JP2017088918A - Metal film formation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal film formation device where the leakage of a metal solution from a solution chamber is suppressed, and, with a simple device constitution, a metal film is formed while uniformly contacting the surface of a base material with a solid electrolytic membrane.SOLUTION: Provided is a film formation device 1 at least comprising: an anode 11; a solid electrolytic membrane 13 arranged between the anode 11 and a base material B; a solution chamber 15 arranged between the anode 11 and the solid electrolytic membrane 13 and storing a metal solution; and a power source part 16 of applying voltage to a space between the anode 11 and the base material B. The solution chamber 15 is formed of: a housing 12 including an opening part 12a having a storage space S storing a metal solution L and having an opening part 12a in which the storage space S is released to the base material side; and an elastic body 14 fitted to the opening part 12a of the housing 12, the solid electrolytic membrane 13 is fitted to the solution chamber 15 via the elastic body 14. The elastic body 14 stretches to the outside of the solution chamber 15 along the pressing direction in such a manner that, when the solid electrolytic membrane 13 is pressed against the base material B, compressive deformation is possible to the pressing direction of the base material B.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a film forming apparatus for forming a metal film on the surface of a substrate, and in particular, a metal film capable of suitably forming a metal film by applying a voltage between an anode and a substrate. The present invention relates to a film forming apparatus.

  Conventionally, a technique for forming a metal film by depositing metal ions on the surface of a substrate has been proposed. As such a technique, for example, as shown in FIG. 6, the anode 11, the solid electrolyte membrane 13 disposed between the anode 11 and the substrate B (cathode), the anode 11 and the cathode (substrate B), A metal film deposition apparatus 8 having a power supply unit 16 for applying a voltage between them is proposed.

  In the film forming apparatus 8, a solution chamber 15 that is disposed between the solid electrolyte membrane 13 and the anode 11 and that stores the metal solution L is formed. The solution chamber 15 is formed by the housing 12 and the solid electrolyte membrane 13. The solid electrolyte membrane 13 is attached so as to seal the opening 12 a of the housing space S of the housing 12.

  Further, the solution chamber 15 is connected to a high-pressure pump 17 that increases the liquid pressure of the metal solution L in the solution chamber 15. The film forming apparatus 8 is provided with a pressure unit (cylinder) 18 for pressing the solid electrolyte membrane 13 toward the base material B.

  Here, when the metal film F is formed on the surface of the base material B, the liquid pressure of the metal solution L in the solution chamber 15 is set in a state where the solid electrolyte membrane 13 is pressed against the base material B by the pressurizing unit 18. The pressure is increased by the high pressure pump 17. In this state, a voltage is applied between the anode 11 and the base material B to reduce metal ions derived from the metal solution L contained in the solid electrolyte membrane 13, thereby forming the metal film F on the base material B. The film can be formed on the surface.

  According to the film forming apparatus 8 described above, the liquid pressure of the metal solution L in the solution chamber 15 is reduced in a state where the solid electrolyte film 13 is pressed against the base material B mounted on the mounting table 40 during film formation. Increase pressure. Thereby, the metal film F can be formed by making the solid electrolyte membrane 13 follow the surface of the base material B.

JP 2014-051701 A

  However, the film forming apparatus 8 according to Patent Document 1 includes a high pressure pump 17 and a pressurizing unit 18 as means for bringing the solid electrolyte membrane 13 into uniform contact with the surface of the base material B, and controls these. The device configuration is complicated.

  Therefore, for example, when the film forming apparatus 9 in which the pressurizing unit 18 is omitted is used, as shown in FIG. 7, the solid electrolyte membrane 13 is held at a certain distance with respect to the base material B. The housing 12 of the film forming apparatus 9 is fixed. When forming the metal film, the pressure of the metal solution L is increased by the high-pressure pump 17 to deform the solid electrolyte film 13 toward the base material B, and the solid electrolyte film 13 contacts the base material B. Let However, in the film forming apparatus 9, it is difficult to bring the solid electrolyte film 13 deformed by the liquid pressure of the metal solution L into uniform contact with the surface of the base material B.

  Therefore, in order to bring the solid electrolyte membrane 13 into contact with the surface of the base material B more uniformly, the liquid pressure of the metal solution L is further increased by the high-pressure pump 17 in the film forming apparatus 9 shown in FIG. Deformation is also envisaged. However, due to further pressure increase of the metal solution L and deformation of the solid electrolyte membrane 13, the sealing performance between the housing 12 and the solid electrolyte membrane 13 is impaired, and the metal solution L may leak from the solution chamber 15 to the outside. .

  The present invention has been made in view of the above points. The object of the present invention is to suppress the leakage of the metal solution from the solution chamber and to make the solid electrolyte membrane of the base material with a simpler device configuration. An object of the present invention is to provide a metal film deposition apparatus capable of depositing a metal film while uniformly contacting the surface.

  In order to solve the above problems, a metal film deposition apparatus according to the present invention includes an anode, a solid electrolyte membrane disposed between the anode and the base material serving as the cathode, the anode, and the solid electrolyte membrane. A solution chamber for accommodating the metal solution so that the metal solution is in contact with the anode and the solid electrolyte membrane, and a power supply unit for applying a voltage between the anode and the substrate. A metal derived from the metal solution contained in the solid electrolyte membrane by applying a voltage between the anode and the substrate in a state in which the solid electrolyte membrane is pressed against the substrate. A metal film-forming apparatus for forming a metal film on the surface of the substrate by reducing ions, wherein the solution chamber has a storage space for storing the metal solution, and the storage space is A housing having an opening opened to the substrate side; and The solid electrolyte membrane is attached to the solution chamber via the elastic body, and the elastic body attaches the solid electrolyte membrane to the substrate. It extends to the outside of the solution chamber along the pressing direction so that it can be compressed and deformed in the pressing direction of the base material when pressed onto the substrate.

  According to the present invention, when the solid electrolyte membrane is pressed against the substrate, the elastic body compresses and deforms in the pressing direction of the substrate, so that the volume of the metal solution in the solution chamber is reduced, and the pressure of the metal solution in the solution chamber is reduced. Is increased. Thereby, a solid electrolyte membrane can be uniformly pressed on the surface of a substrate.

  In this pressed state, when a voltage is applied between the anode and the substrate by the power supply unit, the metal ions supplied to the solid electrolyte membrane move to the surface of the substrate in contact with the solid electrolyte membrane, and the substrate The metal derived from metal ions is deposited on the surface of the substrate. Thereby, a metal film can be uniformly formed on the surface of the substrate. Since the metal solution is in contact with the solid electrolyte membrane while the metal solution is accommodated in the solution chamber, metal ions are supplied to the solid electrolyte membrane as needed.

  In addition, when the solid electrolyte membrane is pressed against the base material, the elastic body compresses and deforms in the pressing direction of the base material, so the elastic body provided between the housing and the solid electrolyte membrane acts as a sealant for the solution chamber. To do. Thereby, even if the pressure of the metal solution in the solution chamber is increased, it is possible to avoid leakage of the metal solution in the solution chamber from between the housing and the solid electrolyte membrane.

  Thus, according to the present invention, the metal film is formed while the solid electrolyte membrane is uniformly brought into contact with the surface of the substrate with a simpler apparatus configuration while suppressing the leakage of the metal solution from the solution chamber. can do.

1 is a schematic cross-sectional view of a metal film deposition apparatus according to an embodiment of the present invention. It is a typical sectional view for explaining the state at the time of film formation of the film formation apparatus shown in FIG. (A) is the enlarged view which showed the state which pressed the solid electrolyte membrane on the surface of the base material with the film-forming apparatus shown in FIG. 2, (b) is a state of the base material from the press state shown in (a). It is the enlarged view which showed the state in which the metal membrane | film | coat was formed into the surface. It is typical sectional drawing of the film-forming apparatus of the metal film which concerns on a comparative example. It is a figure for demonstrating the film-forming state of a metal film using the film-forming apparatus which concerns on an Example and a comparative example. It is typical sectional drawing of the film-forming apparatus of the metal film concerning the former. It is typical sectional drawing of the film-forming apparatus of the other metal film based on the past.

1. Film Forming Apparatus 1 FIG. 1 is a schematic cross-sectional view of a metal film forming apparatus 1 according to an embodiment of the present invention. As shown in FIG. 1, a film forming apparatus 1 according to the present invention is an apparatus that deposits a metal by reducing metal ions and forms a metal film made of the deposited metal on the surface of a base material B. .

  The substrate B is not particularly limited as long as the surface on which the film is formed functions as a cathode (that is, a surface having conductivity). Specifically, the base material B may be made of a metal material such as aluminum or iron, and a metal layer such as copper, nickel, silver, or iron is provided on the surface of a polymer resin such as an epoxy resin or ceramics. It may be coated. In this embodiment, the base material B is a base material in which a resist R is partially formed on the surface of a resin base material, and a metal thin film (not shown) is exposed on the surface exposed from the resist R. Is formed. Therefore, the metal thin film of the base material B has a surface on which the base material B is formed, and corresponds to the cathode in the present invention.

  The film forming apparatus 1 includes a metal anode 11, a solid electrolyte film 13 disposed between the anode 11 and the base material B (cathode), and a power source that applies a voltage between the anode 11 and the base material B. Part 16.

  The anode 11 is made of the same metal as the metal of the metal film, is a soluble anode that dissolves in the metal solution L, and is a block-like or flat-plate-like anode. The solid electrolyte membrane 13 can be impregnated (contained) with metal ions by being brought into contact with the metal solution L. When a voltage is applied, the metal ions are reduced on the surface of the base material B, and are derived from the metal ions. There is no particular limitation as long as the metal can be deposited.

  The metal solution L is a liquid (electrolytic solution) containing the metal of the metal film to be formed as described above in an ionic state. Such metals can include copper, nickel, silver, or iron, and the metal solution L can be dissolved in an acid such as nitric acid, phosphoric acid, succinic acid, nickel sulfate, or pyrophosphoric acid ( Ionized aqueous solution.

  Furthermore, the film forming apparatus 1 includes a solution chamber 15 that stores the metal solution L. The solution chamber 15 has the solid electrolyte membrane 13 and the anode so that the metal solution L contacts the anode 11 and the solid electrolyte membrane 13. 11.

  The solution chamber 15 is formed by the housing 12 and the elastic body 14. Specifically, the housing 12 has a storage space S for storing the metal solution L, and an opening 12a that opens the storage space S to the base material side. The solid electrolyte membrane 13 is attached to the housing 12 via a solution chamber 15 (specifically, an elastic body 14) so as to seal the opening 12a of the housing 12.

  The elastic body 14 is attached (adhered) between the housing 12 and the solid electrolyte membrane 13 so as to surround the periphery of the opening 12 a of the housing 12. Further, the elastic body 14 extends to the outside of the solution chamber 15 along the pressing direction so as to be compressible and deformable in the pressing direction of the base material B when the base material B is pressed against the solid electrolyte membrane 13. . The structure of the solution chamber 15 is not particularly limited as long as the inside of the solution chamber 15 can be kept sealed when the substrate B is pressed by the solid electrolyte membrane 13 during film formation.

  Examples of the material of the housing 12 include a metal material, and the material is not particularly limited as long as it can be made not to be excessively deformed (rigid body) by the pressurizing unit 18. In addition, the elastic body 14 can include the above-described compression-deformable rubber or resin, and is preferably a material that is not deteriorated by the metal solution L (for example, an acid-resistant material). Examples of the material of the elastic body 14 include silicone rubber.

  Furthermore, the film forming apparatus 1 is provided with a metal mounting table 40 on which the base material B is mounted. The negative electrode of the power supply unit 16 is connected to the mounting table 40, and the anode 11 has a power supply unit. Sixteen positive electrodes are connected. Here, the mounting table 40 and the surface (metal thin film (not shown)) on which the base material B is formed are electrically connected. Thereby, the surface of the base material B can be functioned as a cathode.

  In the present embodiment, the film forming apparatus 1 is further provided with a pressure unit 18 on the upper portion of the housing 12 via a buffer member 19 such as a spring. The pressurizing unit 18 may be a hydraulic or pneumatic cylinder, and is a device that presses the solid electrolyte membrane 13 against the base material B. Thereby, a metal film can be formed while pressing the solid electrolyte membrane 13 against the surface of the substrate B. Further, by providing the buffer member 19, the solid electrolyte membrane 13 can be gently pressed against the surface of the base material B.

2. About the film-forming method using the film-forming apparatus 1 The film-forming method using the film-forming apparatus 1 which concerns on this embodiment is demonstrated below. FIG. 2 is a schematic cross-sectional view for explaining a state during film formation of the film forming apparatus 1 shown in FIG. FIG. 3A is an enlarged view showing a state in which the solid electrolyte membrane 13 is pressed against the surface f of the base material B by the film forming apparatus 1 shown in FIG. FIG. 3B is an enlarged view showing a state in which the metal film F is formed on the surface f of the base material B from the pressed state shown in FIG.

  First, as shown in FIG. 1, a base material B on which a resist R and a metal thin film (not shown) are formed is placed on a mounting table 40 so as to face the solid electrolyte membrane 13. Next, as shown in FIG. 2, the housing 12 is lowered toward the mounting table 40 using the pressurizing unit 18, the solid electrolyte membrane 13 is brought into contact with the surface of the base material B, and the solid electrolyte membrane 13 is further removed. Press against the surface of the substrate B.

  Here, when the solid electrolyte membrane 13 is pressed against the base material, the elastic body compresses and deforms in the pressing direction of the base material B, so that the volume of the metal solution L in the solution chamber 15 decreases from V to V-dV. The pressure of the metal solution L in the solution chamber 15 is increased from P to P + dP.

  As a result, as shown in FIG. 3A, even when the surface of the base material B is an uneven surface on which the resist R is formed, the surface where the solid electrolyte membrane 13 is exposed from the resist R of the base material B ( It is possible to uniformly press the surface (f) of the metal thin film.

  In this pressed state, a voltage is applied between the anode 11 and the base material B by the power supply unit 16. The metal solution L in the solution chamber 15 is in contact with the anode 11 and the solid electrolyte membrane 13, and the metal ions supplied to the solid electrolyte membrane 13 are exposed on the exposed surface f of the substrate B in contact with the solid electrolyte membrane 13. Moving. The moved metal ions are reduced at the surface f exposed from the resist R of the substrate B, and the metal derived from the metal ions is deposited on the exposed surface f of the substrate B. Thereby, as shown in FIG. 3B, the metal film F can be uniformly formed on the exposed surface f of the base material B.

  Further, when the solid electrolyte membrane 13 is pressed against the base material B, the elastic body 14 is compressed and deformed in the pressing direction of the base material B, so that the elastic body 14 provided between the housing 12 and the solid electrolyte membrane 13 is provided. Acts as a sealant for the solution chamber. Thereby, even if the pressure of the metal solution L in the solution chamber 15 is increased, the leakage of the metal solution L in the solution chamber 15 from between the housing 12 and the solid electrolyte membrane 13 can be avoided. it can.

  Thus, according to the film forming apparatus 1 according to the present embodiment, the metal film F is formed with a simpler apparatus configuration without requiring a conventional high-pressure pump (for example, see FIGS. 6 and 7). can do.

  The invention is illustrated by the following examples.

[Example]
A metal film was formed using the film forming apparatus 1 shown in FIG. First, a glass epoxy substrate in which glass fibers were impregnated with an epoxy resin was prepared as a base material. A resist having a thickness of 35 μm is formed on the surface of the base material, and a copper land (copper thin film) having a diameter of 1.0 mm is formed on the surface exposed from the resist.

Next, 1.0 mol / L copper sulfate aqueous solution was prepared as a metal solution, and this was accommodated in the solution chamber. An oxygen-free copper plate was used for the anode, and an electrolyte membrane with a film thickness of 183 μm (DuPont: Nafion N117) was used for the solid electrolyte membrane. To conduct copper land of substrate (copper thin film) to the negative pole of the power source unit, while pressing at 0.5MPa the solid electrolyte film on the surface of the substrate, the anode and the substrate such that the current density 100 mA / cm ² During this period, a voltage was applied for 1 minute to form a copper film on the surface of the copper land of the substrate.

[Comparative example]
A copper film was formed on the same substrate as in the example. The difference from the example is that the film forming apparatus 7 shown in FIG. 4 was used and the film was formed under the conditions of a current density of 10 mA / cm ² for 10 minutes. The film forming apparatus used in the comparative example is different from that of the example in that the elastic body is not provided and the anode is made of a foamed titanium plate (made by Mitsubishi Materials) having a porosity of 85% and a pore diameter of 50 μm. The porous anode 91 is used, and this is brought into contact with the solid electrolyte membrane 13.

(Confirmation of film formation)
The shape of the copper film (2 places) formed in the examples and comparative examples was confirmed with a microscope, and the coverage of the copper film coated on the copper land was calculated. Specifically, the coverage of the copper film was calculated from the formula: coverage (%) = copper film area / copper land × 100. The result is shown in FIG.

<Results and discussion>
As shown in FIG. 5, in the case of the example, the coverage of the copper film was 100%, and the copper film was completely covered with the copper land. On the other hand, in the case of the comparative example, the coverage of the copper film was 20% and 14%, and the copper land was exposed from the copper film.

  From this, in the case of the example, the solid electrolyte membrane was pressed against the copper land of the base material by the liquid pressure of the metal solution, and unlike the case of the comparative example, the solid electrolyte membrane was uniformly pressed against the copper land. It is thought that the copper film could be formed on the copper land in the state.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs can be made without departing from the spirit of the present invention described in the claims. It can be changed.

DESCRIPTION OF SYMBOLS 1: Film-forming apparatus, 11: Anode, 12: Housing, 12a: Opening part, 13: Solid electrolyte membrane, 14: Elastic body, 15: Solution chamber, 16: Power supply part, 18: Pressurization part, 17: High pressure pump , 19: buffer member, 40: mounting table, B: base material, L: metal solution, F: metal film, R: resist, S: accommodation space

Claims (1)

An anode, a solid electrolyte membrane disposed between the anode and the substrate serving as the cathode, and a metal solution disposed between the anode and the solid electrolyte membrane, the metal solution being in contact with the anode and the solid electrolyte membrane And at least a power supply unit that applies a voltage between the anode and the base material, and the anode is pressed against the base material in a state where the solid electrolyte membrane is pressed against the base material. A metal that forms a metal film on the surface of the substrate by applying a voltage between the substrate and the substrate to reduce metal ions derived from the metal solution contained in the solid electrolyte membrane A film forming apparatus,
The solution chamber is formed by a housing having a storage space for storing the metal solution, the storage space having an opening opened to the base, and an elastic body attached to the opening of the housing. The solid electrolyte membrane is attached to the solution chamber via the elastic body,
The elastic body extends to the outside of the solution chamber along the pressing direction so that it can be compressed and deformed in the pressing direction of the base material when the solid electrolyte membrane is pressed against the base material. A metal film forming apparatus characterized by the above.

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