JP6806014B2 - Metal film film forming equipment - Google Patents

Description

The present invention relates to a film forming apparatus for forming a metal film on the surface of a base material, and in particular, by applying a voltage between an anode and the base material, a metal film having a different film thickness is formed on the surface of the base material. The present invention relates to a metal film forming apparatus capable of forming a film.

Conventionally, when forming a metal film on the surface of a base material, a film forming apparatus provided with a solid electrolyte film has been used. As such a film forming apparatus, for example, Patent Document 1 proposes a film forming apparatus for partially forming a metal film on the surface of a base material. This film forming apparatus includes an anode, a solid electrolyte membrane arranged between the anode and the substrate, a solution accommodating portion for accommodating a metal solution so as to come into contact with the anode and the solid electrolyte membrane, and the anode and the substrate. It is equipped with a power supply unit that applies a voltage between the two.

On the solid electrolyte film of this film forming apparatus, the solid electrolyte film comes into contact with the film forming region on the surface of the base material on which the metal film is formed, and the solid electrolyte film is not in contact with the surface other than the film forming region. As described above, a recess is formed with respect to the contact surface in contact with the film-forming region. As a result, the contact surface of the solid electrolyte film partially contacts the film formation region, so that a metal film can be partially formed on the surface of the base material.

Japanese Unexamined Patent Publication No. 2016-169398

However, when the film forming apparatus shown in Patent Document 1 is used, metal is uniformly deposited at the interface where the solid electrolyte film and the base material are in contact with each other, so that metal films having different thicknesses are formed on the base material. Then, after forming the thin metal film, it is necessary to re-simulate using the solid electrolyte membrane in which the recess is formed in the region other than the region where the thick metal film is desired to be formed, which takes time for production.

The present invention has been made in view of these points, and an object of the present invention is to provide a metal film forming apparatus capable of easily forming metal films having different thicknesses.

In view of these points, the metal film forming apparatus according to the present invention includes an anode, a solid electrolyte film arranged between the anode and a base material serving as a cathode, and the anode and the solid electrolyte film. A power source that applies a voltage between the solution accommodating portion accommodating the metal solution and the anode and the base material so that the metal solution containing metal ions comes into contact with the anode and the solid electrolyte membrane. A metal film film forming apparatus provided with a portion, wherein the solution accommodating portion pressurizes the accommodating metal solution onto the solid electrolyte membrane, and the inside of the solution accommodating portion includes. A shielding plate adjacent to the solid electrolyte membrane and having a plurality of through holes formed is arranged so as to cover the solid electrolyte membrane, and the shielding plate has a relative dielectric constant of 2.0 to 5.4. It is a dielectric of the above, and is characterized by being made of a resin material having a tensile strength of 19 to 80 MPa and a bending elasticity of 50 GPa or less.

According to the present invention, metal ions are deposited in the region where the solid electrolyte membrane and the base material are in contact with each other. In addition, since the relative permittivity of the shielding plate is set to a dielectric of 2.0 to 5.4, when the positive charge increases near the anode and the negative charge increases near the base material, the interface between the base material and the solid electrolyte film Dielectric polarization (interfacial polarization) occurs in. As a result, a thicker metal film is formed on the base material in the portion corresponding to the through hole of the shielding plate. In this way, metal films having different thicknesses can be formed on the base material in one film forming step.

Further, since the solution accommodating portion pressurizes the accommodating metal solution (electrolyte solution) on the solid electrolyte membrane, the solid electrolyte membrane is deformed by the hydraulic pressure of the metal solution. Even in such a case, a resin material having a tensile strength of 19 to 80 MPa and a flexural modulus of 50 GPa or less was selected as the material of the shielding plate, so that the shielding plate was used for stress deformation of the solid electrolyte membrane. It can be made to follow. Therefore, the thickness of the metal film can be increased according to the shape of the through hole of the shielding plate, and the metal film can be formed so that the shape corresponding to the shape of the through hole becomes clear.

Further, if a slight gap is provided between the solid electrolyte membrane and the shielding plate in the solution accommodating portion, the gas generated at the interface between the solid electrolyte membrane and the shielding plate will not be accumulated, so that the solid with respect to the base material. It is possible to suppress variations in the surface pressure of the electrolyte membrane.

It is a schematic disassembled perspective view of the metal film film forming apparatus of the embodiment of this invention. (A) is a cross-sectional view of a main part of the film forming apparatus shown in FIG. 1, and (b) is a cross-sectional view showing a state before film formation of (a). It is a schematic diagram for demonstrating the film formation of a metal film by the film forming apparatus shown in FIG. (A) and (b) are graphs showing the voltage change between the anode and the base material according to Examples 1 and 2. (A) and (b) are graphs showing the voltage change between the anode and the base material according to Examples 3 and 4. (A) and (b) are graphs showing the voltage change between the anode and the base material according to Comparative Examples 1 and 2. It is a graph which showed the voltage change between the anode and the base material which concerns on Comparative Example 3. (A) and (b) are graphs showing voltage changes between the anode and the base material according to Comparative Examples 4 and 5. 3 is a graph showing the relationship between the relative permittivity of the shielding plate and the weight of the nickel film in Examples 1 to 4 and Comparative Examples 2 and 3. 3 is a graph showing the relationship between the tensile strength of the shielding plate and the weight of the nickel film in Examples 1 to 4 and Comparative Examples 2 and 3. 3 is a graph showing the relationship between the flexural modulus of the shielding plate and the weight of the nickel film in Examples 1 to 4 and Comparative Examples 2 and 3.

Hereinafter, a film forming apparatus capable of preferably performing film formation of a metal film according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

1-1. About the film forming apparatus 1 FIG. 1 is a schematic exploded perspective view of the film forming apparatus 1 of the metal film according to the embodiment of the present invention, and FIG. It is a figure, (b) is the cross-sectional view which shows the state before film formation of (a). FIG. 3 is a schematic diagram for explaining the film formation of the metal film F by the film forming apparatus 1 shown in FIG. As shown in FIG. 1, the film forming apparatus 1 according to the present embodiment is an apparatus for forming a metal film F on the surface wf of the base material W.

When the surface wf of the base material W is a metal, the base material W may be made of an aluminum-based (aluminum or an alloy thereof) material or a copper-based (copper or an alloy thereof) material, and is a silicon substrate or a resin. It may be a base material in which the above-mentioned metal surface layer is formed on the surface of a non-conductive substrate such as a substrate.

The film forming apparatus 1 contains a metal containing metal ions so as to contact the anode 11, the solid electrolyte film 13 arranged between the anode 11 and the base material W serving as the cathode, and the anode 11 and the solid electrolyte film 13. A solution accommodating unit 15 accommodating the solution L and a power supply unit 16 for applying a voltage between the anode 11 and the base material W are provided.

Examples of the anode 11 include ruthenium oxide, platinum, and iridium oxide that are insoluble in the metal solution L, and the anode may be an anode in which these metals are coated on a copper plate or the like. In the present embodiment, the anode 11 may be a soluble anode made of the same metal as the metal of the metal film (metal of the metal ion of the metal solution L). For example, when the metal film is a nickel film, the anode 11 may be a soluble anode. The anode 11 is made of nickel.

The solid electrolyte membrane 13 can be impregnated with metal ions by bringing it into contact with the above-mentioned metal solution L, and when a voltage is applied, the metal derived from the metal ions can be deposited on the surface of the base material W. If possible, it is not particularly limited. Examples of the material of the solid electrolyte membrane include fluororesins such as Nafion (registered trademark) manufactured by DuPont, hydrocarbon resins, polyamic acid resins, and ion exchanges such as Celemion (CMV, CMD, CMF series) manufactured by Asahi Glass Co., Ltd. A resin having a function can be mentioned.

The solution accommodating portion 15 accommodates the metal solution L between the anode 11 and the solid electrolyte membrane 13 so that the metal solution L comes into contact with the anode 11 and the solid electrolyte membrane 13. The solution accommodating portion 15 is formed with a supply passage 15a for supplying the metal solution L and a discharge passage 15b for discharging the supply passage 15a. The solution accommodating portion 15 is made of a material that is insoluble in the metal solution L, and may be made of either metal or resin.

Examples of the metal solution L include an electrolytic solution containing ions such as copper, nickel, and silver. In the metal solution L, a metal to be a metal film exists in an ion state.

The solution accommodating unit 15 is connected to the solution supply device 21. The solution supply device 21 includes a storage tank (not shown) for accommodating the metal solution L and a pressure pump (not shown) for pumping the metal solution L from the storage tank, and supplies the solution storage unit 15. The metal solution L is connected to the passage 15a so as to be pumped and supplied. As a result, the solution accommodating unit 15 can pressurize the accommodating metal solution L on the solid electrolyte membrane 13.

Further, the solution supply device 21 is connected to the discharge passage 15b so as to recover the metal solution L from the discharge passage 15b of the solution storage unit 15. In this way, the solution supply device 21 can circulate the metal solution L in the device.

In the present embodiment, a plurality of (specifically, 4 × 4) through holes 14c are formed inside the solution accommodating portion 15 adjacent to the solid electrolyte membrane 13 so as to cover the solid electrolyte membrane 13. The shield plate 14 is arranged. The shielding plate 14 is preferably non-contact with the solid electrolyte membrane 13. The shielding plate 14 is made of a resin material having a relative permittivity of 2.0 to 5.4, a tensile strength of 19 to 80 MPa, and a flexural modulus of less than 50 GPa. Examples of the resin material of the shielding plate 14 include nylon 66, MC nylon (highly crystalline nylon), and vinyl chloride.

1-2. About the film forming method using the film forming apparatus 1 First, as shown in FIGS. 1 and 2B, the base material W is arranged at a position facing the solid electrolyte film 13 of the film forming apparatus 1. Next, the solid electrolyte membrane 13 is arranged on the base material W so that the surface of the solid electrolyte membrane 13 is in contact with the surface wf of the base material W.

In this arrangement state, the solution supply device 21 is operated to supply the metal solution L to the solution storage unit 15 and pressurize the metal solution L in the solution storage unit 15 to obtain a solid at the hydraulic pressure of the metal solution L. The electrolyte film 13 is pressed against the surface wf of the base material W.

Next, a voltage is applied between the anode 11 and the base material W by the power supply unit 16. As a result, as shown in FIG. 3, metal ions are precipitated in the region where the solid electrolyte film 13 and the base material W are in contact with each other, and the metal film F is formed on the surface of the base material W. Here, the diffusion layer shown in FIG. 3 is a layer in which a metal solution containing metal ions is diffused from the solid electrolyte film 13 to the base material W, and even in this layer, a small amount of metal is deposited.

In the present embodiment, since the relative permittivity of the shielding plate 14 is set to a dielectric of 2.0 to 5.4, when the positive charge increases near the anode 11 and the negative charge increases near the base material W, the base Dielectric polarization (interfacial polarization) occurs at the interface between the material W and the solid electrolyte film 13. As a result, a thicker metal film F is formed on the surface wf of the base material W in the portion of the shielding plate 14 corresponding to the through hole 14c. In this way, metal films F having different thicknesses can be formed on the surface wf of the base material W in one film forming step.

Further, since the solution accommodating portion 15 pressurizes the accommodating metal solution (electrolyte solution) L on the solid electrolyte membrane 13, the solid electrolyte membrane 13 is deformed by the hydraulic pressure of the metal solution L. Even in such a case, a resin material having a tensile strength of 19 to 80 MPa and a flexural modulus of less than 50 GPa was selected as the material of the shielding plate 14, so that the stress deformation of the solid electrolyte film 13 can be caused. The shielding plate 14 can be made to follow. Therefore, the thickness of the metal film F can be increased according to the shape of the through hole 14c of the shielding plate 14, and the metal film F can be formed so that the shape corresponding to the shape of the through hole 14c becomes clear. ..

If a slight gap is provided between the solid electrolyte membrane 13 and the shielding plate 14 in the solution accommodating portion 15, the gas generated at the interface between the solid electrolyte membrane 13 and the shielding plate 14 will not be accumulated. It is possible to suppress the variation in the surface pressure of the solid electrolyte membrane 13 with respect to W.

Here, the polarization of the solid electrolyte membrane 13 and the shielding plate 14 when a voltage is applied between the anode 11 and the base material W by the power supply unit 16 will be described. Since the solid electrolyte membrane 13 and the shielding plate 14 are made of a polymer resin and are insulators, they do not conduct electricity. However, when the polymer resin is placed in an electric field by applying a voltage by the power supply unit 16, electrons, atoms, and dipoles are excited and these are polarized. These polarizations occur inside the solid electrolyte membrane 13 and the shielding plate 14.

Electron polarization is polarization in which electrons localized between atoms are excited and divided into a segment toward a positive electrode and a segment toward a negative electrode, causing an electron bias in the entire molecule. Atomic polarization is the polarization that occurs when atoms distributed with positive and negative charges are attracted to and deviated from their respective electrodes. Dipole polarization (orientation polarization) is a phenomenon in which when a molecule having a polar functional group is placed in an electric field, the polarized dipoles rotate and orient, resulting in further polarization.

Further, the interfacial polarization is a phenomenon in which electric charges are accumulated at the interface and polarized when the ratio of the dielectric constant and the conductivity between the phases is different in the inhomogeneous dielectric material, which is called the Maxwell-Wagner effect. In the present embodiment, this interfacial polarization occurs at the interface between the base material W and the solid electrolyte membrane 13.

Specifically, when a current flows into the interface of the above-mentioned materials having different relaxation times for relaxing the polarization, electric charge is accumulated at the interface. More specifically, the rate of charge spread in the material is controlled by the relaxation time, but at the interface of different materials, the rate of charge spread is different, resulting in charge accumulation. The accumulation of electric charges at the interfaces of different materials in this way causes interfacial polarization.

When the metal film F is formed by using the shielding plate 14 made of a dielectric (insulator), the Maxwell-Wagner effect is also taken into consideration, and the dielectric polarization (when the metal ion approaches the conductor, the inside of the conductor is formed. A phenomenon in which free electrons move, negative electricity having a different sign is generated on the side closer to the metal ion, and positive electricity having the same sign appears on the far side) occurs.

In the following examples, shielding plates having different dielectric constants are arranged at the interface between the solid electrolyte film which is a dielectric and the metal solution, and a voltage is applied between the electrodes to cause the interfacial polarization (Maxwell-Wagner effect) to be a metal film. The effect on the metal film was investigated qualitatively from the morphological observation of the metal film and quantitatively from the weight measurement of the metal film.

The present invention will be described below based on examples.

<Example 1>
Nickel plate as an anode (product number: NI-313551, size: thickness 2 mm x 40 x 50 mm, manufactured by Niraco Co., Ltd.), and as an electrolytic solution (metal solution) (1 M nickel chloride, acetic acid / nickel acetate buffer solution 0. A 5M) aqueous solution (pH 3.0) and an ion exchange film (electrolyte film: CSH50, manufactured by Asahi Glass Co., Ltd.) were prepared as a solid electrolyte film.

A resin shielding plate made of nickel foil (thickness: 15 μm, size; 260 × 35 mm, manufactured by Fukuda Metal Foil Powder Industry Co., Ltd.) as a base material as a cathode and nylon 66 as a shielding plate (size). : 30 × 30 × 2 mm, through hole diameter; 2 mm, through random number; 16, pitch: 4 mm) was prepared.

The film forming conditions were a substrate temperature of 80 ° C., a pressure (hydraulic pressure) of 0.5 MPa, a film forming rate of 20 μm / min, a nickel film film forming area of 50 mm ² , and a nickel film film of 50 μm. Before forming a nickel film on the nickel foil (base material), the nickel foil was rinsed with 25% hydrochloric acid for 10 minutes, and a shielding plate was placed at the interface between the metal solution and the solid electrolyte film. Nylon 66, which is a shielding plate, is a resin material having a relative permittivity of 3.45, a tensile strength of 80 MPa, and a flexural modulus of 2.9 GPa.

The relative permittivity of the shielding plate was adjusted to JlS C2101 using a capacitance type relative permittivity measuring device (product name; DPS17, DC bias; 40V, AC amplitude voltage; 5mV-2Vrms, Keycom Co., Ltd.). Measured based on. The mechanical properties (tensile strength and flexural modulus) of the shielding plate were measured based on JISK7161 and JISK7171 using a universal tensile tester (product number: 5566, Instron).

The total weight of the solid electrolyte film and the base material was measured before and after the formation of the nickel film, and the difference in the total weight was defined as the weight of the nickel film formation. In addition, the appearance of the nickel film was observed with a microscope (Keyence Co., Ltd., VH-8000). Here, the reason why the total weight of the electrolyte film and the nickel base material was measured when measuring the weight of the nickel film is that the nickel film grows on the surface of the solid electrolyte film due to the Maxwell-Wagner effect when the nickel film is formed. However, there is a high possibility that the nickel film and the electrolyte film are in close contact with each other, making it difficult to measure the weight of the nickel film.

<Example 2>
A nickel film was formed in the same manner as in Example 1. The difference from the first embodiment is that the shielding plate is made of MC nylon (highly crystalline nylon). The shielding plate MC nylon (highly crystalline nylon) is a resin material having a relative permittivity of 4.25, a tensile strength of 76 MPa, and a flexural modulus of 2.5 GPa.

<Example 3>
A nickel film was formed in the same manner as in Example 1. The difference from the first embodiment is that the shielding plate is made of vinyl chloride. The vinyl chloride of the shielding plate is a resin material having a relative permittivity of 5.4, a tensile strength of 19 MPa, and a flexural modulus of 2.9 GPa.

<Example 4>
A nickel film was formed in the same manner as in Example 1. The difference from Example 1 is that the shielding plate is made of polytetrafluoroethylene (PTFE) or the like. The shielding plate polytetrafluoroethylene is a resin material having a relative permittivity of 4, a tensile strength of 25 MPa, and a flexural modulus of 0.5 GPa.

<Comparative example 1>
A nickel film was formed in the same manner as in Example 1. The difference from the first embodiment is that the shielding plate is not provided.

<Comparative example 2>
A nickel film was formed in the same manner as in Example 1. The difference from the first embodiment is that the shielding plate is made of stainless steel (SUS304). The stainless steel of the shielding plate is a metal material having a relative permittivity of 1, a tensile strength of 520 MPa, and a flexural modulus of 197 GPa.

<Comparative example 3>
A nickel film was formed in the same manner as in Example 1. The difference from Example 1 is that the shielding plate is made of phenol resin. The phenolic resin of the shielding plate is a dielectric material having a relative permittivity of 7.5, a tensile strength of 5 MPa, and a flexural modulus of 8 GPa. Therefore, in Comparative Example 3, the relative permittivity and tensile strength of the phenolic resin are out of the scope of the present invention.

<Comparative example 4>
A nickel film was formed in the same manner as in Example 1. The difference from the first embodiment is that the shielding plate is made of a silicone resin. The silicone resin of the shielding plate is a dielectric material having a relative permittivity of 5, a tensile strength of 120 MPa, and a flexural modulus of 13 GPa. Therefore, in Comparative Example 4, the tensile strength of the silicone resin exceeds the scope of the present invention.

<Comparative example 5>
A nickel film was formed in the same manner as in Example 1. The difference from the first embodiment is that the shielding plate is made of urethane rubber. The urethane rubber of the shielding plate is a resin material having a relative permittivity of 7, a tensile strength of 60 MPa, and a flexural modulus of 10 GPa. Therefore, in Comparative Example 5, the relative permittivity of the urethane rubber exceeds the range of the present invention.

(Measurement of voltage change during film formation and its result)
The voltage change between the anode and the substrate was measured when the film was formed by the film forming apparatus of Examples 1 to 4 and Comparative Examples 1 to 5. The results are shown in FIGS. 4 to 8. 4 (a) and 4 (b) are graphs showing voltage changes between the anode and the base material according to Examples 1 and 2, and FIGS. 5 (a) and 5 (b) are FIGS. It is a graph which showed the voltage change between the anode and the base material which concerns on 4. 6 (a) and 6 (b) are graphs showing voltage changes between the anode and the base material according to Comparative Examples 1 and 2. FIG. 7 is a graph showing the voltage change between the anode and the base material according to Comparative Example 3. 8 (a) and 8 (b) are graphs showing voltage changes between the anode and the base material according to Comparative Examples 4 and 5. The nickel film formed was observed with the above-mentioned microscope.

When there is no shielding plate of Comparative Example 1, as shown in FIG. 6A, the voltage becomes a constant square wave, nickel hydroxide is formed on the solid electrolyte film side, and a nickel film is formed on the cathode (base material) side. It was formed, but the film was not uniform.

When the material of the shielding plate of Comparative Example 2 is a conductor (stainless steel), as shown in FIG. 6 (b), the potential increases with time from the application of voltage, and after reaching the maximum value, a two-step plateau It was cut off through the area. It was found that a nickel film was not formed on the through-hole shape of the shielding plate. It is considered that this is because in the case of Comparative Example 2, since the shielding plate made of the conductor (metal) was used, electrostatic induction and electric charge-up occurred.

On the other hand, as the material of the shielding plate is a dielectric (insulator), nylon 66 (Example 1), MC nylon (Example 2), vinyl chloride (Example 3), polytetrafluoroethylene (Example 4), and When a phenol resin (Comparative Example 3) is used, when the formed nickel film is observed, a thick nickel film is formed according to the shape of the through hole of the shielding plate. It is considered that the nickel ions converged on the through holes.

However, even if the material of the shielding plate is a dielectric (insulator), when silicone resin (Comparative Example 4) and urethane rubber (Comparative Example 5) are used as the material of the shielding plate, the through holes of the shielding plate are used. It is considered that a thick nickel film was not formed according to the shape of the film, and the nickel ions did not converge on the through holes during the film formation.

Further, from FIGS. 4, 5, and 7, nylon 66 (Example 1), MC nylon (Example 2), among the dielectrics (insulators) capable of converging nickel ions in the shape of the through hole of the shielding plate, In polytetrafluoroethylene (Example 4) and phenol resin (Comparative Example 3), the voltage increases with time from the application of the voltage, reaches a maximum value, then gradually decreases, and is cut off via the plateau region. Was there. On the other hand, in vinyl chloride (Example 3), the voltage increases with time, reaches a maximum value and then rapidly increases, reaches a plateau region (between 80 seconds and 140 seconds) after reaching 10 V, and becomes 140. It was found that it was cut off by taking two maximums from seconds and decreasing.

As described above, it was found that when a shielding plate made of a dielectric (insulator) is used, nickel ions can be converged to the shape of the through hole of the shielding plate under certain conditions. On the other hand, it was found that nickel ions could not be converged when a shielding plate made of metal (conductor) was used.

Note that FIG. 7 illustrates the phenomenon of each time in the time-voltage curve using the shielding plate made of phenol resin. To form the nickel film described above, a small voltage is applied to the anode and the base material (cathode) by a constant current method, and then the voltage is increased to the value required for forming the nickel film to form the nickel film. Carried out. The phenomenon that occurs at that time proceeds as shown in FIG. 7 (1) → (2) → (3) → (4).

As shown in the voltage waveform (1) shown in FIG. 7, when a small voltage is applied between the anode and the substrate (cathode), teleportation of ions contained in the metal solution occurs, and charges are accumulated at each interface in a short time. To do.

Next, as shown in the voltage waveform (2), when the voltage is further increased, the electric energy at the interface where the phases having different electrical properties are in contact becomes a sufficient value, and the electric double layer and the interface polarization are formed (electricity). Non-faraday current to charge the double layer flows).

Next, as shown in the voltage waveform (3), the metal solution donates electrons to the anode, receives electrons from the base material (cathode), and the electrolytic reaction starts. As the electrolytic reaction progresses, the positive charge of the metal solution near the anode increases (the negative charge decreases), and the negative charge of the solution near the substrate (cathode) increases (the positive charge decreases) (electron transfer rate control). Faraday current flows).

Next, as shown in the voltage waveform (4), in order to cancel the excess charge and form electrical neutrality, the anion in the solid electrolyte membrane and the metal solution is the anode, and the cation in the metal solution is the substrate (cathode). ), Nickel ions are dissolved from the anode, nickel ions are transported to the base material (cathode), and a nickel film is formed on the surface of the base material (cathode) (diffusion-determining faraday current flows). At this time, since interfacial polarization occurs, nickel can be converged on the base material (cathode). Therefore, in order to converge the uniform nickel ions, it is conceivable to select (4) a shielding plate made of a material that makes the voltage in the formation of the nickel film a plateau.

Here, in the hydraulic method in which the solid electrolyte film is pressed against the base material by the hydraulic pressure of the metal solution, the solid electrolyte film is formed with the metal solution arranged between the anode and the solid electrolyte film at the time of film formation. Contact the substrate. In this state, when a voltage is applied between the anode and the base material (cathode), the nickel ions contained in the metal solution move from the anode side to the cathode side (base material side) and are contained inside the solid electrolyte membrane. Further, the nickel ions can be precipitated on the cathode side of the solid electrolyte membrane. Even during this film formation, according to Pascal's principle, the solid electrolyte film uniformly pressurizes the surface of the base material by the hydraulic pressure of the pressurized solution, so that a nickel film having a uniform thickness is formed on the surface of the base material. Can be filmed.

Further, a shielding plate having through holes formed at the interface between the solid electrolyte membrane and the metal solution was placed. In the hydraulic method, when the solid electrolyte membrane is brought into contact with the base material (cathode), the metal solution is pressurized, so that the hydraulic pressure of the metal solution pressurizes the base material (cathode) through the solid electrolyte membrane. , A nickel film was formed. Therefore, the solid electrolyte film and the shielding plate during the film formation are deformed by the pressure and are dielectrically polarized by the electrostatic field. Therefore, the physical properties (mechanical and electrical) of the shielding plate, which depend on the weight of the nickel film, were investigated.

FIG. 9 is a graph showing the relationship between the relative permittivity of the shielding plate and the weight of the nickel film in Examples 1 to 4 and Comparative Examples 2 and 3. FIG. 10 is a graph showing the relationship between the tensile strength of the shielding plate and the weight of the nickel film in Examples 1 to 4 and Comparative Examples 2 and 3. Further, FIG. 11 is a graph showing the relationship between the flexural modulus of the shielding plate and the weight of the nickel film in Examples 1 to 4 and Comparative Examples 2 and 3.

From FIG. 9, it was found that the nickel film weight became the maximum value in the range of the relative permittivity of 2.0 to 5.4. From FIG. 10, it was found that the nickel film weight had a maximum value in the range of the tensile strength of 19 to 80 MPa. From FIG. 11, it was found that the nickel film weight increased in the range where the flexural modulus was 50 GPa or less.

It can be presumed that the reason why the optimum range exists in the relative permittivity of the shielding plate is that interfacial polarization (Maxwe11-Wagner effect) in which electric charges are accumulated at the interface where phases having different electrical properties are in contact with each other occurs during film formation. When the relative permittivity of the shielding plate is less than 2.0 and exceeds 5.4, such an effect cannot be obtained. As in Comparative Example 2, when a metal shielding plate was used, nickel ions could not be converged because electrostatic induction occurred on the shielding plate surface (dielectric polarization did not occur) and interfacial polarization (Maxwell-Wagner). Effect) does not occur.

Here, when the tensile strength of the shielding plate is less than 19 MPa, it is considered that when the base material (cathode) is pressurized with the solid electrolyte membrane, the through holes are deformed and the nickel ions are difficult to converge. On the other hand, when the tensile strength of the shielding plate exceeds 80 MPa, when the base material (cathode) is pressurized with the solid electrolyte film, the shielding plate cannot follow the deformation of the solid electrolyte film, and it becomes difficult for nickel ions to converge. It is thought that it is from.

Further, even when the flexural modulus of the shielding plate exceeds 50 GPa, when the solid electrolyte film is deformed during film formation, the shielding plate cannot follow the deformation of the solid electrolyte film, and it becomes difficult for nickel ions to converge. Is considered to be.

Although one embodiment of the present invention has been described in detail above, the present invention is not limited to the above-described embodiment, and various types are described within the scope of claims without departing from the spirit of the present invention. It is possible to make design changes.

1: Film formation device, 11: Anode, 13: Solid electrolyte film, 14: Shielding plate, 14c: Through hole, 15: Solution storage part, 16: Power supply part, L: Metal solution, W: Base material

Claims (1)

With the anode
A solid electrolyte membrane arranged between the anode and the base material serving as the cathode,
A solution accommodating portion for accommodating the metal solution so that the metal solution containing metal ions comes into contact with the anode and the solid electrolyte membrane between the anode and the solid electrolyte membrane.
A metal film forming apparatus provided with a power supply unit for applying a voltage between the anode and the base material.
The solution accommodating portion pressurizes the contained metal solution onto the solid electrolyte membrane.
Inside the solution accommodating portion, a shielding plate adjacent to the solid electrolyte membrane and having a plurality of through holes formed is arranged so as to cover the solid electrolyte membrane.
The shielding plate is a metal having a relative permittivity of 2.0 to 5.4, a tensile strength of 19 to 80 MPa, and a bending elastic modulus of 50 GPa or less. Film deposition equipment.

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