cu in the solution mixed with ₁₀ ) and the electrochemical deposition reaction of Ni in the solution mixed with hypophosphorous acid (H ₂ PO (OH)). It is effective for a reaction system that is formed and generates current oscillation. Therefore, a high-quality multilayer structure can be easily constructed from a desired material. For example, a device having a function based on a multilayer structure such as a giant magnetoresistance and a tunnel magnetoresistance can be manufactured easily and at low cost.

  In this embodiment, the current oscillation is described as one form of the electrochemical oscillation. However, the same applies to the potential oscillation in which the potential of the working electrode oscillates, and the oscillation phenomenon is generated by controlling the current of the working electrode. It goes without saying that it may be done.

(Embodiment 2)
In the first embodiment, a reaction inhibiting species is mixed with a solution, and a vibration phenomenon is caused by coupling between a negative differential resistance induced by the reaction inhibiting species and a potential drop in the solution. The potential or current of the working electrode may be controlled so that the deposited substance on the surface of the working electrode proceeds to the diffusion control of the material, and this is the second embodiment. Hereinafter, a method for controlling the potential oscillation to form the lattice structure on the surface of the working electrode will be described.

FIG. 9 is an explanatory diagram for explaining an electrochemical deposition method according to Embodiment 2 of the present invention. Note that in this example, the case of controlling potential vibration as one form of electrochemical vibration will be described.
In the figure, an electrolytic solution (hereinafter referred to as a solution) 14 in which a substance (herein, a metal such as Sn or Zn) is dissolved in an ionic state with an anode 11 and a cathode 12 which are conductive metal substrates facing each other. A predetermined current is passed between the cathode 12 and the anode 11 in the liquid tank 15. That is, a constant current source is connected between the cathode 12 and the anode 11. In addition, the output current value by a constant current source shall be set suitably. In addition to the two electrodes 11 and 12 described above, the reference electrode 13 is disposed in the liquid tank 15 and the potential between the reference electrode 13 and the cathode 12 is measured. Since the solution 14 is considered to be a conductor, the potential V2 of the cathode 12 with respect to the solution 14 can be obtained. In the electrochemical deposition reaction of a substance, the current is controlled so as to proceed to diffusion control under the diffusion-controlled condition of the substance, thereby generating a spontaneous electrochemical vibration (here, a potential vibration). In this example, a solution 14 in which 0.2 M Sn ²⁺ and 4 M NaOH were mixed was used.

  By controlling the current so as to proceed to the diffusion control, a self-catalytic process occurs, and when the current value between the cathode 12 and the anode 11 is within a predetermined range, a minute fluctuation is amplified by the auto-catalytic process. As shown in FIG. 10, a potential oscillation that is a macroscopic and periodic oscillation appears.

  Since the vibration phenomenon occurs due to a balance between autocatalytic crystal growth in a specific orientation and autocatalytic surface deactivation in a thermodynamically stable plane, a potential oscillation is generated on the surface of the cathode 12 functioning as a working electrode. Reflecting this history, a fine regular structure grown in the vertical direction of the working electrode is formed. When the material is Sn or Zn, as shown in FIGS. 11A and 11B, a lattice structure and a structure in which hexagonal plates are overlapped are constructed. Of course, the type of substance is not limited. For example, in the case of Pb, a three-dimensionally stretched fine network structure is constructed. Thus, the structure to be deposited depends on the crystal structure of the substance to be deposited.

  In order to evaluate how the waveform of the potential oscillation is reflected in the lattice structure, the cathode 12 (working electrode) is pulled up from the solution 14 at each potential of the potential oscillation, and the surface of the working electrode is scanned with an electron microscope and an optical microscope. And observed.

FIGS. 12 and 13 are explanatory diagrams for explaining the periodic structural change synchronized with the potential oscillation of Sn. FIG. 12A shows the waveform of the potential oscillation of Sn, and FIG. 12B shows the crystal of Sn. FIGS. 13A, 13B, and 13C show an electron microscope (SEM) photograph of the cathode surface at each point of potentials A, B, and C in FIG. OM) A photograph and a schematic diagram. The constant current source was set so that a current density of −36 mA / cm ² would flow between the cathode 12 and the anode 11.

  At the negative end of the potential oscillation (potential A in FIG. 12 (a)), angular Sn crystals are observed, each one of which is the (110) plane or (011) plane which is a thermodynamically stable orientation plane. It was observed that was exposed (FIG. 13A). When the potential shifted from negative to positive (FIG. 12 (a) potential B), it was observed that needle-like Sn was deposited in the <101> direction from the corners of the angular Sn crystal. (FIG. 13B). In addition, at the positive end potential (FIG. 12 (a) potential C), it was observed that the tip of the needle-like Sn again exposed the thermodynamically stable surface and started crystallization (FIG. 13). (C)). From this observation result, it was found that if the waveform of the potential oscillation can be controlled, the formed lattice structure can be formed into a desired shape.

Next, how to control the waveform of the potential oscillation will be described.
<1, current value of working electrode>
FIG. 14 is a graph showing potential oscillation in Sn, where the horizontal axis indicates the passage of time and the vertical axis indicates the potential. In the figure, a constant current of −12 mA is allowed to flow between the working electrode, that is, the cathode 12 and the anode 11 until 62 seconds, and a constant current of −20 mA is allowed to flow between the cathode 12 and the anode 11 after 62 seconds. Shows potential oscillation. It can be seen that by changing the current value, the waveform of the potential oscillation changes at 62 seconds as a boundary. The reaction is unstable until 42 seconds, indicating that the potential oscillation is unstable.

  Thus, the structure constructed by changing the current value of the working electrode can control the structural parameters of the formed lattice as shown in FIG. That is, when depositing Sn in this example, the lattice spacing can be changed by changing the current value. In this example, since the current value was changed during the crystal growth, it can be seen that the lattice spacing changed from the crystal C at the time when the current value was changed.

  In other words, the current value at which the potential oscillation occurs has a range, and by adjusting the current value, the waveform of the potential oscillation can be controlled to control the structural parameters of the structure to be formed.

<2. Concentration of substances in solution>
Using a solution 14 in which Zn ²⁺ and 4M NaOH having different concentrations were mixed, the relationship between the concentration of the substance and the waveform of potential oscillation was evaluated.
FIG. 16 is a graph showing potential oscillation in Zn, the horizontal axis shows the passage of time, and FIGS. 16A, 16B, and 10C show the Zn ion concentrations of 0.1M and 0.2M, respectively. , 0.5 M, respectively. By increasing the Zn ion concentration, the oscillation period can be lengthened. FIG. 17 is an electron micrograph showing a fine structure constructed when the ion concentration of Zn is changed. (A), (b), and (c) show the cases where the ion concentrations are 0.1 M, 0.2 M, and 0.5 M, respectively, and the size of the formed hexagonal plate is changed to the ion concentration. It can be seen that it can be increased accordingly.

  In other words, the waveform of the potential oscillation can be controlled also by adjusting the concentration of the substance contained in the solution, so that the structural parameters of the structure to be formed can be controlled as described above.

  As described above in detail, according to the electrochemical deposition method according to the second embodiment, it is possible to form a microstructure unique to the deposited material on the entire surface of the working electrode in one step and at a low cost. . In addition, since the configuration of the apparatus for that purpose is extremely simple, a predetermined microstructure can be manufactured at an extremely low cost.

  In this embodiment, the potential oscillation is described as one form of the electrochemical oscillation. However, the same applies to the current oscillation in which the current of the working electrode oscillates, and the oscillation phenomenon is generated by controlling the potential of the working electrode. It goes without saying that it may be done.

By the way, as one form of electrochemical vibration, as shown in FIG. 18, the potential vibration starts to vibrate spontaneously with the current density as a boundary at the threshold value jdl (approximately −25 mA / cm ² ). In other words, when the current density is low, electrochemical vibration does not occur, and the threshold value jdl can be said to be a boundary that shifts from the reaction-controlled process to the diffusion-controlled process. In other words, in order to continue the potential oscillation, it is very important to control the current density and maintain the diffusion-controlled process.

  FIG. 19 is a graph showing changes in potential oscillation with time, with the horizontal axis representing the passage of time and the vertical axis representing the potential. FIG. 19A shows a case where a constant current is applied between the working electrode (that is, the cathode 12) and the anode 11, and the potential oscillation stops when approximately 250 seconds (approximately 75 times in terms of the number of oscillations) have elapsed. Resulting in. This is because a fine structure grows on the surface of the working electrode, so that the effective electrode area of the working electrode gradually increases, and the current density gradually decreases to deviate from the region where spontaneous vibration occurs. . Further, as shown in FIG. 20, since the current density is reduced every time the growth is repeated, the lattice spacing of the fine structure grown on the surface of the working electrode is gradually reduced, and the uniformity of the fine structure is impaired. . 20A and 20B are electron micrographs at points A and B in FIG. 19A, respectively.

  Accordingly, as shown in FIG. 19B, the current applied between the working electrode (that is, the cathode 12) and the anode 11 is controlled so as to cancel the effect of the increase in consideration of the effective increase in the electrode area. It is preferable to continue the spontaneous vibration (increase gradually) so that the effective current density does not change.

(Embodiment 3)
FIG. 21 is an explanatory diagram for explaining the configuration of an electrochemical deposition apparatus according to Embodiment 3 of the present invention. Note that in this example, the case of controlling potential vibration as one form of electrochemical vibration will be described.
In the electrochemical deposition apparatus according to Embodiment 3 of the present invention, an anode 11 and a cathode 12 which are conductive metal substrates are opposed to each other, and a substance (here, a metal such as Sn or Zn) is in an ionic state. A dissolved electrolytic solution (hereinafter referred to as “solution”) 14 is placed in a liquid tank 15, and current is passed between the cathode 12 and the anode 11. Further, in addition to the two electrodes 11 and 12 described above, the reference electrode 13 is disposed in the liquid tank 15, the potential between the reference electrode 13 and the cathode 12 is measured, and the upper end potential or lower end for each vibration of the electrochemical vibration. A detection unit 16 that detects the potential, and a control unit 10 that controls the current of the working electrode with respect to the solution based on the upper end potential or the lower end potential detected by the detection unit 16 are provided. Since the solution 14 is considered to be a conductor, the potential V2 of the cathode 12 with respect to the solution 14 is obtained, and the control unit 10 controls the current flowing between the cathode 12 and the anode 11 based on the potential V2. Specifically, a constant current source is connected between the cathode 12 and the anode 11, and the control unit 10 controls the output current value. Here, the upper end potential is an extreme value (maximum value) in the positive direction of vibration, and the lower end potential is an extreme value (minimum value) in the negative direction of vibration.

FIG. 22 is an explanatory diagram for explaining the control of the current value by the control unit.
FIG. 4A shows a potential waveform when potential oscillation occurs, where A is the nth vibration waveform, B is the (n + 1) th vibration waveform, and C is the (n + 2) th vibration waveform. As described above, since the fine structure grows on the working electrode by the potential vibration, the effective electrode area is increased, and the upper end potential and the lower end potential of the potential vibration are displaced in the negative direction for each vibration. Further, assuming that the solution resistance is R, a potential loss of I × R occurs when the current I flows according to Ohm's law. That is, as shown in FIG. 5B, in the growth process from the nth generation to the (n + 1) th generation, a potential loss corresponding to an increase in electrode area ΔA occurs. Since the current I is proportional to the area A, it can be expressed as I = k × A, and the increase in potential loss is (k × ΔA) × R. Here, the displacement amount ΔU of the upper end potential and the lower end potential (hereinafter referred to as the upper end potential) of the potential oscillation can be expressed by ΔU = (k × ΔA) × R (Expression (1)).

  On the other hand, the current density j can be defined as j = I / A (I: current value, A: effective electrode area). Assuming that jn = In / An in the nth generation and jn + 1 = (In + ΔI) / (An + ΔA) in the n + 1th generation, in this embodiment, ΔI is controlled so that jn = jn + 1, so In / An = ( In + ΔI) / (An + ΔA), and ΔI = In / An × ΔA (Expression (2)).

  From the equations (1) and (2), ΔI = jn × (ΔU / (k × R)) is derived, and furthermore j0 = j1 =... = Jn, ΔI = j0 × (ΔU / (k × R)) (Equation (3)). Here, k × R is a parameter that depends on the experimental system, such as electrode arrangement and concentration, and is a constant value. Therefore, ΔU is detected, ΔI is calculated from Equation (3) based on this ΔU, the current value flowing between the cathode 12 and the anode 11 is controlled, and the waveform of potential oscillation in the next generation is controlled. .

  FIG. 23 is a graph showing an example of control of the current value by the control unit, where the horizontal axis indicates the passage of time, and the vertical axis indicates the current value passed between the working electrode (that is, the cathode 12) and the anode 11. As is apparent from the figure, the current value flowing between the working electrode (ie, the cathode 12) and the anode 11 increases with time. This is because the current value was gradually increased so as to offset the effect of the increase in consideration of the increase in effective electrode area over time, and the effective current density did not change. Spontaneous vibration can be continued. Accordingly, the potential oscillation does not stop even when approximately 250 seconds have elapsed. In this example, it was confirmed that the potential oscillation continued even after approximately 2000 seconds (approximately 600 times in terms of the number of vibrations) had elapsed.

  In addition, even if the potential oscillation is repeated, the current density does not change, so that the lattice spacing of the fine structure grown on the surface of the working electrode can maintain the pitch at the start of the oscillation, and the uniformity can be maintained. Excellent fine lattice structure. In this way, by considering the effective increase in electrode area over time and gradually increasing the current value so as to offset the effect of the increase, a fine lattice structure with a uniform lattice spacing can be obtained inexpensively. It becomes possible to manufacture in large quantities. In addition, although one lattice is on the scale of several tens to several hundreds of micrometers, if the electrochemical deposition method according to the present embodiment is used, as shown in FIG. You can get a body.

  Thereby, a bulk material having a microscopic microstructure can be obtained, and can be used as a new electrode bulk material. Although the use of the Sn fine lattice structure itself is limited, a fine structure (for example, a fine lattice structure) is used as a three-dimensional basic skeleton (template), and a conductor such as platinum is plated on the surface of the fine structure. Thus, an electrode having a high strength and an extremely wide surface area can be obtained. It also has the advantage that a crystallographically stable surface is exposed. Of course, what is necessary is just to select the material coat | covered to a fine structure according to a use, and copper oxide can be considered except platinum.

  On the contrary, a fine structure in which the fine structure is a blank pattern can be manufactured using the fine structure (for example, a fine lattice structure) as a three-dimensional template. For example, after the manufactured microstructure is polymerized in a polymer solution, Sn is removed (etched) with an etching solution such as hydrochloric acid, and the shape of the microstructure is hollow (like an ant's nest). A high molecular weight polymer can be produced. Since such a high molecular polymer has a porous structure, it can be expected as a use as a filter. In addition, since the lattice spacing can be adjusted by controlling the waveform of the electrochemical vibration, it is possible to form a plurality of structures with different spacings in the polymer.

  In the present embodiment, the upper end potential or the lower end potential for each oscillation of the electrochemical vibration is detected, and the control unit 10 controls the current flowing between the cathode 12 and the anode 11 based on the upper end potential or the lower end potential. However, the period of each vibration of the electrochemical vibration is calculated from the upper end potential or the lower end potential, and the current of the working electrode with respect to the solution is controlled based on the calculated period so as to obtain a current density at which spontaneous vibration occurs. You may do it.

  As described above, the electrochemical deposition method according to the present invention has been described with reference to specific embodiments, but the present invention is not limited thereto. A person skilled in the art can add various changes or improvements to the configurations and functions of the invention according to the above-described embodiments without departing from the gist of the present invention.

Claims (17)

In an electrochemical deposition method in which a voltage is applied or a current is applied between a plurality of electrodes immersed in a solution in which a substance capable of electrochemical deposition is dissolved in an ionic state, and the substance is deposited on the surface of the working electrode.
Controlling the potential or current of the working electrode with respect to the solution to cause electrochemical oscillation;
An electrochemical deposition method, wherein the structure of the substance is determined based on the waveform of the electrochemical vibration. Reaction inhibitory species are mixed in the solution,
A state in which the reaction-inhibiting species is attached to the surface of the working electrode and a state of not being attached spontaneously and alternately
The electrochemical deposition method according to claim 1, wherein the potential or current of the working electrode at which the electrochemical vibration occurs is controlled. The electrochemical deposition method according to claim 2, wherein the potential or current of the working electrode in which the electrochemical oscillation occurs is controlled by adjusting the concentration of the reaction-inhibiting species. The reaction-inhibiting species is a cationic surfactant having 10 or more carbon chains,
4. The electrochemical deposition method according to claim 2, wherein the potential or current of the working electrode in which the electrochemical vibration is generated is controlled by adjusting a carbon chain. 5. The electrochemical deposition method according to claim 1, wherein a waveform of the electrochemical vibration is controlled by adjusting a concentration of the substance. In the solution, a plurality of substances are dissolved in an ionic state,
The electrochemical deposition method according to claim 1, wherein the composition ratio of the structure composed of the plurality of substances is determined by controlling a waveform of the electrochemical vibration. The electrochemical deposition method according to claim 1, wherein the structure of the substance determined based on the waveform of the electrochemical vibration is a multilayer structure. The electrochemical deposition method according to claim 7, wherein a waveform of each layer of the multilayer structure and / or a composition ratio of each layer is determined by controlling a waveform of the electrochemical vibration. The electrochemical deposition method according to claim 1, wherein the substance is a metal. 2. The electrochemical deposition method according to claim 1, wherein the electrochemical oscillation is generated by controlling the potential or current of the working electrode such that the electrochemical deposition advances to diffusion control. 3. Detecting the upper end potential or the lower end potential for each vibration of the electrochemical vibration,
The electrochemical deposition method according to claim 10, wherein the current of the working electrode is controlled based on the detected fluctuation of the upper end potential or the lower end potential. The electrochemical deposition method according to claim 11, wherein the effective current density of the working electrode with respect to the solution is controlled to be substantially constant. The electrochemical deposition method according to claim 10, wherein a waveform of the electrochemical vibration is controlled by adjusting a concentration of the substance. Electrochemical deposition for causing a current to flow between a plurality of electrodes immersed in a solution in which a substance capable of electrochemical deposition is dissolved in an ionic state, causing electrochemical vibration and depositing the substance on the surface of the working electrode A device,
Detecting means for detecting an upper end potential or a lower end potential for each vibration of the electrochemical vibration;
An electrochemical deposition apparatus comprising: control means for controlling the current of the working electrode with respect to the solution based on the upper end potential or the lower end potential detected by the detection means. The electrochemical deposition apparatus according to claim 14, wherein the control means controls the current density to generate spontaneous vibration.   A fine structure characterized in that a substance deposited by the electrochemical deposition method according to any one of claims 1 to 13 is used as a three-dimensional basic skeleton, and another substance is deposited on the surface of the substance. body.   A porous structure is formed inside by polymerizing another substance on the surface of the substance deposited by the electrochemical deposition method according to any one of claims 1 to 13, and removing the deposited substance. A fine structure characterized by that.

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