Plating apparatus and plating method

Abstract

To improve the uniformity of a plating film thickness in a plating apparatus for performing pulse plating.SOLUTION: A first plating tank configured to plate a substrate by applying a forward current and a reverse current pulse between the substrate and an anode, a first flow path connected to a reservoir tank and configured to discharge a plating solution from the reservoir tank, a second flow path connected to the first flow path and the first plating tank and configured to supply the plating solution to the first plating tank, A third flow path for returning the plating solution discharged from the reservoir tank to the reservoir tank by bypassing the first plating tank or discharging the plating solution to a discharge port, a first valve for adjusting a flow of the plating solution between the second flow path and the third flow path, and a control module for controlling the first valve according to a timing of a reverse current pulse during plating of the substrate to adjust the flow of the plating solution between the second flow path and the third flow path and reduce or stop supply of the plating solution to the second flow path as compared with a section of the forward current.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present application relates to a plating apparatus and a plating method. [Background technology]

[0002] Metal plating films such as Cu are formed on the surfaces of substrates for semiconductor devices and electronic elements. For example, electroplating may be performed by holding the substrate to be plated in a substrate holder and immersing the substrate together with the substrate holder in a plating tank containing a plating solution. The substrate holder holds the substrate so that the plating surface of the substrate is exposed. In the plating solution, an anode is positioned corresponding to the exposed surface of the substrate, and a voltage is applied between the substrate and the anode to pass a current, thereby forming an electroplating film on the exposed surface of the substrate.

[0003] For example, a photoresist layer having a plurality of openings is disposed on the surface of the substrate, and by plating the substrate with such a photoresist layer, bumps can be formed in the openings. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 7357824 specification [Patent Document 2] U.S. Patent No. 8,795,480 [Patent Document 3] US Patent No. 2023 / 0075605 Summary of the Invention [Problem to be solved by the invention]

[0005] The plating apparatus of Patent Document 1 applies at least one reverse current pulse to the substrate, flowing in the opposite direction to the forward current for depositing metal from the plating solution onto the substrate. This temporarily desorbs accelerator molecules from the plating film surface. During the subsequent period of supplying a forward current to the substrate, more accelerator molecules are adsorbed to areas with a low plating film formation rate (areas with small aperture diameters and / or high aperture density), thereby achieving uniform bump height (plating film thickness). The difference in the density of re-adsorbed accelerator molecules across locations is due to the fact that the degree to which desorbed accelerator molecules diffuse away from the plating film during the reverse current pulse period and current stop period differs depending on the location (i.e., aperture size and placement density). Therefore, the plating solution is agitated by a paddle during the current stop period or during the reverse current pulse and current stop period, or the agitation strength is reduced to suppress the diffusion of accelerator molecules desorbed by the reverse current pulse.

[0006] On the other hand, there are plating apparatuses such as those disclosed in Patent Document 2 that do not use paddles but instead generate a shear flow of the plating solution on the substrate surface to uniformly supply metal ions in the plating solution to the substrate surface, and those disclosed in Patent Document 3 that spray a jet of plating solution onto the substrate surface to uniformly supply metal ions in the plating solution to the substrate surface. Even in such plating apparatuses, it is preferable to achieve a uniform plating film thickness by utilizing the difference in density between accelerator molecules detached by a reverse current pulse and accelerator molecules reattached by a subsequent forward current.

[0007] The present invention aims to solve at least some of the above-mentioned problems, and one of the objects of the present invention is to improve the uniformity of plating film thickness in various types of plating apparatuses that perform pulse plating. [Means for solving the problem]

[0008] According to one aspect of the present invention, there is provided a plating apparatus comprising: a first plating tank that applies forward and reverse current pulses between a substrate and an anode to plate the substrate; a first flow path connected to a reservoir tank and for discharging plating solution from the reservoir tank; a second flow path connected to the first flow path and the first plating tank and for supplying plating solution to the first plating tank; a third flow path connected to the first flow path and for returning plating solution discharged from the reservoir tank to the reservoir tank by bypassing the first plating tank or for discharging the plating solution to an outlet; a first valve for regulating the flow of plating solution between the second flow path and the third flow path; and a control module that controls the first valve during plating of the substrate in accordance with the timing of the reverse current pulse to regulate the flow of plating solution between the second flow path and the third flow path and reduce or stop the supply of plating solution to the second flow path compared to the forward current section. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view showing the overall configuration of a plating apparatus according to an embodiment; [Figure 2] 1 is a plan view showing the overall configuration of a plating apparatus according to an embodiment; [Figure 3] FIG. 2 is a diagram schematically illustrating the peripheral configuration of one plating tank of a plating module according to an embodiment. [Figure 4] FIG. 2 is a schematic diagram showing bumps formed on a substrate. [Figure 5] 1 is a graph showing the time waveform of a plating current flowing between an anode and a substrate. [Figure 6] 1 is a graph showing the time waveform of a plating current flowing between an anode and a substrate. [Figure 7] 1A and 1B are conceptual diagrams illustrating the principle of improving the uniformity of the heights of a plurality of bumps. [Figure 8] FIG. 2 is a schematic diagram showing a fluid circuit for supplying a plating solution according to an embodiment. [Figure 9] 10 is a time chart of control for reducing or stopping the supply of plating solution in response to a reverse current pulse. [Figure 10] 10 is a time chart of control for reducing or stopping the supply of plating solution in response to a reverse current pulse. [Figure 11] FIG. 10 is a schematic diagram showing a fluid circuit for supplying a plating solution according to another embodiment. [Figure 12] FIG. 10 is a schematic diagram showing a fluid circuit for supplying a plating solution according to another embodiment. [Figure 13] FIG. 10 is a schematic diagram showing a fluid circuit for supplying a plating solution according to another embodiment. [Figure 14] FIG. 10 is a schematic diagram showing a fluid circuit for supplying a plating solution according to another embodiment. [Figure 15] FIG. 10 is a schematic diagram showing a fluid circuit for supplying a plating solution according to another embodiment. [Figure 16] FIG. 10 is a schematic diagram showing a fluid circuit for supplying a plating solution according to another embodiment. [Figure 17] FIG. 10 is a schematic diagram showing a fluid circuit for supplying a plating solution according to another embodiment. [Figure 18] FIG. 10 is a diagram schematically illustrating the peripheral configuration of a plating tank according to another embodiment. [Figure 19] FIG. 10 is a diagram schematically illustrating the peripheral configuration of a plating tank according to another embodiment.

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the drawings are diagrammatically illustrated to facilitate understanding of the features, and the dimensional ratios of the components may not be the same as those in reality. In addition, some drawings show XYZ Cartesian coordinates for reference. In these Cartesian coordinates, the Z direction corresponds to the upward direction, and the -Z direction corresponds to the downward direction (the direction in which gravity acts).

[0011] Fig. 1 is a perspective view showing the overall configuration of a plating apparatus 1000 of this embodiment. Fig. 2 is a plan view showing the overall configuration of the plating apparatus 1000 of this embodiment. As shown in Figs. 1 and 2, the plating apparatus 1000 includes a load port 100, a transfer robot 110, an aligner 120, a pre-wet module 200, a pre-soak module 300, a plating module 400, a cleaning module 500, a spin rinse dryer 600, a transfer device 700, and a control module 800.

[0012] The load port 100 is a module for loading substrates stored in a cassette such as a FOUP (not shown) into the plating apparatus 1000 and unloading substrates from the plating apparatus 1000 to the cassette. In this embodiment, four load ports 100 are arranged horizontally, but the number and arrangement of the load ports 100 are optional. The transfer robot 110 is a robot for transporting substrates and is configured to transfer substrates between the load ports 100, the aligner 120, the pre-wet module 200, and the spin rinse dryer 600. When transferring substrates between the transfer robot 110 and the transfer apparatus 700, the transfer robot 110 and the transfer apparatus 700 can transfer the substrates via a temporary stage (not shown).

[0013] The aligner 120 is a module for aligning the positions of the substrate's orientation flat, notch, and the like in a predetermined direction. In this embodiment, two aligners 120 are arranged horizontally, but the number and arrangement of the aligners 120 are arbitrary. The prewet module 200 wets the surface of the substrate to be plated with a treatment liquid such as pure water or degassed water before plating, thereby replacing air inside the pattern formed on the substrate surface with the treatment liquid. The prewet module 200 is configured to perform a prewet process that replaces the treatment liquid inside the pattern with a plating liquid during plating, making it easier to supply the plating liquid inside the pattern. In this embodiment, two prewet modules 200 are arranged vertically, but the number and arrangement of the prewet modules 200 are arbitrary.

[0014] The presoak module 300 is configured to perform a presoak process, which involves etching away, for example, an oxide film with high electrical resistance present on the surface of a seed layer formed on the surface of a substrate to be plated using a treatment solution such as sulfuric acid or hydrochloric acid, thereby cleaning or activating the surface of the substrate to be plated. In this embodiment, two presoak modules 300 are arranged vertically, but the number and arrangement of the presoak modules 300 are optional. The plating module 400 performs plating on the substrate. In this embodiment, two sets of 12 plating modules 400 are arranged vertically, three vertically and four horizontally, for a total of 24 plating modules 400, but the number and arrangement of the plating modules 400 are optional.

[0015] The cleaning module 500 is configured to perform a cleaning process on the substrate to remove plating solution and the like remaining on the substrate after plating. In this embodiment, two cleaning modules 500 are arranged vertically, but the number and arrangement of the cleaning modules 500 are optional. The spin rinse dryer 600 is a module for drying the substrate after cleaning by rotating it at high speed. In this embodiment, two spin rinse dryers 600 are arranged vertically, but the number and arrangement of the spin rinse dryers 600 are optional. The transport device 700 is a device for transporting substrates between multiple modules in the plating apparatus 1000. The control module 800 is configured to control the multiple modules of the plating apparatus 1000 and can be configured, for example, as a general computer or a dedicated computer equipped with an input / output interface with an operator.

[0016] An example of a series of plating processes performed by the plating apparatus 1000 will be described. First, a substrate stored in a cassette is loaded into the load port 100. Next, the transfer robot 110 removes the substrate from the cassette on the load port 100 and transfers the substrate to the aligner 120. The aligner 120 aligns the positions of the orientation flat, notch, etc. of the substrate to a predetermined direction. The transfer robot 110 delivers the substrate, whose direction has been aligned by the aligner 120, to the pre-wet module 200.

[0017] The pre-wet module 200 performs a pre-wet process on the substrate. The transfer device 700 transfers the substrate that has been subjected to the pre-wet process to the pre-soak module 300. The pre-soak module 300 performs a pre-soak process on the substrate. The transfer device 700 transfers the substrate that has been subjected to the pre-wet process to the pre-soak module 300. The processed substrate is transported to the plating module 400. The plating module 400 performs plating on the substrate.

[0018] The transfer device 700 transfers the plated substrate to the cleaning module 500. The cleaning module 500 performs a cleaning process on the substrate. The transfer device 700 transfers the cleaned substrate to the spin rinse dryer 600. The spin rinse dryer 600 dries the substrate. The transfer robot 110 receives the substrate from the spin rinse dryer 600 and transfers the dried substrate to a cassette on the load port 100. Finally, the cassette containing the substrate is removed from the load port 100.

[0019] It should be noted that the configuration of the plating apparatus 1000 described in FIGS. 1 and 2 is merely an example, and the configuration of the plating apparatus 1000 is not limited to the configurations shown in FIGS.

[0020] (Plating module) Next, a description will be given of the plating module 400. Since the multiple plating modules 400 included in the plating apparatus 1000 according to this embodiment have the same configuration, only one plating module 400 will be described.

[0021] FIG. 3 is a diagram illustrating the peripheral configuration of one plating tank 10 of a plating module 400 in a plating apparatus 1000 according to this embodiment. The plating module 400 according to this embodiment is a cup-type / horizontal plating apparatus in which a substrate is held in a horizontal position and plated. The plating module 400 of the plating apparatus 1000 according to this embodiment includes the plating tank 10, a substrate holder 20 for holding the substrate Wf, a rotation mechanism 22, and a lifting mechanism 24. The control module 800 described above includes a processor 801 and a non-transitory storage device 802. The storage device 802 stores programs, data, and the like. In the control module 800, the processor 801 controls the operation of the plating apparatus 1000 based on commands from the program stored in the storage device 802.

[0022] In this embodiment, one plating module 400 includes one plating tank 10 and one substrate holder. Two plating modules 400 (plating tank + substrate holder) may be connected to a common circulation pipe and reservoir tank (see FIG. 15, etc.).

[0023] As shown in FIG. 3, the plating tank 10 is configured as a bottomed container with an opening at the top. Specifically, the plating tank 10 has a bottom wall and an outer peripheral wall extending upward from the outer edge of the bottom wall, with the upper part of the outer peripheral wall being open. The shape of the outer peripheral wall of the plating tank 10 is not particularly limited, but the outer peripheral wall according to this embodiment has a cylindrical shape as an example. A plating solution is stored inside the plating tank 10. An overflow tank (not shown) is disposed outside the outer peripheral wall of the plating tank 10 to store plating solution that overflows from the upper end of the outer peripheral wall. The plating solution stored in the overflow tank is returned to a reservoir tank 410 (see FIG. 8, etc.) through a discharge port (not shown) of the overflow tank.

[0024] The plating solution may be any solution containing ions of the metal elements that make up the plating film, and specific examples thereof are not particularly limited. In this embodiment, copper plating is used as an example of plating, and a copper sulfate solution is used as an example of plating solution.

[0025] In this embodiment, the plating solution contains predetermined additives. The predetermined additives include, for example, an accelerator and an inhibitor. The accelerator may be, for example, a non-ionic additive. As such a non-ionic additive, SPS (bis(3-sulfopyrrolidone)) It is possible to use propyl disulfide, etc.

[0026] An anode 13 is disposed in an anode chamber 11 (described later) inside the plating tank 10. The anode 13 is disposed so as to extend horizontally. The specific type of the anode 13 is not particularly limited, and may be an insoluble anode or a soluble anode. In the present embodiment, an insoluble anode is used as an example of the anode 13. The specific type of the insoluble anode is not particularly limited, and platinum, iridium oxide, or the like may be used.

[0027] An ion resistor (distributor) 14 is disposed in a cathode chamber 12 (described later) inside the plating tank 10. Specifically, the ion resistor 14 is provided in the cathode chamber 12 above a diaphragm 40 (described later) and below the substrate Wf. The ion resistor 14 is a member that can resist the movement of ions in the cathode chamber 12, and is provided to homogenize the electric field formed between the anode 13 and the substrate Wf. The inclusion of the ion resistor 14 in the plating module 400 makes it possible to homogenize the thickness of the plating film (plating layer) formed on the substrate Wf.

[0028] The ionic resistor 14 according to this embodiment is configured by a plate member having a plurality of through holes formed so as to penetrate the upper and lower surfaces of the ionic resistor 14. The plurality of through holes are formed in a hole formation area of ​​the ionic resistor 14 (which in this embodiment is, for example, a circular area in top view). The specific material of the ionic resistor 14 is not particularly limited, but in this embodiment, for example, a resin such as polyether ether ketone is used.

[0029] A diaphragm 40 is disposed inside the plating tank 10. The interior of the plating tank 10 is divided by the diaphragm 40 into an anode chamber 11 below the diaphragm 40 and a cathode chamber 12 above the diaphragm 40. The anode 13 described above is disposed in the anode chamber 11, and the ion resistor 14 is disposed in the cathode chamber 12. During plating of a substrate, the substrate is disposed in the cathode chamber 12.

[0030] In this specification, the plating solution supplied to the anode chamber 11 may be referred to as the "anode solution," and the plating solution supplied to the cathode chamber may be referred to as the "cathode solution." Depending on the configuration of the plating tank, the anode chamber and the cathode chamber may not be separated (or may not be clearly distinguished), and the anode solution and the cathode solution may be referred to as the plating solution without distinction.

[0031] The diaphragm 40 is a membrane configured to allow ionic species (including metal ions) contained in the plating solution to pass through the diaphragm 40, while preventing additives contained in the plating solution from passing through the diaphragm 40. For example, an ion exchange membrane can be used as such a diaphragm 40.

[0032] As in the present embodiment, the plating module 400 is provided with the diaphragm 40, which can prevent the additives contained in the cathode solution in the cathode chamber 12 from migrating to the anode chamber 11. This can reduce the consumption of the additives in the cathode chamber 12.

[0033] The diaphragm 40 may have a cone shape ("V-shaped" in the cross section of FIG. 3), a disk shape that does not have any inclined portions and extends entirely horizontally, or any other shape.

[0034] The substrate holder 20 holds the substrate Wf as a cathode so that the surface to be plated (lower surface) of the substrate Wf faces the anode 13. The substrate holder 20 is connected to a rotation mechanism 22. The rotation mechanism 22 is a mechanism for rotating the substrate holder 20. The rotation mechanism 22 is connected to a lifting mechanism 24. The lifting mechanism 24 is supported by a support column 26 extending in the vertical direction. The lifting mechanism 24 is a mechanism for raising and lowering the substrate holder 20 and the rotation mechanism 22. The rotation mechanism 22 and the lifting mechanism 24 can be configured using known actuators such as motors. The operation of the rotation mechanism 22 and the lifting mechanism 24 is controlled by a control module 800. The substrate Wf and the anode 13 are electrically connected to a rectifier (power supply) 50. The power supply 50 is a device for passing electricity between the substrate Wf and the anode 13 when performing a plating process. The operation of the power supply 50 is controlled by the control module 800.

[0035] The plating tank 10 is provided with an anode chamber supply port (not shown) for supplying an anode solution (plating solution) to the anode chamber 11, and an anode chamber discharge port (not shown) for discharging the anode solution from the anode chamber 11. As an example, the anode chamber supply port may be located on the bottom wall of the plating tank 10, and the anode chamber discharge port may be located on the outer peripheral wall of the plating tank 10. As another example, the anode chamber discharge ports may be provided at multiple locations in the plating tank 10.

[0036] The plating tank 10 is also provided with a cathode liquid supply port 17A, a cathode liquid supply port 17B, and a cathode liquid drain port 17C. The cathode liquid supply port 17A is provided at one or more locations on the outer peripheral wall of the plating tank 10 below the ionic resistor 14. The cathode liquid (plating solution) supplied from the reservoir tank 410 (FIG. 4) via the cathode liquid supply port 17A is supplied from below to above through the multiple through-holes in the ionic resistor 14 onto the surface of the substrate Wf.

[0037] The cathode liquid supply port 17B is provided on the bottom surface of the outer peripheral wall of the plating tank 10, and is configured to supply the cathode liquid (plating solution) through a passage in the outer peripheral wall to a flow path between the substrate Wf and the ion resistor 14. The cathode liquid (plating solution) supplied from the reservoir tank 410 (see FIG. 8, etc.) to the flow path between the substrate Wf and the ion resistor 14 via the cathode liquid supply port 17B forms a horizontal flow of cathode liquid on the surface of the substrate Wf while shearing the cathode liquid (plating solution) passing from bottom to top through the ion resistor 14, and is then discharged from the cathode liquid drain port 17C. A slotted spacer (a spacer for forming a flow of plating solution) (not shown) that surrounds the periphery of the substrate in a plan view and opens on the cathode solution drain port 17C side is provided between the substrate Wf and the ion resistor 14, and this slotted spacer allows the cathode solution supplied from the cathode solution supply port 17A to form a flow of cathode solution over the entire surface of the substrate toward the cathode solution drain port 17C side.

[0038] The cathode fluid drain port 17C discharges the cathode fluid from the cathode chamber 12. The cathode fluid discharged from the cathode fluid drain port 17C is returned to the reservoir tank 410 via the overflow tank and its discharge port (not shown).

[0039] (bump) FIG. 4 is a schematic diagram showing bumps formed on a substrate by plating the surface of the substrate using a plating module 400. A thin metal seed layer 301 is formed on the entire surface of the substrate in advance, and power is supplied to the surface of the substrate through this seed layer 301 during plating. A photoresist layer 302 is formed on the seed layer 301, and the photoresist layer 302 has openings 302a where bumps will be formed. The substrate Wf on which the photoresist layer 302 is formed is held by the substrate holder 20 and immersed in the plating solution in the plating tank 10 for plating. During plating, the surface of the substrate Wf, except for the openings 302a in the photoresist layer 302, is shielded from the plating solution by the photoresist layer 302. As a result, a plating film grows only on the bottom surfaces of the openings 302a in the photoresist layer 302, forming bumps 303 on the substrate Wf. The photoresist layer 302 is removed after plating (see the right side of FIG. 4).

[0040] A large number of such bumps 303 are formed on the substrate Wf using a photoresist layer 302 with a predetermined opening pattern. Depending on the size and dimensions of the openings (i.e., the opening diameter) and the density of the openings (i.e., the number of openings per unit area), the height (film thickness) BH of the bumps 303 formed in each opening may vary, even on the same substrate. Therefore, it is required to form multiple bumps 303 on the substrate with a uniform height.

[0041] (Pulse plating current waveform) FIG. 5 is a graph showing the time waveform of the plating current output from the power supply 50 in the plating module 400 and flowing between the anode 13 and the substrate Wf. As shown in FIG. 5, the power supply 50 outputs a forward current during the first period T1. The "forward direction" refers to the direction in which the current flows through the plating solution from the anode 13 to the substrate Wf. Therefore, during the first period T1, metal ions in the plating solution are reduced on the surface to be plated of the substrate Wf, causing metal to deposit on the surface to be plated (i.e., a plating film is formed). The length of the first period T1 may be a length that occupies the majority of the total time during which the plating process is performed, so that the plating film substantially grows. In other words, the sum of the lengths of the second period T2 and the third period T3, which will be described later, may be negligible compared to the length of the first period T1. The magnitude of the forward current may be, for example, a constant current value I1 throughout the entire first period T1. Alternatively, the current value I1 of the forward current may be controlled to change over time.

[0042] During a second period T2, which is provided midway through the first period T1, the power supply 50 outputs a current in the opposite direction to the forward current. The current maintains a current value I2, which has a sign opposite to I1, during the second period T2. The length of the second period T2 is significantly shorter than the first period T1. Therefore, the current during the second period T2 is pulsed, which will be referred to herein as a "reverse current pulse." For example, the length of the second period T2, i.e., the pulse width of the reverse current pulse, may be approximately 0.1 seconds to several seconds. During the second period T2, in contrast to the reduction reaction of metal ions during the first period T1, some of the metal in the plating film formed on the surface to be plated during the first period T1 is redissolved in the plating solution, and the accelerator (one of the additives contained in the plating solution) that had adhered to the outermost surface of the plating film during the reduction reaction is detached from the plating film surface. Details will be described later.

[0043] It is desirable to set the current value I2 of the reverse current pulse to a value that will sufficiently desorb the accelerator. When the current value I2 is set equal to the current value I1, a power supply that outputs with a single polarity and a polarity reversal switch that can reverse the polarity of the power supply output may be used instead of the power supply 50 that outputs with both positive and negative polarities as described above.

[0044] Furthermore, during the third period T3 following the second period T2, the power supply 50 stops outputting current. That is, during the third period T3, current does not flow in either the forward or reverse direction through the plating solution. As with the second period T2, the length of the third period T3 is extremely short compared to the first period T1, and may be, for example, approximately 0.1 seconds to several seconds. As will be described in detail later, during the third period T3, the accelerator desorbed from the plating film surface diffuses within the plating solution.

[0045] After the third period T3, the power supply 50 again outputs a forward current (current value I1). The forward current continues until the predetermined plating processing time is completed, for example, until the thickness of the formed plating film reaches a predetermined target film thickness.

[0046] 5, the power supply 50 supplies one reverse current pulse in the middle of the first period T1 in which it outputs a forward current, and stops the current for a short period immediately after the reverse current pulse. The time position of the reverse current pulse (and the subsequent current stop) within the entire first period T1 is not particularly limited, but may be set to a value that is suitable for a plurality of bumps formed on a substrate. From the viewpoint of uniforming the height of 303, it is preferable that the reverse current pulse be initiated in the first half of the entire plating period. In addition, it is preferable to select the time position of the reverse current pulse so that the difference in the initial plating thickness depending on the location shown in Figure 7 can be compensated for and the plating thickness can be uniformed well.

[0047] As shown in FIG. 6, the supply of the reverse current pulse and the stopping of the current may be performed multiple times.

[0048] (Principle of improving bump height uniformity) 7 is a conceptual diagram illustrating the principle of improving the uniformity of the height of a plurality of bumps 303 by using the plating current shown in FIG. 5 or 6. On the surface of the substrate to be plated, the plating film formation rate is higher in areas where the diameter of the openings 302a in the photoresist layer 302 is large and where the arrangement density of the openings 302a is low, compared to other areas. This is because the smaller the diameter of the openings 302a and the higher the arrangement density of the openings 302a, the more difficult it is for metal ions to be sufficiently replenished in the openings 302a, resulting in a lower plating film formation rate. Therefore, during the first period T1 in which the forward current is supplied, before the second period T2 in which the reverse current pulse is supplied, Locations with large apertures and / or low aperture density The plating film thickness is Where openings are small and / or opening density is high The plating film thickness becomes thicker than that of the previous stage (stage (A) in FIG. 7).

[0049] As described above, the plating solution contains an accelerator as one of its additives, which has the effect of promoting the formation of a plating film. These accelerator molecules are concentrated and adsorbed at a constant density on the surface of the plating film regardless of location, accelerating the reduction reaction of metal ions. During the second period T2 in which the reverse current pulse is supplied, the accelerator molecules detach from the surface of the plating film and diffuse into and around the openings 302a. At this time, because the accelerator molecules are originally concentrated and adsorbed at a constant density on the surface of the plating film, the local concentration of the accelerator molecules detached from the surface of the plating film within each opening 302a is constant (stage (B) in FIG. 7).

[0050] However, in areas with a high opening density, similarly desorbed accelerator molecules are present in neighboring openings 302a, resulting in a small concentration gradient of accelerator molecules near these openings 302a. Therefore, relatively few of these accelerator molecules diffuse far away from the openings 302a, while many remain near the openings 302a. In contrast, in areas with a low opening density, the influence of neighboring openings 302a is small, resulting in a large concentration gradient of accelerator molecules near the openings 302a. Therefore, most of the accelerator molecules desorbed from the plating film diffuse far away, leaving only a small number remaining near the openings 302a. As a result, during the third period T3 during which no current flows through the plating solution, the average concentration of accelerator molecules near the openings 302a in areas with a high opening density is higher than that near the openings 302a in areas with a low opening density. In other words, differences in the opening density result in differences in the average concentration of accelerator molecules. In addition, differences in the size of the opening 302a also create similar differences in the concentration of accelerator molecules (if the opening diameter is large, the accelerator molecules tend to diffuse out of the opening 302a, so the concentration of accelerator molecules is lower near the opening 302a with a larger diameter).

[0051] Thus, the concentration of accelerator molecules near the openings 302a varies depending on the structure (i.e., size and arrangement density) of the openings 302a where the plating film is formed, and therefore, when a forward current is supplied again after the third period T3, the amount of accelerator molecules readsorbed onto the plating film surface in the openings 302a varies depending on the location. Specifically, the amount of accelerator molecules readsorbed is relatively small in locations where the opening diameter is large and / or the opening density is low, and the amount of accelerator molecules readsorbed is relatively large in locations where the opening diameter is small and / or the opening density is high (stage (C) in FIG. 7).

[0052] As described above, the accelerator desorption occurs uniformly (stage (B)). Therefore, when considering the overall process from desorption to re-adsorption, the density (or amount) of accelerator molecules re-adsorbed and present on the surface of the plating film is relatively small in the openings 302a located in areas with large opening diameters and / or low opening density, and relatively large in the openings 302a located in areas with small opening diameters and / or high opening density (stage (D) in FIG. 9). Therefore, the accelerator action is greater on the plating film surface in areas with small opening diameters and / or high opening density than in areas with large opening diameters and / or low opening density, resulting in an increased plating rate. This compensates for the difference in thickness of the plating film depending on the location (see stage (A)). As a result, the thickness of the plating film (i.e., bump 303) formed within the openings 302a is uniform, regardless of the structure of the openings 302a (stage (E) in FIG. 7).

[0053] As can be seen from the above explanation, in order to achieve uniform height of the bumps 303, it is important to create a difference in density of the accelerator molecules that are re-adsorbed after detachment depending on the location. As described above, this difference in density is due to the fact that the degree to which the detached accelerator molecules diffuse away from the plating film during the second period T2 and the third period T3 differs depending on the location (i.e., the size and arrangement density of the openings 302a). Therefore, if the flow of the plating solution on the substrate surface is strong during the second and third periods, the diffusion of the accelerator molecules is uniformed by the flow of the plating solution, thereby weakening the difference in density of the accelerator molecules that are re-adsorbed depending on the location. Therefore, to further improve the uniformity of the height of the bumps 303, it is preferable to weaken the flow of the plating solution on the substrate surface during the third period T3 or during both the second and third periods T2 and T3.

[0054] (Structure for improving bump height uniformity) 8 is a schematic diagram showing a fluid circuit for supplying a cathode fluid (plating solution) according to one embodiment. The fluid circuit for supplying an anode fluid (plating solution) will not be described here, but a conventional configuration can be used. The fluid circuit for supplying an anode fluid may be provided separately from the fluid circuit for supplying a cathode fluid, or they may share some or all of their configurations.

[0055] 8 includes a reservoir tank 410 that stores a cathode solution (plating solution), a flow path 411 connected to the reservoir tank 410 and used to discharge the cathode solution from the reservoir tank 410, a flow path 412 connected to the flow path 411 and the plating tank 10 and used to supply the cathode solution to the plating tank 10, a flow path 413 connected to the flow path 411 and used as a bypass flow path that returns the cathode solution discharged from the reservoir tank 410 to the reservoir tank 410, bypassing the plating tank 10, and a flow path adjustment mechanism 430 for adjusting the flow of the cathode solution between the flow path 412 and the flow path 413. The flow path 413 may also be referred to as the bypass flow path 413. The flow path 411 is provided with a pump 420 that serves as a circulation pump for pressure-feeding the cathode solution in the reservoir tank 410. Flow path 412 is provided with a flow meter 440 that detects the flow rate (volume of liquid passing through the cross section of the flow path per unit time) or flow velocity (flow rate per unit area) of the cathode solution supplied to plating tank 10. Note that flow meter 440 may be provided in flow path 413 to indirectly detect the flow rate of the cathode solution in flow path 412. Flow meter 440 may also be provided in both flow paths 412 and 413. Flow path 412 is connected to cathode solution supply ports 17A and 17B of plating tank 10 to supply the cathode solution (plating solution) to plating tank 10, and flow path 414 is connected to cathode solution drain port 17C of plating tank 10 to discharge the cathode solution from plating tank 10 and return it to reservoir tank 410.

[0056] In this specification, connection of flow paths includes a case where flow paths are directly connected to each other (or a flow path and a tank) and a case where flow paths are connected to each other (or a flow path and a tank) via another configuration (another flow path, component, etc.). Each flow path may include one or more pipes.

[0057] 8, the flow path adjustment mechanism 430 is a flow path switching valve that is connected to the flow paths 411, 412, and 413 and switches the flow path of the cathode fluid that flows downstream through the flow path 411 between the flow path 412 and the flow path 413. The flow path switching valve of the flow path adjustment mechanism 430 may be, for example, a three-way switching valve. Note that the flow path switching valve (three-way switching valve) may be one that completely blocks one flow path and switches the flow to the other flow path, or may be one that adjusts (decreases) the flow of liquid in one flow path while adjusting (increases) the flow of liquid in the other flow path.

[0058] The control module 800 is configured to control the flow path adjustment mechanism 430 in accordance with the timing of the reverse current pulse during plating of the substrate Wf, switch the flow of the cathode solution (plating solution) from the flow path 412 to the flow path 413, and stop the supply of the cathode solution to the flow path 412 (plating tank 10) during a period corresponding to the timing of the reverse current pulse (in this embodiment, during the third period T3, or the second period T2 and the third period T3) (FIG. 9). Note that "controlling the flow path adjustment mechanism in accordance with the timing of the reverse current pulse" means controlling the flow path adjustment mechanism in relation to the timing of the reverse current pulse, and includes cases where control is started earlier or later than the start of the reverse current pulse. The same applies to other embodiments.

[0059] The control module 800 can detect the second period T2 and the third period T3 (including predicting the arrival of the periods) based on the current command value output to the power supply 50. In one example, as shown in Fig. 9, during the third period T3 in which the current is stopped after the second period T2 of the reverse current pulse, the flow rate of the cathode solution (plating solution) supplied to the plating tank 10 via the flow path 412 is set to zero. In another example, the flow rate of the cathode solution (plating solution) supplied to the plating tank 10 may be set to zero during both the second period T2 and the third period T3.

[0060] This weakens the flow of plating solution on the surface of the substrate Wf during the period corresponding to the timing of the reverse current pulse (the third period T3, or the second and third periods T2 and T3), thereby preventing the accelerator molecules detached from the surface of the plating film on the substrate Wf from diffusing uniformly throughout the plating solution. As a result, the accelerator molecules are more likely to be re-adsorbed to compensate for differences in thickness of the plating film depending on the location on the substrate Wf, and the thickness of the plating film formed within the opening 302a (i.e., the height of the bump 303) can be made more uniform regardless of differences in the structure of the opening 302a.

[0061] In addition, during the period corresponding to the timing of the reverse current pulse (the third period T3, or the second period T2 and the third period T3), the flow rate of the cathode solution supplied to the plating tank 10 may be reduced below the flow rate f1 of the cathode solution during the first period T1. Reducing the flow rate of the plating solution (cathode solution) includes reducing the flow rate of the plating solution (cathode solution) to a value greater than zero or to zero. When there is no problem with both reducing and reducing the flow rate to zero, it may be expressed as "reducing or setting the flow rate of the plating solution (cathode solution) to zero."

[0062] At the end of the period corresponding to the timing of the reverse current pulse (the third period T3, or the second period T2 and the third period T3), the flow path adjustment mechanism 430 is returned to the state of the first period T1, and the flow rate of the cathode solution (plating solution) supplied to the plating tank 10 is returned to the flow rate of the first period T1.

[0063] As a result of detecting the flow rate of the cathode solution supplied to the plating tank 10 by the flow meter 440, if the timing at which the flow rate of the cathode solution supplied to the plating tank 10 is reduced is later than the desired timing (the start point of the third period T3 or the start point of the second period T2), as shown in FIG. 10, the flow rate of the cathode solution supplied to the plating tank 10 is reduced in the period corresponding to the timing of the next reverse current pulse (the third period T3 or the second and third periods). In order to reduce or eliminate the delay in the timing at which the flow rate of the flow channel adjustment mechanism 430 is reduced or eliminated, the flow channel adjustment mechanism 430 may be feedback-controlled to advance the timing at which the flow channel adjustment mechanism 430 is controlled. This feedback control can be implemented, for example, by the control module 800 comparing the target flow rate value of the cathode fluid with the detected flow rate value at the desired timing (the start point of the third period T3 or the start point of the second period T2) and adjusting the timing at which the flow channel adjustment mechanism 430 is controlled.

[0064] In one example, in the initial state, flow rate control is performed by the flow path adjustment mechanism 430 in accordance with the start of a period (the third period T3, or the second and third periods) corresponding to the timing of the reverse current pulse, and if the actual flow rate change is delayed, the timing of flow rate control by the flow path adjustment mechanism 430 (the timing at which the flow rate of the cathode solution supplied to the plating tank 10 is controlled to decrease) can be advanced so as to reduce or eliminate the delay.

[0065] On the other hand, if the timing at which the flow rate of the cathode solution supplied to the plating tank 10 starts to decrease is earlier than the desired timing (the start of the third period T3 or the start of the second period T2), the flow rate adjustment mechanism 430 may be feedback-controlled to delay the timing at which the flow rate adjustment mechanism 430 is controlled in order to reduce or eliminate the difference in the timing at which the flow rate of the cathode solution supplied to the plating tank 10 is decreased or zero in the period corresponding to the timing of the next reverse current pulse (the third period T3 or the second and third periods).

[0066] Another method for slowing or stopping the flow of plating solution on the substrate surface for a period corresponding to the timing of the reverse current pulse is to stop the circulation pump (pump 420). However, turning the circulation pump on and off is slow to respond to changes in the cathode solution flow rate, and it is considered difficult to slow or stop the flow of plating solution on the substrate surface for a predetermined period (0.1 seconds to several seconds) in accordance with the timing of the reverse current pulse I2. Therefore, in this embodiment, as described above, a bypass flow path 413 is provided that bypasses the plating tank 10, and the flow rate of plating solution supplied to the plating tank 10 is adjusted in accordance with the timing of the reverse current pulse I2.

[0067] (Another embodiment 1) FIG. 11 is a schematic diagram showing a fluid circuit for supplying a cathode solution (plating solution) according to another embodiment. In the above embodiment (FIG. 8), the cathode solution flowing into the flow path 413 is returned to the reservoir tank 410. However, as shown in FIG. 11, the downstream side of the flow path 413 may be connected to an outlet (not shown; hereinafter, also referred to as a plating module outlet) of the plating module 400, so that the cathode solution flowing into the flow path 413 is discharged from the outlet of the plating module 400 instead of being returned to the reservoir tank 410. Since the other configurations are the same as those of the embodiment of FIG. 8, detailed description thereof will be omitted. This configuration also achieves the same effects as those of the above embodiment. In the following embodiments, the bypass flow path 413 may also be connected to the plating module outlet.

[0068] (Another embodiment 2) FIG. 12 is a schematic diagram showing a fluid circuit for supplying a cathode solution (plating solution) according to another embodiment. As shown in FIG. 12, a flow path adjustment mechanism 430 may be provided on the flow path 412 to adjust the flow rate of the cathode solution supplied to the plating tank 10 to a reduced level or to zero during a period corresponding to the reverse current pulse (the third period T3, or the second and third periods T2 and T3). In this case, the flow path adjustment mechanism 430 may be a flow control valve or an on-off valve. The flow control valve is a valve that can adjust the flow rate to zero or a non-zero flow rate. The cathode solution corresponding to the reduction in the flow rate of the cathode solution through the flow path 412 by the flow path adjustment mechanism 430 flows into the bypass flow path 413, thereby enabling the flow rate of the cathode solution flowing through the flow path 412 (plating tank 10) to be adjusted quickly and accurately. Other configurations are similar to those of the embodiment shown in FIG. 8, and therefore detailed description thereof will be omitted.

[0069] (Other embodiment 3) FIG. 13 is a schematic diagram showing a fluid circuit for supplying a cathode solution (plating solution) according to another embodiment. As shown in FIG. 13, a flow path adjustment mechanism 430 may be provided on the bypass flow path 413 to adjust the flow rate of the cathode solution flowing through the bypass flow path 413 to increase the flow rate during a period corresponding to the reverse current pulse (the third period T3, or the second and third periods T2 and T3). This may indirectly adjust the flow rate of the cathode solution (plating solution) supplied to the plating tank 10 via the flow path 412 to decrease or eliminate the flow rate. In this case, the flow path adjustment mechanism 430 may be a flow control valve or an on-off valve. The flow path adjustment mechanism 430 can reduce the flow rate of the cathode solution flowing through the flow path 412 by the amount corresponding to the increase in the flow rate of the cathode solution flowing through the flow path 413. This allows the flow rate of the cathode solution flowing through the flow path 412 (plating tank 10) to be adjusted quickly and accurately. Other configurations are similar to those of the embodiment shown in FIG. 8, and therefore detailed description thereof will be omitted.

[0070] (Other embodiment 4) 14 is a schematic diagram showing a fluid circuit for supplying a cathode solution (plating solution) according to another embodiment. As shown in FIG. 14, the flow path adjustment mechanism 430 may be configured to include a flow path adjustment mechanism 431 provided in the flow path 412 and a flow path adjustment mechanism 432 provided in the bypass flow path 413. That is, the flow paths may be switched (the flow rate of the cathode solution flowing through the flow path 412 may be set to zero) or the flow rate of the cathode solution flowing through the flow path 412 may be reduced (including set to zero) by simultaneously operating the flow path adjustment mechanisms 431 and 432.

[0071] The flow path adjustment mechanism 431 can be a flow control valve or an on-off valve. The flow path adjustment mechanism 432 can be a flow control valve or an on-off valve. The flow path adjustment mechanism 431 and the flow path adjustment mechanism 432 can also be different types of valves. FIG. 14 illustrates a case where both the flow path adjustment mechanism 431 and the flow path adjustment mechanism 432 are on-off valves. The other configurations are the same as those in the embodiment of FIG. 8, so detailed description will be omitted.

[0072] According to this embodiment, the cathode fluid corresponding to the amount of the flow rate of the cathode fluid flowing through the flow path 412 reduced by the flow path adjustment mechanism 431 flows through the bypass flow path 413, so that the flow rate of the cathode fluid flowing through the flow path 412 can be adjusted quickly and accurately.

[0073] (Other embodiment 5) FIG. 15 is a schematic diagram showing a fluid circuit for supplying a cathode solution according to another embodiment. In this embodiment, the cathode solution is supplied to two plating tanks 10-1 and 10-2 via a flow path 412. As shown in FIG. 15, the flow path 412 branches into flow paths 412-1 and 412-2 downstream, with the flow path 412-1 connected to the plating tank 10-1 and the flow path 412-2 connected to the plating tank 10-2. Although not shown in FIG. 15, the flow path adjustment mechanism 430 can have any of the configurations described above. That is, a flow path adjustment mechanism 430 having any of the configurations described above is provided to adjust the flow path (flow rate) between the flow path 412 (before branching) and the flow path 413.

[0074] Similarly to the above, the flow path adjustment mechanism 430 is controlled by the control module 800 to increase the flow rate of the cathode solution flowing through the bypass flow path 413 so as to reduce or eliminate the flow rate of the cathode solution flowing through the flow path 412 during a period (the third period T3, or the second period T2 and the third period T3) corresponding to the timing of the reverse current pulse I2. This reduces or eliminates the flow rate of the cathode solution supplied to the two plating tanks 10-1 and 10-2 via the flow path 412 during a period corresponding to the timing of the reverse current pulse. In this configuration, the bypass flow path 413 is connected to the flow path 411 (and the flow path 412) before the flow path 412 branches toward each of the plating tanks 10-1 and 10-2. Therefore, the flow rates of the cathode solution supplied to the plating tanks 10-1 and 10-2 can be simultaneously controlled by the single common bypass flow path 413. This configuration is suitable for pulse plating in which the current is changed at the same timing in the two plating tanks 10-1 and 10-2.

[0075] 15, the flow meter 440 may be provided in each of the flow paths 412-1 and 412-2. Alternatively, the flow meter 440 may be provided in the flow path 412 before the branching, and half of the flow rate detected by the flow meter 440 may be detected as the flow rate supplied to each plating tank 10.

[0076] The configuration of FIG. 15 may be applied to three or more plating tanks. (Other embodiment 6)

[0077] 16 is a schematic diagram showing a fluid circuit for supplying a cathode solution according to another embodiment. In this embodiment, a flow path 411 branches into a flow path 411-1 and a flow path 411-2. The flow path 411-1 branches into a flow path 412-1 and a flow path (bypass flow path) 413-1. The flow path 412-1 is connected to the plating tank 10-1, and the flow path 413-1 returns the cathode solution to the reservoir tank 410 or discharges it to the outlet of the plating module 400. The flow path 411-2 branches into a flow path 412-2 and a flow path (bypass flow path) 413-2. The flow path 412-2 is connected to the plating tank 10-2, and the flow path 413-2 returns the cathode solution to the reservoir tank 410 or discharges it to the outlet of the plating module 400.

[0078] The flow path adjustment between the flow path 412-1 connected to the plating tank 10-1 and the bypass flow path 413-1, and the flow path adjustment between the flow path 412-2 connected to the plating tank 10-2 and the bypass flow path 413-2 can be performed using any of the above-described configurations of the flow path adjustment mechanism 430. In this case, the flow path 412-1 and the bypass flow path 413-1 correspond to the flow path 412 and the bypass flow path 413, respectively, in the above-described embodiment, and the flow path adjustment mechanism 430 may be disposed in the flow path 411-1, the flow path 412-1, and / or the flow path 413-1. Furthermore, the flow path 412-2 and the bypass flow path 413-2 correspond to the flow path 412 and the bypass flow path 413, respectively, in the above-described embodiment, and the flow path adjustment mechanism 430 may be disposed in the flow path 411-2, the flow path 412-2, and / or the flow path 413-2.

[0079] In this configuration, the flow path adjustment mechanism 430 is configured to use any of the above-described configurations and be controlled by the control module 800 in the same manner as described above, so as to increase the flow rate of the cathode solution flowing through the flow path 413-1 so as to reduce or eliminate the flow rate of the cathode solution flowing through the flow path 412-1 (the flow rate of the cathode solution into the plating tank 10-1) in accordance with the timing of the reverse current pulse (during the third period T3, or the second period T2 and the third period T3). Furthermore, the flow path adjustment mechanism 430 is configured to use any of the above-described configurations and be controlled by the control module 800 in the same manner as described above, so as to increase the flow rate of the cathode solution flowing through the flow path 413-2 in accordance with the timing of the reverse current pulse (during the third period T3, or the second period T2 and the third period T3) so as to reduce or eliminate the flow rate of the cathode solution flowing through the flow path 412-2 (the flow rate of the cathode solution into the plating tank 10-2).

[0080] According to this configuration, the bypass flow paths 413-1 and 413-2 are connected after the flow path 411 branches toward each of the plating tanks 10-1 and 10-2. Therefore, even if the timing of the reverse current pulses in the plating tanks 10-1 and 10-2 is different, the flow rate of the cathode solution supplied to each of the plating tanks 10-1 and 10-2 can be individually controlled according to the timing of the reverse current pulses in each of the plating tanks 10-1 and 10-2. The flow rates of the cathode solution supplied to each of the plating tanks 10-1 and 10-2 are detected by flow meters 440-1 and 440-2. The flow meter 440-1 can be provided in the flow path 412-1 and / or the flow path 413-1. The flow meter 440-2 can be provided in the flow path 412-2 and / or the flow path 413-2. do.

[0081] 17 may be applied to three or more plating tanks. In this case, the downstream configuration of the flow path 411: (411-1, 412-1, 413-1), (411-2, 412-2, 413-2), ... may be provided for each plating tank.

[0082] (Other embodiment 7) FIG. 17 is a schematic diagram showing a fluid circuit for supplying a cathode solution (plating solution) according to another embodiment. In this embodiment, a flow path 411 branches into flow paths 412a and 412b, and the flow paths 412a and 412b are connected to a flow path 412 downstream. The flow paths 412a and 412b have different flow path areas (flow path diameter / piping diameter). A flow path adjustment mechanism 430a and a flow path adjustment mechanism 430b are disposed in the flow paths 412a and 412b, respectively. The flow path adjustment mechanism 430a may be a flow control valve or an on-off valve. The flow path adjustment mechanism 430b may be a flow control valve or an on-off valve. The flow path adjustment mechanism 430a and the flow path adjustment mechanism 430b may be different types of valves.

[0083] In one example, both the flow path adjustment mechanism 430a and the flow path adjustment mechanism 430b can be on-off valves. Since the flow paths 412a and 412b have different flow path areas (pipe diameters), the flow rate of the cathode solution supplied to the plating tank 10 can be changed by controlling the on-off valves (flow path adjustment mechanism 430a, flow path adjustment mechanism 430b) on the flow paths 412a and 412b, depending on which flow path area the cathode solution is passed through. For example, when the flow path area Sa of the flow path 412a is larger than the flow path area Sb of the flow path 412b (Sa > Sb), the cathode solution is supplied to the plating tank 10 through the flow path 412a during the supply of a forward current, and is supplied to the plating tank 10 through the flow path 412b depending on the timing of the reverse current pulse (during the third period T3, or the second and third periods T2 and T3). This allows the flow rate of the catholyte supplied to the plating tank 10 to be reduced in accordance with the timing of the reverse current pulse.

[0084] The flow rate of the cathode solution supplied to the plating tank 10 may be changed (decreased) by controlling the flow path adjustment mechanism 430a and the flow path adjustment mechanism 430b to change the ratio of the cathode solution flowing through the flow paths 412a and 412b. For example, when the flow path area Sa of the flow path 412a is larger than the flow path area Sb of the flow path 412b (Sa>Sb), the flow path adjustment mechanism 430a and the flow path adjustment mechanism 430b are controlled to decrease the ratio of the cathode solution flowing through the flow path 412a and increase the ratio of the cathode solution flowing through the flow path 412b, in accordance with the timing of the reverse current pulse, compared to when a forward current is supplied (first period T1). In this way, the total flow rate of the cathode solution (plating solution) flowing through the flow paths 412a and 412b toward the plating tank 10 can be decreased in accordance with the timing of the reverse current pulse (in the third period T3, or the second and third periods T2 and T3) compared to when a forward current is supplied (first period T1).

[0085] A flow meter 440 may be provided in the flow path 412 after the junction of the flow paths 412a and 412b to monitor changes in the flow rate of the catholyte supplied to the plating tank 10 (FIGS. 9 and 10). Feedback control may be performed to adjust the timing of controlling the flow path adjustment mechanisms 430a and 430b (the timing at which the flow rate of the catholyte supplied to the plating tank 10 is reduced) so that the catholyte flow rate changes at the desired timing (the third period T3, or the second period T2 and the third period T3) in response to the reverse current pulse (FIG. 9). The flow meter 440 may be provided in the flow paths 412a, 412b, and / or 412. For example, the flow meter 440 may be provided in the flow paths 412a and 412b, and the flow rate of the catholyte supplied to the plating tank 10 may be obtained from the sum of the detected values ​​of the flow meters.

[0086] The flow path 412 may be configured to join the flow paths 412a and 412b. The flow path 12a and the flow path 412b may be directly connected to the catholyte supply port 17A. The same applies to the catholyte supply port 17B.

[0087] In FIG. 17, the above-mentioned bypass flow path 413 may be provided upstream of the flow paths 412a and 412b.

[0088] The configuration of FIG. 17 can also be applied to a configuration including two or more plating tanks, as illustrated in FIGS. 15 and 16. For example, in FIGS. 15 and 16, flow path 412-1 can be branched into two flow paths, similar to flow paths 412a and 412b in FIG. 17, with each flow path provided with a flow path adjustment mechanism. Also, flow path 412-2 can be branched into two flow paths, similar to flow paths 412a and 412b in FIG. 17, with each flow path provided with a flow path adjustment mechanism. In this case, in FIGS. 15 and 16, the flow path adjustment mechanism (FIGS. 8, 11-14) that adjusts the flow rate can be omitted by using bypass flow paths 413, 413-1, and 413-2. Also, in FIGS. 15 and 16, bypass flow paths 413, 413-1, and 413-2 may be omitted.

[0089] (Other embodiment 8) The fluid circuit configuration of the above-described embodiment (including other embodiments 1 to 7) is not limited to the plating module of the type (cup type / horizontal type) shown in Figure 3, but can be applied to any type of plating module including a dip type / vertical type. Figure 18 is a diagram schematically showing the peripheral configuration of the plating tank 10 of a plating module 400 according to another embodiment.

[0090] The plating tank 10 (plating module 400) according to this embodiment is a dip-type / vertical plating tank (plating module) in which a substrate Wf held by a substrate holder 20 is immersed in a plating solution in an upright position. In the plating tank 10, an anode 13 is held by an anode holder 30 and positioned upright facing the substrate Wf. A distributor 80 is disposed between the substrate Wf and the anode 13. The distributor 80 is configured to supply plating solution to the substrate Wf and is provided with one or more through-holes extending from the anode 13 side to the substrate Wf side and one or more injection holes for injecting plating solution supplied from the outside via a plating solution supply port 17D toward the substrate Wf. The distributor 80 is configured to receive plating solution via the plating solution supply port 17D and inject the plating solution toward the substrate Wf from one or more injection holes. By spraying the plating solution onto the substrate Wf from the injection holes of the distributor 80, a flow of plating solution is formed on the surface of the substrate Wf, thereby uniformly supplying metal ions to the substrate surface. The configuration for spraying the plating solution onto the substrate Wf is not limited to the configuration shown in Fig. 18, and any configuration can be adopted. Similar to the plating tank described above (Fig. 3), a forward current I1 and a reverse current pulse I2 (Figs. 9 and 10) are supplied from the power source 50 between the substrate Wf and the anode 13, so that the substrate Wf is pulse-plated.

[0091] In the plating tank 10 of Figure 18, by adopting a configuration in which the supply flow rate of plating solution to the plating tank 10 (distributor 80) is reduced or set to zero during the period corresponding to the reverse current pulse (the third period T3, or the second period T2 and the third period T3) as described above, the plating film thickness (bump height) can be made more uniform regardless of the location on the substrate Wf.

[0092] (Other embodiment 9) 19 is a diagram schematically illustrating the peripheral configuration of a plating tank 10 according to another embodiment. In the above-described embodiment, the flow rate of the plating solution supplied to the plating tank 10 is reduced or set to zero in accordance with the timing of the reverse current pulse, thereby weakening the flow of the plating solution on the substrate surface. In this embodiment, however, the flow of the plating solution on the substrate surface is weakened by raising the substrate holder 20 to increase the flow path area between the substrate Wf and the ion resistor 14.

[0093] Specifically, the control module 800 controls the lifting mechanism 24 in response to the reverse current pulse to raise the substrate holder 20 so that the height of the substrate holder 20 is higher during the third period T3 or the second and third periods T2 and T3 than when a forward current is supplied. This increases the flow path area between the substrate Wf and the ion resistor 14 compared to when a forward current is supplied, thereby weakening the flow of plating solution on the substrate surface. In this configuration, the height of the substrate holder 20 is controlled to reach a target value (higher than the height of the substrate holder 20 when a forward current is supplied) during the period corresponding to the reverse current pulse (the third period T3 or the second and third periods T2 and T3). The height of the substrate holder 20 can be detected, for example, by detecting the drive amount of an actuator (such as a known motor) that drives the lifting mechanism 24. A sensor (such as an optical sensor) for detecting the height of the substrate holder 20 may be provided separately.

[0094] If the height of the substrate holder 20 is detected and the timing of the change in height (higher change) of the substrate holder 20 is delayed from the desired timing (the start of the third period T3 or the start of the second period T2), the lifting mechanism 24 may be feedback-controlled to advance the timing of controlling the lifting mechanism 24 in a period corresponding to the timing of the next reverse current pulse (the third period T3 or the second and third periods) in order to reduce or eliminate the delay in the timing of the change in height of the substrate holder 20. This feedback control can be implemented, for example, by the control module 800 comparing the height detection value with a target height value of the substrate holder 20 at the desired timing (the start of the third period T3 or the start of the second period T2) and adjusting the timing of controlling the lifting mechanism 24.

[0095] In one example, in the initial state, the height of the substrate holder 20 is changed by the lifting mechanism 24 to coincide with the start of the period corresponding to the timing of the reverse current pulse (the third period T3, or the second and third periods), and if there is a delay in the change in the height of the substrate holder 20, the timing of the lifting mechanism 24 changing the height of the substrate holder 20 can be advanced so as to reduce or eliminate the delay.

[0096] On the other hand, if the timing of the change in height (to increase) of the substrate holder 20 is earlier than the desired timing (the start of the third period T3 or the start of the second period T2), the lifting mechanism 24 may be feedback-controlled to delay the timing of controlling the lifting mechanism 24 (the timing of control to increase the height of the substrate holder 20) in order to reduce or eliminate the timing difference in the change in height of the substrate holder 20 in the period corresponding to the timing of the next reverse current pulse (the third period T3, or the second and third periods).

[0097] In addition, the flow of plating solution on the substrate surface may be weakened by combining the configuration in which the supply flow rate of plating solution to the plating tank is reduced or set to zero in accordance with the timing of the reverse current pulse (including other embodiments 1 to 8) with control in which the substrate holder is raised in accordance with the timing of the reverse current pulse to increase the flow area between the substrate and the ion resistor (other embodiment 9).

[0098] (Other embodiment 10) The configurations according to the above-described embodiments (including other embodiments 1 to 9) are applicable to plating devices for plating circular substrates such as wafers, polygonal substrates such as square substrates, and substrates of any other shape.

[0099] The present invention can also be described as the following aspects. [1] According to one embodiment, a first plating tank for plating a substrate by applying a forward current pulse and a reverse current pulse between the substrate and an anode, a first flow path connected to a reservoir tank for discharging a plating solution from the reservoir tank, and a first plating tank for discharging a plating solution from the reservoir tank. a second flow path connected to a reservoir tank and supplying plating solution to the first plating tank; a third flow path connected to the first flow path and returning plating solution discharged from the reservoir tank to the reservoir tank by bypassing the first plating tank or discharging it to an outlet; a first valve for regulating the flow of plating solution between the second flow path and the third flow path; and a control module for controlling the first valve according to the timing of a reverse current pulse during plating of the substrate to regulate the flow of plating solution between the second flow path and the third flow path and to reduce or stop the supply of plating solution to the second flow path compared to the section of forward current. The first valve may be provided on the first flow path or the second flow path, or may be connected to the first flow path, the second flow path, and the third flow path. "Controlling the first valve in accordance with the timing of the reverse current pulse" means controlling the first valve in relation to the timing of the reverse current pulse, and includes cases where control is started earlier or later than the timing of the reverse current pulse.

[0100] According to this embodiment, by adjusting the flow rates of the plating solution flowing through the second and third flow paths according to the timing of the reverse current pulse, the flow rate of the plating solution supplied to the plating tank (first plating tank) is reduced to less than that during the forward current period or set to zero. This allows the flow rate of the plating solution supplied to the plating tank to be quickly reduced or set to zero during a period according to the timing of the reverse current pulse (during a current stop period following the reverse current pulse supply period, or during the reverse current pulse supply period and the current stop period), thereby weakening the flow of the plating solution on the substrate surface. This prevents accelerator molecules detached from the plating film surface from diffusing into the plating solution during the reverse current pulse supply period and / or the current stop period. More accelerator molecules are retained on the plating film surface in areas of the photoresist layer with smaller opening diameters and / or higher opening density than in areas with larger opening diameters and / or lower opening density, allowing more accelerator molecules to be redeposited when the forward current is supplied. This compensates for plating rates that vary depending on the opening size and / or arrangement density of the photoresist layer openings, and makes it possible to make the height of bumps formed in the photoresist layer openings uniform regardless of the location on the substrate.

[0101] Furthermore, since the flow rate is adjusted between the two flow paths (the second and third flow paths), the flow rate (amount supplied per unit time) of the plating solution supplied to the plating tank can be quickly reduced.

[0102] [2] According to one embodiment, the first valve includes a flow path switching valve connected to the first flow path, the second flow path, and the third flow path, and switching the flow paths between the second flow path and the third flow path.

[0103] According to this embodiment, the flow rate of the plating solution flowing through the second and third flow paths can be quickly adjusted by the flow path switching valve.

[0104] [3] According to one embodiment, the flow path switching valve is a three-way valve.

[0105] According to this embodiment, the flow rates of the plating solutions flowing through the second and third flow paths can be quickly adjusted with a simple configuration.

[0106] [4] According to one embodiment, the first valve is provided in the second flow path.

[0107] According to this embodiment, the flow rate of the plating solution flowing through the second flow path can be directly adjusted, and the flow rates of the plating solutions flowing through the second and third flow paths can be quickly adjusted with a simple configuration.

[0108] [5] According to one embodiment, the first valve is provided in the third flow path.

[0109] According to this embodiment, the flow rate of the plating solution flowing through the second flow path is indirectly adjusted by adjusting the flow rate of the plating solution flowing through the third flow path, thereby enabling the flow rates of the plating solutions flowing through the second and third flow paths to be quickly adjusted with a simple configuration.

[0110] [6] According to one embodiment, the device further comprises a second valve, wherein the first valve is provided in the second flow path, and the second valve is provided in the third flow path, and the first valve and the second valve are controlled by the control module to operate at the same timing.

[0111] According to this embodiment, the first and second flow path adjustment devices provided in the second and third flow paths can more accurately adjust the flow rates of the plating solution flowing through the second and third flow paths even when the flow path resistances (piping resistances) of the second and third flow paths are different.

[0112] [7] According to one embodiment, the first valve includes at least one of a flow control valve and an on-off valve.

[0113] According to this aspect, the flow rate of the plating solution flowing through the second and third flow paths can be quickly adjusted with a simple configuration using the flow rate control valve or the on-off valve.

[0114] [8] According to one embodiment, the plating system further comprises a second plating tank and a fourth flow path branching from the second flow path to the second plating tank, and the control module controls the first valve according to the timing of the reverse current pulse during plating of the substrate to reduce or stop the supply of plating solution to the first and second plating tanks compared to the forward current section.

[0115] According to this embodiment, the flow rates of the plating solutions to the first and second plating tanks can be controlled by using the common (single) third flow path as a bypass flow path.

[0116] [9] According to one embodiment, the plating apparatus further comprises: a second plating tank; a fourth flow path branching from the first flow path to the second plating tank upstream of the point where the third flow path is connected to the first flow path; a fifth flow path connected to the fourth flow path and returning plating solution discharged from the reservoir tank to the reservoir tank by bypassing the second plating tank or discharging it to an outlet; and a third valve for regulating the flow of plating solution between the fourth flow path and the fifth flow path, wherein the control module further controls the third valve during plating of the substrate in accordance with the timing of a reverse current pulse to regulate the flow of plating solution between the fourth flow path and the fifth flow path, and reduces or stops the supply of plating solution to the fourth flow path compared to the section of forward current.

[0117] According to this embodiment, even if the timing of the reverse current pulses in the first plating tank and the second plating tank is different, the flow rates of the plating solution to the first plating tank and the second plating tank can be controlled individually.

[0118]

[10] According to one embodiment, the plating apparatus further includes a flow meter for detecting the flow rate of the plating solution in the second flow path, and when the control module determines, based on the flow rate detected by the flow meter, that the timing at which the flow rate of the plating solution in the second flow path decreases deviates from the desired timing corresponding to the timing of the reverse current pulse, the control module performs feedback control of the timing to control the first valve so as to reduce the timing deviation.

[0119] According to this embodiment, the flow rate of the plating solution can be changed with more accurate timing, thereby weakening the flow of the plating solution on the substrate surface.

[0120]

[11] According to one embodiment, there is provided a plating apparatus comprising: a plating tank that applies forward and reverse current pulses between a substrate and an anode to plate the substrate; a first flow path connected to a reservoir tank and for discharging a plating solution from the reservoir tank; a second flow path and a third flow path fluidly connected to the first flow path and the plating tank and arranged in parallel to each other, the second flow path having a larger inner diameter than the third flow path; a first valve provided in the second flow path; a second valve provided in the third flow path; and a control module configured to control the first and second valves in accordance with timing of a reverse current pulse during plating of the substrate, thereby adjusting the flow of plating solution between the second flow path and the third flow path and reducing the total flow rate of plating solution through the second and third flow paths to be lower than that in a forward current section. "Reducing the total flow rate of the plating solution through the second flow path and the third flow path to be lower than that in the section of forward current" includes cases where no plating solution is flowed through the second flow path and the plating solution is flowed through the third flow path.

[0121] According to this embodiment, the flow rate of the plating solution into the first plating tank can be quickly controlled by controlling the flow of the plating solution between the second and third flow paths with different flow path areas in accordance with the timing of the reverse current pulse.

[0122]

[12] According to one embodiment, the plating system further includes one or more flow meters that detect a total flow rate of the plating solution through the second flow path and the third flow path, and when the control module determines, based on the flow rates detected by the one or more flow meters, that the timing at which the total flow rate of the plating solution through the second flow path and the third flow path decreases deviates from a desired timing corresponding to the timing of the reverse current pulse, the control module feedback controls the timing of controlling the first valve and the second valve so as to reduce the timing deviation.

[0123] According to this embodiment, the flow rate of the plating solution can be changed with more accurate timing, thereby weakening the flow of the plating solution on the substrate surface.

[0124]

[13] According to one aspect, a plating bath; an anode disposed in the plating bath; a substrate holder that holds a substrate so as to face the anode; a resistor that is disposed between the substrate holder and the anode and has a plurality of through holes that form a flow path for a plating solution; a lifting device that lifts and lowers the substrate holder; a power supply that applies forward current and reverse current pulses between the substrate and the anode; and a control module, wherein the plating tank is configured to supply plating solution to the substrate via the resistor and also supply plating solution along the surface of the substrate so as to shear the plating solution supplied to the substrate via the resistor, and the control module is configured to control the lifting device to lift the substrate holder according to the timing of the reverse current pulse during plating of the substrate, thereby increasing the flow area of ​​the plating solution between the substrate and the resistor and weakening the flow of plating solution on the substrate surface compared to the forward current section.

[0125] According to this aspect, the flow of the plating solution on the substrate surface can be weakened by raising the substrate holder in accordance with the timing of the reverse current pulse.

[0126]

[14] According to one embodiment, the control module acquires the height of the substrate holder, and if it determines based on the acquired height of the substrate holder that the timing at which the height of the substrate holder rises deviates from the desired timing corresponding to the timing of the reverse current pulse, it feedback controls the timing at which the lifting device is controlled so as to reduce the timing deviation.

[0127] According to this embodiment, the flow of the plating solution on the substrate surface can be weakened with more accurate timing.

[0128]

[15] According to one embodiment, there is provided a method for plating a substrate by applying forward and reverse current pulses between a substrate and an anode in a plating tank, the method comprising: preparing a plating apparatus including a plating tank; a first flow path connected to a reservoir tank for discharging plating solution from the reservoir tank; a second flow path connected to the first flow path and the plating tank for supplying plating solution to the plating tank; a third flow path connected to the first flow path for returning plating solution discharged from the reservoir tank to the reservoir tank by bypassing the plating tank or for discharging the plating solution to an outlet; and a first valve for regulating the flow of plating solution between the second flow path and the third flow path; and controlling the first valve according to the timing of the reverse current pulse during plating of the substrate to reduce or stop the supply of plating solution to the second flow path compared to the forward current section.

[0129]

[16] According to one embodiment, there is provided a method for plating a substrate by applying forward and reverse current pulses between the substrate and an anode in a plating tank, the method comprising: preparing a plating apparatus including: a plating tank; a first flow path connected to a reservoir tank for discharging a plating solution from the reservoir tank; a second flow path and a third flow path fluidly connected to the first flow path and the plating tank and arranged in parallel to each other, the second flow path having a larger inner diameter than the third flow path; a first valve provided in the second flow path; and a second valve provided in the third flow path; and controlling the first and second valves according to timing of the reverse current pulse during plating of the substrate to adjust the flow of plating solution between the second flow path and the third flow path, thereby reducing the total flow rate of the plating solution flowing through the second and third flow paths to be lower than that in the forward current section.

[0130]

[17] According to one embodiment, there is provided a method for plating a substrate by applying forward and reverse current pulses between a substrate and an anode in a plating tank, the method comprising: preparing a plating apparatus including a plating tank, an anode disposed in the plating tank, a substrate holder that holds the substrate so as to face the anode, a resistor disposed between the substrate holder and the anode and forming a flow path for plating solution between the substrate and the anode, and an elevating device that raises and lowers the substrate holder, wherein the plating tank is configured to supply plating solution to the substrate through the resistor and to supply the plating solution along the surface of the substrate so as to shear the plating solution supplied to the substrate through the resistor; and controlling the elevating device to raise the substrate holder according to the timing of the reverse current pulse during plating of the substrate, thereby widening the flow path area for plating solution between the substrate and the resistor and weakening the flow of plating solution on the surface of the substrate compared to the section of forward current.

[0131]

[18] According to one embodiment, a plating apparatus includes a plating tank, a first flow path connected to a reservoir tank for discharging plating solution from the reservoir tank, a second flow path connected to the first flow path and the plating tank for supplying plating solution to the plating tank, a third flow path connected to the first flow path for returning plating solution discharged from the reservoir tank to the reservoir tank by bypassing the plating tank or discharging the plating solution to an outlet, and a first valve for regulating the flow of plating solution between the second flow path and the third flow path. The plating apparatus further includes a storage medium having stored thereon a program for causing a computer to execute a control method for plating a substrate by applying forward and reverse current pulses between a substrate and an anode, the storage medium storing thereon a program for causing a computer to execute the control method: during plating of the substrate, control the first valve in accordance with the timing of the reverse current pulse to regulate the flow of plating solution between the second flow path and the third flow path, and reduce or stop the supply of plating solution to the second flow path to a level lower than that in the forward current section.

[0132]

[19] According to one embodiment, there is provided a storage medium storing a program for causing a computer to execute a control method for plating a substrate by applying forward and reverse current pulses between a substrate and an anode in a plating apparatus including: a plating tank; a first flow path connected to a reservoir tank and for discharging a plating solution from the reservoir tank; second and third flow paths fluidly connected to the first flow path and the plating tank and arranged in parallel to each other, wherein the inner diameter of the second flow path is larger than the inner diameter of the third flow path; a first valve provided in the second flow path; and a second valve provided in the third flow path. The storage medium stores a program for causing a computer to execute the control method for plating a substrate by applying forward and reverse current pulses between the substrate and an anode, the storage medium storing the program for causing a computer to execute the control method: during plating of the substrate, controlling the first and second valves in accordance with timing of the reverse current pulse to adjust the flow of plating solution between the second and third flow paths and to reduce the total flow rate of plating solution flowing through the second and third flow paths to be lower than that in a forward current section.

[0133]

[20] According to one embodiment, there is provided a storage medium storing a program for causing a computer to execute a control method for plating a substrate by applying forward and reverse current pulses between the substrate and the anode in a plating apparatus comprising: a plating tank; an anode disposed in the plating tank; a substrate holder that holds a substrate opposite the anode; a resistor disposed between the substrate holder and the anode and having a plurality of through holes that form a flow path for a plating solution; and an elevator that raises and lowers the substrate holder, wherein the plating tank is configured to supply the plating solution to the substrate through the resistor and to supply the plating solution along the surface of the substrate so as to shear the plating solution supplied to the substrate through the resistor. The storage medium stores a program for causing a computer to execute the control method for plating the substrate by applying forward and reverse current pulses between the substrate and the anode, wherein the storage medium stores a program for causing a computer to execute the control method for controlling the elevator to raise the substrate holder in accordance with the timing of the reverse current pulse during plating of the substrate, thereby widening the flow path area for the plating solution between the substrate and the resistor and weakening the flow of the plating solution on the surface of the substrate compared to the forward current section.

[0134] Although the embodiments of the present invention have been described above, the above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The present invention may be modified or improved without departing from the spirit thereof, and the present invention naturally includes equivalents thereof. Furthermore, any combination of the embodiments and modifications is possible within the scope of solving at least part of the above-described problems or achieving at least part of the effects, and any combination or omission of the components described in the claims and specification is possible.

[0135] The entire disclosures of US Patent No. 7357824 (Patent Document 1), US Patent No. 8795480 (Patent Document 2), and US Patent No. 2023 / 0075605 (Patent Document 3), including the specifications, claims, drawings, and abstracts, are incorporated herein by reference in their entirety. [Explanation of symbols]

[0136] 10 Plating tank 11 Anode chamber 12 Cathode chamber 13 Anode 14 Ion resistor 17A, 17B Catholyte supply port 17C Catholyte drain port 17D Plating solution supply port 20 Substrate holder 22 Rotation mechanism 24 Lifting mechanism 26 Posts 30 Anode holder 40 Diaphragm 50 Rectifier (power supply) 80 distributor 400 plating modules 411 Flow path 412 Flow path 413 Bypass flow path 414 Flow path 420 Pump 430 Flow path adjustment mechanism 440 Flow meter 800 Control Module 801 processor 802 Storage device 1000 plating equipment Wf substrate

Claims

1. a first plating tank for plating the substrate by applying forward and reverse current pulses between the substrate and an anode; a first flow path connected to the reservoir tank for discharging the plating solution from the reservoir tank; a second flow path connected to the first flow path and the first plating tank, for supplying a plating solution to the first plating tank; a third flow path connected to the first flow path, for returning the plating solution discharged from the reservoir tank to the reservoir tank while bypassing the first plating tank, or for discharging the plating solution to a discharge port; a first valve for regulating the flow of plating solution between the second flow path and the third flow path; a control module that controls the first valve to adjust the flow of plating solution between the second flow path and the third flow path in accordance with the timing of a reverse current pulse during plating of the substrate, thereby reducing or stopping the supply of plating solution to the second flow path compared to the period of a forward current; A plating apparatus comprising:

2. 2. The plating apparatus according to claim 1, The plating apparatus, wherein the first valve includes a flow path switching valve connected to the first flow path, the second flow path, and the third flow path, and switching the flow paths between the second flow path and the third flow path.

3. 3. The plating apparatus according to claim 2, The plating apparatus, wherein the flow path switching valve is a three-way valve.

4. 2. The plating apparatus according to claim 1, The plating apparatus, wherein the first valve is provided in the second flow path.

5. 2. The plating apparatus according to claim 1, The plating apparatus, wherein the first valve is provided in the third flow path.

6. 2. The plating apparatus according to claim 1, Further comprising a second valve; the first valve is provided in the second flow path, the second valve is provided in the third flow path, The plating apparatus, wherein the first valve and the second valve are controlled by the control module so as to operate at the same timing.

7. 7. The plating apparatus according to claim 4, The plating apparatus, wherein the first valve includes at least one of a flow control valve and an on-off valve.

8. 2. The plating apparatus according to claim 1, a second plating tank; a fourth flow path branching from the second flow path to the second plating tank; The control module controls the first valve according to the timing of the reverse current pulse during plating of the substrate to reduce or stop the supply of plating solution to the first and second plating tanks compared to the period of the forward current. Plating equipment.

9. 2. The plating apparatus according to claim 1, a second plating tank; The third flow path is connected to the first flow path upstream of the point where the third flow path is connected to the first flow path. a fourth flow path branching into the plating tank; a fifth flow path connected to the fourth flow path, for returning the plating solution discharged from the reservoir tank to the reservoir tank while bypassing the second plating tank, or for discharging the plating solution to a discharge port; a third valve for adjusting the flow of the plating solution between the fourth flow path and the fifth flow path; Further provided with The control module further controls the third valve during plating of the substrate in accordance with the timing of the reverse current pulse to adjust the flow of plating solution between the fourth flow path and the fifth flow path, and reduces or stops the supply of plating solution to the fourth flow path compared to the section of forward current.

10. 2. The plating apparatus according to claim 1, a flow meter for detecting a flow rate of the plating solution in the second flow path; When the control module determines, based on the flow rate detected by the flow meter, that the timing at which the flow rate of the plating solution in the second flow path decreases deviates from the desired timing corresponding to the timing of the reverse current pulse, the control module feedback-controls the timing at which the first valve is controlled so as to reduce the timing deviation.

11. a plating tank for plating the substrate by applying forward and reverse current pulses between the substrate and an anode; a first flow path connected to the reservoir tank for discharging the plating solution from the reservoir tank; a second flow path and a third flow path fluidly connected to the first flow path and the plating tank and arranged in parallel with each other, wherein an inner diameter of the second flow path is larger than an inner diameter of the third flow path; a first valve provided in the second flow path; a second valve provided in the third flow path; a control module configured to control the first valve and the second valve in response to timing of a reverse current pulse during plating of the substrate to adjust the flow of plating solution between the second flow path and the third flow path so that the total flow rate of plating solution through the second flow path and the third flow path is reduced compared to that during a period of forward current; A plating apparatus comprising:

12. 12. The plating apparatus according to claim 11, one or more flow meters for detecting a total flow rate of the plating solution through the second flow path and the third flow path; When the control module determines, based on the flow rate detected by the one or more flow meters, that the timing at which the total flow rate of the plating solution through the second flow path and the third flow path decreases deviates from a desired timing corresponding to the timing of the reverse current pulse, the control module feedback-controls the timing at which the first valve and the second valve are controlled so as to reduce the timing deviation.

13. A plating tank; an anode disposed in the plating tank; a substrate holder that holds a substrate so as to face the anode; a resistor disposed between the substrate holder and the anode, the resistor having a plurality of through holes that form a flow path for the plating solution; a lifting device that lifts and lowers the substrate holder; a power supply that applies forward and reverse current pulses between the substrate and the anode; A control module; Equipped with the plating tank is configured to supply a plating solution to the substrate via the resistor and to supply the plating solution along a surface of the substrate so as to shear the plating solution supplied to the substrate via the resistor; The control module is configured to control the lifting device to lift the substrate holder in accordance with the timing of the reverse current pulse during plating of the substrate, thereby widening the flow area of ​​the plating solution between the substrate and the resistor and weakening the flow of the plating solution on the surface of the substrate compared to the section of the forward current. A plating apparatus comprising:

14. 14. The plating apparatus according to claim 13, The control module acquires the height of the substrate holder, and when it determines, based on the acquired height of the substrate holder, that the timing at which the height of the substrate holder rises deviates from the desired timing corresponding to the timing of the reverse current pulse, it performs feedback control on the timing of controlling the lifting device so as to reduce the timing deviation.

15. 1. A method for plating a substrate by applying forward and reverse current pulses between the substrate and an anode in a plating tank, comprising: a plating apparatus including a plating tank, a first flow path connected to a reservoir tank for discharging a plating solution from the reservoir tank, a second flow path connected to the first flow path and the plating tank for supplying a plating solution to the plating tank, a third flow path connected to the first flow path for returning the plating solution discharged from the reservoir tank to the reservoir tank by bypassing the plating tank or for discharging the plating solution to an outlet, and a first valve for adjusting the flow of the plating solution between the second flow path and the third flow path; During plating of the substrate, the first valve is controlled in accordance with the timing of a reverse current pulse to reduce or stop the supply of plating solution to the second flow path compared to the forward current section.

16. 1. A method for plating a substrate by applying forward and reverse current pulses between the substrate and an anode in a plating tank, comprising: a plating apparatus including a plating tank, a first flow path connected to a reservoir tank for discharging a plating solution from the reservoir tank, a second flow path and a third flow path fluidly connected to the first flow path and the plating tank and arranged in parallel with each other, the second flow path having a larger inner diameter than the third flow path, a first valve provided in the second flow path, and a second valve provided in the third flow path; During plating of the substrate, the first valve and the second valve are controlled in accordance with the timing of a reverse current pulse to adjust the flow of plating solution between the second flow path and the third flow path, thereby reducing the total flow rate of plating solution flowing through the second flow path and the third flow path compared to the period during which the current is forward.

17. 1. A method for plating a substrate by applying forward and reverse current pulses between the substrate and an anode in a plating tank, comprising: a plating apparatus including a plating tank, an anode disposed in the plating tank, a substrate holder that holds a substrate facing the anode, a resistor disposed between the substrate holder and the anode and that forms a flow path for plating solution between the substrate and the resistor, and an elevating device that elevates the substrate holder, wherein the plating tank is configured to supply plating solution to the substrate via the resistor and to supply plating solution along the surface of the substrate so as to shear the plating solution supplied to the substrate via the resistor; During plating of the substrate, the lifting device is controlled to raise the substrate holder in accordance with the timing of the reverse current pulse, widening the flow area of ​​the plating solution between the substrate and the resistor, and The method further comprises weakening the flow of plating solution on the substrate surface to be weaker than in the section of forward current.

18. a first flow path connected to a reservoir tank for discharging plating solution from the reservoir tank; a second flow path connected to the first flow path and the plating tank for supplying plating solution to the plating tank; a third flow path connected to the first flow path for returning plating solution discharged from the reservoir tank to the reservoir tank by bypassing the plating tank or for discharging the plating solution to an outlet; and a first valve for regulating the flow of plating solution between the second flow path and the third flow path, the storage medium storing a program for causing a computer to execute a control method for plating a substrate by applying forward and reverse current pulses between the substrate and an anode, During plating of the substrate, controlling the first valve in accordance with timing of a reverse current pulse to adjust the flow of plating solution between the second flow path and the third flow path, and reducing or stopping the supply of plating solution to the second flow path compared to a section of forward current; A storage medium that stores a program for causing a computer to execute the above.

19. a first flow path connected to a reservoir tank for discharging a plating solution from the reservoir tank; a second flow path and a third flow path fluidly connected to the first flow path and the plating tank and arranged in parallel with each other, the second flow path having a larger inner diameter than the third flow path; a first valve provided in the second flow path; and a second valve provided in the third flow path. The plating apparatus includes a storage medium having stored therein a program for causing a computer to execute a control method for plating a substrate by applying forward and reverse current pulses between the substrate and an anode, A storage medium storing a program for causing a computer to execute the following: during plating of the substrate, controlling the first valve and the second valve in accordance with timing of a reverse current pulse to adjust the flow of plating solution between the second flow path and the third flow path, and reducing the total flow rate of plating solution flowing through the second flow path and the third flow path to be lower than in a section of forward current.

20. a storage medium storing a program for causing a computer to execute a control method for plating a substrate by applying forward and reverse current pulses between the substrate and the anode in a plating apparatus comprising: a plating tank; an anode disposed in the plating tank; a substrate holder that holds a substrate so as to face the anode; a resistor disposed between the substrate holder and the anode and having a plurality of through holes that form a flow path for a plating solution; and an elevating device that elevates the substrate holder, wherein the plating tank is configured to supply the plating solution to the substrate via the resistor and to supply the plating solution along the surface of the substrate so as to shear the plating solution supplied to the substrate via the resistor, During plating of the substrate, controlling the lifting device to lift the substrate holder in accordance with the timing of a reverse current pulse, thereby widening the flow area of ​​the plating solution between the substrate and the resistor, and weakening the flow of the plating solution on the substrate surface compared to the section of the forward current; A storage medium that stores a program for causing a computer to execute the above.

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