Metallic film deposition apparatus

Abstract

To provide a metallic film deposition apparatus that can remove a gas attached on an anode during deposition.SOLUTION: A deposition apparatus 1 for depositing a metallic film F on a substrate B contacting a polymer electrolyte 13 by electrolytic plating, comprises: an anode 11; a container 15 for accommodating the anode 11 and a plating solution L; and a polymer electrolyte 13 arranged at the opposite position of the anode 11 for covering an opening 15d of the container 15. The anode 11 has multiple penetrating parts 11c. A movable brush member 12 is arranged on an underside surface 11b among the surfaces of the anode 11 so as to contact the underside surface 11b that is positioned on the opposite side of an opposite surface 11a facing the polymer electrolyte 13.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a film forming apparatus for forming a metal film by electrolytic plating using an electrolyte membrane. [Background technology]

[0002] Conventionally, as this type of film forming apparatus, a film forming apparatus has been proposed in which an anode and a plating solution are contained in a container, and an opening of the container formed at a position opposite the anode is covered with an electrolyte membrane (see, for example, Patent Document 1). When forming a metal film on a substrate using this film forming apparatus, a voltage is applied to the anode and the surface of the substrate with the substrate in contact with the electrolyte membrane. As a result, metal ions contained in the plating solution pass through the electrolyte membrane and are reduced on the surface of the substrate, causing the metal to precipitate, forming a metal film. During film formation, water and other substances contained in the plating solution decompose to generate gas on the surface of the anode, so the film forming apparatus is provided with a vibration unit that vibrates the anode. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-169399 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the technology of Patent Document 1, the gas generated on the surface of the anode can be desorbed from the surface of the anode by the vibration energy of the vibrating part and the buoyancy in the plating solution, but it is difficult to remove the gas from the anode when the gas is fine or depending on the location where it is attached to the anode. In particular, if gas remains in the container, it is difficult to stably form a metal film while pressurizing the plating solution to a desired pressure because gas is a compressible fluid.

[0005] The present invention has been made in consideration of the above-mentioned points, and an object of the present invention is to provide a metal film forming apparatus that can remove gas that adheres to the anode during film formation. [Means for solving the problem]

[0006] In view of the above problems, the metal film forming apparatus of the present invention comprises an anode, a container that contains a plating solution together with the anode, and an electrolyte membrane that covers an opening of the container formed at a position opposite the anode, and forms a metal film on a substrate in contact with the electrolyte membrane by electrolytic plating, wherein the anode is an anode having a plurality of through-holes formed therein, and a movable brush member that comes into contact with the back surface of the anode, the back surface being located on the opposite side to the opposing surface that faces the electrolyte membrane. Effect of the Invention

[0007] According to the present invention, the gas adhering to the anode can be removed by moving the movable brush member while keeping the brush member in contact with the anode. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2A is a schematic diagram of a film-forming apparatus for a metal film according to the present embodiment, and FIG. 2B is a schematic diagram for explaining removal of gas adhering to an anode of the film-forming apparatus shown in FIG. [Diagram 2] FIG. 1A is a schematic diagram of a film-forming apparatus for a metal film according to a modified example, and FIG. 1B is a schematic diagram for explaining removal of gas adhering to an anode of the film-forming apparatus shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] 1(a) and 1(b), the film formation apparatus 1 is a film formation apparatus that forms a metal film F on a substrate B by electrolytic plating. The film formation apparatus 1 includes an anode 11, an electrolyte membrane 13, and a power source 14 that applies a voltage between the anode 11 and the substrate B. The film formation apparatus 1 further includes a container 15 that contains the anode 11 and a plating solution L, a mounting table 40 on which the substrate B is placed, and a pressurizing device 60 that pressurizes the plating solution L in the container 15.

[0010] The film forming apparatus 1 includes a linear actuator 70 that raises and lowers the container 15. The linear actuator 70 is provided with a linear rod 72 that moves linearly relative to a main body 71. The container 15 can be raised and lowered by vertically moving the linear rod 72 attached to the tip of the container 15 relative to the main body 71.

[0011] The substrate B functions as a cathode. The substrate B is a plate-shaped substrate. Of the surfaces of the substrate B, the surface facing the electrolyte membrane 13 is a film formation surface that functions as a cathode. The plating solution L is a liquid that contains the metal of the metal coating F to be formed in an ionic state. An example of such a metal is copper. The plating solution L is a solution in which these metals are dissolved (ionized) with sulfuric acid or the like.

[0012] In this embodiment, the anode 11 is an insoluble anode that does not dissolve in the plating solution L. Examples of the material of the anode 11 include titanium, a titanium alloy, and platinum. When the material of the anode is titanium or a titanium alloy, the surface of the anode may be coated with iridium oxide or platinum. By carrying out these coatings, the reduction reaction of water is promoted, and metal is easily deposited on the surface of the base material B, but on the other hand, oxygen gas (gas) is easily generated by electrolysis of water in the anode 11. The anode 11 has a plurality of through-portions 11c penetrating in the thickness direction. However, the anode 11 may be a cage filled with insoluble metal balls. In this case, through-portions are formed between the metal balls.

[0013] The container 15 is made of a material that is insoluble in the plating solution L. The container 15 has a container space 15a for accommodating the plating solution L. The anode 11 is disposed in the container space 15a of the container 15 via a support member 18. An opening 15d is formed on the substrate B side (lower side) of the container space 15a. With the opening 15d covered by the electrolyte membrane 13, the electrolyte membrane 13 is fixed to the container 15 by a frame 17.

[0014] The accommodation body 15 has a supply port 15b and a discharge port 15c for supplying the plating solution L to the accommodation space 15a and discharging the plating solution L from the accommodation space 15a, at positions sandwiching the anode 11 in the accommodation space 15a. The film forming apparatus 1 further includes a tank 90, a pump 80, and an on-off valve 54. As shown in FIG. 1, the plating solution L is accommodated in the tank 90. ​​By opening and closing the on-off valve 54, the plating solution L in the tank 90 can be caused to flow through the circulation path 50 by the pump 80, thereby replacing the plating solution L in the accommodation space 15a.

[0015] Furthermore, a pressurizing device 60 that pressurizes the plating solution L in the accommodation space 15a during film formation is connected to the accommodation body 15. The plating solution L in the accommodation space 15a can be pressurized by discharging the plating solution L in a cylinder 61 of the pressurizing device 60 with a piston 62.

[0016] In this embodiment, a movable brush member 12 is disposed on the back surface 11b of the anode 11, which is located on the opposite side to the opposing surface 11a that faces the electrolyte membrane 13. The brush member 12 is a member in which a brush portion 12b is attached to a flat support 12a, and a tip of the brush portion 12b is in contact with the back surface 11b of the anode 11. The support 12a is attached to a driving device such as a motor 19 via a rotary-linear motion conversion mechanism (not shown). By driving the motor 19, the brush portion 12b reciprocates along the back surface 11b of the anode 11. The brush member 12 is made of an insulating material, and is preferably made of a material that is resistant to the plating solution L.

[0017] 1(b), in a state in which the plating solution L is pressurized by a pressure device 60, the electrolyte membrane 13 is pressed against the substrate B, and a voltage is applied between the anode 11 and the substrate B by a power source 14. As a result, a metal film F is formed on the substrate B. At this time, gas G is generated by electrolysis on the opposing surface 11a of the anode 11, and the generated gas G passes through the through portion 11c of the anode 11 and adheres to the back surface 11b of the anode 11.

[0018] In this embodiment, for example, after the film is formed, the motor 19 is driven to reciprocate the brush member 12, so that the gas G adhering to the anode 11 can be physically removed by the brush part 12b. The removed gas G rises due to buoyancy and moves along the upper wall surface 15f inclined upward toward the discharge port 15c.

[0019] When the plating solution L in the storage space 15a is replaced by driving the pump 80, the remaining gas G remaining in the storage space 15a is also sent to the discharge port 15c by the liquid flow of the plating solution L. The gas G discharged from the discharge port 15c is discharged to the tank 90. ​​By discharging the gas G in the storage space 15a in this manner, at the time of the next film formation, the metal film F can be formed in a state in which the pressurization of the plating solution L by the pressurizing device 60 is stabilized. The gas generated on the opposing surface 11a of the anode 11 may be moved to the penetration portion 11c by vibration caused by moving the brush member 12.

[0020] 2(a) and (b) has a different structure for the brush member 12A. In this modification, the brush member 12A is a rotating member that rotates due to the liquid flow of the plating liquid L. The brush member 12A is equipped with a fan 12c that rotates due to the liquid flow of the plating liquid L, and a plurality of blades 12d attached to the outer periphery of the fan 12c. The blades 12d are flexible, and their tips are in contact with the back surface 11b of the anode 11.

[0021] In this modification, when the plating solution L in the storage space 15a is replaced by driving the pump 80, the flow of the plating solution L rotates each brush member 12A, and the vanes 12d physically remove the gas G adhering to the anode 11. The removed gas G rises due to buoyancy, flows together with the plating solution L toward the discharge port 15c, and is discharged from the discharge port 15c to the tank 90. ​​In this modification, by discharging the gas G in the storage space 15a, the metal film F can be formed in a state in which the pressurization of the plating solution L by the pressurizing device 60 is stabilized at the time of the next film formation.

[0022] In this embodiment, the gas adhering to the anode is removed by the brush member, but the gas may be removed, for example, by using a spring or buoyancy to raise the anode together with the support member to the gas-filled space of the accommodation space, and then immersing the anode again in the plating solution. In addition, the gas adhering to the anode may be removed by spraying the plating solution from a nozzle disposed in the accommodation space onto the back surface of the anode, or by directly spraying the plating solution supplied from a supply port onto the back surface of the anode. In addition, the gas adhering to the anode may be removed by moving the anode together with the support member. [Explanation of symbols]

[0023] 1: Metal film forming device, 11: Anode, 11a: Opposing surface, 11b: Back surface, 11c: Penetration portion, 12: Brush member, 13: Electrolyte membrane, 15: Container, 15d: Opening, F: Metal film, L: Plating solution

Claims

[Claim 1] A metal film forming apparatus including an anode, a container that contains a plating solution together with the anode, and an electrolyte membrane that covers an opening of the container that is formed at a position facing the anode, and that forms a metal film on a base material in contact with the electrolyte membrane by electrolytic plating, The anode is an anode having a plurality of through-holes formed therein, A metal film forming apparatus characterized in that a movable brush member is disposed on the back surface of the anode, the back surface being opposite the opposing surface facing the electrolyte membrane.

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