Method for forming a metal film and apparatus for forming the same

Abstract

To provide a method for depositing a metal film, capable of depositing the metal film having a predetermined pattern stably in a shorter time, by using a screen mask.SOLUTION: While pressing a base material B with a mask part, a plating solution L exuding from an electrolyte film 13 is filled into a penetrating part 68 by applying voltage for filling between an anode 11 and a metal mesh part 64 with a positive electrode of a power supply 14 connected to the anode 11 and with a negative electrode of the power supply 14 connected to the metal mesh part 64. A metal film F is deposited on the base material B in a predetermined pattern P by applying an electric current between the anode 11 and the base material B, with the base material B pressed by a screen mask 62.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a film forming method and a film forming apparatus for forming a metal film with a predetermined pattern on the surface of a substrate.

Background Art

[0002] Conventionally, metal has been deposited on the surface of a substrate by electrolytic plating to form a metal film (see, for example, Patent Document 1). Patent Document 1 discloses that a film forming apparatus includes a container for storing a plating solution. An opening is formed in the container, and the opening is sealed with an electrolyte membrane. The film forming apparatus further includes a pressing mechanism that presses the substrate with the electrolyte membrane by the hydraulic pressure of the plating solution.

[0003] Here, when a metal underlayer with a predetermined pattern is formed on the surface of the substrate, a voltage is applied between the anode and the substrate while pressing the substrate with the hydraulic pressure of the electrolyte membrane. Thereby, a metal film with a predetermined pattern can be formed on the underlayer. However, when a substrate does not have an underlayer with a predetermined pattern, for example, it is also assumed to use a masking material shown in Patent Document 2.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In this process, when a screen mask is used as a masking material to form a metal film, the screen mask is sandwiched between the substrate and the electrolyte membrane. In this state, to ensure adhesion between the substrate and the screen mask, the screen mask is pressed against the electrolyte membrane by the liquid pressure of the plating solution while the metal film is formed on the surface of the substrate. However, if a conductive fluid or the like is not filled into the perforations of the predetermined pattern formed on the screen mask during film formation, there is a risk of film formation failure.

[0006] Here, by using the liquid pressure of the plating solution to press the screen mask through the electrolyte membrane, it is possible to cause the plating solution to seep out from the electrolyte membrane and fill the perforated areas with this seeped-out plating solution. However, such filling takes a long time, and as a result, it takes a long time to form the metal film.

[0007] The present invention has been made in view of these points, and aims to provide a method for forming a metal film and an apparatus for forming the metal film, which can form a metal film having a predetermined pattern in a shorter time and stably using a screen mask. [Means for solving the problem]

[0008] In view of the above problems, the present invention provides a method for forming a metal film, comprising: forming a metal film having a predetermined pattern on a substrate by electroplating with a screen mask sandwiched between an electrolyte membrane and a substrate, wherein the film formation method includes: a pressing step of covering the substrate with the screen mask having perforations of a predetermined pattern formed thereon, and pressing the substrate with the screen mask through the electrolyte membrane by the liquid pressure of the plating solution sealed inside the containment by the electrolyte membrane; and a film formation step of applying a film formation voltage between the anode inside the containment and the substrate, thereby allowing 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. The screen mask has a metal mesh portion with openings formed in a grid pattern, and a mask portion fixed to the metal mesh portion on the substrate side, with the perforations formed thereon. In the pressing step, while pressing the substrate with the mask portion, the positive electrode of the power supply is connected to the anode and the negative electrode of the power supply is connected to the metal mesh portion, and a filling voltage is applied between the anode and the metal mesh portion, thereby filling the through-hole portion with the plating solution that has seeped out from the electrolyte membrane.

[0009] In a more preferred embodiment, the screen mask is fixed to a metal frame at the periphery of the metal mesh portion, and the metal frame is electrically connected to the periphery of the metal mesh portion. In the pressing step, the filling voltage is applied between the anode and the metal mesh portion via the metal frame.

[0010] The metal film deposition apparatus according to the present invention is a film deposition apparatus that deposits a metal film of a predetermined pattern onto a substrate by electroplating with a screen mask sandwiched between an electrolyte membrane and a substrate. The film deposition apparatus comprises a container containing a plating solution containing metal ions, the plating solution sealed with the electrolyte membrane, a screen mask having perforations of the predetermined pattern formed therein and covering the substrate, a pressing mechanism that applies the liquid pressure of the plating solution in the container to the electrolyte membrane to press the substrate with the screen mask through the electrolyte membrane, an anode housed in the container and positioned spaced apart from the electrolyte membrane, and an electrical circuit for film deposition that applies a voltage between the anode and the substrate. The screen mask has a metal mesh portion with openings formed in a grid pattern and a mask portion fixed to the metal mesh portion on the substrate side and having the perforations formed therein. The anode is connected to the positive electrode, the metal mesh portion is connected to the negative electrode, and the apparatus includes a filling electrical circuit that fills the perforations of the plating solution seeping from the electrolyte membrane. The filling electrical circuit applies a voltage between the anode and the metal mesh portion before the film-forming electrical circuit applies a voltage between the anode and the substrate, while the substrate is being pressed by the pressing mechanism.

[0011] In a more preferred embodiment, the film deposition apparatus includes a metal frame on which the screen mask is fixed at the periphery of the metal mesh portion. The metal frame is electrically connected to the periphery of the metal mesh portion, and the filling electrical circuit applies the voltage between the anode and the metal mesh portion via the metal frame. [Effects of the Invention]

[0012] According to the film deposition method and apparatus of the present invention, a metal film having a predetermined pattern can be deposited stably in a shorter time using a screen mask. [Brief explanation of the drawing]

[0013] [Figure 1](a) is a schematic cross-sectional view showing an example of a metal film deposition apparatus according to an embodiment of the present invention, (b) is a schematic perspective view of a screen mask, and (c) is a partially enlarged cross-sectional view along line AA of (b). [Figure 2] This is a flowchart illustrating an example of a method for forming a metal film according to an embodiment of the present invention. [Figure 3] (a) is a schematic cross-sectional view illustrating the pressing process shown in Figure 2, and (b) is a schematic cross-sectional view illustrating the film formation process shown in Figure 2. [Modes for carrying out the invention]

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

[0015] As shown in Figure 1, the film deposition apparatus 1 is a film deposition apparatus that deposits a metal film F of a predetermined pattern P onto a substrate B by electroplating, with a mask structure 60 sandwiched between the electrolyte membrane 13 and the substrate B. Specifically, the film deposition apparatus 1 comprises an anode 11, an electrolyte membrane 13, and a power supply 14 that applies a voltage between the anode 11 and the substrate B.

[0016] The film deposition apparatus 1 comprises a housing 15 containing an anode 11 and a plating solution L, a mounting table 40 on which a substrate B is placed, and a mask structure 60 positioned on the surface of the substrate B. The film deposition apparatus 1 further comprises a linear actuator 70 for raising and lowering the housing 15. The linear actuator 70 has a rod 72 that moves linearly with respect to the main body 71, and the housing 15 is fixed to the tip of the rod 72. In this embodiment, for the sake of explanation, the electrolyte membrane 13 is positioned below the anode 11, and the mask structure 60 and substrate B are positioned further below it. However, the positional relationship between the electrolyte membrane 13 and the substrate B is not particularly limited as long as a metal film F can be deposited on the surface of the substrate B.

[0017] The base material B functions as a cathode. The base material B is a plate-shaped base material. In the present embodiment, the base material B is a rectangular base material. Among the surfaces of the base material B, the opposing surface Ba facing the electrolyte membrane 13 (screen mask 62) is the film-forming surface that functions as a cathode. As long as it functions as a cathode (i.e., a surface having conductivity), the material of the base material B is not particularly limited. The base material B may be made of a metal material such as aluminum or copper, for example. When forming a wiring pattern from the metal film F, the base material B uses a base material having an underlayer such as copper formed on the surface of an insulating base material such as resin. In this case, after the formation of the metal film F, the underlayer other than the portion where the metal film F is formed is removed by etching or the like. Thereby, a wiring pattern made of the metal film F can be formed on the surface of the insulating base material.

[0018] The anode 11 is, as an example, a non-porous anode made of the same metal as the metal of the metal film. The anode 11 has a block shape or a flat plate shape. The anode 11 is housed in the container 15 and is arranged so as to be separated from the electrolyte membrane 13. The anode 11 may be a porous body, a mesh, or a cage housing a plurality of balls. Examples of the material of the anode 11 include copper. The anode 11 dissolves when the voltage of the power source 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.

[0019] 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 base material B via the mounting table 40, and further connected to the metal mesh portion 64 of the screen mask 62 described later.

[0020] The plating solution L is a solution containing the metal of the metal film to be formed in an ionic state. Examples of such metals include copper, nickel, gold, or silver. 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, sulfamic acid, or pyrophosphoric acid. Examples of the solvent of the solution include water and alcohol. For example, when the metal is copper, the plating solution L may include an aqueous solution containing copper sulfate, copper pyrophosphate, etc.

[0021] The electrolyte membrane 13 is a membrane that can be impregnated (contain) metal ions inside 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 source 14, the material of the electrolyte membrane 13 is not particularly limited as long as the metal ions in the plating solution L can move to the substrate 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 5 μm to 200 μm. More preferably, the film thickness is in the range of 20 μm to 60 μm.

[0022] The container 15 is made of a material insoluble in the plating solution L. In the container 15, a storage space 15a for storing the plating solution L is formed. The anode 11 is disposed in the storage space 15a of the container 15. An opening 15d is formed on the side of the substrate B in the storage space 15a. The opening 15d of the container 15 is covered with the electrolyte membrane 13.

[0023] As shown in Figures 1(a) and 3(a), the linear actuator 70 raises and lowers the housing 15 by linearly moving the rod 72 so that the electrolyte membrane 13 and the mask structure 60 can move toward and away from each other. In this embodiment, a metal mounting base 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, a hydraulic or pneumatic actuator may be used instead of an electric actuator.

[0024] The housing 15 has a supply port 15b for supplying the plating solution L to the housing space 15a. The housing 15 also has a discharge port 15c for discharging the plating solution L from the housing space 15a. The supply port 15b and the discharge port 15c are holes communicating with the housing space 15a. The supply port 15b and the discharge port 15c are formed on either side of the housing space 15a. The supply port 15b is connected to the supply pipe 51. The discharge port 15c is fluidly connected to the discharge pipe 52.

[0025] The film deposition apparatus 1 further comprises a tank 90, a supply pipe 51, a discharge pipe 52, and a pump 80. As shown in Figure 1(a), the tank 90 contains the plating solution L. The supply pipe 51 connects the tank 90 to the container 15. The supply pipe 51 is connected to the pump 80. The pump 80 supplies the plating solution L from the tank 90 to the container 15. The discharge pipe 52 connects the tank 90 to the container 15. The discharge pipe 52 is connected to the pressure regulating valve 54. The pressure regulating valve 54 adjusts the pressure (liquid pressure) of the plating solution L in the container space 15a to a predetermined pressure.

[0026] In this embodiment, the plating solution L is drawn from the tank 90 into the supply pipe 51 by driving the pump 80. The drawn-in plating solution L is pumped from the supply port 15b to the containment space 15a. The plating solution L in the containment space 15a is returned to the tank 90 via the discharge port 15c. A circulation path 50 for circulating the plating solution L can be formed between the tank 90 and the containment body 15.

[0027] 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 applies the liquid pressure of the plating solution L to the electrolyte membrane 13, and through the electrolyte membrane 13, the screen mask 62 of the mask structure 60 presses the substrate B. In this embodiment, the pump 80 and the pressure regulating valve 54 correspond to the "pressing mechanism" as defined in the present invention.

[0028] The mask structure 60 comprises a metal frame 61 and a screen mask 62. The screen mask 62 has through-portions 68 formed in it according to a predetermined pattern P of the metal film F. The screen mask 62 comprises a metal 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 by the metal frame 61 on the surface of the metal frame 61 that faces the substrate B (opposing surface).

[0029] The metal mesh portion 64 is fixed to the metal frame 61. The metal mesh portion 64 is stretched with a predetermined tension so as to cover the opening of the metal frame 61. The metal mesh portion 64 has multiple openings 64c formed in a grid pattern. The metal mesh portion 64 is woven in a mesh pattern so as to intersect multiple oriented wires 64a and 64b. Multiple wires 64a are arranged with gaps between them, and multiple intersecting wires 64b are also arranged with gaps between them. As a result, multiple openings 64c are formed in a grid pattern in the metal mesh portion 64. The material of the wires 64a and 64b is not particularly limited as long as it is corrosion-resistant to the plating solution L and is conductive. Examples of materials for the wires 64a and 64b include stainless steel and other metallic materials.

[0030] The mask portion 65 is fixed to the metal mesh portion 64 on the side facing the substrate B (the side facing the substrate B) of the metal 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 of the mask portion 65 is not particularly limited as long as it can adhere to the substrate B. It is preferable that the mask portion 65 undergoes compressive elastic deformation due to pressure from the electrolyte membrane 13. For example, the material of the mask portion 65 can be a resin material such as acrylic resin, vinyl acetate resin, polyvinyl resin, polyimide resin, or polyester resin, or a rubber material such as silicone rubber. 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.

[0031] The metal frame 61 supports the periphery of the screen mask 62 with its opposing surface facing the base material B (mounting base 40). Specifically, the metal frame 61 fixes the screen mask 62 at the periphery of the metal mesh portion 64, and the metal frame 61 is electrically connected to the periphery of the metal mesh portion 64. In this embodiment, the mask structure 60 and the housing 15 are separate entities, but for example, the metal frame 61 may be fitted into the opening 15d of the housing 15, and the mask structure 60 and the housing 15 may be integrated. This not only allows the screen mask 62 to be attached to the housing 15, but also allows the screen mask 62 to support the deflection of the electrolyte membrane 13 due to the weight of the plating solution L contained in the housing 15.

[0032] The screen mask 62 is fixed to the metal frame 61. In this embodiment, the screen mask 62 has a rectangular outer shape. Therefore, the metal frame 61 has a rectangular frame-like shape. The material of the metal 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 metal frame 61 can be a metal material such as stainless steel. The metal frame 61 is formed, for example, by punching out a metal plate and has a thickness of about 1 mm to 3 mm.

[0033] The film deposition apparatus 1 has a positive electrode of a power supply 14 connected to the anode 11, and a negative electrode of the power supply 14 connected to the substrate B, and is equipped with an electrical circuit 16A for film deposition that applies a voltage between the anode 11 and the substrate B. Furthermore, the film deposition apparatus 1 has a positive electrode of the power supply 14 connected to the anode 11, and a negative electrode of the power supply 14 connected to the metal mesh portion 64, and is equipped with a filling electrical circuit 16B that applies a voltage between the anode 11 and the metal mesh portion 64, as will be described later.

[0034] The electrical circuit 16A for film formation is a circuit that forms a metal film F by applying a voltage between the anode 11 and the substrate B, thereby passing metal ions contained in the plating solution L in the container 15 through the electrolyte membrane 13 and depositing them on the surface of the substrate B.

[0035] The filling electrical circuit 16B is a circuit that fills the through-hole 68 with the plating solution La that has seeped out from the electrolyte film 13 by applying a voltage between the anode 11 and the metal mesh portion 64. The filling electrical circuit 16B applies a voltage between the anode 11 and the metal mesh portion 64 via the metal frame 61. As a result, the periphery of the metal mesh portion 64 is conductive to the metal frame 61, so a uniform voltage can be applied to the metal mesh portion 64 via the metal frame 61. Since the film deposition electrical circuit 16A and the filling electrical circuit 16B are parallel circuits connected to the power supply 14, the voltage for film deposition and the voltage for filling can be applied from the same power supply 14.

[0036] The steps of the film formation method shown in Figure 2 will be explained below with reference to Figures 1(a) and 3(a) and (b) described above. In this film formation method, a screen mask 62 on which through portions 68 of a predetermined pattern P are formed is sandwiched between the electrolyte film 13 and the substrate B, and a metal film F of the predetermined pattern P is formed on the surface of the substrate B by electroplating.

[0037] First, the placement process S1 is performed. In this process, the base material B is placed on the placement table 40. Specifically, the base material B is placed in the recess 41 of the placement table 40. Next, the pressing process S2 is performed. In this process, as shown in Figure 3(a), the base material B is covered with a screen mask 62, and the base material B is pressed by the screen mask 62 through the electrolyte membrane 13 by the liquid pressure of the plating solution L sealed inside the container 15 with the electrolyte membrane 13. Specifically, first, as shown in Figure 1(a), the mask structure 60 is placed on the base material B. This allows the screen mask 62, which has a predetermined pattern P through-hole 68 formed on it, to be placed on the base material B.

[0038] Next, the linear actuator 70 is driven to move the housing 15 toward the mounting base 40, bringing the electrolyte membrane 13 into contact with the mask structure 60. By driving the pump 80, the plating solution L is supplied to the housing space 15a of the housing 15. The pressure of the plating solution L in the housing space 15a becomes the pressure set by the pressure regulating valve 54.

[0039] Next, as shown in Figure 3(a), the filling electrical circuit 16B is closed while the substrate B is pressed with the mask portion 65. At this time, the film deposition electrical circuit 16A is open. Specifically, with the positive terminal of the power supply 14 connected to the anode 11 and the negative terminal of the power supply 14 connected to the metal mesh portion 64, a filling voltage is applied between the anode 11 and the metal mesh portion 64. At this time, the voltage is not yet applied between the anode 11 and the substrate B by the film deposition electrical circuit 16A. In this embodiment, since the metal frame 61 is conductive to the periphery of the metal mesh portion 64, the filling voltage can be stably applied between the anode 11 and the metal mesh portion 64 by the filling electrical circuit 16B via the metal frame 61.

[0040] When a filling voltage is applied, the metal mesh portion 64 becomes the cathode, and metal ions from the plating solution L in the containment space 15a move from the anode 11 side to the metal mesh portion 64 side and pass through the electrolyte membrane 13. As these metal ions pass through, water molecules contained in the plating solution L also move to the electrolyte membrane 13, and the plating solution L seeps out from the electrolyte membrane 13. The plating solution La seeping out from the electrolyte membrane 13 is pushed into the through-holes 68 formed in the screen mask 62 by the liquid pressure of the plating solution L in the containment space 15a via the electrolyte membrane 13. In this way, the plating solution La seeping out from the electrolyte membrane 13 fills the through-holes 68. By applying a filling voltage between the anode 11 and the metal mesh portion 64 using the filling electrical circuit 16B, the plating solution La can be quickly filled into the through-holes 68 of the screen mask 62.

[0041] Furthermore, if the screen mask 62 is placed on the surface of the substrate B and the surrounding atmosphere is reduced pressure, the plating solution La can easily fill the through-holes 68. In addition, if a groove or hole for air venting is provided on the surface of the screen mask 62 that communicates with the outside from the through-holes 68, the air in the through-holes 68 can be easily replaced with the plating solution La.

[0042] Here, for example, the film deposition apparatus 1 may be equipped with a voltmeter (not shown) for measuring the voltage between the anode 11 and the substrate B. In this case, with a constant current (a current of a certain magnitude) flowing between the anode 11 and the substrate B, the voltage acting between the anode 11 and the substrate B is measured with the voltmeter (not shown). When the measured voltage falls below a preset value, it is determined that the plating solution L has filled the through-hole 68, and the process may proceed to the film deposition process S3.

[0043] If the through-holes 68 of the screen mask 62 are not filled with the plating solution La, even if the power supply 14 is controlled to flow a constant current between the anode 11 and the substrate B, the current will not flow easily, and the voltage between the anode 11 and the substrate B will be higher than the voltage during normal film formation. Therefore, in such cases, the current between the anode 11 and the substrate B is released, and the liquid pressure of the plating solution L in the container 15 is continuously maintained. After a predetermined time has elapsed, the voltage acting between the anode 11 and the substrate B is measured again in the same manner to determine whether the through-holes 68 have been filled with the plating solution L. The current is supplied and the voltage is measured intermittently until it is determined that the through-holes 68 have been filled with the plating solution L.

[0044] Next, the film formation process S3 is performed. Here, as shown in Figure 3(b), with the substrate B pressed by the screen mask 62, the filling electrical circuit 16B is opened, and then the film formation electrical circuit 16A is closed. This applies a film formation voltage between the anode 11, which is in contact with the plating solution L, and the substrate B. As a result, metal ions contained in the plating solution L pass through the electrolyte membrane 13, and a metal film F derived from the metal ions is formed on the substrate B in a predetermined pattern P.

[0045] In this way, by driving the pump 80 in the circulation path between the tank 90 where the plating solution L is stored and the containment 15, the plating solution L can be circulated while a metal film F is formed. The liquid pressure of the plating solution L in the containment space 15a also acts on the plating solution La that seeps out from the electrolyte membrane 13, so a homogeneous metal film F can be formed under constant liquid pressure. During film formation, when a voltage is applied, water molecules contained in the plating solution L pass through the electrolyte membrane 13 along with metal ions passing through the electrolyte membrane 13, so that moisture is stably secured in the perforation portion 68 of the screen mask 62. As a result, metal ions can be stably deposited on the surface of the substrate B.

[0046] In the film formation process S3, a metal film F of a predetermined thickness is formed by applying current for a predetermined time, and then the separation process S4 is performed. In this process, the pump 80 is stopped, the plating solution L is discharged from the containment space 15a, and then the linear actuator 70 is driven to move the containment 15 away from the mounting table 40, separating the electrolyte membrane 13 from the mask structure 60. The mask structure 60 is removed from the surface of the substrate B, and the substrate B is removed from the mounting table 40. Through this series of operations, a substrate B with a metal film F of a predetermined pattern P can be obtained.

[0047] In this embodiment, the voltage applied by the filling electrical circuit 16B may be the same as the voltage applied by the film-forming electrical circuit 16A during film formation. However, the voltage applied by the filling electrical circuit 16B is not particularly limited, as long as no damage occurs to the electrolyte membrane 13 and the metal mesh portion 64. Furthermore, by applying the filling voltage, metal derived from the plating solution L is deposited on the surface of the metal mesh portion 64. For example, at a maintenance timing (at a timing other than the series of steps shown in Figure 2), a reverse voltage may be applied to the anode 11 and the metal mesh portion 64 to dissolve the metal deposited on the metal mesh portion 64.

[0048] [Examples] As a substrate for film formation, a glass epoxy substrate was prepared by impregnating a layer of glass fiber cloth with epoxy resin. Copper foil was formed on the surface of this glass epoxy substrate. Next, a copper film was formed using the film formation apparatus shown in Figure 1. A copper sulfate aqueous solution containing 1 M CuSO4 and 0.2 M H2SO4 was used as the plating solution. A Cu plate was used as the anode. DuPont's Nafion® was used as the electrolyte membrane. The liquid pressure of the plating solution was set to 0.2 MPa, and the substrate was pressed with a screen mask through the electrolyte membrane. In this pressed state, a total area of ​​1800 mm² was applied to the screen mask. 2 When a filling voltage was applied to the through-hole formed by the process, the time it took for the plating solution to fill the hole was measured, and the filling time was 32.5 seconds.

[0049] [Comparative Example] Similar to the example, the time it took for the plating solution to fill the screen mask was measured. The only difference from the example was that no filling voltage was applied. When the time it took for the plating solution to fill the perforations was measured with the screen mask pressed against the electrolyte membrane, the filling time was 70 seconds.

[0050] From the above results, it is considered that, as in the example, by applying a filling voltage while the liquid pressure of the plating solution contained in the container is acting on the electrolyte membrane, the plating solution contained in the container moves through the electrolyte membrane to the screen mask. As a result, it is considered that the plating solution filled the perforations of the screen mask more quickly in the example. [Explanation of Symbols]

[0051] 1: Film deposition apparatus, 13: Electrolyte membrane, 14: Power supply, 15: Housing, 16A: Electrical circuit for film deposition, 16B: Electrical circuit for filling, 40: Mounting platform, 61: Metal frame, 62: Screen mask, 64: Metal mesh portion, 65: Mask portion, 68: Through portion, B: Substrate, F: Metal film, L: Plating solution, P: Predetermined pattern

Claims

1. A film formation method in which a metal film having a predetermined pattern is formed on a substrate by electroplating with a screen mask sandwiched between the electrolyte membrane and the substrate, The aforementioned film formation method is A pressing step is performed in which the substrate is covered with the screen mask on which a predetermined pattern of perforations is formed, and the substrate is pressed by the screen mask through the electrolyte membrane by the liquid pressure of the plating solution sealed inside the container by the electrolyte membrane, The process includes a film formation step in which a film formation voltage is applied between the anode in the containment and the substrate, thereby allowing metal ions contained in the plating solution to pass through the electrolyte membrane, and a metal film derived from the metal ions is formed on the substrate in a predetermined pattern, The screen mask has a metal mesh portion with openings formed in a grid pattern, and a mask portion fixed to the metal mesh portion on the substrate side, with the through portion formed therein. A method for forming a metal film, characterized in that, in the pressing step, while pressing the substrate with the mask portion, the positive electrode of the power supply is connected to the anode and the negative electrode of the power supply is connected to the metal mesh portion, and a filling voltage is applied between the anode and the metal mesh portion, thereby filling the through-hole portion with the plating solution that has seeped out from the electrolyte membrane.

2. The screen mask is fixed to the metal frame at the periphery of the metal mesh portion. The metal frame is electrically connected to the periphery of the metal mesh portion. The method for forming a metal film according to claim 1, characterized in that, in the pressing step, the filling voltage is applied between the anode and the metal mesh portion via the metal frame.

3. A film deposition apparatus for forming a metal film of a predetermined pattern on a substrate by electroplating, with a screen mask sandwiched between the electrolyte membrane and the substrate, The aforementioned film deposition apparatus is A container in which a plating solution containing metal ions is contained and the plating solution is sealed with the electrolyte membrane, A screen mask is formed in which the predetermined pattern is penetrated and covers the substrate, A pressing mechanism that applies the liquid pressure of the plating solution in the containment to the electrolyte membrane, thereby pressing the substrate with the screen mask via the electrolyte membrane, An anode housed in the aforementioned container and positioned spaced apart from the electrolyte membrane, The system comprises an electrical circuit for film formation that applies a voltage between the anode and the substrate, The screen mask has a metal mesh portion with openings formed in a grid pattern, and a mask portion fixed to the metal mesh portion on the substrate side, with the through portion formed therein. The anode is connected to the positive electrode, the metal mesh portion is connected to the negative electrode, and the circuit comprises a filling electrical circuit for filling the through-hole portion with the plating solution seeping out from the electrolyte membrane. The electrical circuit for filling is characterized in that, while the substrate is pressed by the pressing mechanism with the mask portion, a voltage is applied between the anode and the metal mesh portion before the electrical circuit for film formation applies a voltage between the anode and the substrate.

4. The film deposition apparatus includes a metal frame that secures the screen mask at the periphery of the metal mesh portion. The metal frame is electrically connected to the periphery of the metal mesh portion. The metal film deposition apparatus according to claim 3, characterized in that the filling electrical circuit applies the voltage between the anode and the metal mesh portion via the metal frame.

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