Plating apparatus and method for removing bubbles

Abstract

The present invention relates to a plating apparatus and a method for removing bubbles. The present invention provides a technique capable of removing bubbles remaining in a resistor. The plating apparatus (1000) includes: a plating tank (10) that stores a plating solution (Ps) and has a resistor (12) disposed therein; a substrate holder (30) that is disposed above the resistor and holds a dummy substrate (Wfx); a rotation mechanism (40) that rotates the substrate holder; and a lifting mechanism (50) that raises and lowers the substrate holder. At least one convex portion (60) that protrudes downward from the lower surface is provided on the lower surface of the dummy substrate. The substrate holder has a ring (31) that protrudes downward from the outer peripheral edge of the lower surface of the dummy substrate. The lower surface of the convex portion is located below the lower surface of the ring. The plating apparatus is configured such that, in a state where the lifting mechanism lowers the substrate holder so that the convex portion of the dummy substrate is located above the resistor and the convex portion of the dummy substrate is immersed in the plating solution in the plating tank, the rotation mechanism rotates the substrate holder.

Description

Technical Field

[0001] The present invention relates to a plating apparatus and a method for removing bubbles. Background Art

[0002] Conventionally, as a plating apparatus capable of performing a plating process on a substrate, a so-called cup-type plating apparatus is known (for example, refer to Patent Document 1). Such a plating apparatus includes: a plating bath for storing a plating solution; a substrate holder for holding the substrate as a cathode; a rotation mechanism for rotating the substrate holder; and a lifting mechanism for lifting and lowering the substrate holder.

[0003] In addition, conventionally, for example, the following technique is known: in order to achieve in-plane uniformity of the film thickness of a coating film, a porous resistor is disposed inside the plating bath (for example, refer to Patent Document 2).

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2008-19496

[0005] Patent Document 2: Japanese Patent Application Laid-Open No. 2004-363422

[0006] In the cup-type plating apparatus exemplified in Patent Document 1 above, when the resistor exemplified in Patent Document 2 is disposed inside the plating bath, for example, bubbles contained in the plating solution in the plating bath may stay in the resistor (specifically, the lower surface of the resistor and the holes of the resistor). When performing a plating process on the substrate in a state where bubbles stay in the resistor, there is a concern that the plating quality of the substrate may deteriorate due to the staying bubbles. Summary of the Invention

[0007] The present invention has been made in view of the above circumstances, and one of its objects is to provide a technique capable of removing bubbles staying in a resistor.

[0008] (Aspect 1)

[0009] In order to achieve the above object, a plating apparatus according to one aspect of the present invention includes: a plating tank that stores a plating solution and has a porous resistor disposed therein; a substrate holder that is disposed above the resistor and holds a dummy substrate; a rotation mechanism that rotates the substrate holder; and a lifting mechanism that raises and lowers the substrate holder. At least one convex portion that protrudes downward from the lower surface of the dummy substrate is provided on the lower surface of the dummy substrate. The substrate holder has a ring that protrudes downward from the outer peripheral edge of the lower surface of the dummy substrate. The lower surface of the convex portion is located below the lower surface of the ring. The plating apparatus is configured such that, in a state where the lifting mechanism lowers the substrate holder so that the convex portion of the dummy substrate is located above the resistor and the convex portion is immersed in the plating solution in the plating tank, the rotation mechanism rotates the substrate holder.

[0010] According to this aspect, when the convex portion of the dummy substrate immersed in the plating solution rotates, the pressure difference generated around the convex portion of the dummy substrate can be used to suck up the bubbles on the lower surface of the resistor and inside the holes. Thereby, the bubbles remaining in the resistor can be removed.

[0011] (Aspect 2)

[0012] In the above Aspect 1, a space may be provided between the convex portion and the ring so that the convex portion does not contact the ring.

[0013] (Aspect 3)

[0014] In the above Aspect 1 or 2, the protruding height of the convex portion protruding from the lower surface of the dummy substrate may also be a value selected from the range of 1 mm or more and 100 mm or less.

[0015] According to this aspect, it is possible to suppress the difficulty in transporting the dummy substrate due to the excessive protruding height of the convex portion, and to suppress the reduction in the bubble removal effect of the dummy substrate due to the too low protruding height of the convex portion. That is, it is possible to ensure the ease of transporting the dummy substrate and to sufficiently remove the bubbles remaining in the resistor.

[0016] (Aspect 4)

[0017] In any of the above Aspects 1 to 3, the convex portion may also extend in the radial direction of the lower surface of the dummy substrate.

[0018] (Aspect 5)

[0019] In the above Aspect 4, the convex portion may also have a bent portion that bends in the circumferential direction of the dummy substrate at at least a part of the convex portion.

[0020] (Aspect 6)

[0021] In any one of the above-described Modes 1 to 3, the convex portion may also have: a first portion that extends along the radial direction of the lower surface of the dummy substrate from the center of the lower surface of the dummy substrate toward the outer peripheral edge of the lower surface of the dummy substrate; and a second portion that is connected to the end portion on the outer peripheral edge side of the first portion and is inclined with respect to the first portion.

[0022] (Mode 7)

[0023] In any one of the above-described Modes 1 to 3, when the lower surface of the dummy substrate is divided by a plurality of imaginary concentric circles, at least one of the convex portions may be disposed in each of the regions divided by the plurality of imaginary concentric circles.

[0024] (Mode 8)

[0025] In any one of the above-described Modes 1 to 7, the substrate holder may be configured to hold the substrate during a plating process for plating the substrate, and hold the dummy substrate during bubble removal for removing bubbles remaining in the resistor body. The lifting mechanism may position the substrate holder at a position higher than that during the plating process during the bubble removal.

[0026] According to this mode, during bubble removal, it is possible to easily prevent the convex portion of the dummy substrate from contacting the resistor body.

[0027] (Mode 9)

[0028] In any one of the above-described Modes 1 to 8, when the convex portion of the dummy substrate is immersed in the plating solution in the plating tank, the lifting mechanism may also immerse the portion of the lower surface of the dummy substrate where the convex portion is not provided in the plating solution in the plating tank.

[0029] According to this mode, compared with the case where the portion of the lower surface of the dummy substrate where the convex portion is not provided is not immersed in the plating solution, it is possible to suppress fluctuations in the liquid level of the plating solution in the plating tank when the substrate holder rotates and the convex portion rotates. Thereby, it is possible to suppress liquid splashing of the plating solution in the plating tank.

[0030] (Mode 10)

[0031] In order to achieve the above object, a bubble removal method according to one aspect of the present invention is a bubble removal method for removing bubbles trapped in a resistor body in a plating bath. The plating bath stores a plating solution and has the porous resistor body disposed therein. The bubble removal method includes: holding a dummy substrate having a lower surface provided with at least one convex portion protruding downward by a substrate holder; lowering the substrate holder holding the dummy substrate, and immersing the convex portion in the plating solution in the plating bath in a state where the convex portion is located above the resistor body; and rotating the substrate holder in a state where the convex portion of the dummy substrate is located above the resistor body and the convex portion is immersed in the plating solution in the plating bath. The substrate holder has a ring protruding downward from an outer peripheral edge of the lower surface of the dummy substrate, and a lower surface of the convex portion is located below a lower surface of the ring.

[0032] According to this aspect, it is possible to remove bubbles trapped in the resistor body. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a perspective view showing an overall structure of a plating apparatus according to an embodiment.

[0034] Figure 2 is a top view showing an overall structure of a plating apparatus according to an embodiment.

[0035] Figure 3 is a schematic view showing a structure of a plating module of a plating apparatus according to an embodiment.

[0036] Figure 4 is a schematic cross-sectional view showing a state where a dummy substrate is immersed in a plating solution during bubble removal according to an embodiment.

[0037] Figure 5 is a cross-sectional view schematically showing a state where a substrate holder holds a substrate as a cathode according to an embodiment.

[0038] Figure 6 is a schematic bottom view of a dummy substrate according to an embodiment.

[0039] Figure 7 is a flowchart showing an example of a bubble removal method according to an embodiment.

[0040] Figure 8 is a schematic cross-sectional view magnifying a part of a peripheral structure of a convex portion during bubble removal of a plating apparatus according to Modification 1 of an embodiment.

[0041] Figure 9 is a schematic bottom view of a dummy substrate according to Modification 2 of an embodiment.

[0042] Figure 10 It is a schematic bottom view of a dummy substrate related to Modification Example 3 of the embodiment.

[0043] Figure 11 It is a schematic bottom view of a dummy substrate related to Modification Example 4 of the embodiment.

[0044] Figure 12 It is a schematic bottom view of a dummy substrate related to Modification Example 5 of the embodiment.

[0045] Figure 13 It is a schematic bottom view of a dummy substrate related to Modification Example 6 of the embodiment.

[0046] Figure 14 It is a schematic bottom view of a dummy substrate related to Modification Example 7 of the embodiment.

[0047] Figure 15 It is a schematic cross-sectional view of the peripheral structure of the plating bath of the plating apparatus related to Modification Example 8 of the embodiment. Detailed Embodiment

[0048] (Embodiment)

[0049] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in the following embodiments and modification examples of the embodiments, the same or corresponding structures are often denoted by the same reference numerals and description is appropriately omitted. Further, the drawings are schematically illustrated for easy understanding of the features of the constituent elements, and the dimensional ratios of the constituent elements are not limited to the same as the actual ones. In addition, in several drawings, an X-Y-Z orthogonal coordinate is illustrated for reference. In this orthogonal coordinate, the Z direction corresponds to the upper side, and the -Z direction corresponds to the lower side (the direction of gravity).

[0050] Figure 1 It is a perspective view showing the overall structure of the plating apparatus 1000 of the present embodiment. Figure 2 It is a top view showing the overall structure of the plating apparatus 1000 of the present embodiment. As Figure 1 and Figure 2 shown, the plating apparatus 1000 includes a loading port 100, a transfer robot arm 110, an aligner 120, a pre-wetting module 200, a pre-dipping module 300, a plating module 400, a cleaning module 500, a rotary rinsing and drying module 600, a transfer device 700, and a control module 800.

[0051] The loading port 100 is a module for loading a substrate housed in a cassette such as a FOUP (not shown) into the plating apparatus 1000 or unloading the substrate from the plating apparatus 1000 to the cassette. In the present embodiment, four loading ports 100 are arranged in a horizontal direction, but the number and arrangement of the loading ports 100 are arbitrary. The transfer robot arm 110 is a robot arm for transferring the substrate, and is configured to transfer the substrate between the loading port 100, the aligner 120, and the transfer device 700. When the transfer robot arm 110 and the transfer device 700 transfer the substrate between them, the transfer robot arm 110 and the transfer device 700 can transfer the substrate via a temporary placement table (not shown).

[0052] The aligner 120 is a module for aligning the positions of the orientation plane, notch, etc. of the substrate with a specified direction. In the present embodiment, two aligners 120 are arranged in a horizontal direction, but the number and arrangement of the aligners 120 are arbitrary. The pre-wetting module 200 replaces the air inside the pattern formed on the substrate surface with a treatment liquid by wetting the surface to be plated of the substrate before the plating treatment with a treatment liquid such as pure water or degassed water. The pre-wetting module 200 is configured to perform a pre-wetting treatment that facilitates the supply of the plating liquid into the pattern by replacing the treatment liquid inside the pattern with the plating liquid during plating. In the present embodiment, two pre-wetting modules 200 are arranged in a vertical direction, but the number and arrangement of the pre-wetting modules 200 are arbitrary.

[0053] The pre-dipping module 300 is configured to perform, for example, a pre-dipping treatment of etching and removing a resistive oxide film existing on the surface of the seed layer formed on the surface to be plated of the substrate before the plating treatment with a treatment liquid such as sulfuric acid or hydrochloric acid to clean or activate the surface of the plating substrate. In the present embodiment, two pre-dipping modules 300 are arranged in a vertical direction, but the number and arrangement of the pre-dipping modules 300 are arbitrary. The plating module 400 performs a plating treatment on the substrate. In the present embodiment, there are two sets of a component of twelve plating modules 400 arranged in three in the vertical direction and four in the horizontal direction, and a total of 24 plating modules 400 are provided, but the number and arrangement of the plating modules 400 are arbitrary.

[0054] The cleaning module 500 is configured to perform a cleaning process on the substrate in order to remove the plating solution and the like remaining on the substrate after the plating process. In the present embodiment, two cleaning modules 500 are arranged in the vertical direction, but the number and arrangement of the cleaning modules 500 are arbitrary. The rotary rinsing and drying module 600 is a module for drying the substrate by rotating it at high speed after the cleaning process. In the present embodiment, two rotary rinsing and drying modules 600 are arranged in the vertical direction, but the number and arrangement of the rotary rinsing and drying modules 600 are arbitrary. The conveying device 700 is a device for conveying the substrate between a plurality of modules in the plating apparatus 1000. The control module 800 is configured to control a plurality of modules of the plating apparatus 1000 and can be constituted by, for example, a general computer or a dedicated computer having an input / output interface with the operator.

[0055] An example of a series of plating processes performed on the plating apparatus 1000 will be described. First, the substrate housed in the cassette is carried into the loading port 100. Next, the transfer robot 110 takes out the substrate from the cassette at the loading port 100 and conveys the substrate to the aligner 120. The aligner 120 aligns the position of the orientation plane, notch, etc. of the substrate with a specified direction. The transfer robot 110 transfers the substrate whose direction has been aligned by the aligner 120 to the conveying device 700.

[0056] The conveying device 700 conveys the substrate received from the transfer robot 110 to the pre-wetting module 200. The pre-wetting module 200 performs a pre-wetting process on the substrate. The conveying device 700 conveys the substrate on which the pre-wetting process has been performed to the pre-dipping module 300. The pre-dipping module 300 performs a pre-dipping process on the substrate. The conveying device 700 conveys the substrate on which the pre-dipping process has been performed to the plating module 400. The plating module 400 performs a plating process on the substrate.

[0057] The conveying device 700 conveys the substrate on which the plating process has been performed to the cleaning module 500. The cleaning module 500 performs a cleaning process on the substrate. The conveying device 700 conveys the substrate on which the cleaning process has been performed to the rotary rinsing and drying module 600. The rotary rinsing and drying module 600 performs a drying process on the substrate. The conveying device 700 transfers the substrate on which the drying process has been performed to the transfer robot 110. The transfer robot 110 conveys the substrate received from the conveying device 700 to the cassette at the loading port 100. Finally, the cassette containing the substrate is taken out from the loading port 100.

[0058] In addition, Figure 1 , Figure 2 the structure of the plating apparatus 1000 described Figure 1 , Figure 2 is merely an example, and the structure of the plating apparatus 1000 is not limited to

[0059] Next, the plating module 400 will be described. In addition, since the multiple plating modules 400 included in the plating apparatus 1000 according to the present embodiment have the same structure, one plating module 400 will be described.

[0060] Figure 3 It is a schematic diagram showing the structure of the plating module 400 of the plating apparatus 1000 according to the present embodiment. Specifically, Figure 3 It schematically shows the plating module 400 in a state before the removal of bubbles described later. The plating apparatus 1000 according to the present embodiment is a cup-type plating apparatus. The plating module 400 of the plating apparatus 1000 includes a plating bath 10, an overflow bath 20, a substrate holder 30, a rotation mechanism 40, and a lifting mechanism 50.

[0061] The plating bath 10 according to the present embodiment is composed of a bottomed container having an opening at the upper part. Specifically, the plating bath 10 has a bottom wall 10a and an outer peripheral wall 10b extending upward from the outer peripheral edge of the bottom wall 10a, and the upper part of the outer peripheral wall 10b is open. In addition, the shape of the outer peripheral wall 10b of the plating bath 10 is not particularly limited, and as an example, the outer peripheral wall 10b according to the present embodiment has a cylindrical shape. A plating solution Ps is stored inside the plating bath 10. In addition, a supply port (not shown) for supplying the plating solution Ps to the plating bath 10 is provided in the plating bath 10.

[0062] As the plating solution Ps, any solution containing ions of metal elements constituting the coating film may be used, and specific examples thereof are not particularly limited. In the present embodiment, as an example of the plating process, copper plating is used, and as an example of the plating solution Ps, a copper sulfate solution is used. In addition, in the present embodiment, the plating solution Ps contains a prescribed additive. However, it is not limited to this structure, and the plating solution Ps can also be configured to contain no additive.

[0063] An anode 11 is disposed inside the plating bath 10. Specifically, as an example, the anode 11 according to the present embodiment is disposed on the bottom wall 10a of the plating bath 10. The specific type of the anode 11 is not particularly limited, and it may be a non-dissolving anode or a dissolving anode. In the present embodiment, as an example of the anode 11, a non-dissolving anode is used. The specific type of this non-dissolving anode is not particularly limited, and platinum, iridium oxide, etc. can be used.

[0064] Inside the plating bath 10, a porous resistor 12 is disposed above the anode 11. Specifically, the resistor 12 is composed of a porous plate member having a plurality of holes 12a (fine holes) (in addition, the reference numeral of the hole 12a is shown in the following Figure 4)。The hole 12a of the resistor body 12 according to this embodiment is a through hole provided to connect the lower surface and the upper surface of the resistor body 12. The resistor body 12 is a component provided to equalize the electric field formed between the anode 11 and the substrate Wf as the cathode (the reference numeral is shown in Figure 5 ). Thus, by disposing the resistor body 12 in the plating tank 10, it is possible to easily equalize the film thickness of the coating film (plating layer) formed on the substrate Wf.

[0065] The overflow tank 20 is disposed outside the plating tank 10 and is composed of a container with a bottom. The overflow tank 20 is a tank provided to temporarily accumulate the plating solution Ps that exceeds the upper end of the outer peripheral wall 10b of the plating tank 10 (that is, the plating solution Ps that overflows from the plating tank 10). After the plating solution Ps temporarily accumulated in the overflow tank 20 is discharged from the discharge port (not shown) for the overflow tank 20, it is temporarily accumulated in a storage tank (not shown) for the overflow tank 20. The plating solution Ps accumulated in this storage tank is then pumped by a pump (not shown) and circulated again to the plating tank 10 from the supply port for the plating solution.

[0066] Figure 4 is a schematic cross-sectional view showing a state in which a dummy substrate Wfx described later is immersed in the plating solution Ps when removing bubbles. Figure 5 is a cross-sectional view schematically showing a state in which the substrate holder 30 holds the substrate Wf as the cathode. Refer to Figure 3 、 Figure 4 and Figure 5 , the substrate holder 30 is disposed at a position above the resistor body 12.

[0067] As Figure 5 shows, during the "plating process" of performing the plating process on the substrate Wf, the substrate holder 30 holds the substrate Wf (that is, the substrate Wf on which the plating process is performed) such that the lower surface (the surface to be plated) of the substrate Wf faces the resistor body 12.

[0068] On the other hand, as Figure 3 、 Figure 4 shows, during the "bubble removal" of removing the bubbles remaining in the resistor body 12, the substrate holder 30 holds the dummy substrate Wfx that has not been subjected to the plating process instead of the substrate Wf such that the lower surface Wfa of the dummy substrate Wfx faces the resistor body 12. That is, the substrate holder 30 according to this embodiment is configured to selectively hold the substrate Wf on which the plating process is performed and the dummy substrate Wfx that has not been subjected to the plating process.

[0069] Refer to Figure 3In particular, in the enlarged view of part A1, the substrate holder 30 according to the present embodiment has a ring 31 provided to protrude downward from the outer peripheral edge of the lower surface Wfa of the dummy substrate Wfx (and the lower surface of the substrate Wf). The ring 31 has an annular shape when viewed from above.

[0070] In addition, a sealing member for suppressing the intrusion of the plating solution Ps into the gap between the substrate holder 30 and the dummy substrate Wfx is disposed between the substrate holder 30 and the dummy substrate Wfx. That is, in this case, the substrate holder 30 holds the dummy substrate Wfx via the sealing member. As the material of the sealing member, for example, fluororubber (FKM) or the like can be used.

[0071] Refer to Figure 3 , the substrate holder 30 is connected to a rotation mechanism 40. The rotation mechanism 40 is a mechanism for rotating the substrate holder 30. Figure 3 The “R1” illustrated is an example of the rotation direction of the substrate holder 30. As the rotation mechanism 40, a known rotation motor or the like can be used. The lifting mechanism 50 is supported by a support shaft 51 extending in the vertical direction. The lifting mechanism 50 is a mechanism for lifting the substrate holder 30 and the rotation mechanism 40 in the vertical direction. As the lifting mechanism 50, a known lifting mechanism such as a direct-acting actuator can be used.

[0072] The operation of the plating module 400 is controlled by a control module 800. The control module 800 includes a microcomputer, and the microcomputer includes a CPU (Central Processing Unit) 801 as a processor, a storage device 802 as a non-temporary storage medium, and the like. The control module 800 causes the CPU 801 as a processor to operate based on the instructions of the program stored in the storage device 802, thereby controlling the operation of the controlled parts (for example, the rotation mechanism 40, the lifting mechanism 50, etc.) of the plating module 400.

[0073] However, in the plating apparatus 1000, due to certain reasons, bubbles (Bu) sometimes occur in the plating solution Ps in the plating tank 10. Specifically, as in the present embodiment, when an insoluble anode is used as the anode 11, during the plating process of the substrate Wf (i.e., when energized), oxygen (O2) is generated in the plating solution Ps based on the following reaction formula. In this case, the generated oxygen may become bubbles.

[0074] 2H2O→O2+4H + +4e -

[0075] In addition, in the case where a soluble anode is assumed to be used as the anode 11, the above-described reaction formula is not generated. However, for example, when the plating solution Ps is first introduced into the plating tank 10, air may flow into the plating tank 10 together with the plating solution Ps. Therefore, even when a soluble anode is used as the anode 11, there is a possibility that bubbles are generated in the plating solution Ps in the plating tank 10.

[0076] As described above, when bubbles are generated in the plating solution Ps in the plating tank 10, these bubbles sometimes remain on the lower surface of the resistor 12 and in the holes 12a of the resistor 12. In such a state, when the plating process is performed on the substrate Wf, there is a concern that the plating quality of the substrate Wf deteriorates due to the remaining bubbles. Therefore, in the present embodiment, in order to address this problem, the technique described below is used.

[0077] First, the dummy substrate Wfx will be described. Figure 6 It is a schematic bottom view showing the state of the dummy substrate Wfx observed from below. Refer to Figure 3 and Figure 6 , the dummy substrate Wfx is a substrate that is held by the substrate holder 30 instead of the substrate Wf when removing bubbles. In the present embodiment, the outer peripheral edge of the lower surface Wfa of the dummy substrate Wfx has a circular shape.

[0078] At least one convex portion 60 protruding downward is provided on the lower surface Wfa of the dummy substrate Wfx. That is, the number of the convex portions 60 may be one or plural. In the present embodiment, as an example, the number of the convex portions 60 is one.

[0079] The convex portion 60 is configured such that when the substrate holder 30 rotates in a state where the convex portion 60 of the dummy substrate Wfx is immersed in the plating solution Ps, the pressure difference generated around the convex portion 60 sucks up the bubbles on the lower surface of the resistor 12 and inside the holes 12a (that is, the bubbles remaining on the resistor 12). Specifically, when the substrate holder 30 rotates in a state where the convex portion 60 is immersed in the plating solution Ps, the back side (the surface opposite to the rotation direction) in the rotation direction of the convex portion 60 becomes a negative pressure. By using this negative pressure, the bubbles remaining on the resistor 12 can be sucked upward.

[0080] Specifically, the convex portion 60 according to the present embodiment is configured to extend in a specified direction along the lower surface Wfa of the dummy substrate Wfx. More specifically, the convex portion 60 according to the present embodiment extends in the radial direction of the lower surface Wfa of the dummy substrate Wfx.

[0081] More specifically, the convex portion 60 according to the present embodiment extends radially from the center Ce of the lower surface Wfa of the dummy substrate Wfx toward one side and the other side (in other words, the convex portion 60 extends in the diameter direction of the lower surface Wfa of the dummy substrate Wfx).

[0082] In addition, referring to Figure 3 the enlarged view of the A1 portion of, the convex portion 60 according to the present embodiment is provided with a space 70 between the inner peripheral surface of the ring 31 of the substrate holder 30 so that the convex portion 60 does not contact the ring 31.

[0083] The length of this space 70, that is, the specific value of the distance (d1) between the convex portion 60 and the ring 31 is not particularly limited. If numerical examples are listed, a value selected from a range greater than 0 mm and 1 mm or less can be used. That is, in the present embodiment, the distance (d1) satisfies 0 mm < d1 ≤ 1 mm.

[0084] According to this structure, compared with the case where the distance (d1) between the convex portion 60 and the ring 31 is greater than 1 mm, since the convex portion 60 extends to the vicinity of the outer peripheral edge of the lower surface Wfa of the dummy substrate Wfx, the bubbles remaining in the vicinity of the outer peripheral edge of the resistor body 12 can be effectively sucked upward.

[0085] In addition, referring to Figure 3 the enlarged view of the A1 portion of, in the state where the dummy substrate Wfx is held by the substrate holder 30, the lower surface 60a of the convex portion 60 according to the present embodiment is located below the lower surface 31a of the ring 31. In other words, the convex portion 60 according to the present embodiment protrudes downward more than the ring 31.

[0086] The protruding height (h1) of the convex portion 60 protruding from the lower surface Wfa of the dummy substrate Wfx is not particularly limited. In the present embodiment, a value selected from a range of 1 mm or more and 100 mm or less is used.

[0087] According to this structure, it is possible to suppress the difficulty of transporting the dummy substrate Wfx due to the excessive protruding height (h1) of the convex portion 60, and it is possible to suppress the reduction of the bubble removal effect of the dummy substrate Wfx described later due to the too low protruding height (h1) of the convex portion 60. That is, according to this structure, the ease of transporting the dummy substrate Wfx can be ensured, and the bubbles remaining in the resistor body 12 can be sufficiently removed.

[0088] In addition, if a preferred numerical example of the protruding height (h1) of the convex portion 60 is listed, a value selected from a range of 3 mm or more and 50 mm or less is preferred. Specifically, a value selected from a range of 5 mm or more and 20 mm or less is more preferred, and 10 mm is further preferred. In the present embodiment, as a specific example of this protruding height (h1), 10 mm is used.

[0089] Alternatively, a stirrer for stirring the plating solution Ps may be disposed between the convex portion 60 and the resistor body 12, and the plating solution Ps may be stirred by the stirrer.

[0090] The materials of the dummy substrate Wfx and the convex portion 60 are not particularly limited, and for example, resins, metals, glasses, silicon, or combinations thereof can be used.

[0091] In addition, when using a metal as the material of the dummy substrate Wfx and the convex portion 60, a resin may be coated on the surfaces of the dummy substrate Wfx and the convex portion 60 made of metal. According to this structure, it is possible to effectively prevent the metal components of the dummy substrate Wfx and the convex portion 60 from dissolving in the plating solution Ps and contaminating the plating solution Ps.

[0092] The manufacturing method of the dummy substrate Wfx is not particularly limited, and for example, the following manufacturing method can be used. Specifically, a substrate having a flat lower surface on which the convex portion 60 is not formed is prepared, and the lower surface of the prepared substrate is cut to form the convex portion 60 on the lower surface. Thereby, the dummy substrate Wfx can be manufactured. That is, in this case, the dummy substrate Wfx is integrally formed with the convex portion 60 and the portion other than the convex portion 60 of the dummy substrate Wfx (i.e., the "dummy substrate main body") by cutting.

[0093] Alternatively, by preparing the convex portion 60 in advance and joining the prepared convex portion 60 to the lower surface of a substrate (i.e., the dummy substrate main body) having a flat lower surface, it is also possible to manufacture the dummy substrate Wfx having the convex portion 60 on the lower surface Wfa.

[0094] Figure 7 It is a flowchart showing an example of the bubble removal method based on the plating apparatus 1000 according to the present embodiment. This flowchart is executed during the bubble removal for removing the bubbles remaining in the resistor body 12. In addition, the specific execution timing of the bubble removal (i.e., the specific timing of executing Figure 7 this flowchart) is not particularly limited. For example, the bubble removal may be performed when the plating solution Ps is first introduced into the plating tank 10. Alternatively, the bubble removal may also be performed after the plating treatment is performed on the substrate Wf. If specific examples are listed, the bubble removal may also be performed after the substrate Wf has been subjected to a specified number of plating treatments. Alternatively, during the maintenance of the plating apparatus 1000, for example, the user may hold the dummy substrate Wfx on the substrate holder 30 to perform the bubble removal.

[0095] First, in step S10, the dummy substrate Wfx is held by the substrate holder 30 so that the lower surface Wfa of the dummy substrate Wfx faces the resistor body 12. In this case, the dummy substrate Wfx can also be transported to the substrate holder 30 by the same method as the transportation method of the substrate Wf. Specifically, the dummy substrate Wfx placed at a "specified placement location" can also be transported to the substrate holder 30 by a "transport mechanism (which includes the above-mentioned transport robot arm 110 and transport device 700)".

[0096] In addition, in this case, as the "specified placement location", a part of the four loading ports 100 exemplified by Figure 1 , Figure 2 can be used. Alternatively, in addition to the four loading ports 100, a dedicated loading port for the dummy substrate Wfx can also be provided and used as the "specified placement location".

[0097] After step S10, the convex portion 60 of the dummy substrate Wfx is immersed in the plating solution Ps in the plating tank 10 (step S11). In the present embodiment, the substrate holder 30 is lowered by the lifting mechanism 50, so that, as Figure 4 exemplified, the convex portion 60 is immersed in the plating solution Ps in the plating tank 10. In addition, at this time, the lifting mechanism 50 immerses the convex portion 60 in the plating solution Ps in a state where the convex portion 60 is located at a specified distance above the resistor body 12, so that the convex portion 60 of the dummy substrate Wfx does not contact the resistor body 12.

[0098] In addition, as Figure 4 exemplified by the enlarged view of the A3 portion of, when the convex portion 60 of the dummy substrate Wfx is immersed in the plating solution Ps in the present embodiment, not only the convex portion 60 but also the portion of the lower surface Wfa of the dummy substrate Wfx where the convex portion 60 is not provided is immersed in the plating solution Ps. That is, when the bubbles are removed from the dummy substrate Wfx according to the present embodiment, the portion of the lower surface Wfa of the dummy substrate Wfx other than the convex portion 60 is also located below the liquid level of the plating solution Ps.

[0099] According to this structure, compared with the case where the portion of the lower surface Wfa of the dummy substrate Wfx where the convex portion 60 is not provided is not immersed in the plating solution Ps (refer to Figure 8 related to the following modification example 1), it is possible to suppress the liquid level fluctuation of the plating solution Ps in the plating tank 10 due to the convex portion 60 when the substrate holder 30 rotates and the convex portion 60 rotates. Thereby, it is possible to suppress the generation of liquid splashing of the plating solution Ps in the plating tank 10.

[0100] In addition, in the present embodiment, the lifting mechanism 50 can also position the substrate holder 30 at a position higher than that during the plating process when the convex portion 60 is immersed in the plating solution Ps during bubble removal. That is, when the ground clearance of the substrate holder 30 during the plating process is the "first specified value", the ground clearance of the substrate holder 30 during bubble removal can also be the "second specified value" higher than the first specified value. According to this structure, it is possible to easily prevent the convex portion 60 of the dummy substrate Wfx from contacting the resistor body 12 during bubble removal.

[0101] However, it is not limited to the above structure. For example, the lifting mechanism 50 can also not position the substrate holder 30 at a position higher than that during the plating process when the convex portion 60 is immersed in the plating solution Ps during bubble removal.

[0102] After Figure 7 step S11, step S12 is executed. In step S12, the rotation mechanism 40 rotates the substrate holder 30 in a state where the convex portion 60 of the dummy substrate Wfx is located above the resistor body 12 and the convex portion 60 of the dummy substrate Wfx is immersed in the plating solution Ps.

[0103] In this way, when the substrate holder 30 rotates in step S12, the dummy substrate Wfx held by the substrate holder 30 also rotates, and the convex portion 60 also rotates. As a result, the pressure difference generated around the convex portion 60 on the lower surface Wfa of the dummy substrate Wfx can suck up the bubbles on the lower surface of the resistor body 12 and inside the holes 12a (i.e., the bubbles staying on the resistor body 12). Thus, the bubbles staying on the resistor body 12 can be removed.

[0104] In addition, after step S12 is executed (i.e., after bubble removal), the rotation mechanism 40 stops the rotation of the substrate holder 30, and the lifting mechanism 50 raises the substrate holder 30 so that the dummy substrate Wfx is located above the plating solution Ps. Then, the dummy substrate Wfx is removed from the substrate holder 30 (step S13).

[0105] According to the present embodiment described above, by executing step S12, the bubbles staying on the resistor body 12 in the plating tank 10 can be removed. Thus, it is possible to suppress the deterioration of the plating quality of the substrate Wf due to the staying bubbles when plating the substrate Wf.

[0106] (Modification Example 1 of the Embodiment)

[0107] In addition, during bubble removal in the above embodiment, the portion of the lower surface Wfa of the dummy substrate Wfx where the convex portion 60 is not provided is also immersed in the plating solution Ps, but it is not limited to this structure. Figure 8It is a schematic cross-sectional view showing a part (part A3) of the peripheral structure of the convex portion 60 when removing bubbles of the plating apparatus 1000A according to Modification Example 1 of the embodiment in an enlarged manner. As Figure 8 shown, when removing bubbles, it is also possible to not immerse the portion of the lower surface Wfa of the dummy substrate Wfx where the convex portion 60 is not provided in the plating solution Ps, and only immerse the convex portion 60 in the plating solution Ps.

[0108] In this modification example, similar to the plating apparatus 1000 according to the above-described embodiment, it is possible to remove the bubbles remaining in the resistor body 12. Thereby, it is possible to suppress the deterioration of the plating quality of the substrate Wf due to the remaining bubbles when performing the plating process on the substrate Wf.

[0109] In addition, in the above-described embodiment and Modification Example 1, the shape of the convex portion 60 is not limited to Figure 5 the shape exemplified. Hereinafter, modification examples (Modification Examples 2 to 6) of the convex portion 60 will be described.

[0110] (Modification Example 2 of the Embodiment)

[0111] Figure 9 It is a schematic bottom view of the dummy substrate Wfx of the plating apparatus 1000B according to Modification Example 2 of the embodiment. The convex portion 60B according to this modification example extends only in one radial direction from the center Ce of the lower surface Wfa (that is, does not extend in the other radial direction). In other words, the convex portion 60B extends only in the radial direction of the lower surface Wfa of the dummy substrate Wfx. In this modification example, the same operational effects as those of the plating apparatus 1000 according to the above-described embodiment can also be achieved.

[0112] (Modification Example 3 of the Embodiment)

[0113] Figure 10 It is a schematic bottom view of the dummy substrate Wfx of the plating apparatus 1000C according to Modification Example 3 of the embodiment. The dummy substrate Wfx according to this modification example includes a plurality of convex portions. The number of the plurality of convex portions is not particularly limited, and may be two, three, or four or more. In this modification example, as an example, the number of the plurality of convex portions is two. Specifically, the plurality of convex portions according to this modification example are the convex portion 60C-1 and the convex portion 60C-2.

[0114] The convex portion 60C-1 has the same as the above Figure 6has the same structure as the convex portion 60. On the other hand, the convex portion 60C-2 intersects the convex portion 60C-1 and extends radially from the center Ce toward one side and the other side. That is, the convex portion 60C-2 is a replication (or rotational replication) of arranging the convex portion 60C-1 in a circular shape. In addition, the angle formed by the convex portion 60C-1 and the convex portion 60C-2 is not particularly limited. In this modification example, as an example, it is 90 degrees.

[0115] In this modification example, the same effects as those of the plating apparatus 1000 according to the above-described embodiment can also be achieved. In addition, according to this modification example, since there are a plurality of convex portions, compared with the case where there is only one convex portion, bubbles can be effectively sucked up. Thus, bubbles remaining in the resistor body 12 can be effectively suppressed.

[0116] In addition, the above Figure 9 The dummy substrate Wfx according to the modification example 2 illustrated may also have a plurality of convex portions 60B. That is, the dummy substrate Wfx may also have a plurality of Figure 9 convex portions 60B that extend only toward one side in the radial direction from the center Ce of the lower surface Wfa as illustrated.

[0117] (Modification Example 4 of the Embodiment)

[0118] Figure 11 is a schematic bottom view of the dummy substrate Wfx of the plating apparatus 1000D according to the modification example 4 of the embodiment. The convex portion 60D of the dummy substrate Wfx according to this modification example is different from the Figure 6 convex portion 60 in that at least a part of it has a bent portion that bends in the circumferential direction of the dummy substrate Wfx. Specifically, the convex portion 60D according to this modification example has a bent portion 61a and a bent portion 61b.

[0119] The bent portion 61a is disposed on one side in the radial direction of the lower surface Wfa with respect to the center Ce, and the bent portion 61b is disposed on the other side in the radial direction of the lower surface Wfa with respect to the center Ce. The bent portion 61a and the bent portion 61b are bent to protrude toward the circumferential direction of the lower surface Wfa of the dummy substrate Wfx.

[0120] In this modification example, the same effects as those of the plating apparatus 1000 according to the above-described embodiment can also be achieved.

[0121] In addition, the dummy substrate Wfx according to this modification example may also have a plurality of convex portions 60D.

[0122] (Modification Example 5 of the Embodiment)

[0123] Figure 12It is a schematic bottom view of the dummy substrate Wfx of the plating apparatus 1000E according to Modification Example 5 of the embodiment. The convex portion 60E of the dummy substrate Wfx according to this modification example includes a first portion 62 and a second portion (second portion 63a and second portion 63b). The first portion 62 is a portion that extends radially on the lower surface Wfa from the center Ce of the lower surface Wfa of the dummy substrate Wfx toward the outer peripheral edge of the dummy substrate Wfx. Specifically, the first portion 62 according to this embodiment extends from the center Ce toward the outer peripheral edge of the dummy substrate Wfx and extends radially on the lower surface Wfa toward one side and the other side, respectively.

[0124] The second portion 63a and the second portion 63b are portions that are connected to the end portions on the outer peripheral edge side of the first portion 62 and are inclined with respect to the first portion 62. Specifically, the second portion 63a is connected to one end portion 62a among the end portions 62a and 62b on the outer peripheral edge side of the first portion 62, and the second portion 63b is connected to the other end portion 62b.

[0125] In addition, the inclination angle (θ) at which the second portion 63a and the second portion 63b are inclined with respect to the first portion 62 is not particularly limited. In this modification example, it is a value selected from a range greater than 0 degrees and less than 90 degrees. Specifically, it is a value selected from a range of 10 degrees or more and 45 degrees or less. In addition, in this modification example, the inclination angles of the second portion 63a and the second portion 63b are the same value. However, the structure is not limited to this, and the inclination angles of the second portion 63a and the second portion 63b may also be different values from each other.

[0126] In addition, in this modification example, the convex portion 60E includes two second portions (second portion 63a and second portion 63b), but the structure is not limited to this. The convex portion 60E may also include only either the second portion 63a or the second portion 63b.

[0127] In this modification example, the same effects as those of the plating apparatus 1000 according to the above embodiment can also be achieved.

[0128] In addition, the dummy substrate Wfx according to this modification example may also have a plurality of convex portions 60E. If one example is cited, the dummy substrate Wfx according to the above Modification Example 3 ( Figure 10 ) may also include the second portion according to this modification example.

[0129] In addition, the dummy substrate Wfx according to the above Modification Example 2 ( Figure 9 ) may also include the second portion according to this modification example. In this case, the dummy substrate Wfx may also have a plurality of convex portions having the second portion.

[0130] (Modification Example 6 of the Embodiment)

[0131] Figure 13 It is a schematic bottom view of the dummy substrate Wfx of the plating apparatus 1000F according to Modification Example 6 of the embodiment. The dummy substrate Wfx according to this modification example has a plurality of convex portions. Specifically, the plurality of convex portions according to this modification example are convex portion 60F-1, convex portion 60F-2, convex portion 60F-3, convex portion 60F-4, and convex portion 60F-5.

[0132] In addition, the plurality of convex portions according to this modification example have the following structure: when the lower surface Wfa of the dummy substrate Wfx is divided by a plurality of imaginary concentric circles (imaginary concentric circles C1, C2, C3, C4), at least one convex portion is disposed in each region divided by the plurality of imaginary concentric circles.

[0133] Specifically, convex portion 60F-1 is disposed in the region inside imaginary concentric circle C1, and convex portion 60F-2 is disposed in the region between imaginary concentric circles C1 and C2. In addition, convex portion 60F-3 is disposed in the region between imaginary concentric circles C2 and C3, and convex portion 60F-4 is disposed in the region between imaginary concentric circles C3 and C4. Moreover, convex portion 60F-5 is disposed in the region outside imaginary concentric circle C4.

[0134] In addition, the convex portions disposed in each region extend in the radial direction of the lower surface Wfa of the dummy substrate Wfx. Moreover, as an example, the angle formed by the extending direction of the convex portion disposed in one region of a pair of adjacent regions and the extending direction of the convex portion disposed in the other region is 90 degrees.

[0135] Specifically, the angles formed by convex portion 60F-1 and convex portion 60F-2, convex portion 60F-2 and convex portion 60F-3, convex portion 60F-3 and convex portion 60F-4, and convex portion 60F-4 and convex portion 60F-5 are 90 degrees, respectively.

[0136] In this modification example, the same effects as those of the plating apparatus 1000 according to the above embodiment can also be achieved.

[0137] In addition, in this modification example, the angle formed by the extending direction of the convex portion disposed in one region of a pair of adjacent regions and the extending direction of the convex portion disposed in the other region is not limited to 90 degrees. This formed angle can be smaller than 90 degrees or larger than 90 degrees. In addition, in Figure 13 it, one convex portion is disposed in each region divided by the plurality of imaginary concentric circles, but it is not limited to this structure. Two or more convex portions can also be disposed in each region divided by the plurality of imaginary concentric circles.

[0138] (Modification Example 7 of the Embodiment)

[0139] Figure 14 FIG. 5 is a schematic bottom view of the dummy substrate Wfx of the plating apparatus 1000G according to Modification Example 7 of the embodiment. The dummy substrate Wfx according to this modification example is different from the dummy substrate Wfx according to the embodiment exemplified in FIG. 2 in that it further includes an orientation plane ORF and a notch NT. Figure 6 The dummy substrate Wfx according to this modification example is different from the dummy substrate Wfx according to the embodiment exemplified in FIG. 2 in that it further includes an orientation plane ORF and a notch NT.

[0140] In addition, the conveyance of the dummy substrate Wfx according to this modification example can also be performed by the same method as in the case of conveying the substrate Wf. That is, after the aligner 120 aligns the positions of the orientation plane ORF and the notch NT of the dummy substrate Wfx with a specified direction, the conveyance mechanism can convey the dummy substrate Wfx to the substrate holder 30.

[0141] In this modification example, the same effects as those of the plating apparatus 1000 according to the above embodiment can also be achieved.

[0142] Alternatively, the dummy substrate Wfx according to this modification example may include only one of the orientation plane ORF and the notch NT. That is, the dummy substrate Wfx may have a structure including the orientation plane ORF but not the notch NT, or may have a structure including the notch NT but not the orientation plane ORF.

[0143] Alternatively, the dummy substrate Wfx according to Modification Examples 2 to 6 described above may include at least one of the orientation plane ORF and the notch NT.

[0144] (Modification Example 8 of the Embodiment)

[0145] In the above embodiment and Modification Examples 1 to 7, after removing bubbles using the dummy substrate Wfx, ultrasonic waves may be sent along the lower surface of the resistor 12, and based on these ultrasonic waves, it may be confirmed whether there are bubbles on the lower surface of the resistor 12 (hereinafter, this process is referred to as the "bubble confirmation process"). Specifically, this bubble confirmation process may be performed after step S12 described above and before step S13. The structure of the plating apparatus 1000H according to this modification example is as follows. Figure 7 The structure of the plating apparatus 1000H according to this modification example is as follows.

[0146] Figure 15 FIG. 6 is a schematic cross-sectional view showing the peripheral structure of the plating bath 10 of the plating apparatus 1000H according to this modification example. In addition, in Figure 15In the figure, illustrations of the overflow tank 20 and the like are omitted. The plating apparatus 1000H includes a transmitter 80 and a receiver 81 at a position below the specific resistance body 12 on the outer peripheral wall 10b of the plating tank 10. The transmitter 80 transmits ultrasonic waves (UL) along the lower surface of the resistance body 12.

[0147] The receiver 81 is configured to receive the ultrasonic waves transmitted by the transmitter 80. Specifically, the receiver 81 according to this modification example is disposed on the outer peripheral wall 10b so as to face the transmitter 80. The transmitter 80 and the receiver 81 are controlled by a control module 800.

[0148] In the bubble confirmation process (that is, when confirming bubbles), the transmitter 80 transmits ultrasonic waves along the lower surface of the resistance body 12. The receiver 81 transmits information about the received ultrasonic waves to the control module 800. The control module 800 determines whether there are bubbles on the lower surface of the resistance body 12 based on the ultrasonic waves received by the receiver 81.

[0149] Specifically, when the ultrasonic waves transmitted by the transmitter 80 hit bubbles (bubbles existing on the lower surface of the resistance body 12), the intensity of the ultrasonic waves received by the receiver 81 has a tendency to weaken compared to the case where the ultrasonic waves transmitted by the transmitter 80 do not hit bubbles and are received by the receiver 81. Therefore, it is possible to determine whether there are bubbles on the lower surface of the resistance body 12 based on the intensity of the ultrasonic waves received by the receiver 81.

[0150] Therefore, the control module 800 according to this modification example determines whether there are bubbles on the lower surface of the resistance body 12 based on whether the intensity of the ultrasonic waves received by the receiver 81 is lower than a preset specified value.

[0151] As described above, the embodiments and modification examples of the present invention have been described in detail, but the present invention is not limited to the above specific embodiments and modification examples, and various further modifications and changes can be made within the scope of the gist of the present invention described in the claims.

[0152] Description of Reference Numerals

[0153] 10... plating tank; 11... anode; 12... resistance body; 30... substrate holder; 31... ring; 40... rotating mechanism; 50... lifting mechanism; 60... convex portion; 70... space; 1000... plating apparatus; Wf... substrate; Wfx... dummy substrate; Ps... plating solution; Bu... bubble; UL... ultrasonic wave.

Claims

1. A plating apparatus, wherein, Comprising: A plating bath that stores a plating solution and is internally provided with a porous resistor; A substrate holder disposed at a position above the resistor and holding a dummy substrate; A rotating mechanism that rotates the substrate holder; And A lifting mechanism that raises and lowers the substrate holder, At least one convex portion protruding downward from the lower surface of the dummy substrate is provided on the lower surface of the dummy substrate, The substrate holder has a ring protruding downward from the outer peripheral edge of the lower surface of the dummy substrate, The lower surface of the convex portion is located at a position lower than the lower surface of the ring, The plating apparatus is configured such that in a state where the lifting mechanism lowers the substrate holder and the convex portion of the dummy substrate is located above the resistor and the convex portion is immersed in the plating solution in the plating bath, the rotating mechanism rotates the substrate holder.

2. The plating apparatus according to claim 1, wherein, A space is provided between the convex portion and the ring so that the convex portion does not contact the ring.

3. The plating apparatus according to claim 1, wherein, The protruding height of the convex portion protruding from the lower surface of the dummy substrate is a value selected from the range of 1 mm or more and 100 mm or less.

4. The plating apparatus according to claim 1, wherein, The convex portion extends in the radial direction of the lower surface of the dummy substrate.

5. The plating apparatus according to claim 4, wherein, At least a part of the convex portion has a bent portion bent in the circumferential direction of the dummy substrate.

6. The plating apparatus according to claim 1, wherein, The convex portion has: A first portion extending in the radial direction of the lower surface of the dummy substrate from the center of the lower surface of the dummy substrate toward the outer peripheral edge of the lower surface of the dummy substrate; And A second portion connected to the end portion on the outer peripheral edge side of the first portion and inclined with respect to the first portion.

7. The plating apparatus according to claim 1, wherein, When the lower surface of the dummy substrate is divided by a plurality of imaginary concentric circles, at least one convex portion is disposed in each region divided by the plurality of imaginary concentric circles.

8. The plating apparatus according to claim 1, wherein, The substrate holder is configured to hold the substrate during a plating process for plating the substrate and hold the dummy substrate when removing bubbles remaining at the resistor, When removing the bubbles remaining at the resistor, the lifting mechanism positions the substrate holder at a position higher than that during the plating process.

9. The plating apparatus according to claim 1, wherein, When immersing the convex portion of the dummy substrate in the plating solution in the plating bath, the lifting mechanism also immerses the portion of the lower surface of the dummy substrate where the convex portion is not provided in the plating solution in the plating bath.

10. The plating apparatus according to claim 1, wherein, A conveying mechanism is further provided, and the conveying mechanism conveys the dummy substrate placed on a specified placement location to the substrate holder, The substrate holder is configured to hold the substrate during a plating process for plating the substrate and hold the dummy substrate conveyed by the conveying mechanism with the substrate holder when removing bubbles remaining at the resistor.

11. The plating apparatus according to claim 1, wherein, The rotating mechanism rotates the substrate holder to rotate the dummy substrate held by the substrate holder.

12. The plating apparatus according to claim 2, wherein, The horizontal distance between the convex portion and the ring is a value selected from the range greater than 0 mm and 1 mm or less.

13. A method for removing bubbles, which is a method for removing bubbles remaining in a resistor body in a plating bath, the plating bath storing a plating solution and having the porous resistor body disposed therein, wherein, The method for removing bubbles includes: Holding a dummy substrate having a lower surface provided with at least one convex portion protruding downward on a substrate holder; Lower the substrate holder that holds the dummy substrate, and immerse the convex portion in the plating solution in the plating tank with the convex portion positioned above the resistor body; and While the convex portion of the dummy substrate is positioned above the resistor body and the convex portion is immersed in the plating solution in the plating tank, rotate the substrate holder, The substrate holder has a ring that protrudes downward from the outer peripheral edge of the lower surface of the dummy substrate, The lower surface of the convex portion is positioned below the lower surface of the ring.

Images