Metal film deposition apparatus

Abstract

The present invention provides a metal film deposition apparatus that can accurately deposit a metal film in a predetermined pattern using a masking material having a mask portion made of rubber material. [Solution] The masking material 60 of the film deposition apparatus 1 has a through-hole 68 and a mask portion 65 made of rubber material. Between the electrolyte membrane 13 and the mask portion 65, an insulating porous plate 30 with multiple pores through which the plating solution L passes is arranged to cover the through-hole 68.

Description

Technical Field

[0001] The present invention relates to a film forming apparatus for a metal film.

Background Art

[0002] As this type of technology, for example, Patent Document 1 proposes a film forming apparatus for a metal film provided with a masking material for forming a metal film with a predetermined pattern on the surface of a substrate by electrolytic plating. This masking material has a mask portion in which through portions corresponding to a predetermined pattern are formed. The mask portion is made of a rubber material.

[0003] When forming a metal film, the mask portion of the masking material is sandwiched between the electrolyte film and the substrate, and the electrolyte film is pressed toward the substrate by the hydraulic pressure of the plating solution. In this pressed state, a voltage is applied between the anode and the substrate to form a metal film on the surface of the substrate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when the mask portion of the masking material shown in Patent Document 1 is made of a rubber material, the mask portion may be non-uniformly compressed and deformed when it is pressed by the electrolyte film during film formation. This makes it difficult to form a metal film with a predetermined pattern corresponding to the shape of the through portion.

[0006] The present invention has been made in view of such points, and an object thereof is to provide a film forming apparatus for a metal film that can accurately form a metal film with a predetermined pattern using a masking material having a mask portion made of a rubber material. [Means for solving the problem]

[0007] In view of the above problems, the metal film deposition apparatus according to the present invention is a metal film deposition apparatus that deposits a metal film of a predetermined pattern on the surface of a substrate by electroplating. The deposition apparatus comprises a container having an opening formed at a position facing the substrate and containing a plating solution, with the opening covered by an electrolyte membrane; a pressing mechanism that presses the substrate with the electrolyte membrane by the liquid pressure of the plating solution contained in the container; an anode disposed inside the container at a position facing the electrolyte membrane; and a masking material disposed between the electrolyte membrane and the substrate, with the predetermined pattern formed thereon. The masking material has the formed thereon portion and a mask portion made of rubber material. Between the electrolyte membrane and the mask portion, a porous plate having a plurality of pores through which the plating solution passes is disposed so as to cover the thereon portion.

[0008] In one embodiment, the mask portion comprises a first portion facing the electrolyte membrane and a second portion facing the substrate. The masking material has a mesh portion woven with wire, the mesh portion being positioned between the first portion and the second portion and holding the first portion and the second portion.

[0009] In a further embodiment, the masking material includes a frame that secures the periphery of the mesh portion. The porous plate is positioned between the electrolyte membrane and the mask portion in a manner that is not constrained by the frame.

[0010] In another embodiment, the mask portion is fixed to the surface of the porous plate facing the substrate. A mesh woven with wire is attached to the periphery of the porous plate so as to surround it. The outer edge of the mesh is fixed to the frame.

[0011] In yet another embodiment, the porous plate is made of chemically strengthened glass, and the pores are through holes formed along the thickness direction of the porous plate. [Effects of the Invention]

[0012] According to the present invention, a metal film with a predetermined pattern can be accurately formed using a masking material having a mask portion made of rubber material. [Brief explanation of the drawing]

[0013] [Figure 1] This is a schematic cross-sectional view showing an example of a metal film deposition apparatus according to an embodiment of the present invention. [Figure 2] Figure 1 is a schematic perspective view showing a porous plate, a masking material, and a substrate on which a metal film has been deposited. [Figure 3] This is a schematic cross-sectional view illustrating the film deposition process using the film deposition apparatus shown in Figure 1. [Figure 4] Figure 3 is a schematic cross-sectional view illustrating the deposition of a metal film using the deposition apparatus shown. [Figure 5] (a) is a schematic cross-sectional view of a film deposition apparatus according to a modified example of the film deposition apparatus shown in Figure 4, and (b) is a schematic cross-sectional view of a film deposition apparatus according to another modified example. [Figure 6] Figure 2 is a schematic perspective view showing a modified example of the masking material. [Figure 7] (a) is a schematic cross-sectional view of a film deposition apparatus using the masking material shown in Figure 6, and (b) is a schematic cross-sectional view of a film deposition apparatus according to another modified example. [Modes for carrying out the invention]

[0014] A metal film deposition apparatus 1 according to an embodiment of the present invention will now be described. Figure 1 is a schematic cross-sectional view showing an example of a metal film deposition apparatus according to an embodiment of the present invention.

[0015] As shown in FIG. 1, the film forming apparatus 1 is a film forming apparatus that forms a metal film F of a predetermined pattern P on a substrate B by electrolytic plating with a masking material 60 sandwiched between an electrolyte film 13 and the substrate B. Specifically, the film forming apparatus 1 includes an anode 11, an electrolyte film 13, and a power source 14 that applies a voltage between the anode 11 and the substrate B.

[0016] The film forming apparatus 1 includes a container 15 that houses the anode 11 and the plating solution L, a mounting table 40 on which the substrate B is placed, and a masking material 60. During film formation, the masking material 60 is placed on the mounting table 40 together with the substrate B. The electrolyte film 13 is disposed between the masking material 60 and the anode 11.

[0017] The film forming apparatus 1 includes a linear actuator 70 that raises and lowers the container 15. In the present embodiment, for the sake of convenience of explanation, it is assumed that the electrolyte film 13 is disposed below the anode 11, and further, the masking material 60 and the substrate B are disposed below it. However, if a metal film F can be formed on the surface of the substrate B, it is not limited to this positional relationship.

[0018] The substrate B functions as a cathode. The substrate B is a plate-shaped substrate. In the present embodiment, the substrate B is a rectangular substrate. Among the surfaces of the substrate B, the opposing surface that faces the electrolyte film 13 (screen mask 62) is a film forming surface that functions as a cathode. As long as it functions as a cathode (i.e., a conductive surface), the material of the substrate B is not particularly limited. The substrate B may be made of a metal material such as aluminum or copper, for example.

[0019] In the present embodiment, as shown in FIG. 2, since a pattern (wiring pattern) P is formed from the metal film F, a substrate in which an underlayer Bb such as copper is formed on the surface of an insulating substrate Ba such as resin is used as the substrate B. In this case, after the metal film F is formed, the underlayer Bb other than the portion where the metal film F is formed is removed by etching or the like. Thereby, the pattern P by the metal film F can be formed on the surface of the insulating substrate Ba.

[0020] The anode 11 is, for example, a non-porous (e.g., dense) anode made of the same metal as the metal of the metal film. The anode 11 has a block-like or flat plate-like shape. Examples of the material of the anode 11 include copper and the like. The anode 11 dissolves when the voltage of the power supply 14 is applied. However, when forming a film only with the metal ions of the plating solution L, the anode 11 is an anode insoluble in the plating solution L. The anode 11 is electrically connected to the positive electrode of the power supply 14. The negative electrode of the power supply 14 is electrically connected to the base material B via the mounting table 40.

[0021] The plating solution L is a solution containing the metal of the metal film to be formed in an ionic state. Examples of the metal include copper, nickel, gold, silver, or iron. The plating solution L is a solution in which these metals are dissolved (ionized) with an acid such as nitric acid, phosphoric acid, succinic acid, sulfuric acid, or pyrophosphoric acid. Examples of the solvent of the solution include water and alcohol. For example, when the metal is copper, examples of the plating solution L include an aqueous solution containing copper sulfate, copper pyrophosphate, and the like.

[0022] The electrolyte membrane 13 is a membrane that can be impregnated (contain) metal ions together with the plating solution L by contacting with the plating solution L. The electrolyte membrane 13 is a flexible membrane. When a voltage is applied by the power supply 14, the material of the electrolyte membrane 13 is not particularly limited as long as the metal ions of the plating solution L can move to the base material B side. Examples of the material of the electrolyte membrane 13 include resins having an ion exchange function such as fluorine-based resins such as Nafion (registered trademark) manufactured by DuPont. The film thickness of the electrolyte membrane 13 is preferably in the range of 20 μm to 200 μm. More preferably, the film thickness is in the range of 20 μm to 60 μm.

[0023] The container 15 is made of a material insoluble in the plating solution L. The container 15 has a containment space 15a for containing the plating solution L. The anode 11 is placed in the containment space 15a of the container 15. An opening 15d is formed on the substrate B side of the containment space 15a. The opening 15d of the container 15 is covered with an electrolyte membrane 13. Specifically, the periphery of the electrolyte membrane 13 is sandwiched between the container 15 and the frame 17. This allows the plating solution L in the containment space 15a to be sealed with the electrolyte membrane 13.

[0024] As shown in Figures 1 and 3, the linear actuator 70 raises and lowers the housing 15 so that the electrolyte membrane 13 and the masking material 60 can move in and out of contact. In this embodiment, the mounting base 40 is fixed, and the housing 15 is raised and lowered by the linear actuator 70. The linear actuator 70 is an electrically operated actuator that converts the rotational motion of a motor into linear motion using a ball screw or the like (not shown). However, a hydraulic or pneumatic actuator may be used instead of an electrically operated actuator.

[0025] The housing 15 has a supply channel 15b for supplying the plating solution L to the housing space 15a. Furthermore, the housing 15 has a discharge channel 15c for discharging the plating solution L from the housing space 15a. The supply channel 15b and the discharge channel 15c are holes that communicate with the housing space 15a. The supply channel 15b and the discharge channel 15c are formed on either side of the housing space 15a. The supply channel 15b is fluidically connected to the liquid supply pipe 51. The discharge channel 15c is fluidically connected to the liquid discharge pipe 52.

[0026] The film deposition apparatus 1 further comprises a liquid tank 90, a liquid supply pipe 51, a liquid discharge pipe 52, and a pump 80. As shown in Figure 1, the liquid tank 90 contains the plating solution L. The liquid supply pipe 51 connects the liquid tank 90 to the housing 15. The pump 80 is provided on the liquid supply pipe 51. The pump 80 supplies the plating solution L from the liquid tank 90 to the housing 15. The liquid discharge pipe 52 connects the liquid tank 90 to the housing 15. The liquid discharge pipe 52 is provided on the pressure regulating valve 54. The pressure regulating valve 54 adjusts the pressure (liquid pressure) of the plating solution L in the housing space 15a to a predetermined pressure.

[0027] In this embodiment, the plating solution L is drawn from the liquid tank 90 into the liquid supply pipe 51 by driving the pump 80. The drawn-in plating solution L is then pumped from the supply channel 15b to the containment space 15a. The plating solution L in the containment space 15a is returned to the liquid tank 90 via the discharge channel 15c. In this way, the plating solution L circulates within the film deposition apparatus 1.

[0028] Furthermore, by continuously driving the pump 80, the liquid pressure of the plating solution L in the containment space 15a can be maintained at a predetermined pressure by the pressure regulating valve 54. The pump 80 presses the masking material 60 through the porous plate 30 with the electrolyte membrane 13 on which the liquid pressure of the plating solution L acts. However, the pressing mechanism is not particularly limited as long as the electrolyte membrane 13 can press the masking material 60. Instead of the pump 80, an injection mechanism consisting of a piston and cylinder that injects the plating solution L may also be used.

[0029] The mounting base 40 is formed, for example, from a conductive material (e.g., metal). The mounting base 40 has a recess 41. The recess 41 is a portion recessed from the opposite surface of the mounting base 40 in order to accommodate the base material B.

[0030] The masking material 60 comprises a frame 61 and a screen mask 62. The frame 61 supports the peripheral edge 62a of the screen mask 62 on the electrolyte membrane 13 side relative to the frame 61. Specifically, the peripheral edge of the screen mask 62 is fixed to the frame 61. In this embodiment, the screen mask 62 has a rectangular outer shape. Therefore, the frame 61 has a rectangular frame-like shape. The material of the frame 61 is not particularly limited as long as it can maintain the shape of the masking material 60. For example, the material of the frame 61 can be a metal material such as stainless steel, or a resin material such as thermoplastic resin. The frame 61 is formed, for example, by punching out a metal plate and has a thickness of about 1 mm to 3 mm.

[0031] The screen mask 62 has through-portions 68 formed according to a predetermined pattern P of the metal film F. The screen mask 62 comprises a mesh portion 64 and a mask portion 65. The screen mask 62 is a mask with a flexibility of approximately 50 μm to 400 μm. The screen mask 62 is supported on the surface of the frame 61 that is on the substrate B side.

[0032] The periphery of the mesh portion 64 is fixed to the frame 61. The mesh portion 64 is stretched with a predetermined tension so as to cover the opening of the frame 61. Multiple openings are formed in a grid pattern in the mesh portion 64. Specifically, as shown in Figure 4, the mesh portion 64 consists of a mesh-like portion (mesh) in which multiple oriented wires are woven together so as to intersect. Multiple wires are arranged with gaps between them, and multiple intersecting wires are also arranged with gaps between them. As a result, multiple openings are formed in a grid pattern in the mesh portion 64. The material of the wires is not particularly limited as long as it has corrosion resistance to the plating solution L. For example, resin materials such as polyester resin can be used as the material for the wires. In addition, the mesh portion 64 may be made of resin materials such as acrylic resin, vinyl acetate resin, polyvinyl chloride resin, polypropylene resin, polyethylene resin, polystyrene resin, polycarbonate resin, polyimide resin, or urethane resin, as long as it can form wires.

[0033] The mask portion 65 is held by a sheet-like mesh portion 64. The mask portion 65 has through portions 68 formed according to a predetermined pattern P. The mask portion 65 is the part that adheres to the substrate B during film formation due to pressure from the electrolyte membrane 13. The material is not limited as long as it can adhere to the substrate B, but in this embodiment, the mask portion 65 is made of a rubber material. For example, the material of the mask portion 65 can be a rubber material such as silicone rubber (PMDS) or ethylene propylene diene rubber (EPDM). The hardness of the rubber material is preferably HS100 or less on the Shore A hardness scale, and more preferably HS50 or less.

[0034] The mask portion 65 is made of an elastic material that undergoes compressive elastic deformation upon pressure from the electrolyte membrane 13. To ensure adhesion with the substrate B, the amount of deformation of the mask portion 65 in the thickness direction (pressure direction) due to pressure from the electrolyte membrane 13 may be in the range of 5 to 20% of the thickness of the mask portion before deformation. A screen mask 62 having a predetermined pattern P can be manufactured using general silkscreen manufacturing techniques using emulsions. Therefore, a detailed explanation of the manufacturing method of the screen mask 62 is omitted.

[0035] As shown in Figure 4, the mask portion 65 comprises a first portion 65a facing the electrolyte membrane 13 and a second portion 65b facing the substrate B. The mesh portion 64 is positioned between the first portion 65a and the second portion 65b and is the portion that holds the first portion 65a and the second portion 65b. That is, the mesh portion 64 is sandwiched between the first portion 65a and the second portion 65b, and the first portion 65a and the second portion 65b are connected through the opening 64c of the mesh portion 64. The force acting on the mesh portion 64 due to the liquid pressure of the plating solution L during film formation can be uniformly distributed to the second portion 65b. As a result, the deformation of the second portion 65b can be made uniform, and the sealing performance between the mask portion 65 and the substrate B can be stably ensured.

[0036] In this embodiment, a porous plate 30 is placed between the electrolyte membrane 13 and the mask portion 65. The porous plate 30 is a plate with multiple pores through which the plating solution L passes. The porous plate 30 is not particularly limited as long as it is electrically insulated from the anode 11, but in this embodiment, the material of the porous plate 30 is preferably a material with a high Young's modulus, such as polyetheretherketone (PEEK), acrylic resin, resin materials such as polytetrafluoroethylene (PTFE), glass such as chemically strengthened glass, and ceramics such as alumina. The porous plate 30 may also be a metal plate body with an insulating treatment applied to its surface. Among these, the material of the porous plate 30 is preferably chemically strengthened glass. The Young's modulus of chemically strengthened glass is approximately 76100 MPa.

[0037] As described above, the porous plate 30 has multiple pores through which the plating solution L passes. In addition, during film formation, electrolysis is formed in the multiple pores from the anode 11 toward the substrate B. In this embodiment, when the porous plate 30 is made of chemically strengthened glass, the pores are through holes formed along the thickness direction of the porous plate 30. Such pores can be formed by laser processing or the like. In this embodiment, the diameter of the pores is preferably 50 to 100 μm, and the pitch of the pores is preferably 50 to 100 μm. By satisfying these ranges, the rigidity of the porous plate 30 can be ensured, and the plating solution L can be supplied from the porous plate 30 through the pores to the through-holes 68, thereby forming a homogeneous wiring pattern.

[0038] The porous plate 30 is positioned to cover the through portion 68 of the mask portion 65. As described above, the masking material 60 includes a frame 61 that fixes the periphery of the mesh portion 64. The porous plate 30 is positioned between the electrolyte membrane 13 and the mask portion 65 in a state that is not constrained by the frame 61. In this embodiment, the porous plate 30 is detachably positioned on the surface of the mask portion 65 that faces the electrolyte membrane 13. The porous plate 30 may also be fixed integrally with the mask portion 65.

[0039] Referring to Figures 1 to 4, the film deposition method using the film deposition apparatus 1 will be explained. First, the placement process is performed. In this process, as shown in Figure 1, the substrate B is placed on the mounting table 40. Specifically, the substrate B is placed in the recess 41 of the mounting table 40. In this embodiment, with the substrate B placed in the recess 41, the surface of the substrate B protrudes from the opposing surface of the mounting table 40 (the surface facing the electrolyte membrane 13). This allows the mask portion 65 of the masking material 60 to make uniform contact with the surface of the substrate B.

[0040] Next, the masking material 60 is placed on the mounting base 40. At this time, the masking material 60 is housed so that the surface of the base material B is contained within the internal space of the frame 61 of the masking material 60. Specifically, as shown in Figure 4, the surface of the base material B is covered with the mask portion 65 of the masking material 60. Furthermore, the porous plate 30 is placed so as to cover all the through portions 68 formed in this mask portion 65.

[0041] Next, a pressing process is performed. In this process, the substrate B is pressed by the electrolyte membrane 13 through the porous plate 30 and screen mask 62 by the liquid pressure of the plating solution L in contact with the electrolyte membrane 13. First, the linear actuator 70 is driven. This lowers the container 15 toward the porous plate 30 and masking material 60 from the state shown in Figure 1 to the state shown in Figure 3.

[0042] Next, the pump 80 is driven. This supplies the plating solution L to the containment space 15a of the containment body 15. Since the liquid discharge pipe 52 is equipped with a pressure regulating valve 54, the liquid pressure of the plating solution L in the containment space 15a is maintained at a predetermined pressure. As a result, the liquid pressure of the plating solution L allows the porous plate 30 and the screen mask 62 to be sandwiched between the electrolyte membrane 13 and the substrate B. Furthermore, the liquid pressure of the plating solution L can press the screen mask 62 against the electrolyte membrane 13.

[0043] As shown in Figure 4, this pressure allows the mask portion 65 to adhere tightly to the surface of the substrate B. Since the mask portion 65 is made of rubber material, the liquid pressure of the plating solution L causes the mask portion 65 to compress and elastically deform, improving the adhesion between the mask portion 65 and the substrate B. In this embodiment, a porous plate 30 is placed between the electrolyte membrane 13 and the mask portion 65. Therefore, the liquid pressure of the plating solution L causes the electrolyte membrane 13 to press against the mask portion 65 via the porous plate 30. As a result, the mask portion 65 can be uniformly compressed and elastically deformed.

[0044] Furthermore, since the porous plate 30 is in an unrestrained state, it can follow the deformation of the mask portion 65 when pressed. As a result, even if the porous plate 30 is made of a brittle material such as chemically strengthened glass, the stress acting on the porous plate 30 can be reduced. This improves the durability of the porous plate 30. When the pressure on the electrolyte membrane 13 is sustained, the plating solution L seeps out from the electrolyte membrane 13 which has swollen with the plating solution L. The seeped-out solution (plating solution) La passes through the pores of the porous plate 30, fills the through-holes 68 formed in the screen mask 62, and is pressurized.

[0045] Next, a film formation process is performed. In this process, the pressing state by the electrolyte membrane 13 is maintained, and a metal film F is formed. Specifically, a voltage is applied between the anode 11 and the substrate B. This causes the metal ions contained in the plating solution L to pass through the electrolyte membrane 13. The metal ions that have passed through the electrolyte membrane 13 move to the surface of the substrate B via the seepage solution La and are reduced on the surface of the substrate B. As a result, the metal ions from the plating solution L pass through the through-holes 68, and the metal ions that have passed through are deposited on the surface of the substrate B. In this way, as shown in Figure 2, a metal film F with a predetermined pattern P corresponding to the shape of the through-holes 68 can be formed on the surface of the substrate B. In this way, by uniformly deforming the mask portion 65 made of rubber material, a metal film F with a predetermined pattern P can be formed accurately and uniformly.

[0046] Incidentally, in conventional film deposition apparatuses, the electrolyte membrane can penetrate into the mask portion as the number of deposition cycles increases, deforming the mesh portion to the surface of the substrate. As a result, patterns corresponding to the shape of the mesh portion 64 can be formed on the metal film. However, in this embodiment, since the porous plate 30 is positioned to cover the through-hole portion 68 of the mask portion 65, the electrolyte membrane 13 does not penetrate into the through-hole portion 68. As a result, a homogeneous metal film F can be deposited.

[0047] Subsequently, the linear actuator 70 raises the housing 15, separating the substrate B from the electrolyte membrane 13, and removing the substrate B from the mounting table 40. When manufacturing wiring with a metal film F, it is sufficient to etch the conductive underlayer Bb formed on the surface of the insulating substrate Ba of the substrate B, leaving the portion where the metal film F is formed intact.

[0048] Referring to Figures 5 to 7, the following describes a modified film deposition apparatus. In the film deposition apparatus shown in Figures 1 to 4, the mask portion 65 was held by the mesh portion 64 of the masking material 60, but in the following modified apparatus, the mask portion 65 is held by the porous plate 30. In other words, these modified apparatuses have a different configuration of the masking material 60. Therefore, in the following modified apparatuses, only the different configurations will be described.

[0049] Specifically, as shown in Figures 5(a) and 5(b), in this modified example, the porous plate 30 is fixed to the frame 61. In Figures 5(a) and 5(b), the mask portion 65 is integrally formed on the side of the porous plate 30 facing the substrate B. Unlike the mesh portion, the porous plate 30 is less prone to deformation due to the pressure of the electrolyte membrane 13, thus improving the molding accuracy of the pattern P of the metal film F that is formed.

[0050] Furthermore, in Figure 5(b), a cushion portion 69 corresponding to the shape of the mask portion 65 is formed on the side of the porous plate 30 facing the electrolyte membrane 13. The cushion portion 69 is made of the same material as the mask portion 65, but the material is not particularly limited as long as it is elastically deformable under the pressure from the electrolyte membrane 13. By providing such a cushion portion 69, the area in contact with the porous plate 30 during film formation is reduced, and damage to the electrolyte membrane 13 caused by contact with the porous plate 30 can be suppressed.

[0051] In the modified example shown in Figure 6, a mask portion 65 is integrally formed on the surface of the porous plate 30 facing the base material B. A mesh 32 woven with wire is attached to the periphery 31 of the porous plate 30 so as to surround the porous plate 30. The mesh 32 is rectangular and may be made of the same material and wire as exemplified in the mesh portion described above. The center of the mesh 32 is open to match the size of the rectangular porous plate 30. The inner periphery of the central opening (not shown) of the mesh 32 is fixed to the periphery 31 of the porous plate 30 with an adhesive or the like, overlapping with it. The outer periphery of the mesh 32 is fixed to the surface 61a of the frame 61 with an adhesive or the like.

[0052] In this modified version, the porous plate 30 is constrained to the frame 61 via a flexible mesh 32. Therefore, the mesh 32 bends under pressure from the electrolyte membrane 13, allowing the porous plate 30 to follow the deformation of the mask portion 65. This suppresses damage caused by the deformation of the porous plate 30 and improves its durability. When the pressure from the electrolyte membrane 13 is sustained, the plating solution L seeps out from the electrolyte membrane 13, which has swollen with the plating solution L. The seeped-out solution (plating solution) La passes through the pores of the porous plate 30, fills the through-holes 68 formed in the mask portion 65, and is pressurized. Furthermore, since the mask portion 65 is integrally formed with the porous plate 30, as shown in Figure 7(a), parts of the mask portion 65 other than the thickness direction can be deformed. This improves the molding accuracy of the pattern P of the metal film F.

[0053] Furthermore, as shown in Figure 7(b), a cushion portion 69 corresponding to the shape of the mask portion 65 is further formed on the side of the porous plate 30 facing the electrolyte membrane 13. The cushion portion 69 is made of the same material as the mask portion 65, but the material is not particularly limited as long as it is elastically deformable under the pressure from the electrolyte membrane 13. By providing such a cushion portion 69, the area in contact between the electrolyte membrane 13 and the porous plate 30 during film formation can be reduced, thereby suppressing damage to the electrolyte membrane 13 caused by contact with the porous plate 30. Furthermore, as shown in Figure 7(b), if the mesh 32 is sandwiched between the mask portion 65 and the cushion portion 69, leakage of seepage liquid La from the electrolyte membrane 13 near the frame 61 can be reduced.

[0054] [Examples] Metal films were deposited using the film deposition apparatus shown in Figure 1 and the modified film deposition apparatus shown in Figure 5(a). Mask portions were formed by creating through-holes on both sides of a mesh portion made of LCP resin with a wire diameter of 20 μm and 420 mesh using silicone rubber. This produced a masking material having a mesh portion and a masking portion. The thickness of the mask portion was 30 μm for the first portion and 20 μm for the second portion. Next, a chemically strengthened glass with a thickness of 200 μm, a pore diameter of 100 μm, and a pitch of 100 μm was prepared as a porous plate. A substrate was prepared by forming copper (Cu) by sputtering on a wafer with a square surface of side length 5 mm.

[0055] Subsequently, using a device with a configuration similar to that of the porous plate deposition apparatus, a 2.5 μm thick metal film was deposited on the surface of the substrate by solid-phase electrodeposition (SED) under vacuum conditions. The deposition conditions were as follows: Deposition temperature: 40°C, Plating solution: 1 M copper sulfate and 0.2 M sulfuric acid, Anode: Iridium oxide electrode (insoluble anode), Anode-cathode distance: 5 mm, Pressure: 0.6 MPa, Holding time: 10 minutes, Current: 3.5 ASD

[0056] As a comparative example, film deposition was performed using the deposition apparatus shown in Figure 1, without the porous plate used in the example, under the same conditions as in the example. Defects in the deposition of the example and comparative example films were checked. As a result, the metal film of the example had no defects, while the metal film of the comparative example had a pattern formed according to the shape of the mesh portion of the masking material. From this, it was found that a homogeneous metal film is formed by providing a porous plate, as in the example.

[0057] Although embodiments of the present invention have been described in detail above, the present invention is not limited to the embodiments described above, and various design modifications can be made without departing from the spirit of the invention as described in the claims. [Explanation of Symbols]

[0058] 1: Film deposition apparatus, 11: Anode, 13: Electrolyte membrane, 30: Porous plate, 60: Masking material, 61: Frame, 62: Screen mask, 64: Mesh part, 65: Mask part, 65a: First part, 65b: Second part, 65c: Opposing surface, 68: Through part, B: Substrate, F: Metal film, L: Plating solution

Claims

1. A metal film deposition apparatus for depositing a metal film with a predetermined pattern onto the surface of a substrate by electroplating, The aforementioned film deposition apparatus is A container having an opening formed at a position opposite to the substrate, containing a plating solution, and the opening covered with an electrolyte membrane, A pressing mechanism that presses the substrate with the electrolyte membrane by the liquid pressure of the plating solution contained in the container, Inside the container, an anode is positioned opposite the electrolyte membrane, The system comprises a masking material disposed between the electrolyte membrane and the substrate, having a predetermined pattern of penetrating portions formed thereon, The masking material has the through portion formed therein and a mask portion made of rubber material, A metal film deposition apparatus comprising a porous plate having a plurality of pores through which the plating solution passes, positioned between the electrolyte membrane and the mask portion so as to cover the through-hole portion.

2. The mask portion comprises a first portion facing the electrolyte membrane and a second portion facing the substrate. The metal film forming apparatus according to claim 1, wherein the masking material has a mesh portion woven with wire, the mesh portion is positioned between the first portion and the second portion and holds the first portion and the second portion.

3. The masking material includes a frame that secures the periphery of the mesh portion. The metal film deposition apparatus according to claim 2, wherein the porous plate is disposed between the electrolyte membrane and the mask portion in a state that is not constrained by the frame.

4. The mask portion is fixed to the surface of the porous plate that faces the substrate, A mesh woven from wire is attached to the periphery of the porous plate so as to surround it. The metal film deposition apparatus according to claim 1, wherein the outer edge of the mesh is fixed to the frame.

5. The apparatus for forming a metal film according to claim 1, wherein the porous plate is made of chemically strengthened glass, and the pores are through holes formed along the thickness direction of the porous plate.

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