Plating device and plating method

Abstract

To provide a technique for subjecting an upper face of a substrate supported in a face-up state to plating treatment, which prevents quality deterioration of a plating film due to an anode slime without using a special anode material.SOLUTION: A plating apparatus plates at least one main surface of a rectangular substrate, wherein an anode electrode arranged above the substrate is separated from a plating liquid in a treatment tank by a separation tank. The bottom part of the separation part is composed of an electrolytic diaphragm, and an anode electrode is immersed in the liquid therein. An anode slime generated from the anode electrode is shielded by the electrolytic diaphragm, and is not attached to the substrate. By providing a mechanism for inclining the separation tank, the liquid in the separation tank can be efficiently discharged, and accumulation of anode slime on the electrolytic diaphragm is prevented.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a plating apparatus and a plating method for plating at least one main surface of a rectangular substrate such as a printed wiring board or a glass substrate. [Background technology]

[0002] A technology for forming a thin metal film by plating on the surface of various substrates such as semiconductor substrates, printed wiring substrates, glass substrates, etc. For example, in the plating apparatus described in Patent Document 1, the substrate to be plated is held in a horizontal position with its face up, and an anode electrode is placed above the substrate immersed in a plating solution. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-129286 A Summary of the Invention [Problem to be solved by the invention]

[0004] For example, when a metal material is used as the anode electrode, as in the case of electrolytic copper plating, the metal material dissolves into the plating solution as the process proceeds. It is known that at this time, a residue (also called anode slime) is generated that does not electrochemically dissolve in the solution and is liberated from the anode electrode. In the conventional technology described in Patent Document 1, the residue liberated from the anode electrode settles in the plating solution and adheres to the upper surface of the substrate supported face-up downward. This can cause a deterioration in the quality of the plating film.

[0005] To address this issue, technologies that have been put into practical use include adding chemical substances to the metallic material that is the anode electrode material to suppress the formation of anode slime, and using an insoluble anode and supplying metal ions, which are the material for the plating film, from the outside as salt.

[0006] However, these techniques require the use of special materials as anodes or the preparation of separate chemical substances that serve as metal ion sources, and there is a possibility that substances that are not necessary for the original electrochemical reaction may be mixed into the plating film and degrade its quality. For these reasons, a technology is needed that can prevent the deterioration of the plating film quality caused by the influence of anode slime, without using special anode materials or metal salts.

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a technology for performing plating processing on the upper surface of a substrate supported in a face-up state, which can prevent deterioration of the quality of the plating film due to anode slime without using a special anode material. [Means for solving the problem]

[0008] One aspect of the present invention is a plating apparatus for plating at least one main surface of a flat substrate, the plating apparatus including a treatment tank for storing a plating solution, a holding unit for holding the substrate in a horizontal position with the main surface facing upward within the treatment tank, a cathode electrode in contact with a portion of the main surface of the substrate held by the holding unit, an anode electrode disposed above the substrate held by the holding unit and facing the main surface, a power supply unit connected to the anode electrode and the cathode electrode, and an isolation unit for isolating the anode electrode from the plating solution within the treatment tank by surrounding the sides and below of the anode electrode.

[0009] Here, the isolation unit includes a box-shaped isolation tank having at least a bottom formed of an electrolytic diaphragm and accommodating the anode electrode in an internal space, a tilting mechanism that switches the attitude of the isolation tank between a horizontal attitude in which the bottom is horizontal and an inclined attitude in which the bottom is inclined with respect to a horizontal plane, a supply unit that supplies liquid into the internal space to immerse the anode electrode in the liquid, and a discharge unit that discharges the liquid from the isolation tank in the inclined attitude.

[0010] Another aspect of the present invention is a plating method for plating at least one main surface of a flat substrate, the plating method comprising the steps of: holding the substrate in a horizontal position with the one main surface facing upward in a treatment tank that stores a plating solution; bringing a cathode electrode into contact with a part of the one main surface of the substrate held by the holder; and disposing an anode electrode above the substrate so as to face the one main surface; and applying a voltage between the anode electrode and the cathode electrode.

[0011] Here, the anode electrode is isolated from the plating solution by being surrounded laterally and downwardly by an isolation tank having at least a bottom made of an electrolytic diaphragm, and the voltage is applied while the anode electrode is immersed in the liquid stored in the isolation tank. After the voltage application is completed, the attitude of the isolation tank is changed from a horizontal attitude to an inclined attitude, and the liquid is discharged from a position on the side wall of the isolation tank that is the lowest in the vertical direction in the inclined attitude.

[0012] In the invention thus configured, the anode electrode is disposed above the substrate, which is held in the plating solution with the surface to be plated facing upward, and the anode electrode and the substrate are separated by an electrolytic diaphragm. Therefore, a current flows between the anode electrode and the substrate via the electrolytic diaphragm, which causes the plating reaction to proceed, while the insoluble components liberated from the anode electrode are separated by the electrolytic diaphragm and prevented from adhering to the substrate.

[0013] Here, as plating processes are repeated, non-soluble components accumulate at the bottom of the isolation tank. To prevent this, the liquid in the isolation tank needs to be periodically drained and refreshed. However, the bottom side of the isolation tank faces the substrate, and it is difficult to secure sufficient space to place a structure for draining the liquid. Furthermore, draining the liquid to the side of the isolation tank does not efficiently drain the liquid remaining near the bottom of the isolation tank.

[0014] Therefore, in the present invention, the isolation tank is made switchable between a horizontal position and an inclined position, and the liquid is discharged when the isolation tank is in the inclined position, so that the liquid can be efficiently discharged from the side of the isolation tank. As a result, in the present invention, it is possible to perform plating processing without allowing anode slime generated from the anode electrode arranged above to adhere to the substrate. By periodically refreshing the liquid, it is possible to suppress the accumulation of anode slime on the electrolytic diaphragm, and stable processing over the long term is possible, especially when processing a large number of substrates continuously. Effect of the Invention

[0015] As described above, in the present invention, the anode electrode is disposed above the substrate supported in a horizontal position, and the anode slime released from the anode electrode is blocked by the electrolytic diaphragm and does not adhere to the substrate. This prevents the anode slime from adhering to the upper surface of the substrate and degrading the quality of the plating film. In addition, by tilting the isolation tank to efficiently drain the liquid, the liquid is refreshed and the accumulation of the anode slime on the electrolytic diaphragm is suppressed, allowing the plating process to be performed stably over the long term. [Brief description of the drawings]

[0016] [Figure 1] 1 is a diagram showing a schematic configuration of an embodiment of a plating apparatus according to the present invention; [Diagram 2] FIG. 2 is a diagram showing a schematic configuration of a plating processing section. [Diagram 3] FIG. 2 is a diagram showing a schematic configuration of a plating processing section. [Figure 4] FIG. 2 is a diagram showing a schematic configuration of a chuck mechanism. [Diagram 5] FIG. 2 is a diagram showing a schematic configuration of a main part of an anode electrode unit. [Figure 6] FIG. 2 is a diagram showing a schematic diagram of an isolation tank immersed in a plating tank. [Figure 7] FIG. 4 is an external perspective view showing a support mechanism for a separator in the anode electrode unit. [Figure 8]FIG. 2 is a diagram showing a schematic diagram of supply and discharge of plating solution to and from an isolation tank. [Figure 9] 11A and 11B are diagrams illustrating the raising and lowering operation of the isolation tank in more detail. [Figure 10] 11A and 11B are diagrams illustrating the lifting and lowering operation of the isolation tank in more detail. [Figure 11] 11A and 11B are diagrams illustrating the raising and lowering operation of the isolation tank in more detail. [Figure 12] 11A and 11B are diagrams illustrating the lifting and lowering operation of the entire support mechanism. [Figure 13] FIG. 2 is a block diagram showing the electrical configuration of the plating apparatus. [Figure 14] 1 is a flowchart showing a plating process. [Figure 15] FIG. 2 is a diagram showing a schematic operation of each unit. [Figure 16] FIG. 13 is a diagram showing a modified example of the anode electrode. [Figure 17] 13A and 13B are diagrams illustrating a modified example of the support mechanism in the anode electrode unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, specific aspects of the plating apparatus according to the present invention will be described with reference to specific embodiments.

[0018] FIG. 1 is a diagram showing a schematic configuration of one embodiment of a plating apparatus according to the present invention. This plating apparatus 1 is an apparatus for forming a metal (e.g., gold) film by electrolytic plating on at least one main surface of various substrates S (hereinafter simply referred to as "substrate") such as semiconductor substrates, printed wiring substrates, and glass substrates. For the following explanation, an XYZ Cartesian coordinate system is defined as shown in FIG. 1. FIG. 1 is a diagram showing a side view of the plating apparatus 1, in which the horizontal direction and perpendicular to the paper surface of FIG. 1 is defined as the X direction, and the horizontal direction perpendicular to the X direction and along the paper surface of FIG. 1 is defined as the Y direction. The vertical direction is defined as the Z direction. In each diagram, the dotted arrows indicate the movement directions of each member.

[0019] The plating apparatus 1 has a configuration in which each part described below is assembled in a housing 10 formed by combining multiple frame members. In Fig. 1 and the following figures, in order to avoid cluttering the drawings, some components may be omitted as appropriate. Specifically, components such as a holding mechanism for holding components, a cover for covering the components, and a mechanism for attaching them to the housing 10 may be omitted from illustration because they contribute relatively little to the establishment of the invention and because appropriate publicly known technology can be applied to their structures and therefore no special explanation is considered to be required.

[0020] FIG. 1 is a front view of a plating apparatus 1. The plating apparatus 1 is provided with a transport section 2 that transports a substrate S along the Y direction. The transport section 2 includes a plurality of transport rollers 21 arranged along the Y direction. The transport rollers 21 are each supported by a support mechanism (not shown) so as to be rotatable about the X direction as their axial direction. The transport rollers 21 are rotated by a drive mechanism (not shown) so that the transport section 2 transports the substrate S in the Y direction in a horizontal position. The rectangular substrate S is transported with one of the four peripheral sides at the front. In the following, the transport path of the substrate S is represented by the symbol P, and the transport direction is represented by the symbol Dt.

[0021] The plating apparatus 1 further includes a carry-in section 3, a plating processing section 4, a rinsing processing section 5, an unloading section 6, a power supply section 7, and a control section 9. The carry-in section 3, the plating processing section 4, the rinsing processing section 5, and the unloading section 6 are arranged in this order along the transport direction Dt (Y direction) of the substrate by the transport section 2. That is, in this plating apparatus 1, the substrate S is subjected to necessary processing in each of the above-mentioned processing sections while being transported in the Y direction by the transport section 2.

[0022] The loading section 3 receives and temporarily holds the unprocessed substrate S transported from the outside, and supplies the substrate S to the plating section 4 at the required timing. The plating section 4 is the processing main body that executes the plating method according to the present invention, and performs plating by immersing the substrate S in a plating solution. The configuration and operation of the plating section 4 will be described in detail later.

[0023] The rinsing processing unit 5 includes a rinsing tank 51, a tray 52, and a rinsing liquid supply / discharge unit 59. The rinsing tank 51 is capable of storing a rinsing liquid in an internal space having a size sufficient to accommodate the substrate S. An opening is provided on the Y-direction side surface of the rinsing tank 51 at a portion overlapping the transport path P, and shutters 51a, 51b are provided for the opening in a manner that allows it to be opened and closed freely.

[0024] The tray 52 is disposed below the rinsing tank 51 and receives the rinsing liquid spilled from the rinsing tank 51. The rinsing liquid supply / discharge unit 59 supplies the rinsing liquid to the rinsing tank 51 and discharges the rinsing liquid from the rinsing tank 51 as necessary. The rinsing processing unit 5 performs a rinsing process on the substrate S immersed in the plating liquid in the plating processing unit 4. Water, for example, is used as the rinsing liquid. The unloading unit 6 temporarily holds the substrate S after the rinsing process until it is removed to a post-processing step by an external transport device.

[0025] The power supply unit 7 supplies the necessary power to each part of the apparatus. The control unit 9 controls each part of the apparatus configured as described above, and causes the plating apparatus 1 to perform a predetermined process. The hardware configuration of the control unit 9 may be the same as that of a general computer device. That is, the CPU (FIG. 9) provided in the control unit 9 executes a control program prepared in advance to realize various processes described below. Although not specifically described below, each part of the apparatus operates based on a control command from the control unit 9.

[0026] The plating processing section 4 includes a plating tank 41, vats 42 and 44, a chuck section 40, a moving mechanism 43, an anode electrode unit 45, a cleaning mechanism 48, and a plating liquid supply / discharge section 49. The plating tank 41 is capable of storing plating liquid in an internal space having a size sufficient to accommodate the substrate S. The vat 42 is disposed below the plating tank 41 and receives spilled plating liquid. The chuck section 40 is disposed above the plating tank 41 and holds the substrate S to be plated. The vat 44 is disposed adjacent to the vat 42 below the plating tank 41 on the (-Y) side. The cleaning mechanism 48 cleans the chuck section 40 with an appropriate cleaning liquid (e.g., water). For this purpose, the cleaning mechanism 48 includes a cleaning nozzle 481 (FIG. 2) provided in the vat 44 and a cleaning liquid supply / discharge section 482 that supplies cleaning liquid to the cleaning nozzle 481. The plating solution supply / discharge section 49 supplies plating solution to the plating tank 41 and discharges plating solution from the plating tank 41 as required.

[0027] Figures 2 and 3 are diagrams showing a schematic configuration of the plating processing section. More specifically, Figure 2 is a front view of the main parts of the plating processing section 4 as seen in the (-X) direction, and Figures 3(a) and 3(b) are side views of the plating processing section 4 as seen in the (+Y) direction. In order to avoid complicating the drawings, the anode electrode unit 45 is omitted from Figures 2 and 3(a).

[0028] 1 and 2, openings are provided on the (-Y) side surface and the (+Y) side surface of plating tank 41 at portions overlapping with transport path P, and shutters 41a, 41b that can be opened and closed are provided at the openings. When shutters 41a, 41b are in an open state, substrate S transported along transport path P by transport unit 2 can pass through the openings provided on the sides of plating tank 41. This allows unprocessed substrate S to be carried into plating tank 41 and processed substrate S to be carried out of plating tank 41.

[0029] On the other hand, in the closed state, the opening provided on the side of the plating tank 41 is closed. At this time, the transport path P of the substrate S is blocked, but the plating solution can be stored inside the plating tank 41 beyond the height of the opening. After the substrate S is accommodated in the plating tank 41 with the (-Y) side shutter 41a open, the shutter 41a is closed and the internal space of the plating tank 41 is filled with the plating solution L, so that the substrate S is immersed in the plating solution L and plated. After that, when the plating solution is discharged and the (+Y) side shutter 41b is opened, the liquid level of the plating solution L drops to below the lower end of the opening, and the substrate S after plating is transported to the rinsing section 5. The shutters 41a and 41b may be opened and closed independently of each other, or may be opened and closed integrally.

[0030] 3(a), a rotary motor 23 is coupled to a rotary shaft 22 of the transport roller 21. The rotary motor 23 rotates in response to a control command from the control unit 9, thereby rotating the transport roller 21, thereby transporting the substrate S in the Y direction. Note that some of the rollers may be driven rollers that are not connected to a drive source.

[0031] As shown in Fig. 3(a), two sets of chuck parts 40 are arranged corresponding to both ends in the X direction of the substrate S accommodated in the plating tank 41. Only one set on the (+X) side is shown in Figs. 1 and 2. The two sets of chuck parts 40 are arranged symmetrically with respect to the YZ plane, but have the same basic structure. That is, each chuck part 40 includes at least one chuck mechanism 400, a support frame 430 that supports the chuck mechanism 400, and a movement mechanism 43 that moves the support frame 430 in the Y direction.

[0032] The support frame 430 is supported movably in the Y direction by a moving mechanism 43 attached to the upper frame 11 among the frame members constituting the housing 10. More specifically, the moving mechanism 43 includes a guide rail 431 fixed to the upper frame 11 above the plating processing section 4 and extending in the Y direction, a slider 432 engaged with the guide rail 431, and a driving source (not shown) for moving the slider 432 in the Y direction along the guide rail 431. As these configurations, an appropriate linear motion mechanism, for example, a linear motor, a linear motion guide mechanism, a chain drive mechanism, a belt drive mechanism, or the like, can be applied. For example, a single-axis robot in which such a drive mechanism is integrated in advance can be suitably applied.

[0033] A support frame 430 is coupled to the lower end of the slider 432, and the chuck mechanism 400 is fixed to the support frame 430. Therefore, when the slider 432 moves in the Y direction along the guide rail 431, the support frame 430 and the chuck mechanism 400 attached thereto move integrally in the Y direction. In other words, the moving mechanism 43 operates in response to a control command from the control unit 9 to move the slider 432, thereby moving the chuck mechanism 400 in the Y direction.

[0034] In this embodiment, three sets of chuck mechanisms 400 are attached to one support frame 430 in a line in the Y direction, and they move together in the Y direction as the support frame 430 moves. This allows each chuck mechanism 400 to move back and forth in the Y direction between a "plating position" P1 located above the plating tank 41 and a "cleaning position" P2 located above the vat 44. In FIG. 2, the chuck mechanism 400 at the plating position P1 is shown by a solid line, and the chuck mechanism 400 at the cleaning position P2 is shown by a dotted line. Meanwhile, in FIG. 1, the chuck mechanism 400 at the cleaning position P2 is shown by a solid line.

[0035] The chuck mechanism 400 grips the substrate S to stably maintain the position of the substrate S in the plating tank 41, and brings a built-in cathode electrode into electrical contact with one main surface of the substrate S. A DC voltage is then applied between an anode electrode and a cathode electrode, which will be described later, to form a coating on the one main surface by electrolytic plating. In this case, it is assumed that the coating is formed on the upper surface of the substrate S.

[0036] The chuck mechanisms 400 grip the substrate S at both ends in the X direction, i.e., at both ends in the width direction perpendicular to the transport direction Dt. A large portion of the substrate S at both ends in the X direction is gripped by a plurality of chuck mechanisms 400 provided along the Y direction, i.e., the transport direction Dt of the substrate S. The chuck mechanisms 400 grip the substrate S to stably maintain its position, and can apply a uniform potential over a wide range by contacting the cathode electrode 412 extending in the Y direction with the substrate S. This allows the plating apparatus 1 to form a plating film with good uniformity on the substrate S.

[0037] FIG. 4 is a diagram showing a schematic configuration of the chuck mechanism. More specifically, FIG. 4(a) is a perspective view showing a schematic configuration of the chuck mechanism 400, and FIG. 4(b) is a diagram showing a state in which the chuck mechanism 400 holds the substrate S. In the following, when explaining the structure and operation of the chuck mechanism 400, the chuck mechanism 400 that holds the (-X) side end of the substrate S is mainly illustrated as an example, but the structure and operation of the chuck mechanism that holds the (+X) side end of the substrate S can be understood by considering the same structure inverted around the Z axis. In addition, in order to improve the visibility of the figure, part of the configuration of the chuck mechanism 400 is omitted in FIG. 4(a).

[0038] The chuck mechanism 400 grips the X-direction end of the substrate S with an upper chuck 411 and a lower chuck 421 that can be raised and lowered independently of each other. Specifically, the upper chuck 411 and the lower chuck 421 are each a long and thin flat member extending with the Y direction as the longitudinal direction, and grip the substrate S by a bottom surface 411b of the upper chuck 411 abutting against the (-X) side end of the upper surface Sa of the substrate S and an top surface 421a of the lower chuck 421 abutting against the (-X) side end of the lower surface Sb of the substrate S. In practice, a cathode electrode 412 is attached to the bottom surface 411b of the upper chuck 411, and the cathode electrode 412 comes into contact with the upper surface Sa of the substrate S.

[0039] The cathode electrode 412 is electrically connected to the power supply unit 7. In addition, a sealing member 415 formed in a ring shape from an elastic material is provided so as to surround the periphery of the cathode electrode 412. When the upper chuck 411 is separated from the substrate S, the lower end of the sealing member 415 extends below the lower surface of the cathode electrode 412.

[0040] 4(b), when the cathode electrode 412 comes into contact with the upper surface Sa of the substrate S, the seal member 415 elastically deforms to surround the cathode electrode 412 in an airtight state. Therefore, even when the substrate S is immersed in the plating solution, the cathode electrode 412 is maintained in a dry state without coming into contact with the plating solution. This makes it possible to prevent corrosion of the cathode electrode 412 or formation of a coating due to contact with the plating solution.

[0041] 4(b), the lower chuck 421 abuts against the lower surface Sb of the substrate S from below, thereby acting to determine the position of the substrate S in the height direction (Z direction). The lower chuck 421 also acts as a backup when the cathode electrode 412 provided on the upper chuck 411 is brought into contact with the substrate S. This ensures that the height position of the substrate S is stably maintained, and also ensures reliable electrical contact between the cathode electrode 412 and the substrate upper surface Sa.

[0042] A shaft member 413 extending in the Z direction is attached to an upper surface 411a of the upper chuck 411, and the shaft member 413 is supported by a lifting mechanism 414 so as to be movable up and down. The upper chuck 411 is fixed to the shaft member 413 by using a screw, for example, and is detachable (i.e. replaceable). The lifting mechanism 414 has an appropriate linear motion mechanism such as a solenoid, a linear motor, or a ball screw mechanism, and lifts and lowers the shaft member 413. This causes the upper chuck 411 attached to the lower end of the shaft member 413 to lift and lower. Here, a unit integrally formed including the upper chuck 411, the shaft member 413, the lifting mechanism 414, etc. is referred to as an "upper chuck unit 410."

[0043] Similarly, a shaft member 423 extending in the Z direction is attached to an upper surface 421a of the lower chuck 421, and the shaft member 423 is supported by a lifting mechanism 424 so as to be movable up and down. The lower chuck 421 is fixed to the shaft member 423 by using a screw, for example, and is detachable. The lifting mechanism 424 has an appropriate linear motion mechanism, for example, a solenoid, a linear motor, or a ball screw mechanism, and lifts and lowers the shaft member 423. This causes the lower chuck 421 attached to the lower end of the shaft member 423 to lift and lower. Here, a unit integrally formed including the lower chuck 421, the shaft member 423, the lifting mechanism 424, etc. is referred to as a "lower chuck unit 420."

[0044] The upper chuck unit 410 is fixed to a support member 401. Therefore, the upper chuck 411 can only move up and down relative to the support member 401. On the other hand, the lower chuck unit 420 is attached to the support member 401 via an advance / retract mechanism 402. Specifically, the support member 403 to which the lower chuck unit 420 is attached is connected to a movable part of the advance / retract mechanism 402 whose movable direction is the X direction. The advance / retract mechanism 402 has an appropriate linear motion mechanism such as a solenoid, an air cylinder, a linear motor, or a ball screw mechanism, and its main body is fixed to the support member 401.

[0045] Therefore, the lower chuck unit 420 can move in the X direction within a movable range defined by a stopper (not shown) by operation of the advancing / retreating mechanism 402. Therefore, the lower chuck 421 can move up and down relative to the support member 401 by operation of the lifting mechanism 424, and can move forward and backward in the X direction by the advancing / retreating mechanism 402 moving the lifting mechanism 424.

[0046] When the lower chuck 421 advances to the furthest position on the (+X) side within its movable range, as shown by the solid line in Fig. 4(b), the (+X) side tip of the lower chuck 421 is located on the (+X) side of the edge face of the substrate S, and the upper surface 421a of the lower chuck 421 can support the lower surface Sb of the substrate S. On the other hand, as shown by the dotted line in Fig. 4(b), when the lower chuck 421 retreats to the furthest position on the (-X) side within its movable range, the (+X) side tip of the lower chuck 421 retreats to the (-X) side of the edge face of the substrate S. This prevents the lower chuck 421 from coming into contact with the substrate S when it moves up and down.

[0047] In the chuck mechanism 400, the upper chuck 411 and the lower chuck 421 cooperate to grip the substrate S in the plating tank 41. Specifically, the upper chuck 411 and the lower chuck 421 are lowered from the chuck mechanism 400 positioned at the plating position into the plating tank 41 and grip the edge of the substrate S at the same height as the substrate S supported by the transport rollers 21. Therefore, the substrate S is held in the plating tank 41 in a horizontal position with its upper surface flat. The Z direction positions of the upper chuck 411 and the lower chuck 421 at this time will be referred to as the "lower position" hereinafter.

[0048] As shown in Fig. 1 and Fig. 3(b), an anode electrode unit 45 is disposed above the transport path P in the plating tank 41. The anode electrode unit 45 is divided into a plurality of plate-shaped members and includes a plurality of anode electrodes 451, each of which is electrically connected to the power supply unit 7. The anode electrodes 451 are contained in a box-shaped isolation tank 450 with an open top.

[0049] Fig. 5 is a diagram showing a schematic configuration of the main part of the anode electrode unit. The anode electrode 451 has a plurality of electrode plates arranged in a horizontal direction. In the example shown in Fig. 5(a), nine electrode plates 451a to 451i arranged in a 3 x 3 matrix form the anode electrode 451. The lower surfaces of the electrode plates 451a to 451i facing the substrate S are mutually in the same horizontal plane.

[0050] The anode electrode 451 is electrically connected to the power supply unit 7 and receives a supply of electric energy. More specifically, the power supply unit 7 has a plurality of output units 71a-71i that can set output currents independently of one another, and the plurality of electrode plates and the plurality of output units are electrically connected one-to-one, such that the output unit 71a is connected to the electrode plate 451a, and the main power unit 71b is connected to the electrode plate 451b. Each of the output units 71a-71i can be configured, for example, by a DC constant current source, or a DC or pulsating voltage source that can set an upper limit of the output current.

[0051] The output current of each of the output units 71a-71i is determined in response to a control command from the control unit 9. Specifically, the power supply unit 7 is provided with a setting storage unit 72, which stores information related to the current value to be output by each of the output units 71a-71i. Each of the output units 71a-71i outputs a current having a predetermined current value based on the information stored in the setting storage unit 72. The current value of each of the output units 71a-71i stored and saved in the setting storage unit 72 can be changed in response to a control command from the control unit 9 or by a user's operation input.

[0052] The isolation tank 450 includes a frame 452 that laterally surrounds the periphery of the anode electrode 451, and an electrolytic diaphragm 453 that closes the lower part of the frame 452 to form the bottom of the isolation tank 450. The frame 452 is roughly rectangular in plan view, penetrates in the vertical direction, and is made of a material that is resistant to corrosion by the plating solution L, such as a resin material. The electrolytic diaphragm 453 is formed in a flat or sheet shape from a material that blocks non-ionized substances while allowing metal ions to pass through. For example, the electrolytic diaphragm 453 can be made of a porous resin material, an ion exchange resin material, or the like.

[0053] The electrolytic diaphragm 453 closes the lower part of the frame 452 and forms the bottom surface, thereby forming a rectangular box-shaped isolation tank 450 with an open top. The anode electrode 451 is accommodated in the internal space 454 of this isolation tank 450 as shown by the dashed line arrow. To enable this, the frame 452 constituting the isolation tank 450 has an inner wall that is rectangular in shape in a plan view and is slightly larger than the outer size of the anode electrode 451. In addition, in consideration of the convenience of replacement work associated with wear and tear of the electrode material, it is preferable that the anode electrode 451 be detachable from the isolation tank 450.

[0054] As will be described next, the isolation tank 450 housing the anode electrode 451 is immersed in the plating solution L stored in the plating tank 41.

[0055] FIG. 6 is a schematic diagram showing a state in which the isolation tank is immersed in the plating tank. As shown in FIG. 6(a), the isolation tank 450 is arranged so that at least the lower surface of the electrolytic diaphragm 453 forming the bottom surface of the isolation tank 450 is in contact with the plating solution L stored in the plating tank 41. In addition, the second plating solution L2 is poured into the internal space 454 of the isolation tank 450 to such an extent that the anode electrode 451 is immersed in the solution. The composition of the second plating solution L2 is not particularly limited, but it can be the same as the plating solution L stored in the plating tank 41, for example. Note that the "same composition" here refers to the composition at the time of supply, and the composition may differ as the treatment progresses. In addition, for example, the type of main component may be the same as that of the first plating solution, and the second plating solution may be substantially the same, but the concentration may be different, or at least one of the presence, absence, type, and content of additives may be partially different. In addition, depending on the purpose, a liquid having a different composition from that of the first plating solution may be used as the second plating solution.

[0056] Therefore, inside the plating tank 41, the substrate S supported by the chuck mechanism 400 (upper chuck 411, lower chuck 421) and the anode electrode 451 are positioned facing each other with the plating liquid L (+L2) and the electrolytic diaphragm 453 interposed therebetween.

[0057] A predetermined gap G1 larger than zero is provided between the lower surface of the anode electrode 451 and the upper surface of the electrolytic diaphragm 453. A predetermined gap G2 larger than zero is provided between the lower surface of the electrolytic diaphragm 453 and the upper surface of the substrate S. Therefore, the gap G between the lower surface of the anode electrode 451 and the upper surface of the substrate S is calculated using the thickness t of the electrolytic diaphragm 453 as follows: G=G1+G2+t It is expressed by:

[0058] 5 and 6(b), one output terminal of each of the output units 71a to 71i is individually connected to each of the electrode plates 451a to 451i, while the other output terminals are collectively connected to the cathode electrode 412. Then, as shown in FIG. 4(b), the cathode electrode 412 is provided at the lower end of the upper chuck 411 and is in contact with the upper surface of the substrate S.

[0059] Therefore, when an output current of a predetermined magnitude is output from each of the output ports 71a to 71i of the power supply unit 7, a current flows from the anode electrode 451 through the electrolytic diaphragm 453 toward the upper surface of the substrate S, as shown by the arrow in FIG. 6(b). An electrochemical reaction caused by the action of this current produces a plating film on the upper surface of the substrate S.

[0060] In this electrochemical reaction, the non-uniformity of the current density distribution on the upper surface of the substrate S affects the quality of the plating film. That is, in order to obtain a film with a uniform composition and thickness, it is desirable to obtain a uniform current density distribution in the surface of the substrate S. However, it is not easy to maintain a uniform current density due to the fact that the substrate S is made of glass, which is an insulator, its outer shape is rectangular, and the electrical contact with the cathode electrode 412 is limited to the peripheral portion of the substrate S. In the electrolytic plating technique in which an anode electrode faces one main surface of the substrate and a cathode electrode contacts the peripheral portion of the substrate as in this embodiment, current concentration is likely to occur on the peripheral portion of the substrate. For this reason, the film thickness on the peripheral portion tends to be larger than that in the central portion. In particular, when shortening the tact time of the plating process, it is necessary to increase the amount of current supplied from the power supply unit 7, but this also increases the bias of the current.

[0061] To address this problem, for example, there is a technique for alleviating current concentration by covering the periphery of the substrate with a shield plate. However, for a large substrate such as a glass substrate for a display device, a large shield plate is required to cover the periphery, and the size of the shield plate must be optimized according to the substrate size, which increases the cost of the device. Furthermore, there is not enough knowledge about the size and shape of the shield plate that is effective for a rectangular substrate.

[0062] In this embodiment, the anode electrode 451 is divided into a plurality of electrode plates 451a-451i. Output units 71a-71i capable of setting output currents independently of one another are individually connected to the electrode plates 451a-451i. Therefore, by individually adjusting the amount of current supplied to each of the electrode plates 451a-451i, it is possible to change the density distribution of the current flowing from the anode electrode 451 to the substrate S. This makes it possible to improve the uniformity of the plating film by correcting the bias of the current and bringing the current density closer to a uniform distribution.

[0063] As described above, current concentration is likely to occur at the periphery of a rectangular substrate. In view of this, it can be said that, among the electrode plates 451a to 451i, the amount of current tends to be small in the electrode plate 451e facing the center of the substrate S, and large in the other electrode plates arranged to surround it in the horizontal direction. Therefore, it is expected that the current distribution can be made closer to a uniform one by setting the amount of current to the electrode plate 451e arranged in the center to be larger than that to the other electrode plates.

[0064] In addition, because the cathode electrode 412 is held in contact with both ends of the substrate S in the X direction, it is expected that the current will tend to be larger at the ends in the X direction than at the ends in the Y direction. For this reason, it can be said that it is desirable to apply a larger current to the electrode plates 451b and 451h located at both ends in the Y direction in terms of the arrangement of the electrode plates than to the electrode plates 451d and 451f located at both ends in the X direction.

[0065] In this way, the current input to each of the electrode plates 451a-451i can be determined in advance based on the shape and electrode arrangement of the substrate S. In order to more accurately uniformize the current density, a current distribution may be measured by a preliminary experiment, and a set value of the current to be supplied to each of the electrode plates 451a-451i may be determined for each of the output units 71a-71i so as to correct any bias in the current distribution based on the results.

[0066] For the purpose of uniforming the current density near the substrate surface, the current setting value can be optimized, for example, as follows. Here, the value obtained by dividing the current value given to each electrode plate by the area of ​​the lower surface (surface facing the substrate S) of the electrode plate (hereinafter referred to as the "electrode area") is defined as the "electrode current density". If this electrode current density is considered to represent the current density in the portion of the substrate upper surface Sa facing the electrode plate, the output current value to each electrode plate 451a-451i can be determined so that the electrode current density becomes an appropriate current density at each position on the substrate S. In this way, it is possible to appropriately set the output current value to each electrode plate 451a-451i regardless of whether the electrode areas of the electrode plates 451a-451i are the same or different.

[0067] For example, in the case where the current density tends to be high at the periphery of the substrate S and low at the center, as in the above example, the electrode current density is set to be high in the electrode plate 451e arranged at the center and low in the other electrode plates arranged around it, so that the overall current density distribution can be made uniform. In addition, for electrode plates with a part of the lower surface located outside the substrate S in a plan view and not facing the substrate S, the area of ​​the part facing the substrate S may be considered as the effective electrode area. In addition, unless the peripheral part of the electrode plate protrudes outward considerably from the substrate S, the current output from the part that is actually outside the substrate S can also reach the substrate S and contribute to the plating reaction. In this case, the entire electrode plate may be considered as an effective electrode and included in the electrode area.

[0068] The determined setting values ​​are stored in advance as preset values ​​in the setting storage unit 72 of the power supply unit 7, and these can be read out to operate the output units 71a to 71i. The user and the control unit 9 can change these settings as necessary. This makes it possible to deal with cases where it is necessary to change the current distribution, for example, when changing the size of the substrate S.

[0069] It is also possible to use a material having ion permeability not only for the bottom surface but also for the sidewall surface of the isolation tank 450. However, the movement of ions through the sidewall surface can cause current concentration at the periphery of the substrate, impairing the uniformity of the plating film. By allowing ions to move only through the bottom surface of the isolation tank that faces the top surface of the substrate S, such current concentration can be prevented.

[0070] For the same reason, if the cathode electrode 412 is disposed directly below the electrolytic diaphragm 453 forming the bottom of the isolation tank 450, a current path shorter than the other portions is formed in that portion, causing current concentration. To avoid this, it is preferable that the cathode electrode 412 contacts the substrate S outside the region of the substrate upper surface Sa that faces the anode electrode 451, more preferably outside the bottom of the isolation tank 450, in a plan view.

[0071] In this sense, it is also effective to construct the frame 452 from a material that is not permeable to ions, and to make the outer size of the isolation tank 450 in a plan view (more precisely, the outer size of the electrolytic diaphragm 453 forming the bottom) smaller than the outer size of the substrate S. In these configurations, ions are prevented from moving through any route other than the electrolytic diaphragm 453, so it can be said that the isolation tank itself fulfills the same function as a blocking plate in the prior art. As shown in FIG. 6(b), these conditions are met in this embodiment.

[0072] In the electrolytic plating process carried out in this manner, a metal soluble in the plating solution L, which is an electrolytic solution, can be used as the anode electrode 451 to form a plating film of the metal on the surface of the substrate S. For the purpose of forming a copper plating film on the substrate S, which is, for example, a glass substrate, it is suitable to use, for example, an aqueous copper sulfate solution as the plating solution L (L2) and, for example, a copper plate as the anode electrode 451.

[0073] When a DC voltage is applied between the anode electrode 451 and the cathode electrode 412 and a current is supplied to the anode electrode 451, a metal material (e.g., copper) is ionized from the anode electrode 451 and dissolved into the plating solution L2. The ionized metal passes through the electrolytic diaphragm 453 and the plating solution L and adheres to the upper surface of the substrate S to form a plating film. In other words, the anode electrode 451 in this plating reaction is a so-called soluble electrode that contains material that is consumed to form the plating film.

[0074] In this process, the anode electrode 451 gradually dissolves into the plating solution L (L2), and at this time, insoluble impurities contained in the electrode material are liberated into the solution from the anode electrode 451. The insoluble residue thus generated in the plating solution is sometimes called "anode slime" or "anode mud."

[0075] In this embodiment, the substrate S is supported in a horizontal position with the surface to be plated facing upward, and the anode electrode 451 is disposed above the substrate S. As a result, anode slime consisting of impurities liberated from the anode electrode 451 settles in the plating solution toward the substrate S disposed below. If such impurities adhere to the upper surface of the substrate S, which is the surface to be plated, this can cause plating defects and reduce the quality of the plating film.

[0076] To address this problem, in this embodiment, the anode electrode 451 and the substrate S are isolated by an isolation layer 450. Specifically, an electrolytic diaphragm 453 is disposed between the lower surface of the anode electrode 451 and the upper surface of the substrate S, and the sides of the anode electrode 451 are surrounded by a frame 452. The isolation tank 450 is immersed in the plating solution L in the plating tank 41, and the internal space 454 is filled with a plating solution L2 having the same composition as the plating solution L.

[0077] Therefore, for the metal ions involved in the plating reaction, a path from the anode electrode 451 to the substrate S via the plating solutions L, L2 and the electrolytic diaphragm 453 is secured, while for the liquid components and insoluble components in the plating solution, the anode electrode 451 and the substrate S are isolated from each other by the isolation tank 450. For this reason, the anode slime generated by the aggregation of the insoluble components is blocked by the electrolytic diaphragm 453 and does not adhere to the substrate S.

[0078] In addition, since the box-shaped isolation tank 450 has an opening at its top, the upper part of the anode electrode 451 contained in the isolation tank 450 is open. Therefore, the anode electrode 451 can be easily attached / detached from the isolation tank 450. As the reaction progresses, the anode electrode 451 wears out and must be replaced periodically. The above structure contributes to increasing the convenience of such replacement work.

[0079] The anode electrode 451 is divided into a plurality of electrode plates 451a to 451i. Therefore, the replacement work can be performed for each electrode plate. This improves the workability of the replacement work, and also leads to effective use of resources because only the electrode plate of the anode electrode 451 that needs to be replaced can be replaced.

[0080] The interval between the electrode plates 451a-451i in the horizontal direction can be, for example, smaller than the distance between the lower surface of each electrode plate 451a-451i and the substrate S, and more preferably, can be set to half or less of the distance. If the interval between the electrode plates is large, a sufficient current may not be supplied to the area of ​​the substrate upper surface Sa that does not face any of the electrode plates, causing unevenness in the current density. It is known that the current flowing out from the electrode plate has a certain degree of spread from the outer edge of the electrode plate in the liquid. According to the knowledge of the inventor of the present application in this regard, it is possible to suppress such current unevenness by setting the interval as described above.

[0081] Next, a mechanism for supporting the isolation tank 450 in the anode electrode unit 45 will be described. Due to the structural constraints that the bottom surface of the isolation tank 450 is disposed opposite the substrate S and that the isolation tank 450 is immersed in the plating solution L stored in the plating tank 41, the support mechanism for the isolation tank 450 needs to be provided above the isolation tank 450. In addition, in order to refresh the plating solution L2 and suppress the accumulation of anode slime on the electrolytic diaphragm 453, it is desirable to periodically replace the plating solution L2 stored in the isolation tank 450. The support mechanism described below meets such requirements.

[0082] Fig. 7 is an external perspective view showing a support mechanism for the isolation tank in the anode electrode unit. Note that in Fig. 7, in order to clearly show the structure of the support mechanism, the illustration of the anode electrode 451 accommodated in the internal space 454 of the isolation tank 450 is omitted. In the anode electrode unit 45, the isolation tank 450 is attached to the housing 10 via a support mechanism 460. The support mechanism 460 supports the isolation tank 450 so that it can be moved up and down relative to the plating tank 41 fixed to the frame 10.

[0083] The support mechanism 460 includes support frames 461, 462, and 463 arranged in the vertical direction (Z direction). These support frames are related in such a way that the first support frame 461 arranged at the bottom supports the isolation tank 450, the second support frame 462 arranged above supports the first support frame 461, the third support frame 463 arranged further above supports the second support frame 462, and the third support frame 463 is fixed to the upper frame 11 of the housing 10 (FIGS. 1 and 3(a)).

[0084] Each of the support frames 461 to 463 has a roughly rectangular outer shape and a frame-like structure with a central portion penetrating in the vertical direction. Four sets of lift guide mechanisms 466 whose operating direction is the vertical direction are attached to the third support frame 463 at the top of the frames. Specifically, linear bushes 466a of the lift guide mechanisms 466 are provided at the four corners of the support frame 463. The linear bushes 466a are hollow cylindrical members penetrating in the vertical direction, and a movable rod 466b is inserted into the hollow portion. The movable rod 466b extends downward from the linear bushes 466a, and its lower end is connected to the second support frame 462 below.

[0085] When the lifting mechanism 47, which will be described later, operates in response to a control command from the control unit 9, the movable rod 466b moves up and down within a predetermined movable range, whereby the second support frame 462 connected to the lower end of the movable rod 466b moves up and down. At this time, the first support frame 461 supported by the second support frame 462 and the isolation tank 450 supported by the first support frame 461 also move up and down in the same manner.

[0086] Similarly, four sets of lift guide mechanisms 465, each of which operates in the up-down direction, are attached to the second support frame 462. Specifically, bushes 465a of the lift guide mechanisms 465 are provided at the four corners of the support frame 462, and movable rods 465b are inserted into the linear bushes 465a. The movable rods 465b extend downward from the linear bushes 465a, and their lower ends are connected to the first support frame 461 below.

[0087] When the lifting mechanism 47 operates in response to a control command from the control unit 9, the movable rod 465b moves up and down within a predetermined movable range, whereby the first support frame 461 connected to the lower end of the movable rod 465b moves up and down. At this time, the isolation tank 450 supported by the first support frame 461 also moves up and down in the same manner.

[0088] In this way, the lift guide mechanisms 465, 466 can move the isolation tank 450 in the up and down direction in cooperation with the lift guide mechanism 47. As the lift guide mechanisms 465, 466, various mechanisms other than the combination of the cylindrical linear bush and the movable rod described above can be applied. For example, various mechanisms that can restrict the movement of the object in one direction can be used, such as a linear guide mechanism that combines a guide rail and a slider. Note that the lift guide mechanisms 465, 466 may be provided with a damper function, similar to the lift guide mechanism 464 described next.

[0089] Meanwhile, the first support frame 461 supports the isolation tank 450 so that it can move up and down and tilt around the X-axis. Specifically, four sets of lifting guide mechanisms 464 are attached to the first support frame 461, and movable rods 464b extend downward from linear bushes 464a of the lifting guide mechanisms 464. As described below, the lifting guide mechanisms 464 have a damper mechanism, which reduces the impact transmitted to the isolation tank 450 when the isolation tank 450 is lifted or lowered.

[0090] Further, a frame 455, which is a combination of a plate member 455a extending in the X direction and a plate member 455b extending in the Y direction, is attached to the upper part of the frame 452 constituting the isolation tank 450, and hinge members 455c are attached to four points on the upper part of the frame 455. The lower ends of the movable rods 464b extending from the four lift guide mechanisms 464 are engaged with the hinge members 455c located directly below them, and are attached so as to be rotatable around an axis parallel to the X axis. In this manner, the isolation tank 450 is supported by the support frame 461 via the support mechanism 460.

[0091] In addition, between the two hinge members 455c, 455c arranged on the (-Y) side among the four hinge members 455c, a roller member 455f rotatably supported by an appropriate support member is provided. The roller member 455f is not connected to a drive mechanism and can rotate freely. The function of the roller member 455f will be described later.

[0092] Moreover, equipment for supplying and discharging plating solution L2 to and from the isolation tank 450 is disposed around the isolation tank 450. That is, a nozzle 491 for discharging the plating solution sent from the plating solution supply and discharge part 49 toward the internal space 454 of the isolation tank 450 is provided above the isolation tank 450. The nozzle 491 is attached to the frame 455 via an appropriate fixing member.

[0093] Plating solution supply / discharge unit 49 and nozzle 491 are connected by piping 492 to form a supply path for the plating solution, and flexible joint 493 is provided in piping 492 at a position close to isolation tank 450. A flexible joint is a piping component in which at least a portion of the piping is made of a flexible material such as rubber, and is inserted into a portion of a piping system mainly made of non-flexible tubing material to allow the piping to bend at the insertion point. Flexible joints are widely used, for example, for the purpose of absorbing mutual positional deviations and vibrations at the connection points between pipes.

[0094] As described later, in order to efficiently discharge the plating solution, the isolation tank 450 is provided so as to be rotatable about the X-axis. By inserting a flexible joint 493 into the pipe 492, it is possible to form a supply path for the plating solution between the plating solution supply / discharge part 49 and the nozzle 491 while allowing such rotation.

[0095] The isolation tank 450 is also provided with a pipe for discharging the plating solution stored in the internal space 454 to the plating solution supply / discharge unit 49. Specifically, a through hole 452a is provided in the lower part of the side surface on the (+Y) side of the frame 452 constituting the isolation tank 450, and a discharge pipe 494 is connected to this through hole 452a. As with the plating solution supply pipe 492, a flexible joint 495 is also inserted into the discharge pipe 494.

[0096] Furthermore, above the anode electrode unit 45, a lifting mechanism 47 fixed to the frame 11 of the housing 10 is provided. For the purpose of explaining the principle, the lifting mechanism 47 is assumed to be a winch mechanism that lifts and lowers an object by winding up a wire. That is, a wire 471 hangs downward from the lifting mechanism 47, and the wire 471 reaches a position directly above the isolation tank 450 through openings in the center of each of the support frames 461 to 463. The lower end of the wire 471 is attached to a connecting portion 455d provided on the frame 455. The connecting portion 455d provided on the frame 455 is disposed at a position closer to the (-Y) side than the middle position between the two hinge members 455c, 455c arranged in the Y direction.

[0097] The lifting mechanism 47 operates in response to a control command from the control unit 9, and moves the isolation tank 450 up and down together with the frame 455 connected to the wire 471. Such up and down movement of the isolation tank 450 can be achieved using various drive mechanisms other than those described above. For example, a known linear motion mechanism such as a ball screw mechanism, an air cylinder mechanism, or a linear motor mechanism, or a device commercially available as a Zip Chain Actuator (registered trademark) can be suitably applied.

[0098] Fig. 8 is a diagram showing a schematic diagram of the supply and discharge of plating solution to and from the isolation tank. Although simplified in Fig. 7, as shown in Fig. 8(a), the lift guide mechanism 464 includes a linear bush (also called a linear bearing or linear bearing) 464a into which a movable rod 464b extending in the vertical direction (Z direction) is inserted, a base member 464c to which the linear bush 464a is attached, a plate-shaped bracket 464d attached to the upper end of the movable rod 464b, and a damper mechanism 464e provided between the plate member 464d and the base member 464c. As the damper mechanism 464e, for example, a known shock absorber can be applied.

[0099] The movable rod 464b is inserted into the linear bushing 464a so as to be movable up and down. When the movable rod 464b moves up and down, the bracket 464d also moves up and down accordingly. When the bracket 464d descends, it comes into contact with the damper mechanism 464e, and further downward displacement is restricted. In other words, the damper mechanism 464e has a function of allowing the movable rod 464b to move up and down, while regulating its movable range, and also mitigating the impact when the descent stops.

[0100] Two sets of lift guide mechanisms 464 are provided at different positions in the Y direction. The lower ends of movable rods 464b of each lift guide mechanism 464 are engaged with hinge members 455c attached to the frame 455 of the isolation tank 450. As a result, the isolation tank 450 is supported in a substantially horizontal position in a steady state.

[0101] With the isolation tank 450 supported in a substantially horizontal position in this manner, as shown by the outlined arrow in Fig. 8(a), the plating solution L2 is supplied to the isolation tank 450 from the plating solution supply / discharge unit 49 through the piping 491. The plating solution L2 is discharged from a discharge port provided on the lower surface of the nozzle 491 toward the internal space 454 of the isolation tank 450, and thus the plating solution L2 is supplied to the isolation tank 450. With the anode electrode 451 immersed in the plating solution L2, a plating process is performed.

[0102] After the plating process is completed, the plating solution L2 in the internal space 454 can be refreshed by discharging the existing plating solution and refilling it with new plating solution. However, when discharging the plating solution L2 from the isolation tank 450, a discharge path cannot be provided below the isolation tank 450 because the substrate S is placed directly below the isolation tank 450.

[0103] It is also possible to flow the plating solution L2 from the isolation tank 450 into the plating tank 41 and discharge the plating solution L2 through the plating tank 41. However, doing so would result in the anode slime contained in the plating solution L2 being mixed into the plating tank 41, so it is preferable to discharge the plating solution L2 through a route independent of the discharge from the plating tank 41.

[0104] For the same reason, when supplying plating solution to isolation tank 450 and when tilting isolation tank 450 to promote drainage, as described below, it is necessary to prevent plating solution L2 from overflowing from isolation tank 450 and flowing into plating tank 41.

[0105] In order to discharge the plating solution while satisfying these requirements, a discharge port is provided on the side wall of the isolation tank 450 to discharge the plating solution to the side, but this inevitably impairs the smoothness of discharge compared to when a discharge port is provided on the bottom surface. Therefore, in this embodiment, a through hole 452a is provided as a discharge port on the (+Y) side surface of the isolation tank 450, and a discharge pipe 494 is connected to the through hole 452a. When discharging the plating solution L2, the isolation tank 450 is lifted on the side opposite to the discharge port, i.e., the (-Y) side, to incline the bottom surface. This can promote the discharge of the plating solution L2 from the internal space 454.

[0106] Specifically, by winding up wire 471, lifting mechanism 47 can pull up frame 455 and lift the (-Y) side end of isolation tank 450, as shown by the dashed arrow in Fig. 8(b). In this way, isolation tank 450 is inclined with its bottom surface inclined relative to the horizontal plane, so that plating solution L2 stored in internal space 454 flows toward through hole 452a, which serves as a discharge port, as shown by the hollow arrow in Fig. 8(b). In this way, discharge of plating solution L2 is promoted. Waste liquid that has flowed into piping 494 is collected by plating solution supply and discharge unit 49.

[0107] The manner in which the isolation tank 450 is supported by the lift guide mechanism 464 connected via the rotatable hinge member 455c allows such tilting of the isolation tank 450. That is, in a pair of lift guide mechanisms 464, 464 disposed at different positions in the Y direction, the movable rods 464b move up and down independently of each other, thereby realizing a tilted state of the isolation tank 450.

[0108] Moreover, flexible joints 493, 495 are inserted in a plating solution supply pipe 492 and a discharge pipe 494 connected to the isolation tank 450. Therefore, the isolation tank 450 can be tilted with these pipes still connected.

[0109] 9 to 11 are diagrams for explaining the lifting and lowering operation of the isolation tank in more detail, and more specifically, for explaining the action of the roller member 455f. In these diagrams, in order to facilitate understanding, some components that are not necessary for the explanation may be omitted or the structure may be simplified. In addition, in order to explain the action of the roller member 455f hidden by the hinge member 455c, its installation position is shifted to the (+Y) side from the actual position.

[0110] 9, a rotatable roller member 455f is provided on the upper part of isolation tank 450. Furthermore, a tapered member 468, whose lower surface is an inclined surface inclined with respect to the horizontal plane, is attached to the lower surface of support frame 461 at a position directly above roller member 455f. When lifting mechanism 47 is operated and wire 471 is wound up as shown by the dashed arrow, isolation tank 450 is pulled upward while remaining in an inclined position, and roller member 455f and tapered member 468 gradually approach each other.

[0111] 10, roller member 455f comes into contact with the lower surface, i.e., the inclined surface, of tapered member 468, thereby restricting further upward displacement of roller member 455f. If isolation tank 450 is pulled further upward in this state, the rise of the (-Y) side end of isolation tank 450 is restricted by roller member 455f and tapered member 468, while the (+Y) side end of isolation tank 450 has room to rise further.

[0112] Therefore, the (+Y) side end of the isolation tank 450 is further lifted, and finally, the isolation tank 450 is held in a horizontal position as shown in Fig. 11. Thus, in the process of lifting the isolation tank 450 from the plating tank 41, the isolation tank 450 is temporarily tilted to discharge the plating solution L2, but the isolation tank 450 is eventually returned to the horizontal position.

[0113] When the isolation tank 450 descends from the retreated position, the above-mentioned operation is reversed. That is, the isolation tank 450 temporarily tilts from the horizontal position, but returns to the horizontal position when it is accommodated in the plating tank 41. In this way, it becomes possible to receive a new supply of plating solution L2.

[0114] Fig. 12 is a diagram showing the lifting and lowering operation of the entire support mechanism. The above describes the operation of the lifting guide mechanism 464 that lifts and lowers the isolation tank 450 relative to the support frame 461. As shown in Fig. 7, this support mechanism 460 has a structure in which the support frame 461 is supported by a lifting guide mechanism 465 attached to a support frame 462, and the support frame 462 is further supported by a lifting guide mechanism 466 attached to a support frame 463.

[0115] The structure and operation of the lift guide mechanisms 465 and 466 are the same as those of the lift guide mechanism 464, except that the damper mechanism is omitted. Therefore, the support frame 461 can be raised and lowered relative to the support frame 462, and the support frame 462 can be raised and lowered relative to the support frame 463. Therefore, the support mechanism 460 can transition between a state in which the support frames 461 and 462 are lowered to the lowest position relative to their respective supporting bodies, as shown in the upper diagram of Fig. 12, and a state in which the support frames 461 and 462 are raised to the highest position relative to their respective supporting bodies, as shown in the lower diagram of Fig. 12. Since the support frame 463 is fixed to the upper frame 11 constituting the equipment housing 10, such a structure contributes to increasing the vertical movable range of the isolation tank 450.

[0116] Fig. 13 is a block diagram showing the electrical configuration of this plating apparatus. In the plating apparatus 1 configured as above, the control unit 9 controls each unit of the apparatus to cause the plating apparatus 1 to perform a predetermined process. The hardware configuration of the control unit 9 can be the same as that of a general computer device, for example. That is, the control unit 9 can be equipped with a CPU (Central Processing Unit) 91, memory 92, storage 93, input unit 94, display unit 95, interface unit 96, etc.

[0117] The memory 92 temporarily stores various data generated during the process. The storage 93 long-term stores various data and a control program 931. The input unit 94 and the display unit 95 perform a user interface function. The interface unit 96 performs communication with external devices and the like.

[0118] The CPU 91 reads out and executes a control program 931 stored in advance in the storage 93, and controls each part of the apparatus based on the control program to perform a predetermined operation, thereby implementing various operations described below. For this purpose, the CPU 91 realizes, in software, functional blocks such as a transfer control unit 911 that controls the operation of the transfer unit 2, a chuck control unit 912 that controls the operation of the chuck unit 40, a supply and discharge control unit 913 that controls the supply sources of various fluids to manage their supply and discharge, a flow rate control unit 914 that controls valves on the piping to adjust the flow rate of the circulating fluid, and a power supply control unit 915 that controls the power supply to the electrodes by the power supply unit 7. At least some of these functional blocks may be configured as dedicated hardware, for example.

[0119] In addition, the specification and drawings of Patent Application No. 2022-094449 previously disclosed by the applicant of the present application disclose a plating apparatus having a basic configuration similar to that of the plating apparatus 1 of this embodiment, and include detailed descriptions of the structure and functions of each part of the apparatus, as well as the operation of the apparatus.

[0120] Next, the operation of the plating apparatus 1 configured as described above will be described. The basic operational flow of the plating apparatus 1 is roughly as follows. An unprocessed substrate S is carried into the carry-in section 3. The substrate S is transported from the carry-in section 3 to the plating section 4, which performs electrolytic plating on the substrate S to form a metal coating on its surface (upper surface Sa). The plated substrate S is rinsed in the rinsing section 5 and is finally carried out to the unloading section 6.

[0121] FIG. 14 is a flow chart showing the plating process. FIG. 15 is a diagram showing the operation of each part. More specifically, FIG. 15 shows the operation of each part as time T progresses, with the time axis being from top to bottom. After an unprocessed substrate S is provided to the loading part 3 at time T0, each part of the apparatus performs the following operations. In the figure, the parentheses indicate the initial state of each part. In FIG. 15, the parts of each processing part shown with thick vertical lines indicate that the substrate S is present in that processing part.

[0122] Each part of the plating apparatus 1 is set in advance to a predetermined initial state. In the initial state, the chuck mechanism 400 is positioned at a plating position above the plating tank 41, and the upper chuck 411 and the lower chuck 421 are positioned at upper positions that do not interfere with the plating tank 41. Note that the upper chuck 411 and the lower chuck 421 may be positioned lower as long as they do not impede the transport of the substrate S along the transport path P.

[0123] In the loading section 3, the loaded substrate S is temporarily stored. In the plating processing section 4, the shutters 41a and 41b of the plating tank 41 are opened, allowing the substrate S to be transported along the transport path P. At this time, the plating tank 41 is stored to a height such that the plating solution supplied from the plating solution supply / discharge section 49 does not flow out of the opening. In the anode electrode unit 45, the isolation tank 450 is retracted upward, and no plating solution is stored in the internal space 454. In the rinsing processing section 5, the shutters 51a and 51b of the rinsing tank 51 are also opened, allowing the substrate S to be transported along the transport path P. At this time, the substrate S is not present in the unloading section 6.

[0124] At time T1, the transport unit 2 starts transporting the substrate S, and the substrate S is transported in the transport direction Dt (+Y direction) along the transport path P, and is finally transported to the plating tank 41 (step S101). In Fig. 15, the dashed arrow indicates the transfer of the substrate S by the transport unit 2.

[0125] When the substrate S is carried into the plating tank 41, the shutters 41a and 41b are closed. The upper chuck 411 and the lower chuck 421 of the chuck mechanism 400 are lowered toward the substrate S accommodated in the plating tank 41 to grip the substrate S (step S102). In the anode electrode unit 45, the isolation tank 450 is lowered and disposed to face the upper surface of the substrate S held in the plating tank 41. Note that the substrate S may be transported to the plating tank 41 with the isolation tank 450 already lowered.

[0126] In this state, the plating solution L is supplied from the plating solution supply / discharge unit 49 to the plating tank 41 (step S103). In parallel with this, the plating solution L2 is supplied from the plating solution supply / discharge unit 49 to the isolation tank 450. As a result, a state is realized in which the substrate S is immersed in the plating solution L in the plating tank 41, the anode electrode 451 is immersed in the plating solution L2 in the isolation tank 450, and the lower surface of the electrolytic diaphragm 453 on the bottom surface of the isolation tank 450 is in contact with the plating solution L in the plating tank 41 (FIG. 6(a)).

[0127] Then, a predetermined current is output from each output portion 71a of the power supply 7 (step S104), whereby the substrate S is plated. By contacting the cathode electrodes extending long in the Y direction with both ends in the X direction of the upper surface Sa of the substrate S, the variation in current density on the upper surface Sa of the substrate S is suppressed, and it becomes possible to form a plating film with good uniformity.

[0128] At this time, the chuck mechanism 400 and the transport rollers 21 work together to oscillate the substrate S in the plating tank 41 (step S105), thereby further improving the uniformity of the plating film. Specifically, the movement mechanism 43 is actuated to cause the support frame 430 supporting the chuck mechanism 400 to alternately move in the (+Dt) direction and the (-Dt) direction. As a result, the chuck mechanism 400 attached to the support frame 430 moves back and forth integrally in the Y direction, and the substrate S held by the chuck mechanism 400 oscillates in the Y direction in the plating solution L.

[0129] At this time, the transport rollers 21 work in conjunction with the support frame 430. That is, when the support frame 430 moves in the (+Y) direction and the chuck mechanism 400 moves the substrate S in the (+Y) direction, the transport rollers 21 rotate in the forward direction, that is, in the direction transporting the substrate S in the transport direction Dt. On the other hand, when the support frame 430 moves in the (-Y) direction and the chuck mechanism 400 moves the substrate S in the (-Y) direction, the transport rollers 21 rotate in the reverse direction, that is, to transport the substrate S in the direction (-Dt) opposite to the transport direction Dt.

[0130] By rocking the substrate S in the plating solution L in this manner, the plating solution L is stirred, reducing bias in the ion concentration in the solution and improving the uniformity of the plating film. The rocking of the substrate S in the plating tank 41 is achieved by the cooperation of a chuck mechanism 400 that grips the edge of the substrate S and a transport roller 21 that supports the center of the substrate S from the underside. This makes it possible to prevent local stress from being applied to the substrate S and to rock the substrate S while maintaining a horizontal position.

[0131] After the substrate S is immersed in the plating solution L and the state in which the substrate S is oscillated while a current is supplied between the electrodes is continued for a certain period of time, the current supply is stopped (step S106), thereby stopping the plating process. Then, the plating solution L is discharged from the plating tank 41, and the plating solution L2 is discharged from the isolation tank 450 (step S107). When discharging from the isolation tank 450, the lifting mechanism 47 is operated to lift the (-Y) side end of the isolation tank 450 while the isolation tank 450 is retracted upward by the support mechanism 460.

[0132] Then, the substrate S is released from the chuck mechanism 400 (step S108), the shutter 41b is opened, and the transport unit 2 transfers the substrate S from the plating unit 4 to the rinsing unit 5 at time T2 (step S109). By releasing the substrate S from the plating unit after the plating solution L is discharged, it is possible to prevent the cathode electrode 412 from coming into contact with the plating solution. There is no such restriction for the anode electrode 451. Therefore, the discharge from the isolation tank 450 can be performed at any timing after the current is stopped. In other words, it is not necessary to be performed simultaneously with the discharge of the plating solution L from the plating tank 41.

[0133] In the rinsing processing unit 5, when the substrate S is accommodated in the rinsing tank 51, the shutters 51a and 51b are closed, and a rinsing liquid is supplied from the rinsing liquid supply / discharge unit 59 to rinse the substrate S (step S110). After the rinsing process is performed for a predetermined time, the supply of the rinsing liquid is stopped, the shutter 51b is opened, and at time T3, the substrate S is discharged to the unloading unit 6 (step S111).

[0134] When discharging the plating solution from the plating tank 41, it is not necessary to completely drain the liquid in the tank. In other words, as long as the liquid is discharged to the extent that the substrate S supported in the tank is exposed from the liquid and can be removed, there is no problem with the liquid remaining in the tank. In fact, by leaving the liquid remaining, it is possible to reduce the amount of liquid required to fill the tank when processing the next substrate S. This contributes to reducing the consumption of liquid and the environmental load.

[0135] Meanwhile, after releasing the grip of the substrate S, the chuck mechanism 400 undergoes a cleaning process to remove the plating solution adhering to the upper chuck 411 and the lower chuck 421 (step S112). The cleaning process may be carried out in any manner, but an example thereof is as follows. That is, the support mechanism 43 moves the support frame 430 in the (-Y) direction to position each chuck mechanism 400 at a cleaning position above the vat 44. In this state, the cleaning mechanism 48 cleans the chuck mechanism 400, more specifically, the upper chuck 411 and the lower chuck 421, by supplying an appropriate cleaning liquid or injecting air.

[0136] When the chuck mechanism 400 moves between the plating position and the cleaning position, the upper chuck 411 and the lower chuck 421 are retracted upward by the lifting mechanisms 412, 422, as shown by the dotted lines in Fig. 2. This prevents the upper chuck 411 and the lower chuck 421 from contacting the wall surface of the plating tank 41 during the movement. The Z direction positions of the upper chuck 411 and the lower chuck 421 at this time will be referred to as the "upper position" hereinafter.

[0137] After cleaning, the chuck mechanism 400 is returned to the plating position (step S113). By cleaning the chuck mechanism 400 in this manner, it is possible to prevent the remaining plating solution from adhering to the substrate S when processing the next substrate S. If there is another substrate S to be processed, the process returns to step S101 and the above processing is repeated.

[0138] As described above, in the plating apparatus of this embodiment, the substrate S, which is the object of plating, is supported in the plating tank 41 in a horizontal position with one main surface Sa, which is the surface to be plated, facing upward, that is, in a so-called face-up state. The cathode electrode 412 contacts the peripheral portion of the substrate S, and the anode electrode 451 is disposed opposite the upper surface of the substrate S.

[0139] However, the anode electrode 451 and the substrate S are separated by an electrolytic diaphragm 453. This ensures a path between the anode electrode 451 and the substrate S for metal ions that are the material of the plating film, while isolating the anode electrode 451 and the substrate S for non-soluble components and liquid components. This prevents anode slime generated by substances liberated from the anode electrode 451 from adhering to the substrate S and degrading the quality of the plating film.

[0140] The anode electrode 451 is divided into a plurality of electrode plates 451a-451i, and output units 71a-71i, which are constant current sources of the power supply unit 7, are individually connected to the respective electrode plates. The output current from each of the output units 71a-71i can be individually set. Therefore, even if the substrate S is large, it is possible to suppress unevenness in the current density distribution within the surface of the substrate S and to achieve a uniform thickness of the plating film.

[0141] Furthermore, with regard to replacement of the plating solution in the isolation tank 450, since the bottom surface of the isolation tank 450 is disposed opposite the substrate S, it is difficult to provide a mechanism for draining the solution below the isolation tank 450. Therefore, in this embodiment, a drain outlet is provided on the side wall surface of the isolation tank 450. Furthermore, in order to efficiently drain the solution, a mechanism for lifting the end of the isolation tank 450 and tilting the bottom surface is provided on the side opposite to the side wall surface on which the drain outlet is provided. This promotes drainage of the plating solution.

[0142] That is, the isolation tank 450 of this embodiment can be switched between a horizontal position where the bottom surface is horizontal and an inclined position where the bottom surface is significantly inclined with respect to the horizontal plane. In the horizontal position, the anode electrode 451 can be placed opposite the substrate S for plating, while in the inclined position, the plating solution remaining in the internal space 454 of the isolation tank 451 can be efficiently discharged and new plating solution can be received thereafter, thereby keeping the plating solution stored in the internal space 454 fresh.

[0143] <Modification> FIG. 16 is a diagram showing a modified example of the anode electrode. The anode electrode 451 in the above embodiment is formed by arranging nine electrode plates 451a to 451i having substantially the same shape in a 3×3 matrix. However, the pattern for dividing the anode electrode into a plurality of parts is not limited to this, and various patterns are possible. For example, in the anode electrode 456 shown in FIG. 16(a), electrode plates having substantially the same shape are arranged in a 5×4 matrix. In this way, the number of electrode plates arranged is not limited to that in the above embodiment, and can be any number.

[0144] 16(b), a large-area electrode plate is arranged in the center where a relatively uniform current density can be obtained, while the area of ​​the electrode plate is made smaller in the peripheral and corner areas where the current density is likely to be biased, making it easier to fine-tune the current density distribution. In this way, the shape and size of each electrode plate can be appropriately determined according to the purpose.

[0145] 16(c) has a structure in which a rectangular electrode plate arranged in the center is surrounded by multiple frame-shaped electrode plates with a rectangular outline and an opening in the center. With such a structure, it is possible to achieve the object of setting the current density independently in the center and the periphery of the substrate S.

[0146] Thus, various division patterns of the anode electrode are possible. When setting the division pattern and distributing the current to each electrode plate, for example, a method can be adopted in which the current density distribution is actually measured by a preliminary experiment and the current is determined based on the results. Specifically, in an area of ​​the substrate surface where the current density fluctuation is small, there is little need to finely divide the opposing electrode plate, and conversely, in an area where the current density fluctuation is large, finely dividing the electrode plate makes it easier to adjust the current density distribution. In addition, the current setting value can be reduced in areas where the current density is higher, thereby making the current density uniform.

[0147] In particular, when two opposing sides of the four sides of a rectangular substrate are chucked, the cathode electrodes are placed near these two sides, so it is expected that the current distribution will be significantly different from the two sides that are not held. Even in such a case, it is possible to suppress bias in the current density distribution and improve the uniformity of the plating film by adjusting the division pattern of the anode electrode and the current value supplied to each electrode plate.

[0148] FIG. 17 is a diagram showing a schematic diagram of a modified example of the support mechanism in the anode electrode unit. Note that, here, the same reference numerals are used for the configurations common to or corresponding to the above embodiment, and the description thereof will be omitted. In the above embodiment, the isolation tank 450 is tilted by the lift mechanism 47 winding up the wire 471 attached to the isolation tank 450 at a position offset in the Y direction from the midpoint of the two hinge members 455c arranged in the Y direction. Instead of this, for example, as shown in FIG. 17(a), a configuration can be adopted in which the isolation tank 450 is supported by two suspension mechanisms 467a, 467b having significantly different spring constants. That is, the isolation tank 450 is supported by the suspension mechanisms 467a, 467b attached to the support frame 461 being coupled to the frame 455 of the isolation tank 450.

[0149] In order to maintain the isolation tank 450 in a horizontal position, it is preferable to appropriately provide a stopper 469 that restricts downward displacement of the isolation tank 450. Note that the shape and the location of the stopper are not limited to those shown in the figure, and are arbitrary as long as they can directly or indirectly restrict the downward displacement of the isolation tank 450.

[0150] As shown in FIG. 17(b), when the support mechanism 460 lifts the support frame 461, the two suspension mechanisms 467a and 467b have different spring constants, so the isolation tank 450 is inclined. In the example shown in FIG. 17(b), the spring constant of the support mechanism 467a provided on the (-Y) side is greater than the spring constant of the suspension mechanism 467b provided on the (+Y) side, so the (-Y) side end of the isolation member 450 is lifted. This provides the same effect as the above embodiment. Note that, in this case where the support mechanism 460 itself supports the isolation tank 450 via a structure for tilting the isolation tank 450, the lift mechanism 47 may lift and lower the isolation tank 450 using the intermediate position in the Y direction of the two hinge members 455c as the point of action.

[0151] <Other> As described above, in the above embodiment, the plating apparatus 1 corresponds to the "plating apparatus" of the present invention, and the plating tank 41, the chuck mechanism 400, the cathode electrode 412, the anode electrode 451, the power supply unit 7, and the isolation tank 450 function as the "treatment tank", "holding unit", "cathode electrode", "anode electrode", "power supply unit", and "isolation unit" of the present invention, respectively. In the isolation tank 450, the frame 452 and the electrolytic diaphragm 453 correspond to the "side wall" and "bottom" of the present invention, respectively. The plating solution L and the plating solution L2 correspond to the "plating solution" and "liquid" of the present invention, respectively. The support mechanism 46 and the winch mechanism 47 of the anode electrode unit 45 function as the "tilt mechanism" of the present invention. In this embodiment, the nozzle 491 functions as the "supply unit" of the present invention, while the plating solution supply and discharge unit 49 functions as the "supply source" and "recovery unit" of the present invention.

[0152] The present invention is not limited to the above-mentioned embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above-mentioned embodiment, the chuck mechanisms 400 are provided for two opposing sides of the rectangular substrate S. However, instead of this, all four sides or three of the four sides may be gripped by the chuck mechanisms.

[0153] Also, for example, in the above embodiment, the chuck mechanism 400 grips the substrate S transported into the plating tank 41 by the transport rollers 21. However, the transport means is not limited to rollers and is optional. On the other hand, a mode in which the substrate is transported while being gripped by the chuck mechanism is also conceivable. In this case, the transport means is not an essential component, but in order to stably maintain the posture of a large substrate, it is desirable to provide some kind of backup means that supports the center of the substrate S from below.

[0154] It should be noted that the substrate to be processed does not necessarily have to be a geometric rectangle in the strict sense of the word. For example, even if one of the sides of the substrate has some irregularities, it is sufficient if the envelope outline can be regarded as being approximately rectangular.

[0155] Furthermore, for example, the power supply unit 7 in the above embodiment includes a constant current output source that individually corresponds to each of the electrode plates that constitute the anode electrode 451. Alternatively, the power supply unit may be configured by, for example, a combination of a single voltage source and a plurality of current limiting elements provided corresponding to each of the electrode plates.

[0156] Also, for example, in the power supply unit 7 of the above embodiment, individual output units are provided for all of the electrode plates constituting the anode electrode 451. However, some of the electrode plates may be electrically connected in parallel and connected to a common output unit. For example, even in the case of the anode electrode 456 having the division pattern shown in FIG. 16(a), it is possible to realize a division pattern substantially the same as that of the anode electrode 457 shown in FIG. 16(b) by connecting some electrode plates in parallel. Also, the connection relationship between the electrode plates and the power supply may be changed as necessary.

[0157] Furthermore, for example, in the above embodiment, the anode electrode 451 is divided into multiple electrode plates, but the effect of preventing adhesion of anode slime to the substrate, which is obtained by isolating the anode electrode and the substrate by an isolation tank, can be similarly obtained in a plating apparatus in which the anode electrode is constituted by a single electrode plate.

[0158] In addition, in the above embodiment, the liquid stored in plating tank 41 and the liquid stored in isolation tank 451 are plating solutions having the same or substantially the same composition, but the above configuration is also effective when the compositions of these liquids are different. That is, each liquid can be supplied and discharged independently, and mixing of the two is prevented.

[0159] Furthermore, the anode electrode 451 in the above embodiment is a soluble electrode that contains a metal (e.g., copper) that is the material of the plating film and is consumed as the plating process progresses. However, even in the case of a non-soluble electrode whose electrode material does not directly contribute to the plating reaction, problems such as uneven film thickness and film quality due to bias in current density distribution can occur. For this reason, even in the case of a non-soluble electrode, making it possible to individually adjust the current by using a divided structure as described above is effective in optimizing the current density distribution and achieving uniform film thickness.

[0160] As described above by way of example of specific embodiments, in the plating apparatus according to the present invention, for example, a porous membrane or an ion exchange resin membrane can be used as the electrolytic diaphragm. With such a configuration, it is possible to allow the movement of ions through the electrolytic diaphragm while preventing the passage of insoluble substances. Therefore, the plating process can be performed without causing anode slime to adhere to the substrate.

[0161] In addition, for example, a through hole serving as a discharge port may be provided in the side wall of the isolation tank at a position that is the lowest in the vertical direction when the isolation tank is in the inclined position, and the discharge unit may be configured to discharge liquid from this discharge port. With this configuration, when the isolation tank is in the inclined position, the liquid inside is guided toward the discharge port, and the liquid can be discharged more efficiently.

[0162] More specifically, for example, in the case where the isolation tank is formed in a rectangular shape in a plan view by four side walls that laterally surround the internal space, the outlet may be provided in one of the four side walls that is located at the lowest position in the vertical direction in the inclined posture. More preferably, if the outlet is provided in the lower part of the side wall, for example, at the connection part with the bottom, it is possible to drain the liquid without leaving it in the internal space.

[0163] For example, the plating apparatus may further include a supply source that delivers plating solution to the supply unit, and at least a portion of the piping connecting the supply source and the supply unit may be made of flexible piping. For example, the plating apparatus may further include a recovery unit that recovers the liquid discharged from the discharge port, and at least a portion of the piping connecting the discharge port and the recovery unit may be made of flexible piping. With these configurations, the isolation tank can be changed in position between a horizontal position and an inclined position without being hindered by the piping, and the flow through the piping is prevented from being hindered by such a change in position.

[0164] For example, in the present invention, the liquid supplied to the storage tank may have the same or substantially the same composition as the plating liquid stored in the treatment tank. Here, "substantially the same" refers to the main components being common and the basic chemical properties being roughly the same, and includes cases where there are slight differences in the content of each component, and cases where only the presence or absence, type, content, etc. of additives are different. With this configuration, the liquids separated by the electrolytic diaphragm can be considered to be substantially one body. This allows the desired plating treatment reaction to be achieved. [Industrial Applicability]

[0165] The present invention is suitable for use in a technique for forming a coating by plating one main surface of a substrate, and is particularly effective when a large rectangular substrate is to be processed. [Explanation of symbols]

[0166] 1. Plating equipment 2. Conveyor section 4. Plating section 41 Plating tank (treatment tank) 40,47 Chuck part (holding part) 400 Chuck mechanism (holding part) 412 Cathode Electrode 413,423 Lifting mechanism 450 Isolation tank (isolation section) 451 Anode Electrode 452 Frame (side wall) 453 Anode Electrode 46 Support mechanism (tilting mechanism) 47 Winch mechanism (tilt mechanism) 49 Plating solution supply and discharge section (supply source, recovery section) 491 Nozzle (supply section) L Plating solution (plating solution) L2 Plating solution (liquid) S-substrate Sa (of substrate S) top surface (one main surface)

Claims

1. A plating apparatus for plating at least one main surface of a flat substrate, comprising: A treatment tank for storing a plating solution; a holder that holds the substrate in a horizontal position with the one main surface facing upward in the processing tank; a cathode electrode in contact with a portion of the one main surface of the substrate held by the holding unit; an anode electrode disposed above the substrate held by the holder and facing the one main surface; a power supply unit connected to the anode electrode and the cathode electrode; an isolation section that surrounds the sides and bottom of the anode electrode to isolate the anode electrode from the plating solution in the treatment tank; Equipped with The isolating unit includes a box-shaped isolating tank having at least a bottom formed of an electrolytic diaphragm and accommodating the anode electrode in an internal space thereof; a tilting mechanism that switches the attitude of the isolation tank between a horizontal attitude in which the bottom is horizontal and an inclined attitude in which the bottom is inclined with respect to a horizontal plane; a supply unit that supplies a liquid to the internal space so as to immerse the anode electrode in the liquid; a discharge section that discharges the liquid from the isolation tank in the inclined position; The plating apparatus comprises:

2. 2. The plating apparatus according to claim 1, wherein the electrolytic diaphragm is a porous membrane or an ion exchange resin membrane.

3. A through hole serving as a discharge port is provided in a side wall of the isolation tank at a position that is the lowest in the up-down direction in the inclined posture, The plating apparatus according to claim 1 , wherein the discharge unit discharges the liquid from the discharge port.

4. 4. The plating apparatus according to claim 3, wherein the isolation tank is formed in a rectangular shape in a plan view by four side walls that laterally surround the internal space, and the discharge outlet is provided in one of the four side walls that has the lowest vertical position in the inclined posture.

5. a supply source for supplying the plating solution to the supply section; The plating apparatus according to claim 1 , wherein at least a portion of a pipe connecting the supply source and the supply unit is a flexible pipe.

6. a recovery section that recovers the liquid discharged from the discharge port, The plating apparatus according to claim 3 , wherein at least a portion of a pipe connecting said discharge port and said recovery section is a flexible pipe.

7. A plating method for plating at least one main surface of a flat substrate, comprising the steps of: holding the substrate in a horizontal position with the one main surface facing upward in a treatment tank that stores a plating solution; a step of bringing a cathode electrode into contact with a portion of the one main surface of the substrate held by the holding unit, while disposing an anode electrode above the substrate so as to face the one main surface; applying a voltage between the anode electrode and the cathode electrode; Equipped with The anode electrode is isolated from the plating solution by being surrounded laterally and downwardly by an isolation tank having at least a bottom portion made of an electrolytic diaphragm, and the voltage is applied to the anode electrode while the anode electrode is immersed in the liquid stored in the isolation tank; the plating method, after the application of the voltage is completed, changing the attitude of the isolation tank from a horizontal attitude to an inclined attitude, and discharging the liquid from a position on the side wall of the isolation tank that is the lowest in the vertical direction in the inclined attitude.

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