Film formation apparatus

Abstract

To suppress the occurrence of a plating defect while achieving optimal film formation.SOLUTION: In a film formation apparatus that forms a coating on a conductive workpiece using an electrolyte, the apparatus comprises an electrolyte tank for storing the electrolyte, a workpiece support section for supporting the conductive workpiece immersed in the electrolyte, an insulating workpiece-side shield plate attached to the conductive workpiece, and an insulating tank-side shield plate disposed vertically opposite the workpiece-side shield plate on the bottom of the electrolyte tank, the work-side shield plate is provided at its lower portion facing the tank-side shield plate and has an air accumulation section, the tank-side shield plate is positioned protruding upward from the electrolyte liquid surface formed in the air pocket section, partitioning the inner lower tank space that faces the conductive workpiece vertically from the outer lower tank space located outside the inner lower tank space, and the workpiece-side shielding plate further has an electrolyte passage hole that allows the electrolyte in the inner lower tank space to flow toward the conductive workpiece.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a film forming device that forms a film on a conductive workpiece using an electrolyte. [Background technology]

[0002] BACKGROUND ART Conventionally, as a film forming apparatus, an electrolytic plating method is known in which a plating process is performed on a workpiece immersed in a plating solution (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-224278 Summary of the Invention [Problem to be solved by the invention]

[0004] In electroplating such as that described in Patent Document 1, plating defects such as excessive metal deposition can occur due to current concentration depending on the location of the conductive workpiece to be plated. To prevent excessive deposition, a shielding plate is typically used to prevent localized current concentration, thereby preventing current concentration. When providing such a shielding plate, openings are provided in the shielding plate to allow the plating solution to flow through. However, to further prevent current concentration, complete shielding without providing openings in the shielding plate can be considered. However, complete shielding can result in insufficient supply and diffusion of plating solution, resulting in poor film formation.

[0005] Therefore, an object of the present disclosure is to provide a film forming apparatus that can preferably form a film while suppressing the occurrence of plating defects. [Means for solving the problem]

[0006] The film forming apparatus of the present disclosure is a film forming apparatus that forms a film on a conductive workpiece using an electrolyte, and includes an electrolyte tank that stores the electrolyte, a work support portion that supports the conductive workpiece immersed in the electrolyte, an insulating work-side shielding plate attached to the conductive workpiece, and an insulating tank-side shielding plate that is provided at the bottom of the electrolyte tank and arranged vertically opposite the work-side shielding plate, wherein the work-side shielding plate is provided at a lower portion opposite the tank-side shielding plate and has an air reservoir portion that accumulates air, and the tank-side shielding plate is provided so as to protrude upward from the liquid surface of the electrolyte formed in the air reservoir, thereby dividing the space into an inner lower tank space that faces the conductive workpiece in the vertical direction and an outer lower tank space that is located outside the inner lower tank space, and the work-side shielding plate further has an electrolyte passage hole that allows the electrolyte in the inner lower tank space to flow toward the conductive workpiece. [Effects of the Invention]

[0007] According to the present disclosure, film formation can be performed favorably while suppressing the occurrence of plating defects. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing a film forming apparatus according to this embodiment. [Figure 2] FIG. 2 is a view showing the upper shielding plate of the workpiece-side shielding plate. [Figure 3] FIG. 3 is a diagram showing an example of a lower shielding plate of the workpiece side shielding plate. [Figure 4] FIG. 4 is a diagram showing an example of the lower shielding plate of the workpiece side shielding plate. [Figure 5] FIG. 5 is a diagram showing an example of the lower shielding plate of the workpiece side shielding plate. [Figure 6] FIG. 6 is a diagram showing an example of a plating solution passage hole in the lower shielding plate. [Figure 7] FIG. 7 is a diagram showing an example of a plating solution passage hole in the lower shielding plate. [Figure 8]FIG. 8 is a diagram showing an example of a plating solution passage hole in the lower shielding plate. [Figure 9] FIG. 9 is a diagram illustrating an example of an electrolyte supply unit. [Figure 10] FIG. 10 is a diagram illustrating an example of an electrolyte supply unit. [Figure 11] FIG. 11 is a diagram illustrating an example of an electrolyte supply unit. [Figure 12] FIG. 12 is a diagram showing an example of an outlet hole of the air supply unit. [Figure 13] FIG. 13 is a diagram showing an example of an outlet hole of the air supply unit. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. However, this disclosure is not limited to these embodiments. Furthermore, the components in the following embodiments include those that are easily replaceable by those skilled in the art, or those that are substantially identical. Furthermore, the components described below can be combined as appropriate, and when there are multiple embodiments, the respective embodiments can also be combined.

[0010] [Present embodiment] The film forming apparatus 1 according to this embodiment is an apparatus for forming a film on a conductive workpiece W as a target object using an electrolytic solution, and is, for example, an electroplating apparatus or an electroforming apparatus. In this embodiment, the film forming apparatus 1 is described as being applied to a plating apparatus that performs electroplating using a plating solution (electrolytic solution). The conductive workpiece W is a metal having electrical conductivity, and its shape is not particularly limited. In this embodiment, the conductive workpiece W is rotatably supported, and therefore has the shape of a rotating body such as a cylinder or a cylindrical column.

[0011] (Film forming device) Fig. 1 is a diagram of a film forming apparatus according to this embodiment. As shown in Fig. 1, the film forming apparatus 1 includes an electrolyte tank 10, a workpiece support unit 11, a plating metal 13, a workpiece-side shielding plate 15, a tank-side shielding plate 16, an air supply unit 17, an electrolyte supply unit 18, and an electrolyte discharge unit 19.

[0012] The electrolytic solution tank 10 is a tank that stores plating solution. A conductive workpiece W is immersed in the electrolytic solution tank 10. The workpiece support part 11 is provided vertically above the electrolytic solution tank 10 and supports the conductive workpiece W by suspending it. The workpiece support part 11 has a rotating shaft 21 that rotatably holds the conductive workpiece W. The rotating shaft 21 is arranged so that its axial direction is aligned vertically, and the conductive workpiece W is attached to its lower side. The plating metal 13 is placed in the electrolytic solution tank 10 and is immersed in the plating solution. The plating metal 13 serves as the anode and supplies metal ions to the plating solution. The conductive workpiece W serves as the cathode and forms a plating by the deposition of metal ions in the plating solution.

[0013] The work-side shielding plate 15 is an insulating shielding plate attached to the conductive workpiece W. The work-side shielding plate 15 has an upper shielding plate 24 arranged on the upper side of the conductive workpiece W, and a lower shielding plate 25 arranged on the lower side of the conductive workpiece W. In other words, the work-side shielding plate 15 has a structure divided into upper and lower two parts. Note that in this embodiment, the work-side shielding plate 15 has a two-part structure, but it may also be one piece.

[0014] FIG. 2 is a diagram showing the upper shielding plate of the work-side shielding plate. As shown in FIG. 2, the upper shielding plate 24 includes a cylindrical portion 24a and a disk portion 24b provided inside the cylindrical portion 24a. The cylindrical portion 24a has a larger diameter than the conductive workpiece W, and the upper portion of the conductive workpiece W is located inside the cylindrical portion 24a. The disk portion 24b faces the upper end surface of the conductive workpiece W and serves as a portion for attaching the cylindrical portion 24a to the conductive workpiece W. The disk portion 24b is formed with an attachment hole 31 for attaching the cylindrical portion 24a to the conductive workpiece W and a plating solution passing hole 32 for passing a plating solution therethrough. The plating solution passing hole 32 is formed on the periphery of the disk portion 24b, and the attachment hole 31 is formed closer to the center than the plating solution passing hole 32.

[0015] The upper shielding plate 24 is provided with an upper portion 24a1 that protrudes from the liquid level L (dashed line) of the plating solution in the electrolyte tank 10 across the disk portion 24b of the cylindrical portion 24a. The upper shielding plate 24 vertically separates an inner upper tank space E1 facing the conductive workpiece W from an outer upper tank space E2 located outside the inner upper tank space E1. Therefore, the upper shielding plate 24 blocks the current flowing through the plating solution between the inner upper tank space E1 and the outer upper tank space E2. The length of the upper shielding plate 24 that protrudes from the liquid level is higher than the liquid level of the plating solution that rises due to centripetal force when the conductive workpiece W rotates. The lower portion 24a2 of the upper shielding plate 24 is provided with a disk portion 24b of the cylindrical portion 24a that protrudes downward from the disk portion 24b. The lower portion 24a2 is provided facing the outer peripheral surface of the upper end portion of the conductive workpiece W. The lower portion 24a2 blocks the current flowing toward the upper end portion of the conductive workpiece W, thereby suppressing current concentration at the upper end portion of the conductive workpiece W.

[0016] The upper shielding plate 24 is attached to the conductive workpiece W by fastening it to the conductive workpiece W with fastening members via the mounting holes 31. In this embodiment, the upper shielding plate 24 is fastened to the conductive workpiece W using the mounting holes 31 formed in the disc portion 24b, but the position where the mounting holes 31 are provided is not particularly limited, and for example, the upper shielding plate 24 may be formed in a position where it can be attached to the outer peripheral surface of the conductive workpiece W. In other words, the upper shielding plate 24 may further have a portion that fits along the outer peripheral surface of the conductive workpiece W, and the mounting holes 31 may be formed in this portion. The outer surface of the fastening member that comes into contact with the electrolyte may be covered with an insulating sealant.

[0017] Next, the lower shielding plate 25 will be described with reference to FIG. 1. As shown in FIG. 1, the lower shielding plate 25 is disposed opposite the tank-side shielding plate 16 disposed below. The lower shielding plate 25 has an upper surface 25a, an air reservoir 25b disposed on the periphery of the upper surface 25a, and a protrusion 25c protruding from the upper surface 25a. The upper surface 25a faces the lower end surface of the conductive workpiece W and serves as a portion for attachment to the conductive workpiece W. The upper surface 25a is provided with an attachment hole (see FIG. 9) for attachment to the conductive workpiece W and a plating solution passage hole 42 for passing a plating solution therethrough. The plating solution passage hole 42 is formed around the conductive workpiece W to be attached.

[0018] As shown in FIG. 1, the air reservoir 25b is located opposite the tank-side shielding plate 16 located below. Specifically, the air reservoir 25b includes an air inner wall 45 and an air outer wall 46. The air inner wall 45 is located on the inner side of the tank-side shielding plate 16 in the horizontal direction, and protrudes downward from the upper surface 25a. The air outer wall 46 is located on the outer side of the tank-side shielding plate 16 in the horizontal direction, and protrudes downward from the upper surface 25a. In FIG. 1, the air inner wall 45 and the air outer wall 46 have the same length in the vertical direction protruding downward from the upper surface 25a. The air reservoir 25b is formed in an annular shape centered on the rotation shaft 21.

[0019] The protrusion 25c is provided to protrude upward from the upper surface 25a. The protrusion 25c is provided facing the outer peripheral surface of the lower end side of the conductive workpiece W, and is formed in an annular shape centered on the rotation shaft 21. The protrusion 25c blocks the current flowing toward the lower end of the conductive workpiece W, thereby suppressing current concentration at the lower end of the conductive workpiece W.

[0020] Next, another example of the lower shielding plate 25 will be described with reference to Figures 3 to 5. Figures 3 to 5 are diagrams showing an example of a lower shielding plate of a work-side shielding plate. As shown in Figure 3, the lower shielding plate 55 has different vertical lengths than the air inner wall 45 and the air outer wall 46 in Figure 1. Specifically, the lower end of the air outer wall 46 is located above the lower end of the air inner wall 45. In other words, the length of the air outer wall 46 protruding downward from the upper surface portion 25a is shorter than the length of the air inner wall 45. Therefore, the air accumulated in the air reservoir portion 25b is released to the outside of the air outer wall 46.

[0021] Next, another lower shielding plate 56 shown in Fig. 4 will be described. As shown in Fig. 4, the lower shielding plate 56 further has an air vent hole 57 formed through the air outer wall 46 of Fig. 1. The air vent hole 57 is formed through the air outer wall 46 in the horizontal direction and is formed at a position between the upper end of the tank-side shielding plate 16 and the lower end of the air outer wall 46 in the vertical direction. Therefore, air accumulated in the air reservoir portion 25b is released to the outside of the air outer wall 46 through the air vent hole 57.

[0022] Next, another lower shielding plate 58 shown in Fig. 5 will be described. As shown in Fig. 5, the lower shielding plate 58 has a tapered shape that widens downward, similar to the shape of the air outer wall 46 in Fig. 1. In this case, the air reservoir 25b has a downward opening that widens in the radial direction of the rotating shaft 21. Therefore, when the air reservoir 25b of the lower shielding plate 58 attached to the conductive workpiece W is placed opposite the tank-side shielding plate 16, physical contact between the lower shielding plate 58 and the tank-side shielding plate 16 can be suppressed.

[0023] Note that the air inner wall 45 of the lower shielding plate 58 may be structured to narrow the opening of the air accumulation portion 25b in order to suppress air leakage.

[0024] Next, an example of the plating solution passage holes 42 of the lower shielding plate 25 will be described with reference to FIGS. 6 to 8. FIGS. 6 to 8 are views showing an example of the plating solution passage holes of the lower shielding plate, and are top views when viewed from the axial direction of the rotation axis 21. First, the plating solution passage hole 42 in FIG. 6 will be described. The plating solution passage hole 42a shown in FIG. 6 is a hollow hole having a circular cross-section, and is provided in a plurality of equally spaced arrangements in the circumferential direction. The outer periphery of the plating solution passage hole 42a is located at a position away from the outer periphery of the conductive work W, and the distance between the center of the plating solution passage hole 42a and the outer periphery of the conductive work W is defined as da. Also, the distance between the centers of the plating solution passage holes 42a adjacent in the circumferential direction is defined as Wa. In this case, the plurality of plating solution passage holes 42a are arranged such that the relationship Wa < da holds.

[0025] The plating solution passage hole 42b shown in FIG. 7 is a slit opening that is long in the direction along the circumferential direction, and is provided in a plurality of equally spaced arrangements in the circumferential direction. The distance between the center of the plating solution passage hole 42a in the radial direction and the outer periphery of the conductive work W is defined as db. Also, the distance between the ends of the plating solution passage holes 42b adjacent in the circumferential direction is defined as Wb. In this case, the plurality of plating solution passage holes 42a are arranged such that the relationship Wb < db holds.

[0026] The plating solution passage hole 42c shown in FIG. 6 is a slit opening that is long in the direction along the circumferential direction, and is provided in a plurality of equally spaced arrangements in the circumferential direction and is arranged in a plurality of rows (for example, two rows) in the radial direction. One row of the plating solution passage holes 42c is arranged in a staggered manner such that the portion between the ends of the plating solution passage holes 42c adjacent in the circumferential direction is located at the center of the other row of the plating solution passage holes 42c.

[0027] Next, the tank-side shielding plate 16 will be described with reference to Fig. 1. The tank-side shielding plate 16 is an insulating shielding plate, similar to the work-side shielding plate 15. The tank-side shielding plate 16 is provided at the bottom of the electrolyte tank 10 and is arranged facing the lower shielding plate 25 of the work-side shielding plate 15 in the vertical direction. The tank-side shielding plate 16 is formed in a cylindrical shape, and its interior defines an inner lower tank space E3, while its exterior defines an outer lower tank space E4.

[0028] Specifically, the tank-side shielding plate 16 is provided on the air supply unit 17, which will be described later, and its upper end is positioned so as to protrude upward from the liquid surface of the plating solution formed in the opposing air reservoir 25b. Therefore, the tank-side shielding plate 16, by means of the air reservoir 25b, blocks the current flowing through the plating solution between the inner lower tank space E3 and the outer lower tank space E4.

[0029] The air supply unit 17 is provided to agitate the plating solution and remove foreign matter from the surface of the conductive workpiece W and the surface of the plating metal 13. The air supply unit 17 is provided at the bottom of the electrolyte tank 10, and a tank-side shielding plate 16 is arranged above it. The air supply unit 17 supplies air bubbles from the bottom of the electrolyte tank 10. The air supply unit 17 has multiple blow-out holes 71 for supplying air bubbles. The air supply unit 17 is provided across the inner lower tank space E3 and the outer lower tank space E4, which are partitioned by the tank-side shielding plate 16, and supplies air bubbles toward the inner lower tank space E3 and the outer lower tank space E4 via the multiple blow-out holes 71.

[0030] Next, an example of the plurality of blow-out holes 71 will be described with reference to Fig. 12 and Fig. 13. Fig. 12 and Fig. 13 are diagrams showing an example of blow-out holes of an air supply unit. As shown in Fig. 12, the plurality of blow-out holes 71 provided in the inner lower tank space E3 are provided in greater numbers at positions facing the air reservoir 25b than at positions not facing the air reservoir 25b. Specifically, the plurality of blow-out holes 71 are provided only at positions facing the air reservoir 25b and positions facing the plating solution passing holes 42 in the vertical direction.

[0031] Next, the blowout holes 71 of another air supply unit 17 shown in Fig. 13 will be described. As shown in Fig. 13, the multiple blowout holes 71 provided in the inner lower tank space E3 are provided only at positions facing the air reservoir 25b in the vertical direction. Note that, in Fig. 13, since the air vent hole 78 is provided in the upper surface 25a of the air reservoir 25b, it is possible to omit providing the blowout holes 71 at positions facing the plating solution passage holes 42.

[0032] Next, the electrolytic solution supply unit 18 will be described with reference to Fig. 1. The electrolytic solution supply unit 18 supplies a plating solution to the inner lower tank space E3. As shown in Fig. 1, the electrolytic solution supply unit 18 is provided with a plating solution supply pipe 61 that extends from the outside of the electrolytic solution tank 10 to the inner lower tank space E3 inside the electrolytic solution tank 10. In Fig. 1, the plating solution supply pipe 61 is arranged to extend horizontally, with the supply port side end being positioned at the center of the inner lower tank space E3.

[0033] Here, the electrolytic solution supply unit 18 may have the configuration shown in Figures 9 to 11. Figures 9 to 11 are diagrams showing an example of the electrolytic solution supply unit. The electrolytic solution supply unit 18 shown in Figures 9 to 11 supplies the plating solution to the inner lower tank space E3 in a dispersed manner.

[0034] 9, the electrolytic solution supply unit 18 has a shape in which the supply port side end of the plating solution supply pipe 61 is bent from the horizontal direction to the vertical direction upward. Therefore, the supply port 62 of the plating solution supply pipe 61 is positioned coaxially with the rotation shaft 21 and faces upward. In the inner lower tank space E3, the electrolytic solution supply unit 18 supplies the plating solution toward the center of the upper surface portion 25a, thereby diffusing the plating solution radially from the center of the upper surface portion 25a.

[0035] 10 , the electrolytic solution supply unit 18 has a shape in which the supply port side end of the plating solution supply pipe 61 is bent from the horizontal direction to the vertical direction upward. Furthermore, the supply port side end of the plating solution supply pipe 61 is provided with a plurality of branch pipes 63, and the plurality of branch pipes 63 are arranged to extend radially from the supply port side end of the plating solution supply pipe 61 as a center. Therefore, the supply ports 62 of the plurality of branch pipes 63 are arranged in a row in the circumferential direction. The electrolytic solution supply unit 18 supplies the plating solution from the plurality of branch pipes 63 in the inner lower tank space E3, thereby diffusing the plating solution radially.

[0036] 11, the electrolytic solution supply unit 18 has a shape in which the supply port side end of the plating solution supply pipe 61 is bent from the horizontal direction to the vertical direction, and the opening of the supply port 62 has a tapered shape that widens from the bottom to the top. The electrolytic solution supply unit 18 supplies the plating solution toward the center of the upper surface portion 25a in the inner lower tank space E3, thereby diffusing the plating solution radially from the center of the upper surface portion 25a.

[0037] Next, the electrolyte solution discharge unit 19 will be described with reference to FIG. 1. The electrolyte solution discharge unit 19 discharges the plating solution from the electrolyte solution tank 10. The electrolyte solution discharge unit 19 has a discharge pipe 64 and a pump 65 installed in the discharge pipe 64. The discharge pipe 64 is disposed in the inner upper tank space E1. When the pump 65 is operated, the electrolyte solution discharge unit 19 discharges the plating solution in the inner upper tank space E1 through the discharge pipe 64. The plating solution discharged by the electrolyte solution discharge unit 19 is supplied from the electrolyte solution supply unit 18 after undergoing reprocessing such as foreign matter removal.

[0038] When electroplating a conductive workpiece W in a film forming apparatus 1 as shown in FIG. 1 , the film forming apparatus 1 rotates the conductive workpiece W attached to the rotary shaft 21 and charges the plating metal 13 as an anode and the conductive workpiece W as a cathode. The film forming apparatus 1 also supplies air bubbles from an air supply unit 17 and a plating solution from an electrolyte supply unit 18. The plating solution supplied from the electrolyte supply unit 18 flows from the inner lower tank space E3 toward the surface of the conductive workpiece W through the plating solution passing holes 42 in the workpiece-side shielding plate 15. Some of the air bubbles supplied from the air supply unit 17 accumulate in the air reservoir 25b in the workpiece-side shielding plate 15, while the other part of the air bubbles flows toward the surface of the conductive workpiece W through the plating solution passing holes 42 together with the plating solution.

[0039] A portion of the plating solution that has passed through the surface of the conductive workpiece W flows from the lower shielding plate 25 toward the upper shielding plate 24 and flows into the inner upper tank space E1 through the plating solution passage holes 32 of the upper shielding plate 24. Thereafter, the film forming device 1 discharges the plating solution that has flowed into the inner upper tank space E1 through the electrolyte discharge part 19.

[0040] At this time, the current flowing through the plating solution is blocked in the inner upper tank space E1 and the inner lower tank space E3, so the formation of plating is suppressed at the upper and lower ends of the conductive workpiece W.

[0041] In this embodiment, the conductive workpiece W is configured to rotate, but the conductive workpiece W may be stationary, and there is no particular limitation as long as a coating can be suitably formed.

[0042] As described above, the film forming apparatus 1 according to this embodiment can be understood, for example, as follows.

[0043] The film forming apparatus 1 according to the first aspect forms a film on a conductive workpiece W using an electrolytic solution (plating solution), and includes an electrolytic solution tank 10 for storing the electrolytic solution, a workpiece support 11 for supporting the conductive workpiece W immersed in the electrolytic solution, an insulating workpiece-side shielding plate 15 attached to the conductive workpiece W, and an insulating tank-side shielding plate 16 provided at the bottom of the electrolytic solution tank 10 and arranged opposite the workpiece-side shielding plate 15 in the vertical direction, and the workpiece-side shielding plate 15 faces the tank-side shielding plate 16. The tank side shielding plate 15 has an air reservoir 25b provided in a lower portion thereof for storing air, and the tank side shielding plate 16 is provided so as to protrude upward from the liquid surface of the electrolyte formed in the air reservoir 25b, thereby separating an inner lower tank space E3 facing the conductive workpiece W in the vertical direction from an outer lower tank space E4 located outside the inner lower tank space E3, and the workpiece side shielding plate 15 further has an electrolyte passage hole (plating solution passage hole 42) that allows the electrolyte in the inner lower tank space E3 to flow toward the conductive workpiece W.

[0044] This configuration can interrupt the current flowing through the plating solution in the inner lower tank space E3, thereby preventing excessive deposition of metal on the lower end of the conductive workpiece W. This allows for favorable film formation on the conductive workpiece W while preventing plating defects.

[0045] In a second aspect, in the film forming apparatus 1 according to the first aspect, the upper portion of the work side shielding plate 15 is arranged to protrude from the liquid surface of the electrolyte in the electrolyte tank 10, thereby dividing the space into an inner upper tank space E1 facing the conductive work W in the vertical direction and an outer upper tank space E2 located outside the inner upper tank space E1.

[0046] This configuration can interrupt the current flowing through the plating solution in the inner upper tank space E1, thereby suppressing excessive deposition of metal on the upper end of the conductive workpiece W. This allows for more optimal film formation on the conductive workpiece W while further suppressing the occurrence of plating defects.

[0047] As a third aspect, the film forming apparatus 1 according to the second aspect further includes an electrolyte discharge part 19 that discharges the electrolyte from the inner upper tank space E1.

[0048] According to this configuration, the plating solution remaining in the inner upper tank space E1 can be discharged. Furthermore, by discharging the plating solution from the inner upper tank space E1, the plating solution can be made to flow toward the inner upper tank space E1, so that the plating solution can be suitably circulated above the surface of the conductive workpiece W.

[0049] As a fourth aspect, in the film forming apparatus 1 relating to any one of the first to third aspects, the work side shielding plate 15 has an upper shielding plate 24 arranged on the upper side of the conductive work W and a lower shielding plate 25 arranged on the lower side of the conductive work W.

[0050] According to this configuration, the work-side shielding plate 15 can be made into a structure divided into two parts, upper and lower, making it easier to attach the work-side shielding plate 15 to the conductive work W.

[0051] As a fifth aspect, in the film forming apparatus 1 relating to the fourth aspect, the lower shielding plate 25 has an upper surface portion 25a that faces the lower end surface of the conductive workpiece W and is the part that is attached to the conductive workpiece W, the air reservoir portion 25b that is provided on the periphery of the upper surface portion 25a, and a protrusion portion 25c that protrudes from the upper surface portion 25a and is provided opposite the outer peripheral surface of the lower side of the conductive workpiece W.

[0052] With this configuration, the protrusion 25c can block the current flowing toward the lower end of the conductive workpiece W, thereby suppressing current concentration at the lower end of the conductive workpiece W and further suppressing excessive metal deposition at the lower end of the conductive workpiece W.

[0053] As a sixth aspect, in the film forming apparatus 1 relating to any one of the first to fifth aspects, the air reservoir portion 25b includes an air inner wall 45 located in the inner lower tank space E3, sandwiched between the tank side shielding plate 16, and an air outer wall 46 located in the outer lower tank space E4, sandwiched between the tank side shielding plate 16, and the lower end of the air outer wall 46 is located above the lower end of the air inner wall 45.

[0054] According to this configuration, the air accumulated in the air reservoir 25b can be released to the outer lower tank space E4 instead of the inner lower tank space E3, which prevents large air bubbles from moving toward the surface of the conductive workpiece W via the inner lower tank space E3.

[0055] As a seventh aspect, in the film forming apparatus 1 relating to any one of the first to sixth aspects, the air reservoir portion 25b includes an air inner wall 45 located in the inner lower tank space E3, sandwiched between the tank side shielding plate 16, an air outer wall 46 located in the outer lower tank space E4, sandwiched between the tank side shielding plate 16, and an air vent hole 57 formed through the air outer wall 46.

[0056] According to this configuration, the air accumulated in the air reservoir 25b can be released to the outer lower tank space E4 instead of the inner lower tank space E3, which prevents large air bubbles from moving toward the surface of the conductive workpiece W via the inner lower tank space E3.

[0057] In an eighth aspect, the film forming apparatus 1 relating to any one of the first to seventh aspects further includes an air supply unit 17 provided below the tank side shielding plate 16 and supplying air bubbles, and the air supply unit 17 supplies air bubbles toward the inner lower tank space E3 and the outer lower tank space E4.

[0058] This configuration allows air bubbles to be supplied not only to the inner lower tank space E3 but also to the outer lower tank space E4, thereby allowing foreign matter adhering to the surface of the plating metal 13 or the like in the electrolyte tank 10 to be removed by the air bubbles.

[0059] As a ninth aspect, in the film forming apparatus 1 according to the eighth aspect, the air supply section 17 has a plurality of blow-out holes 71 for supplying air bubbles toward the inner lower tank space E3, and the plurality of blow-out holes 71 are provided in greater numbers at positions facing the air reservoir section 25b than at positions not facing the air reservoir section 25b.

[0060] According to this configuration, the air bubbles can be supplied to the appropriate location, and therefore the air bubbles can be prevented from accumulating and forming large bubbles.

[0061] In a tenth aspect, the film forming apparatus 1 according to any one of the first to ninth aspects further includes an electrolyte supply unit 18 that supplies the electrolyte to the inner lower tank space E3, and the electrolyte supply unit 18 supplies the electrolyte to the inner lower tank space E3 in a dispersed manner.

[0062] This configuration can prevent uneven flow of the plating solution supplied to the inner lower tank space E3, thereby enabling film formation to be carried out in an optimal manner. [Explanation of symbols]

[0063] 1. Film forming device 10 Electrolyte tank 11 Work support part 13 Plated metals 15 Work side shielding plate 16 Tank side shielding plate 17 Air supply unit 18 Electrolyte supply section 19 Electrolyte drain 24 Upper shielding plate 25, 55, 56, 58 Lower shielding plate 25a Top part 25b Air reservoir 25c protrusion 31 Mounting hole 32 Plating solution passage hole in upper shielding plate 42 Plating solution passage hole in lower shielding plate 45 Air Inner Wall 46 Air Exterior Wall 57 Air vent hole 61 Plating solution supply pipe 62 Supply port 63 Branch Pipe 64 Discharge pipe 65 Pump 71 Blowout hole W Conductive workpiece E1 Inner upper tank space E2 Upper outer tank space E3 Inner lower tank space E4 Lower outer tank space

Claims

1. A film forming device for forming a film on a conductive workpiece using an electrolyte, an electrolyte tank for storing the electrolyte; a work support portion for supporting the conductive workpiece immersed in the electrolytic solution; an insulating work-side shielding plate attached to the conductive work; An insulating tank-side shielding plate is provided at the bottom of the electrolytic solution tank and is arranged opposite the work-side shielding plate in the vertical direction, The workpiece side shielding plate is An air reservoir portion is provided in a lower portion facing the tank-side shielding plate and configured to store air, The tank side shielding plate is The air reservoir is provided so as to protrude upward from the liquid surface of the electrolytic solution formed in the air reservoir, thereby dividing an inner lower tank space facing the conductive workpiece in the vertical direction and an outer lower tank space located outside the inner lower tank space, The workpiece side shielding plate is The film forming device further has an electrolyte passage hole that allows the electrolyte in the inner lower tank space to flow toward the conductive workpiece.

2. The film forming apparatus of claim 1, wherein the upper portion of the work-side shielding plate is arranged to protrude from the liquid surface of the electrolyte in the electrolyte tank, thereby dividing an inner upper tank space facing the conductive work in the vertical direction and an outer upper tank space located outside the inner upper tank space.

3. The film forming apparatus according to claim 2 , further comprising an electrolyte discharge section that discharges the electrolyte from the inner upper tank space.

4. The film forming apparatus according to claim 1 , wherein the work-side shielding plate comprises an upper shielding plate disposed above the conductive workpiece and a lower shielding plate disposed below the conductive workpiece.

5. The lower shielding plate is An upper surface portion that faces the lower end surface of the conductive workpiece and is a portion that is attached to the conductive workpiece; the air reservoir provided on the periphery of the upper surface portion; 5. The film forming apparatus according to claim 4, further comprising a protrusion provided to protrude from the upper surface portion and facing the outer peripheral surface of the lower side of the conductive workpiece.

6. The air reservoir portion is an air inner wall located in the inner lower tank space across the tank side shielding plate; an air outer wall located in the outer lower tank space across the tank side shielding plate, 2. The film forming apparatus according to claim 1, wherein a lower end of the outer air wall is positioned above a lower end of the inner air wall.

7. The air reservoir portion is an air inner wall located in the inner lower tank space across the tank side shielding plate; an air outer wall located in the outer lower tank space across the tank side shielding plate; The film forming apparatus according to claim 1 , further comprising an air vent hole formed through the outer wall.

8. Further provided is an air supply unit provided below the tank side shielding plate and supplying air bubbles, The film forming apparatus according to claim 1 , wherein the air supply unit supplies air bubbles toward the inner lower tank space and the outer lower tank space.

9. the air supply unit has a plurality of blow-out holes for supplying air bubbles toward the inner lower tank space, The film forming apparatus according to claim 8 , wherein the number of the blowout holes is greater at a position facing the air reservoir than at a position not facing the air reservoir.

10. The electrolytic solution supply unit supplies the electrolytic solution to the inner lower tank space. The film forming apparatus according to claim 1 , wherein the electrolytic solution supply unit supplies the electrolytic solution to the inner lower tank space in a dispersed manner.

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