Film Forming Apparatus and Film Forming Method

Abstract

To provide a deposition apparatus and a deposition method that can suppress evaporation of a plating solution adhered to a polymer electrolyte.SOLUTION: A deposition apparatus 1 is an apparatus for depositing a metallic film derived from metallic ions in a plating solution onto the surface of a substrate 12 by applying voltage in a state in which a polymer electrolyte 13 is in contact with a substrate 12. The deposition apparatus 1 comprises: a container moving device 18 for moving a container 14 so as to become one state of a deposition state in which the polymer electrolyte 13 performs a deposition in contact with the substrate 12 and a non-deposition state in which the polymer electrolyte 13 is detached from the substrate 12 to the other state; a heater 22 for heating the plating solution; and a polymer electrolyte moving device 23 for, in the non-deposition state, moving the polymer electrolyte 13 so as to be detached from the substrate 12 or to again cover an opening part 141 of the container 14.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a film forming apparatus and a film forming method, and particularly to a film forming apparatus and a film forming method suitable for the solid phase electrolysis method.

Background Art

[0002] As a film forming apparatus suitable for the solid phase electrolysis method, for example, as described in Patent Document 1 below, an electrolyte membrane disposed between a base material as an anode and a cathode, an anode and a plating solution are accommodated, and an opening opened on the base material side is covered with the electrolyte membrane And a power supply unit that applies a voltage between the anode and the base material, and a metal film derived from metal ions in the plating solution is formed on the surface of the base material by applying a voltage.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When forming a film by the solid phase electrolysis method, in order to increase the film forming speed, the plating solution is usually heated to 30 to 90 ° C. to form a film. When forming a film continuously on a plurality of base materials, the base material is exchanged while maintaining the container at a predetermined temperature. When the base material is exchanged, the heat from the container continues to be transferred to the electrolyte membrane, so that the electrolyte membrane reaches the same temperature as the container. As a result, the plating solution attached to the electrolyte membrane evaporates, the electrolyte membrane becomes dry, and plating components (metals) may precipitate inside and on the surface of the electrolyte membrane. When a film is formed again on the surface of the base material exchanged in a state where the plating component is deposited on the electrolyte membrane, pits and pinholes may occur in the formed metal film, which may affect the quality of the metal film.

[0005] The present invention has been made to solve such technical problems, and an object thereof is to provide a film forming apparatus and a film forming method capable of suppressing evaporation of the plating solution adhering to the electrolyte membrane.

Means for Solving the Problems

[0006] The film forming apparatus according to the present invention includes an anode, an electrolyte membrane disposed between the anode and a base material that is a cathode, a container that houses the anode and the plating solution and has an opening on the base material side covered with the electrolyte membrane, and a power supply unit that applies a voltage between the anode and the base material. The film forming apparatus is a film forming apparatus that forms a metal film derived from metal ions in the plating solution on the surface of the base material by applying the voltage in a state where the electrolyte membrane is in contact with the base material. The film forming apparatus further includes a container moving device that moves the container so that the electrolyte membrane changes from one of a film forming state in which the electrolyte membrane is in contact with the base material and a non-film forming state in which the electrolyte membrane is separated from the base material to the other state, a heating device that heats the plating solution, and an electrolyte membrane moving device that moves the electrolyte membrane so as to separate the electrolyte membrane from the container or cover the opening of the container with the separated electrolyte membrane in the non-film forming state.

[0007] In the film forming apparatus according to the present invention, since the electrolyte membrane moving device that moves the electrolyte membrane so as to separate the electrolyte membrane from the container or cover the opening of the container with the separated electrolyte membrane is provided in the non-film forming state, when replacing the formed base material with the base material to be film formed next, heat transfer from the container to the electrolyte membrane can be suppressed by separating the electrolyte membrane from the container using the electrolyte membrane moving device. As a result, since the temperature of the electrolyte membrane decreases, evaporation of the plating solution adhering to the electrolyte membrane can be suppressed, and drying of the electrolyte membrane can be prevented.

[0008] In the film forming apparatus according to the present invention, it is preferable to include a supply device that supplies the plating solution to the container and supplies gas to the container so that the plating solution is discharged from the container. In this way, when discharging the plating solution from the container, the plating solution can be reliably discharged by supplying gas to the container using the supply device. At this time, heat from the container tries to transfer to the electrolyte membrane, but by separating the electrolyte membrane from the container with the electrolyte membrane moving device, heat transfer from the container can be suppressed, so evaporation of the plating solution adhering to the electrolyte membrane can be suppressed.

[0009] In the film forming apparatus according to the present invention, in a state where the electrolyte membrane is separated from the container, it is preferable to include a heat absorbing member that contacts the electrolyte membrane from the substrate side and absorbs the heat of the electrolyte membrane, or a cooling device that contacts the electrolyte membrane from the substrate side and cools the electrolyte membrane. In this way, by absorbing the heat of the electrolyte membrane using the heat absorbing member or cooling the electrolyte membrane using the cooling device, the temperature of the electrolyte membrane can be further lowered, so evaporation of the plating solution adhering to the electrolyte membrane can be further suppressed.

[0010] Further, the film forming method according to the present invention is a film forming method in which a voltage is applied between an anode and the substrate that is a cathode in a state where an electrolyte membrane in contact with a plating solution containing metal ions is in contact with the substrate, and a metal film derived from the metal ions contained in the electrolyte membrane is formed on the surface of the substrate. The method includes a step of contacting the electrolyte membrane covering the opening formed in the container with the substrate disposed opposite to the electrolyte membrane, and then applying a voltage between the anode and the substrate with the plating solution contained in the container to form the metal film; a step of discharging the plating solution contained in the container from the container after forming the metal film; a step of separating the container from the substrate after discharging the plating solution from the container; a step of separating the electrolyte membrane from the container after separating the container from the substrate; and a step of replacing the formed substrate with the substrate to be next formed in a state where the electrolyte membrane is separated from the container.

[0011] In the film forming method according to the present invention, after separating the container from the substrate, since the step of pulling the electrolyte membrane away from the container is included, before the step of exchanging the formed substrate with the substrate to be film formed next, by pulling the electrolyte membrane away from the container, heat transfer from the container to the electrolyte membrane can be suppressed. As a result, the temperature of the electrolyte membrane can be lowered, so that evaporation of the plating solution adhering to the electrolyte membrane can be suppressed, and drying of the electrolyte membrane can be prevented.

[0012] In the film forming method according to the present invention, it is preferable to further include a step of lowering the temperature of the electrolyte membrane with a heat absorbing member or a cooling device between the step of pulling the electrolyte membrane away from the container and the step of exchanging the formed substrate with the substrate to be film formed next. In this way, by lowering the temperature of the electrolyte membrane with a heat absorbing member or a cooling device, evaporation of the plating solution adhering to the electrolyte membrane can be further suppressed.

Effect of the Invention

[0013] According to the present invention, evaporation of the plating solution adhering to the electrolyte membrane can be suppressed.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0015] Hereinafter, embodiments of a film forming apparatus and a film forming method according to the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and the overlapping description thereof will be omitted.

[0016] [First Embodiment] The film forming apparatus 1 of the present embodiment is a plating apparatus for forming a metal film (in other words, coating) on the surface of a base material 12 using the solid phase electrodeposition method. As shown in FIG. 1, the film forming apparatus 1 includes an anode 11, a base material 12 as a cathode, an electrolyte membrane 13 disposed between the anode 11 and the base material 12, a container 14 that houses the anode 11 and the plating solution, a mounting table 15 that is disposed below the container 14 and for mounting the base material 12, and a power supply unit 16 that applies a voltage between the anode 11 and the base material 12.

[0017] The anode 11 is formed in a flat plate shape from a metal material and is built in the container 14 in a state where it can contact the plating solution filled in the container 14. The anode 11 is electrically connected to the positive electrode of the power supply unit 16 via a conducting wire or the like. This anode 11 may be either a soluble anode made of the same material (for example, copper) as the metal film formed on the base material 12 or an anode made of a material (for example, titanium) that is insoluble in the plating solution.

[0018] The base material 12 is, for example, a plate-shaped member. The material of the base material 12 may be made of a metal material such as copper, silver, gold, nickel, aluminum, or iron, or a metal layer made of the above-described metal may be coated on the surface of resin, ceramics, or the like. The base material 12 is electrically connected to the negative electrode of the power supply unit 16 via a conductive member 17 provided on the mounting table 15.

[0019] The electrolyte membrane 13 is a so-called solid electrolyte membrane and has a certain flexibility. The electrolyte membrane 13 is brought into contact with the plating solution accommodated in the container 14, so that the metal ions contained in the plating solution are impregnated (contained) therein. Then, when a voltage is applied, a metal derived from the metal ions is deposited on the surface of the cathode (substrate 12).

[0020] The thickness of the electrolyte membrane 13 is, for example, 5 to 200 μm. Examples of the material of the electrolyte membrane 13 include fluorine-based resins such as Nafion (registered trademark) manufactured by DuPont, hydrocarbon-based resins, polyamic acid resins, and resins having an ion exchange function such as Selemion (CMV, CMD, CMF series) manufactured by Asahi Glass Co., Ltd.

[0021] The container 14 is made of a material insoluble in the plating solution and is formed to have a liquid accommodation space S for accommodating the plating solution therein. Specifically, the container 14 has an opening 141 that opens downward (i.e., on the side of the substrate 12), a top plate portion 142 disposed on the opposite side of the opening 141, and a side wall portion 143 that extends downward from the periphery of the top plate portion 142. The anode 11 described above is fitted into the bottom surface of the top plate portion 142. The electrolyte membrane 13 is disposed so as to cover the opening 141 at a position facing the anode 11 of the container 14. The space surrounded by the anode 11, the side wall portion 143, and the electrolyte membrane 13 becomes the above-described liquid accommodation space S.

[0022] That is, in the container 14 of the present embodiment, the anode 11 and the electrolyte membrane 13 are spaced apart from each other and are in a non-contact state. However, when the liquid accommodation space S is filled with the plating solution, the anode 11 and the electrolyte membrane 13 will contact each other through the plating solution.

[0023] Further, the container 14 is provided with a supply passage 14a through which the plating solution is supplied and a discharge passage 14b through which the plating solution is discharged. The container 14 is connected to the tank 19 and the pump 20 via pipes. Then, the plating solution sent out from the tank 19 by the pump 20 flows into the liquid storage space S from the supply passage 14a, is discharged from the discharge passage 14b, and returns to the tank 19. Further, a pressure regulating valve 21 is provided on the downstream side of the discharge passage 14b, and the plating solution in the container 14 can be pressurized at a predetermined pressure by the pressure regulating valve 21 and the pump 20.

[0024] Also, a three-way valve 24 is provided between the tank 19 and the pump 20. The three-way valve 24 has a passage for taking in air in addition to a passage communicating with the tank 19 and a passage communicating with the pump 20. The tank 19, the pump 20, and the three-way valve 24 constitute the "supply device" described in the claims. That is, in the three-way valve 24, when the passage communicating with the tank 19 and the passage communicating with the pump 20 communicate, the plating solution stored in the tank 19 is supplied to the liquid storage space S of the container 14 by driving the pump 20. On the other hand, in the three-way valve 24, when the passage for taking in air and the passage communicating with the tank 19 communicate, air is supplied to the liquid storage space S of the container 14 by driving the pump 20. The supply of air to the liquid storage space S is used to discharge the plating solution in the liquid storage space S. Here, instead of air, other gases stored in a gas cylinder connected via the three-way valve 24 may be used.

[0025] Furthermore, the supply passage 14a of the container 14 is connected to an open passage that is opened to the atmosphere via a shut-off valve 25.

[0026] The plating solution is a solution that contains the metal of the metal film to be formed in an ionic state, and examples of such metal include copper, nickel, silver, or tin. The plating solution is an aqueous solution in which these metals are dissolved (ionized) with an acid such as nitric acid, phosphoric acid, succinic acid, sulfuric acid, or pyrophosphoric acid. For example, when the metal is nickel, examples of the plating solution include aqueous solutions of nickel nitrate, nickel phosphate, nickel succinate, nickel sulfate, nickel pyrophosphate, or nickel sulfamate. Further, when the metal is copper, examples of the plating solution include aqueous solutions containing copper sulfate, copper pyrophosphate, or the like.

[0027] The mounting table 15 is made of a conductive material and is disposed below the container 14 so that the base material 12 to be mounted faces the electrolyte membrane 13. A conductive member 17 is provided on the mounting table 15. The conductive member 17 is formed, for example, by bending a metal plate into a Z-shaped cross section. One end portion (the lower end portion in FIGS. 1 and 2) of the conductive member 17 is in contact with the mounting table 15, and the other end portion (the upper end portion in FIGS. 1 and 2) is in contact with the upper surface of the base material 12. Note that the conductive member 17 is detachable from the base material 12.

[0028] Furthermore, the film forming apparatus 1 of the present embodiment includes a container moving device 18 that moves the container 14 so that the electrolyte membrane 13 changes from one of a film forming state in which the electrolyte membrane 13 is in contact with the base material 12 to form a film and a non-film forming state in which the electrolyte membrane 13 is separated from the base material 12 to the other state, a heating device 22 that heats the plating solution, and an electrolyte membrane moving device 23 that moves the electrolyte membrane 13 so that in the non-film forming state, the electrolyte membrane 13 is pulled away from the container 14 or the pulled-away electrolyte membrane 13 covers the opening 141 of the container 14 again.

[0029] The container moving device 18 is disposed, for example, above the container 14 and is composed of, for example, a hydraulic or pneumatic cylinder, an electric actuator, a linear guide, a motor, and the like. By driving the container moving device 18, the container 14 can be brought closer to the mounting table 15 so that the electrolyte membrane 13 disposed in the container 14 contacts the base material 12 mounted on the mounting table 15. Further, by driving the container moving device 18, the container 14 can be separated from the mounting table 15 so that the electrolyte membrane 13 in contact with the base material 12 is separated from the base material 12.

[0030] The heating device 22 is not particularly limited in its configuration and location as long as it can heat the plating solution. The heating device 22 may be, for example, at least one of a heater built in the top plate portion 142 of the container 14, a heater built in the side wall portion 143 of the container 14, an immersion heater disposed inside the tank 19, a heater disposed at the lower portion of the tank 19, and a heater built in the mounting table 15. In the present embodiment, the heating device 22 is, for example, a plurality of heaters built in the side wall portion 143 of the container 14, and heats the plating solution accommodated in the liquid accommodation space S through the side wall portion 143 to a predetermined temperature. By heating the plating solution to a predetermined temperature in this way, the film formation rate of the metal film can be increased.

[0031] In the non-film formation state, the electrolyte membrane moving device 23 is provided so that the electrolyte membrane 13 can be brought into contact with and separated from the container 14 while holding the electrolyte membrane 13. As shown in FIGS. 1 to 3, the electrolyte membrane moving device 23 of the present embodiment includes four linear guides 231 attached to the outer wall of the side wall portion 143 of the container 14, an electrolyte membrane holding frame 233 that holds the electrolyte membrane 13 from below and can move up and down along the linear guides 231, and a motor 232 that rotates a ball screw (not shown) to move the electrolyte membrane holding frame 233 up and down. The electrolyte membrane holding frame 233 is formed in a rectangular frame shape and is larger than the base material 12 so as not to interfere with the contact between the electrolyte membrane 13 and the base material 12 during film formation (see FIG. 3).

[0032] In the electrolyte membrane moving device 23, for example, when the motor 232 rotates forward, the ball screw shaft rotates forward, and accordingly, the electrolyte membrane holding frame 233 descends along the linear guide 231. Therefore, the electrolyte membrane 13 held by the electrolyte membrane holding frame 233 moves away from the container 14 (see FIG. 2). On the other hand, when the motor 232 rotates reversely, the ball screw shaft rotates reversely, and accordingly, the electrolyte membrane holding frame 233 ascends along the linear guide 231. Therefore, the electrolyte membrane 13 held by the electrolyte membrane holding frame 233 approaches the container 14. The electrolyte membrane 13 finally ascends to a position covering the opening 141 of the container 14 (see FIG. 1).

[0033] Note that the electrolyte membrane moving device 23 is not limited to the above-described structure, and may be configured to include, for example, a hydraulic or pneumatic cylinder, an electric actuator, or the like.

[0034] In the film forming apparatus 1 of the present embodiment, in a non-film forming state, an electrolyte membrane moving device 23 that moves the electrolyte membrane 13 is provided so as to separate the electrolyte membrane 13 from the container 14 or cover the opening 141 of the container 14 with the separated electrolyte membrane 13 again. Therefore, when replacing the formed substrate 12 with the substrate 12 on which film formation is to be performed next, heat transfer from the container 14 to the electrolyte membrane 13 (more specifically, from the side wall portion 143 of the container 14 to the electrolyte membrane 13) can be suppressed by separating the electrolyte membrane 13 from the container 14 using the electrolyte membrane moving device 23. As a result, since the temperature of the electrolyte membrane 13 decreases, evaporation of the plating solution adhering to the electrolyte membrane 13 can be suppressed, and drying of the electrolyte membrane 13 can be prevented. Therefore, when forming a film again on the surface of the new substrate 12 replaced using the electrolyte membrane 13, film formation defects caused by precipitation of components from the plating solution due to drying can be prevented.

[0035] Hereinafter, the film forming method of the present embodiment will be described with reference to FIG. 4. The film forming method of the present embodiment assumes a case where film formation is continuously performed on a plurality of substrates 12 using the above-described film forming apparatus 1. Further, in the following description, it is assumed that the electrolyte membrane 13 is held by the electrolyte membrane holding frame 233 of the electrolyte membrane moving device 23.

[0036] First, in step S101, the substrate 12 on which a film is to be formed is placed on the mounting table 15.

[0037] In step S102 following step S101, using the electrolyte membrane moving device 23, the electrolyte membrane 13 held by the electrolyte membrane holding frame 233 is brought close to the container 14 so as to cover the opening 141 of the container 14.

[0038] In step S103 following step S102, using the container moving device 18, the container 14 is lowered so that the electrolyte membrane 13 covering the opening 141 comes into contact with the substrate 12 placed on the mounting table 15.

[0039] In step S104 following step S103, the pump 20 is driven to send the plating solution stored in the tank 19 to the container 14. As a result, the plating solution stored in the tank 19 is supplied from the supply flow path 14a of the container 14 to the liquid storage space S of the container 14. Then, receiving the liquid pressure of the plating solution, the electrolyte membrane 13 presses the substrate 12.

[0040] In step S105 following step S104, voltage application is started. That is, using the power supply unit 16, a voltage is applied between the anode 11 and the substrate 12 which is the cathode. When the voltage is applied, a metal derived from metal ions is deposited on the surface of the substrate 12 which is the cathode, and a metal film is formed on the surface of the substrate 12.

[0041] And when a metal film with a desired film thickness is formed, the voltage application is terminated (see step S106).

[0042] Note that steps S102 to S106 constitute the "step of forming a metal film" described in the claims.

[0043] In step S107 following step S106, compressed air is supplied to the liquid storage space S of the container 14 using the three-way valve 24 and the pump 20, and the plating solution stored in the liquid storage space S is discharged. That is, step S107 is the "step of discharging the plating solution from the container" described in the claims.

[0044] After discharging the plating solution stored in the liquid storage space S, the inside of the container 14 is opened to the atmosphere. By doing so, the compressed air supplied to the liquid storage space S can be released to the atmosphere, and the temperature of the electrolyte membrane 13 covering the opening 141 of the container 14 can be lowered.

[0045] In step S108 following step S107, the container 14 is lifted using the container moving device 18 so that the electrolyte membrane 13 in contact with the base material 12 separates from the base material 12. As a result, the container 14 is separated from the base material 12. That is, step S108 is the "step of separating the container from the base material" described in the claims.

[0046] In step S109 following step S108, the electrolyte membrane 13 is pulled away from the container 14 using the electrolyte membrane moving device 23. That is, step S109 is the "step of pulling the electrolyte membrane away from the container" described in the claims.

[0047] In step S110 following step S109, the formed base material 12 is removed from the mounting table 15. When step S110 ends, next, the base material 12 to be formed is placed on the mounting table 15 (step S101). Steps S110 and S101 constitute the "step of replacing the formed base material with the base material to be formed next" described in the claims. As a result, the above-described steps S101 to S110 are repeatedly executed.

[0048] In the film formation method of the present embodiment, before replacing the formed substrate 12 with the substrate 12 on which film formation is to be performed next, by separating the electrolyte membrane 13 from the container 14, heat transfer from the container 14 to the electrolyte membrane 13 (more specifically, from the side wall portion 143 of the container 14 to the electrolyte membrane 13) can be suppressed. As a result, the temperature of the electrolyte membrane 13 can be lowered, evaporation of the plating solution adhering to the electrolyte membrane 13 can be suppressed, and drying of the electrolyte membrane 13 can be prevented. Therefore, when forming a film again on the surface of the substrate 12 replaced with the electrolyte membrane 13, film formation defects caused by precipitation of components from the plating solution due to drying can be prevented.

[0049] [Second Embodiment] Next, a second embodiment of the film forming apparatus will be described with reference to FIGS. 5 and 6. The film forming apparatus 1A of the present embodiment is different from the above-described first embodiment in that it further includes a heat absorbing member 26. Below, only the differences will be described.

[0050] As shown in FIGS. 5 and 6, the heat absorbing member 26 has, for example, a flat plate shape and is formed larger than the electrolyte membrane 13. The heat absorbing member 26 is held by a pair of left and right frame members 27 slidably provided in the front-rear direction (see the arrow direction in FIG. 5) orthogonal to the vertical direction.

[0051] More specifically, the frame member 27 has a long shape and is formed to have a concave groove 271 for fitting the heat absorbing member 26. Examples of the material used for the frame member 27 include metal materials such as aluminum and hard resin materials. Then, the pair of left and right frame members 27 are arranged below the linear guide 231 and the electrolyte membrane holding frame 233 of the electrolyte membrane moving device 23 with the concave grooves 271 facing each other. In this way, the heat absorbing member 26 held by the frame member 27 can be brought into contact with the electrolyte membrane 13 from the substrate 12 side (in other words, from below the electrolyte membrane 13).

[0052] The heat-absorbing member 26 is made of, for example, a metal material with high thermal conductivity such as copper or aluminum, a base material or a material coated on the base material that is difficult to be ionized, a heat-conducting sheet such as a graphite sheet or a carbon fiber sheet, or is formed of aluminum nitride or the like.

[0053] According to the film forming apparatus 1A of the present embodiment, in addition to obtaining the same operational effects as those of the above-described first embodiment, since the heat-absorbing member 26 is further provided, in a state where the electrolyte membrane 13 is separated from the container 14, the heat of the electrolyte membrane 13 can be absorbed by bringing the heat-absorbing member 26 into contact with the electrolyte membrane 13 from below the electrolyte membrane 13. Thereby, since the temperature of the electrolyte membrane 13 can be further lowered, evaporation of the plating solution adhering to the electrolyte membrane 13 can be further suppressed.

[0054] Note that the shape of the heat-absorbing member 26 is not limited to the above-described flat plate shape. For example, as shown in FIG. 7, a standing peripheral wall portion 261 that stands upward may be further formed so as to be fitted into the electrolyte membrane holding frame 233 from below the electrolyte membrane 13. In this way, the heat of the electrolyte membrane 13 can be absorbed not only from below the electrolyte membrane 13 but also from the four peripheries of the electrolyte membrane 13 via the electrolyte membrane holding frame 233, so that evaporation of the plating solution adhering to the electrolyte membrane 13 can be further suppressed. In this case, the heat-absorbing member 26 is configured to be slidable in the front-rear direction by the frame member 27 and also movable in the vertical direction.

[0055] Further, in the present embodiment, instead of the heat-absorbing member 26, a cooling device such as a heat sink or a water-coolable chiller may be used. The cooling device is provided so as to be supported by the frame member 27 in the same manner as the heat-absorbing member 26, for example, so as to cool the electrolyte membrane 13 in a state of being in contact with the electrolyte membrane 13 from below. In this way, the same operational effects as those obtained when the heat-absorbing member 26 is used can be obtained.

[0056] Note that in the film formation method of the second embodiment, a step of lowering the temperature of the electrolyte membrane 13 with the heat absorption member 26 is added between step S109 (step of separating the electrolyte membrane from the container) and step S110 (step of removing the formed substrate) of the first embodiment, and a step of removing the heat absorption member 26 is added between step S101 (step of placing the substrate) and step S102 (step of covering the opening of the container with the electrolyte membrane). According to the film formation method of the present embodiment, evaporation of the plating solution adhering to the electrolyte membrane 13 can be further suppressed.

[0057] [Third Embodiment] Hereinafter, a third embodiment of the film forming apparatus will be described with reference to FIG. 8. The film forming apparatus 1B of the present embodiment is different from the above-described first embodiment in that the electrolyte membrane moving device 23 is not arranged on the side of the container 14 but on the side of the mounting table 15. Hereinafter, only the differences will be described.

[0058] As shown in FIG. 8, the electrolyte membrane moving device 23 includes four linear guides 231 attached to the outer wall of the mounting table 15, an electrolyte membrane holding frame 233 that holds the electrolyte membrane 13 from below and can move up and down along the linear guide 231, and a motor (not shown) that rotates a ball screw to move the electrolyte membrane holding frame 233 up and down. The electrolyte membrane holding frame 233 is formed in a rectangular frame shape and is larger than both the substrate 12 and the electrolyte membrane 13 so as not to interfere with the contact between the electrolyte membrane 13 and the substrate 12 during film formation.

[0059] According to the film forming apparatus 1B of the present embodiment, the same operational effects as those of the above-described first embodiment can be obtained.

[0060] [Examples and Comparative Examples] In order to confirm the effect of suppressing the evaporation of the plating solution adhering to the electrolyte membrane, the present inventors further verified it by heat transfer analysis. Specifically, using the thermal circuit network method, the temperature of the peripheral portion of the electrolyte membrane (that is, the portion in contact with the side wall portion of the container) and the temperature of the central portion of the electrolyte membrane (that is, the portion corresponding to the center of the opening of the container) were calculated respectively.

[0061] Here, it is assumed that a metal film is formed using a plating solution heated to 70°C by a heating device. Specifically, the calculation conditions were set such that the temperature of the container was 70°C, and the temperature of the air (atmosphere) in the liquid storage space S after discharging the plating solution was set to 40°C. After maintaining such a state for 60 seconds, the temperatures of the peripheral portion and the central portion of the electrolyte membrane described above were calculated respectively. The calculated results are shown in Table 1.

[0062] Also, Example 1 shown in Table 1 is an example using the film forming apparatus 1 of the first embodiment, and Example 2 shown in Table 2 is an example using the film forming apparatus 1A (equipped with the heat absorbing member 26) of the second embodiment. Furthermore, for comparison, temperature calculation was performed under the same conditions using a film forming apparatus without countermeasures (that is, a conventional film forming apparatus not provided with the electrolyte membrane moving device 23).

[0063]

Table 1

[0064] As shown in Table 1, in the comparative example without countermeasures, the temperature of the peripheral portion of the electrolyte membrane was 70°C. This is because the peripheral portion of the electrolyte membrane is in contact with the side wall portion 143 of the container 14 and continues to be heated by the heat from the side wall portion 143, so the temperature does not drop. Also, the temperature of the central portion of the electrolyte membrane was almost the same as the temperature of the air around the container 14, which was 40.2°C. This is because the central portion of the electrolyte membrane receives heat transfer from the peripheral portion and it is difficult for the temperature to drop.

[0065] On the other hand, in Example 1, the temperature of the peripheral portion of the electrolyte membrane was 35°C, and the temperature of the central portion of the electrolyte membrane was 25°C (substantially the same as room temperature). From the results of Example 1 and the comparative example, it was shown that according to the film forming apparatus 1 of the first embodiment, heat transfer from the container to the electrolyte membrane can be suppressed, and the evaporation of the plating solution adhering to the electrolyte membrane can be suppressed.

[0066] In Example 2, the temperature at the peripheral edge of the electrolyte membrane was 25°C (substantially the same as room temperature), and the temperature at the central portion of the electrolyte membrane was 25°C (substantially the same as room temperature). From the results of Example 1 and Example 2, it was shown that by providing the heat-absorbing member, the temperature of the electrolyte membrane can be further lowered, and the evaporation of the plating solution adhering to the electrolyte membrane can be further suppressed.

[0067] As described above, the embodiments of the present invention have been described in detail. However, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the spirit of the present invention described in the claims.

Explanation of Reference Numerals

[0068] 1, 1A, 1B: Film-forming apparatus, 11: Anode, 12: Substrate, 13: Electrolyte membrane, 14: Container, 14a: Supply flow path, 14b: Discharge flow path, 15: Mounting table, 16: Power supply unit, 17: Conductive member, 18: Container moving device, 19: Tank, 20: Pump, 21: Pressure regulating valve, 22: Heating device, 23: Electrolyte membrane moving device, 24: Three-way valve, 25: Partition valve, 26: Heat-absorbing member, 27: Frame member, 141: Opening, 142: Top plate portion, 143: Side wall portion, 231: Linear guide, 232: Motor, 233: Electrolyte membrane holding frame, 261: Upright peripheral wall portion, 271: Concave groove

Claims

1. An anode, An electrolyte membrane disposed between the anode and a substrate serving as the cathode and positioned above the substrate, A container that has a top plate portion into which the anode is fitted, a side wall portion extending downward from the periphery of the top plate portion, and an opening that opens to the substrate side and is covered by the electrolyte membrane, and that houses a plating solution, A power supply unit that applies a voltage between the anode and the substrate, and A film forming apparatus that forms a metal film derived from metal ions in the plating solution on the surface of the substrate by applying the voltage with the electrolyte membrane in contact with the substrate, The film forming apparatus, A container moving device that moves the container so that the electrolyte membrane changes from one of a film forming state in which the electrolyte membrane is in contact with the substrate and a non-film forming state in which the electrolyte membrane is separated from the substrate to the other state, A heating device including a plurality of heaters built into the side wall portion and heating the plating solution housed in the container through the side wall portion, An electrolyte membrane moving device that moves the electrolyte membrane in the vertical direction so as to pull the electrolyte membrane away from the container and then cover the opening of the container again with the pulled-away electrolyte membrane, and Further includes, The electrolyte membrane moving device is characterized in that, in the non-film forming state, the electrolyte membrane is pulled away from the container so as to suppress heat transfer from the container to the electrolyte membrane.

2. The film forming apparatus according to claim 1, further comprising a supply device that supplies the plating solution to the container and supplies gas to the container so that the plating solution is discharged from the container.

3. The film forming apparatus according to claim 1 or 2, further comprising a heat absorbing member that contacts the electrolyte membrane from the substrate side and absorbs heat of the electrolyte membrane, or a cooling device that contacts the electrolyte membrane from the substrate side and cools the electrolyte membrane, in a state where the electrolyte membrane is pulled away from the container.

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