Metal coating deposition method

Abstract

To provide a deposition method for a metallic film, by which a screen mask is stably peeled from a substrate after the deposition of the metallic film.SOLUTION: A deposition method includes: depositing a metallic film F with a prescribed pattern P on a substrate B; releasing a press on the substrate B by a polymer electrolyte 13; and deforming an edge part 62a of a screen mask 62 contacting the substrate B so that a gap S is formed between the substrate B and the edge part 62a of the screen mask 62. The screen mask 62 with the deformed edge part 62a is peeled from the substrate B by relatively separating a container 15 from a placement table 40.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a film forming method for forming a metal film in a predetermined pattern on the surface of a substrate. [Background technology]

[0002] Conventionally, metal coatings have been formed by depositing metal on the surface of a substrate by electrolytic plating (see, for example, Patent Document 1). In Patent Document 1, a film formation apparatus includes a container that contains a plating solution. The container has an opening that is sealed with an electrolyte membrane. The film formation apparatus further includes a pressing mechanism that presses the electrolyte membrane against the substrate using the hydraulic pressure of the plating solution.

[0003] Here, if a metallic underlayer with a predetermined pattern is formed on the surface of the substrate, a voltage is applied between the anode and the substrate while the substrate is pressed by the hydraulic pressure of the electrolyte membrane. This allows a metallic coating with the predetermined pattern to be formed on the underlayer. However, if the substrate does not have a predetermined pattern underlayer, it is also possible to use a masking material such as that shown in Patent Document 2. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-125087 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-108586 Summary of the Invention [Problem to be solved by the invention]

[0005] When a metal coating is formed using a screen mask as a masking material, the screen mask is sandwiched between a substrate and an electrolyte membrane. In this state, to ensure close contact between the substrate and the screen mask, the screen mask is pressed by the electrolyte membrane, to which the hydraulic pressure of the plating solution acts, while the metal coating is formed on the surface of the substrate. After film formation, the perforations in the screen mask are filled with plating solution that has seeped out of the electrolyte membrane, and the screen mask is in close contact with the substrate. However, if an attempt is made to separate the substrate from the screen mask in this state, the substrate may move together with the screen mask, potentially deforming the screen mask.

[0006] The present invention has been made in view of the above points, and has as its object to provide a method for forming a metal film that enables the screen mask to be stably separated from the substrate after the metal film has been formed. [Means for solving the problem]

[0007] In view of the above-mentioned problems, a metal film forming method according to the present invention is a film forming method for forming a metal film of a predetermined pattern on a surface of a substrate through a screen mask having perforations formed in the predetermined pattern, the method comprising the steps of: placing the substrate on a mounting table; bringing a container in which a plating solution is sealed with an electrolyte membrane and the mounting table relatively close to each other, thereby bringing the screen mask attached to the container at a position facing the electrolyte membrane into contact with the substrate; pressing the substrate with the electrolyte membrane through the screen mask by applying hydraulic pressure of the plating solution contained in the container; a film-forming step of applying a voltage between the substrate and an anode in contact with the plating solution while the substrate is pressed against the electrolyte membrane, thereby causing metal ions contained in the plating solution to pass through the electrolyte membrane and forming a metal film derived from the metal ions on the substrate in the predetermined pattern; a deformation step of releasing the pressure on the substrate from the electrolyte membrane and deforming the edge of the screen mask in contact with the substrate so as to form a gap between the substrate and the edge of the screen mask; and a separation step of separating the substrate from the screen mask with the edge deformed by relatively separating the container and the mounting stand. [Effects of the Invention]

[0008] According to the present invention, with the screen mask in contact with the substrate, the electrolyte membrane presses the substrate through the screen mask by the hydraulic pressure of the plating solution in contact with the electrolyte membrane. When a metal film is formed on the surface of the substrate in this pressed state, the plating solution seeps out from the electrolyte membrane. The exuded plating solution fills the perforated portions of the screen mask.

[0009] After the metal film is formed, the pressure applied by the electrolyte membrane to the substrate is released. According to the present invention, the edge of the screen mask in contact with the substrate is deformed so that a gap is formed between the substrate and the edge of the screen mask when the pressure is released. As a result, when the container and the mounting table are separated from each other, air enters through the gap formed between the substrate and the edge of the screen mask, and the screen mask can be stably separated from the substrate. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1(a) is a schematic cross-sectional view showing an example of a metal film forming apparatus according to an embodiment of the present invention, FIG. 1(b) is a schematic perspective view of a screen mask, and FIG. 1(c) is a partially enlarged cross-sectional view taken along line AA of FIG. [Figure 2] 1 is a flow diagram illustrating an example of a method for forming a metal film using a film forming apparatus according to an embodiment of the present invention. [Figure 3] 3A is a schematic cross-sectional view for explaining the film formation process shown in FIG. 2, FIG. 3B is a schematic perspective view for explaining the deformation process shown in FIG. 2, and FIG. 3C is an enlarged view of part c shown in FIG. 2B. [Figure 4] 3A is a schematic cross-sectional view illustrating an example of an auxiliary step shown in FIG. 2, FIG. 3B is a schematic cross-sectional view illustrating another auxiliary step shown in FIG. 2, and FIG. 3C is a view illustrating yet another auxiliary step shown in FIG. 2. [Figure 5] 3(a) is a schematic cross-sectional view illustrating an example of the separation step shown in FIG. 2, and FIG. 3(b) is a view illustrating another separation step shown in FIG. 2. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0011] First, a film formation apparatus 1 used in a method for forming a metal film according to an embodiment of the present invention will be described. Fig. 1 is a schematic cross-sectional view showing an example of a film formation apparatus for forming a metal film according to an embodiment of the present invention. Fig. 2 is a flow diagram illustrating an example of a method for forming a metal film using the film formation apparatus according to an embodiment, and in order to explain the configuration of the film formation apparatus, the configurations of the apparatus exemplified in Figs. 3 to 5 will also be described in detail before explaining Fig. 2.

[0012] 1, the film formation apparatus 1 is a film formation apparatus that forms a metal coating F of a predetermined pattern P on a substrate B by electrolytic plating with a mask structure 60 sandwiched between an electrolyte membrane 13 and the substrate B. Specifically, the film formation apparatus 1 includes an anode 11, an electrolyte membrane 13, and a power supply 14 that applies a voltage between the anode 11 and the substrate B.

[0013] The film forming apparatus 1 includes a container 15 that contains an anode 11 and a plating solution L, a mounting table 40 on which a substrate B is placed, and a mask structure 60 that is integrally attached to the container 15. Of the mask structure 60, a screen mask 62 (described later) is attached to the container 15 at a position facing the electrolyte membrane 13.

[0014] The film forming apparatus 1 includes a linear actuator 70 that raises and lowers the housing 15. The linear actuator 70 has a rod 72 that moves linearly relative to a main body 71, and the housing 15 is fixed to the tip of the rod 72. In this embodiment, for convenience of explanation, the electrolyte membrane 13 is disposed below the anode 11, and the mask structure 60 and the substrate B are disposed further below that. However, the positional relationship between the electrolyte membrane 13 and the substrate B is not particularly limited as long as the metal coating F can be formed on the surface of the substrate B.

[0015] The mounting table 40 is formed of, for example, a conductive material (e.g., metal). The mounting table 40 has a recess 41 formed therein for accommodating the substrate B. A holding device 38 for holding the substrate B on the mounting table 40 is disposed on the mounting table 40. The holding device 38 includes a pressing device 37 for pressing the side surface of the substrate B and releasing the pressing force, and a pad 36 attached to the tip (rod tip) of the pressing device 37. The pressing device 37 may be a linear actuator having an electric screw mechanism, or may be a pneumatic cylinder. The holding device 38 may also be one that sucks the substrate B from the backside.

[0016] Substrate B functions as a cathode. Substrate B is a plate-shaped substrate. In this embodiment, substrate B is a rectangular substrate. Of the surfaces of substrate B, the opposing surface Ba facing the electrolyte membrane 13 (screen mask 62) is a film formation surface that functions as a cathode. The material of substrate B is not particularly limited as long as it functions as a cathode (i.e., a surface having electrical conductivity). Substrate B may be made of a metal material such as aluminum or copper. When forming a wiring pattern from a metal coating F, substrate B is used as a substrate in which a base layer such as copper is formed on the surface of an insulating substrate such as resin. In this case, after forming the metal coating F, the base layer other than the portion where the metal coating F is formed is removed by etching or the like. This allows a wiring pattern made of metal coating F to be formed on the surface of the insulating substrate.

[0017] The anode 11 is, for example, a non-porous anode made of the same metal as the metal of the metal coating. The anode 11 has a block or flat plate shape. The anode 11 may be porous, mesh, or a cage containing multiple balls. Examples of materials for the anode 11 include copper. The anode 11 dissolves when a voltage is applied from the power source 14. However, when forming a film using only metal ions of the plating solution L, the anode 11 is an anode that is insoluble in the plating solution L. The anode 11 is electrically connected to the positive electrode of the power source 14. The negative electrode of the power source 14 is electrically connected to the substrate B via the mounting table 40.

[0018] The plating solution L is a solution containing the metal of the metal coating to be formed in an ionic state. Examples of such metals include copper, nickel, gold, and silver. The plating solution L is a solution in which these metals are dissolved (ionized) in an acid such as nitric acid, phosphoric acid, succinic acid, sulfuric acid, sulfamic acid, or pyrophosphoric acid. Examples of the solvent for the solution include water and alcohol. For example, when the metal is copper, the plating solution L can be an aqueous solution containing copper sulfate, copper pyrophosphate, or the like.

[0019] The electrolyte membrane 13 is a membrane that can be impregnated (contain) metal ions together with the plating solution L by contacting it with the plating solution L. The electrolyte membrane 13 is a flexible membrane. The material of the electrolyte membrane 13 is not particularly limited as long as it allows the metal ions of the plating solution L to migrate to the substrate B side when a voltage is applied from the power source 14. Examples of materials for the electrolyte membrane 13 include resins with ion exchange properties, such as fluororesins such as Nafion (registered trademark) manufactured by DuPont. The thickness of the electrolyte membrane 13 is preferably in the range of 5 μm to 200 μm. More preferably, the thickness is in the range of 20 μm to 60 μm.

[0020] The container 15 is made of a material that is insoluble in the plating solution L. A container space 15a that contains the plating solution L is formed in the container 15. The anode 11 is disposed in the container space 15a of the container 15. An opening 15d is formed on the side of the container space 15a facing the substrate B. 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 61. This allows the plating solution L in the container space 15a to be sealed by the electrolyte membrane 13.

[0021] As shown in FIGS. 1(a) and 3(a), the linear actuator 70 moves the rod 72 linearly to raise and lower the housing 15 so that the electrolyte membrane 13 and the mask structure 60 can be moved toward and away from each other. In this embodiment, the mounting table 40 is fixed, and the housing 15 is raised and lowered by the linear actuator 70. The linear actuator 70 is an electric actuator that converts the rotational motion of a motor into linear motion using a ball screw or the like (not shown). However, instead of the electric actuator, a hydraulic or pneumatic actuator may be used.

[0022] The container 15 has a supply port 15b that supplies the plating solution L to the container space 15a. The container 15 has a discharge port 15c that discharges the plating solution L from the container space 15a. The supply port 15b and the discharge port 15c are holes that communicate with the container space 15a. The supply port 15b and the discharge port 15c are formed on either side of the container space 15a. The supply port 15b is connected to a supply pipe 51. The discharge port 15c is fluidly connected to a discharge pipe 52.

[0023] The film forming apparatus 1 further includes a tank 90, a supply pipe 51, a discharge pipe 52, and a pump 80. As shown in FIG. 1 , the tank 90 contains a plating solution L. The supply pipe 51 connects the tank 90 to the accommodation body 15. The supply pipe 51 is provided with a pump 80. The pump 80 supplies the plating solution L from the tank 90 to the accommodation body 15. The discharge pipe 52 connects the tank 90 to the accommodation body 15. The discharge pipe 52 is provided with a pressure adjustment valve 54. The pressure adjustment valve 54 adjusts the pressure (liquid pressure) of the plating solution L in the accommodation space 15a to a predetermined pressure.

[0024] In this embodiment, the plating solution L is sucked from the tank 90 into the supply pipe 51 by driving the pump 80. The sucked plating solution L is pressure-fed from the supply port 15b to the accommodation space 15a. The plating solution L in the accommodation space 15a is returned to the tank 90 via the discharge port 15c. In this manner, the plating solution L circulates within the film forming apparatus 1.

[0025] Furthermore, by continuing to drive the pump 80, the liquid pressure of the plating solution L in the accommodation space 15a can be maintained at a predetermined pressure by the pressure regulating valve 54. The pump 80 presses the electrolyte membrane 13, to which the liquid pressure of the plating solution L acts, against the screen mask 62 of the mask structure 60. However, the pressing mechanism is not particularly limited as long as it can press the mask structure 60 with the electrolyte membrane 13. Instead of the pump 80, an injection mechanism consisting of a piston and a cylinder that injects the plating solution L may be used.

[0026] As shown in FIG. 1(a), the mask structure 60 is attached to the housing 15 at a position facing the electrolyte membrane 13 on the side facing the mounting table 40. As shown in FIG. 1(b), the mask structure 60 includes a frame 61 and a screen mask 62. The screen mask 62 has through-holes 68 formed therein according to a predetermined pattern P of the metal coating F. The screen mask 62 includes a mesh portion 64 and a mask portion 65. The screen mask 62 is a mask having flexibility of approximately 50 μm to 400 μm. The screen mask 62 is supported by the frame 61 at a surface of the frame 61 that faces the substrate B (facing surface).

[0027] The mesh portion 64 is fixed to the frame 61. As shown in FIG. 1(c), the mesh portion 64 is stretched with a predetermined tension so as to cover the opening of the frame 61. A plurality of openings 64c are formed in the mesh portion 64 in a lattice pattern. The mesh portion 64 is formed by weaving a plurality of oriented wires 64a, 64b so that they intersect with each other. The plurality of wires 64a are arranged at intervals, and the plurality of intersecting wires 64b, 64b are arranged at intervals. As a result, a plurality of openings 64c are formed in the mesh portion 64 in a lattice pattern. The material of the wires 64a, 64b is not particularly limited as long as it is corrosion-resistant to the plating solution L. Examples of materials for the wires 64a, 64b include metal materials such as stainless steel and resin materials such as polyester.

[0028] The mask portion 65 is fixed to the mesh portion 64 on one of the two surfaces of the mesh portion 64 facing the substrate B. The mask portion 65 has through-holes 68 formed therein according to a predetermined pattern P. The mask portion 65 is a portion that adheres closely to the substrate B due to pressure from the electrolyte membrane 13 during film formation. The material of the mask portion 65 is not particularly limited as long as it can adhere closely to the substrate B. It is preferable that the mask portion 65 undergoes compressive elastic deformation due to pressure from the electrolyte membrane 13. Examples of materials for the mask portion 65 include resin materials such as acrylic resin, vinyl acetate resin, polyvinyl resin, polyimide resin, and polyester resin. The screen mask 62 having the predetermined pattern P can be manufactured using a general silkscreen manufacturing technique using emulsion. Therefore, a detailed description of the manufacturing method for the screen mask 62 will be omitted.

[0029] The frame 61 supports the peripheral edge 62a of the screen mask 62 on the surface facing the substrate B (mounting table 40). The frame 61 fits into the opening 15d of the housing 15. This allows the screen mask 62 to be attached to the housing 15. 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 mask structure 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 a metal plate and has a thickness of about 1 mm to 3 mm.

[0030] In this embodiment, there is provided a push-up member 32 that pushes up an edge 62a (specifically, an edge of a mask portion 65) of a screen mask 62 that is in contact with a substrate B, thereby deforming the edge 62a. The push-up member 32 includes a rack portion 32a that meshes with a pinion 31 that is rotated by a motor 34, and an extension portion 32b that is connected to the rack portion 32a and extends to a position where it contacts the edge 62a of the screen mask 62. The tip of the extension portion 32b contacts the edge 62a along the edge (periphery) 62a of the screen mask 62.

[0031] 3(b) and 3(c), when the motor 34 is rotated in the forward direction, the pinion 31 rotates forward, the rack portion 32a moves in a direction away from the mounting table 40, and the edge of the mask portion 65 is compressed and deformed. As a result, the push-up member 32 pushes up the edge 62a of the screen mask 62. At this time, it is preferable to position the tip of the push-up member 32 in a position where the edge of the mask portion 65 and the mesh portion 64 fixed to this edge are deformed toward the accommodation space 15a. On the other hand, when the motor 34 is rotated in the reverse direction, as shown in FIG. 3(a), the pinion 31 rotates in the reverse direction, and the rack portion 32a moves in a direction away from the mounting table 40, returning the edge 62a of the screen mask 62 pushed up by the push-up member 32 to its original state.

[0032] In addition, as shown in FIG. 4( a), the film forming apparatus 1 may also include a vibration device 91 that vibrates the mounting table 40. The vibration device 91 is preferably a device that vibrates in a direction normal to the surface of the substrate B (thickness direction of the substrate B). Furthermore, as shown in FIG. 4( b), the film forming apparatus 1 may also include a rotation device 92 that rotates the mounting table 40. The rotation device 92 is, for example, a motor. By driving the motor, the mounting table 40 can be rotated, and the substrate B can be rotated around a rotation axis CL that is normal to the substrate B. Furthermore, as shown in FIG. 4( c), the film forming apparatus 1 may also include a cooling device 93 that cools the mounting table 40. The cooling device 93 includes, for example, a Peltier element. By passing a current through the Peltier element, the mounting table 40 absorbs heat, and the substrate B can be cooled together with the mounting table 40.

[0033] 5(b), a tilting mechanism 39A may be provided to tilt the mounting table 40. The tilting mechanism 39A is made up of a plurality (two) of actuators 39b attached to the bottom surface of the mounting table 40, with rods 39a at the tips of which move linearly in the vertical direction. This drives the actuators 39b to tilt the substrate B relative to the screen mask 62, thereby separating the screen mask 62 and the substrate B.

[0034] 2 will be described below with reference to the above-mentioned Figures 3 to 5. In this film formation method, a metal film F having a predetermined pattern P is formed on the surface of a substrate B through a screen mask 62 having through-holes 68 having the predetermined pattern P formed thereon.

[0035] First, in a placing step S1, the substrate B is placed on the placing table 40. At this time, the substrate B may be heated to increase the film formation rate. Next, in a contacting step S2, the container 15 in which the plating solution L is sealed with the electrolyte membrane 13 and the placing table 40 are brought relatively close to each other. Specifically, the linear actuator 70 is driven to lower the container 15. As a result, the screen mask 62 attached to the container 15 at a position opposite the electrolyte membrane 13 is brought into contact with the substrate B.

[0036] Next, a pressing step S3 is performed. In this step, the electrolyte membrane 13 presses the substrate B through the screen mask 62 by the hydraulic pressure of the plating solution L in contact with the electrolyte membrane 13. Specifically, the pump 80 is driven. This supplies the plating solution L to the accommodation space 15a of the accommodation body 15. Because the pressure adjustment valve 54 is provided in the discharge pipe 52, the hydraulic pressure of the plating solution L in the accommodation space 15a is maintained at a predetermined pressure. As a result, the hydraulic pressure of the plating solution L accommodated in the accommodation body 15 acts to deform the electrolyte membrane 13 toward the internal space of the frame 61, thereby sandwiching the screen mask 62 between the electrolyte membrane 13 and the substrate B. The electrolyte membrane 13 presses the substrate B through the screen mask 62. At this time, if the mask portion 65 is made of an elastic rubber or resin material, the mask portion 65 is compressed and elastically deformed by the hydraulic pressure of the plating solution L, improving the adhesion between the mask portion 65 and the substrate B.

[0037] Next, the film-forming step S4 is performed. In this step, the pressing state by the electrolyte membrane 13 in the pressing step S3 is maintained, and a metal film F is formed. Specifically, a voltage is applied between the anode 11 and the substrate B. This causes 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 migrate to the surface of the substrate B via the oozing liquid La, where they are reduced. The oozing liquid La filled in the through-portion 68 is sealed within the through-portion 68 by the electrolyte membrane 13, so that a metal film F having a predetermined pattern can be formed on the surface of the substrate B (see FIG. 3(a)). The metal film F is a film derived from metal ions. The oozing liquid La is uniformly pressurized by the pressure of the electrolyte membrane 13, so that a homogeneous metal film F can be formed. The plating solution L and the substrate B may be heated during film formation.

[0038] Next, a deformation step S5 is performed. In this step, first, the pressure applied to the substrate B by the electrolyte membrane 13 is released. Specifically, the operation of the pump 80 is stopped. The plating solution L in the accommodation space 15a of the accommodation body 15 is replaced with air at atmospheric pressure (atmosphere). Here, for example, compressed air may be sent to the accommodation space 15a by an air pump (not shown). Alternatively, a valve (not shown) of a drainage pipe (not shown) that connects the accommodation space 15a to the atmosphere may be opened.

[0039] 3(b) and 3(c), the edge 62a of the screen mask 62 in contact with the substrate B is deformed so that a gap S is formed between the substrate B and the edge 62a of the screen mask 62. Specifically, the motor 34 is rotated in the forward direction to move the rack portion 32a in a direction away from the mounting table 40, thereby compressively deforming the edge of the mask portion 65. This causes the push-up member 32 to push up the edge 62a of the screen mask 62. Note that in this embodiment, the entire periphery of the edge 62a of the screen mask 62 is deformed, but the edge 62a may also be partially deformed.

[0040] Next, auxiliary step S6 is performed. This step is performed after deformation step S5 and before separation step S7, and is intended to support the separation of screen mask 62 and substrate B in separation step S7, which will be described later. Therefore, if separation can be easily performed after deformation step S5, auxiliary step S6 may be omitted. Auxiliary step S6 is performed using at least one of the configurations shown in FIGS. 4(a) to 4(c) above, but several of these configurations may also be used in combination. In auxiliary step S6 and separation step S7, substrate B is maintained in a held (restrained) state on mounting table 40 by holding device 38.

[0041] As shown in FIG. 4(a), the auxiliary step S6 is a vibration step. In the vibration step, the substrate B is vibrated by a vibration device 91 relative to the screen mask 62 in a state in which the edge portion 62a is deformed. Specifically, the vibration device 91 vibrates the substrate B together with the mounting table 40 in a direction along the normal to the surface of the substrate B (the thickness direction of the substrate B). Since the substrate B is restrained by the mounting table 40, air easily enters between the substrate B and the screen mask 62 through the gap S. Note that in the vibration step, either the screen mask 62 in a state in which the edge portion 62a is deformed or the substrate B may be vibrated.

[0042] As shown in FIG. 4(b), auxiliary step S6 is a rotation step. In this step, by driving rotation device 92, substrate B is rotated relative to screen mask 62 with edge portion 62a deformed, around rotation axis CL, which is the normal to the surface of substrate B. As a result, edge portion 62a of screen mask 62 is deformed, and this portion serves as the starting point for peeling, allowing shear force to be applied to the interface between screen mask 62 and substrate B. Note that in this step, screen mask 62 may be rotated relative to substrate B together with housing body 15.

[0043] As shown in FIG. 4( c), auxiliary step S6 is a cooling step. In this step, the substrate B is cooled by a cooling device 93. By utilizing the difference in thermal contraction between the substrate B and the screen mask 62, a shear force can be applied to the interface between the screen mask 62 and the substrate B, with the deformed edge 62a of the screen mask 62 serving as the starting point for peeling. This makes it possible to more stably perform the separation step S7, which will be described later. In this embodiment, the cooling device 93 cools the substrate B together with the mounting table 40. However, the screen mask 62 and the substrate B may also be cooled by, for example, flowing a plating solution L at a temperature lower than that during film formation into the container 15. For example, if the metal coating F and the base layer of the substrate B are made of copper, cooling the substrate B from 70° C. to 20° C. during film formation can cause the substrate B to shrink by several hundred micrometers (e.g., 800 μm).

[0044] Next, a separation step S7 is performed. In this step, the housing body 15 is moved away from the mounting table 40 to separate the screen mask 62, with the edge portion 62a deformed, from the substrate B. Specifically, as shown in FIG. 5(a), the housing body 15 may be raised by driving a linear actuator 70. Alternatively, as shown in FIG. 5(b), the screen mask 62 and the substrate B may be separated by tilting the substrate B relative to the screen mask 62 using a tilting mechanism 39A. By tilting the substrate B, air can easily enter between the substrate B and the screen mask 62 through the gap S, allowing the screen mask 62 to be stably separated from the substrate B.

[0045] As described above, according to this embodiment, in the deformation step S5, the edge portion 62a of the screen mask 62 in contact with the substrate B is deformed so that, with the pressure released, a gap S is formed between the substrate B and the edge portion 62a of the screen mask 62. As a result, when the housing body 15 and the mounting table 40 are relatively separated from each other, air enters through the gap S between the substrate B and the edge portion 62a of the screen mask 62, and the screen mask 62 can be stably separated from the substrate B.

[0046] 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 design modifications can be made without departing from the spirit of the present invention as set forth in the claims. [Explanation of symbols]

[0047] 1: film forming device, 13: electrolyte membrane, 15: container, 40: mounting table, 62: screen mask, 68: penetration portion, B: substrate, F: metal film, P: predetermined pattern

Claims

1. 1. A film formation method for forming a metal film having a predetermined pattern on a surface of a substrate through a screen mask having through-holes in the predetermined pattern, the method comprising: a placing step of placing the substrate on a placing table; a contacting step of bringing a container in which a plating solution is sealed with an electrolyte membrane and the stage relatively close to each other, thereby bringing the screen mask attached to the container at a position facing the electrolyte membrane into contact with the substrate; a pressing step of pressing the substrate with the electrolyte membrane via the screen mask by applying a liquid pressure of the plating solution contained in the container; a film-forming step of applying a voltage between the substrate and an anode in contact with the plating solution while the substrate is pressed by the electrolyte membrane, thereby causing metal ions contained in the plating solution to pass through the electrolyte membrane and forming a metal coating derived from the metal ions on the substrate in the predetermined pattern; a deformation step of releasing the pressure applied to the substrate by the electrolyte membrane and deforming the edge portion of the screen mask that is in contact with the substrate so that a gap is formed between the substrate and the edge portion of the screen mask; a separating step of separating the screen mask with the edge portion deformed from the substrate by relatively separating the container and the mounting table, A method for forming a metal film, comprising, after the deformation step and before the separation step, a rotation step of rotating either the screen mask in a state in which the edge portion is deformed or the substrate around a rotation axis that is a normal to the surface of the substrate.

2. 1. A film formation method for forming a metal film having a predetermined pattern on a surface of a substrate through a screen mask having through-holes in the predetermined pattern, the method comprising: a placing step of placing the substrate on a placing table; a contacting step of bringing a container in which a plating solution is sealed with an electrolyte membrane and the stage relatively close to each other, thereby bringing the screen mask attached to the container at a position facing the electrolyte membrane into contact with the substrate; a pressing step of pressing the substrate with the electrolyte membrane via the screen mask by applying a liquid pressure of the plating solution contained in the container; a film-forming step of applying a voltage between the substrate and an anode in contact with the plating solution while the substrate is pressed by the electrolyte membrane, thereby causing metal ions contained in the plating solution to pass through the electrolyte membrane and forming a metal coating derived from the metal ions on the substrate in the predetermined pattern; a deformation step of releasing the pressure applied to the substrate by the electrolyte membrane and deforming the edge portion of the screen mask that is in contact with the substrate so that a gap is formed between the substrate and the edge portion of the screen mask; a separating step of separating the screen mask with the edge portion deformed from the substrate by relatively separating the container and the mounting table, The method for forming a metal film includes a cooling step of cooling the substrate after the deformation step and before the separation step.

3. 3. The method for forming a metal film according to claim 1, wherein the separating step separates the screen mask from the substrate by tilting the substrate relative to the screen mask.

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