Plating method and plating apparatus

Abstract

Provided is a technique capable of achieving uniform film thickness. The plating method includes a supply process (S5) of supplying a substrate to a plating bath in which an anode and an intermediate member are disposed. The substrate is supplied to a location where it does not contact the intermediate member. The substrate has a pattern formation region in which a plurality of patterns are formed, the contour shape of the pattern formation region is non-circular, and the intermediate member has, in a plan view, a hole formation region in which a plurality of holes through which the plating solution can pass are formed, and an electric field shielding region disposed around the hole formation region. The contour shape of the hole formation region corresponds to the contour shape of the pattern formation region. The supply process, an alignment process (S10) of adjusting the position of the substrate so that the contour shape of the pattern formation region and the contour shape of the hole formation region are spatially aligned, and a first energization process (S20) of energizing the anode and the substrate while causing the substrate to perform a rocking rotational motion.

Description

Technical Field

[0001] The present invention relates to a plating method and a plating apparatus.

Background Art

[0002] Conventionally, a plating apparatus capable of performing a plating process on a substrate has been known (see, for example, Patent Document 1). Specifically, in the plating apparatus exemplified in Patent Document 1, an anode is disposed inside a plating tank in which a plating solution is stored, a substrate as a cathode is disposed above the anode, an ion resistor is disposed between the anode and the substrate, and an electric field shielding member is disposed between the ion resistor and the substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, as a substrate to be plated, a substrate having a non-circular contour shape in the pattern formation region of the substrate may be used. A plating method capable of making the thickness (film thickness) of the plating film formed on such a substrate uniform has not been sufficiently developed so far.

[0005] The present invention has been made in view of the above, and one of its objects is to provide a technique capable of achieving uniform film thickness.

Means for Solving the Problems

[0006] (Aspect 1) To achieve the above object, a plating method according to an aspect of the present invention is a supply process of supplying a substrate to a plating bath in which an anode and an intermediate member are disposed. The intermediate member is disposed between the anode and the substrate supplied to the plating bath. The substrate is supplied to a location where it does not contact the intermediate member. The substrate has a pattern formation region in which a plurality of patterns are formed. The contour shape of the pattern formation region is non-circular. The intermediate member has, in a plan view, a hole formation region in which a plurality of holes through which a plating solution can pass are formed, and an electric field shielding region disposed around the hole formation region. The contour shape of the hole formation region corresponds to the contour shape of the pattern formation region. The supply process, an alignment process of adjusting the position of the substrate so that the contour shape of the pattern formation region and the contour shape of the hole formation region are spatially aligned, and a first energization process of energizing the anode and the substrate while causing the substrate to perform a rocking rotational motion. In the rocking rotational motion, the substrate rotates by a first angle in a first rotation direction and rotates by a second angle in a second rotation direction opposite to the first rotation direction, at least once, centering on a state where the contour shape of the pattern formation region is aligned with the contour shape of the hole formation region.

[0007] (Aspect 2) In the above Aspect 1, the first angle may be 45° or less, and the second angle may be 45° or less.

[0008] (Aspect 3) In the above Aspect 1 or 2, the contour shape of the pattern formation region may be configured to appear the same before and after rotation when the substrate is rotated by a rotation symmetry angle of less than 360°.

[0009] (Aspect 4) In the above-described Embodiment 3, the plating method may further include a rotation process of rotating the substrate by the rotationally symmetric angle in a state where energization to the anode and the substrate is stopped after the first energization process, and a second energization process of energizing the anode and the substrate while causing the substrate to perform the rocking rotational motion after the rotation process.

[0010] (Embodiment 5) In the above-described Embodiment 4, after the execution of the second energization process, a series of processes including the rotation process and the second energization process may be further executed at least once.

[0011] (Embodiment 6) In the above-described Embodiment 5, the series of processes may be executed a plurality of times.

[0012] (Embodiment 7) In the above-described Embodiment 6, in the rotation process executed a plurality of times, the rotation direction of the substrate in the rotation process executed at an arbitrary time and the rotation direction of the substrate in the next rotation process may be in opposite directions.

[0013] (Embodiment 8) In the above-described Embodiment 6, in the rotation process executed a plurality of times, the rotation direction of the substrate in the rotation process executed at an arbitrary time and the rotation direction of the substrate in the next rotation process may be in the same direction.

[0014] (Embodiment 9) In any one of the above-described Embodiments 4 to 8, the rotation speed of the substrate in the rocking rotational motion and the rotation speed of the substrate in the rotation process may be the same value.

[0015] (Embodiment 10) In any one of the above-described Embodiments 4 to 8, the rotation speed of the substrate in the rocking rotational motion and the rotation speed of the substrate in the rotation process may be different values.

[0016] (Embodiment 11) In the above-described aspect 10, the rotation speed of the substrate in the rocking rotational movement may be slower than the rotation speed of the substrate in the rotation process.

[0017] (Aspect 12) In any one of the above-described aspects 1 to 11, the intermediate member may include an ion resistor having the hole formation region and the electric field shielding region.

[0018] (Aspect 13) In any one of the above-described aspects 1 to 11, the intermediate member includes an ion resistor in which the plurality of holes are formed, and an electric field shielding member having an opening disposed above the ion resistor. The electric field shielding region is constituted by a region around the opening of the electric field shielding member, and the hole formation region is constituted by a region in which the plurality of holes of the ion resistor located inside the opening of the electric field shielding member are formed in a plan view. The contour shape of the hole formation region may be constituted by the contour of the opening of the electric field shielding member.

[0019] (Aspect 14) In order to achieve the above object, an electroplating apparatus according to an aspect of the present invention includes a control module configured to execute the supply process, the alignment process, and the first energization process described in any one of the above aspects 1 to 13.

Effect of the Invention

[0020] According to the above aspect, the film thickness can be made uniform.

Brief Description of the Drawings

[0021]

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Mode for Carrying Out the Invention

[0022] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the drawings are schematically illustrated to facilitate understanding of the features of the components, and the dimensional ratios and the like of each component are not necessarily the same as the actual ones. In addition, in some of the drawings, X-Y-Z orthogonal coordinates are illustrated for reference. Among these orthogonal coordinates, the Z direction corresponds to upward, and the -Z direction corresponds to downward (the direction in which gravity acts).

[0023] FIG. 1 is a perspective view showing the overall configuration of the plating apparatus 1000 of the present embodiment. FIG. 2 is a plan view (specifically, a top view) showing the overall configuration of the plating apparatus 1000 of the present 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.

[0024] The load port 100 is a module for loading a substrate housed in a cassette such as a FOUP (not shown in the plating apparatus 1000) into the plating apparatus 1000 and unloading the substrate from the plating apparatus 1000 to the cassette. In the present embodiment, four load ports 100 are arranged side by side in the horizontal direction, but the number and arrangement of the load ports 100 are arbitrary. The transfer robot 110 is a robot for transferring the substrate and is configured to transfer the substrate between the load port 100, the aligner 120, the pre-wet module 200, and the spin rinsing dryer 600. When transferring the substrate between the transfer robot 110 and the transfer device 700, the transfer robot 110 and the transfer device 700 can transfer the substrate via a temporary placement table (not shown).

[0025] The aligner 120 is a module for aligning the positions of the orientation flat, notch, etc. of the substrate in a predetermined direction. In the present embodiment, two aligners 120 are arranged side by side in the horizontal direction, but the number and arrangement of the aligners 120 are arbitrary. The pre-wet module 200 wets the surface to be plated of the substrate before the plating process with a processing liquid such as pure water or degassed water, thereby replacing the air inside the pattern formed on the substrate surface with the processing liquid. The pre-wet module 200 is configured to perform a pre-wet process that makes it easier to supply the plating liquid inside the pattern by replacing the processing liquid inside the pattern with the plating liquid during plating. In the present embodiment, two pre-wet modules 200 are arranged one above the other in the vertical direction, but the number and arrangement of the pre-wet modules 200 are arbitrary.

[0026] The presoak module 300 is configured to perform a presoak process of cleaning or activating the surface of the plating base by etching and removing an oxide film with a large electrical resistance present on the surface of a seed layer formed on the surface to be plated of the substrate before plating, for example, with a processing solution such as sulfuric acid or hydrochloric acid. In the present embodiment, two presoak modules 300 are arranged side by side in the vertical direction, but the number and arrangement of the presoak modules 300 are arbitrary. The plating module 400 performs a plating process on the substrate. In the present embodiment, there are two sets of 12 plating modules 400 arranged side by side 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.

[0027] The cleaning module 500 is configured to perform a cleaning process on the substrate in order to remove the plating solution remaining on the substrate after the plating process. In the present embodiment, two cleaning modules 500 are arranged side by side in the vertical direction, but the number and arrangement of the cleaning modules 500 are arbitrary. The spin rinse dryer 600 is a module for drying the substrate by rotating it at high speed after the cleaning process. In the present embodiment, two spin rinse dryers 600 are arranged side by side in the vertical direction, but the number and arrangement of the spin rinse dryers 600 are arbitrary. The transfer device 700 is a device for transferring 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 composed of, for example, a general computer or a dedicated computer having an input / output interface with an operator.

[0028] An example of a series of plating processes by the plating apparatus 1000 will be described. First, the substrate accommodated in the cassette is carried into the load port 100. Subsequently, the transfer robot 110 takes out the substrate from the cassette of the load port 100 and transfers the substrate to the aligner 120. The aligner 120 aligns the positions such as the orientation flat and notch of the substrate in a predetermined direction. The transfer robot 110 delivers the substrate whose direction has been aligned by the aligner 120 to the prewet module 200.

[0029] The pre-wet module 200 performs a pre-wet process on the substrate. The transfer device 700 transfers the substrate 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 subjected to the pre-soak process to the plating module 400. The plating module 400 performs a plating process on the substrate.

[0030] The transfer device 700 transfers the substrate subjected to the plating process to the cleaning module 500. The cleaning module 500 performs a cleaning process on the substrate. The transfer device 700 transfers the substrate subjected to the cleaning process to the spin rinse dryer 600. The spin rinse dryer 600 performs a drying process on the substrate. The transfer robot 110 receives the substrate from the spin rinse dryer 600 and transfers the substrate subjected to the drying process to the cassette at the load port 100. Finally, the cassette containing the substrate is unloaded from the load port 100.

[0031] Note 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 in FIGS. 1 and 2.

[0032] Subsequently, the plating module 400 will be described. Since the plurality of plating modules 400 included in the plating apparatus 1000 according to the present embodiment have the same configuration, one plating module 400 will be described.

[0033] FIG. 3 is a schematic diagram showing the configuration of the plating module 400 in the plating apparatus 1000 according to the present embodiment. Specifically, FIG. 3 schematically illustrates the plating module 400 in a state before the substrate Wf is immersed in the plating solution Ps. FIG. 4 is a schematic diagram showing a state in which the substrate Wf is immersed in the plating solution Ps.

[0034] The plating apparatus 1000 illustrated in FIGS. 3 and 4 is, as an example, a plating apparatus of a type that immerses a substrate Wf in a plating solution Ps with the plane direction of the substrate Wf being horizontal (so-called, a cup-type plating apparatus).

[0035] The plating module 400 of the plating apparatus 1000 illustrated in FIGS. 3 and 4 includes a plating tank 10, an overflow tank 20, and a substrate holder 30. Further, as illustrated in FIG. 3, the plating module 400 according to the present embodiment includes a rotation mechanism 40, an inclination mechanism 45, and a lifting mechanism 50.

[0036] The plating tank 10 according to the present embodiment is configured by a bottomed container having an opening upward. Specifically, the plating tank 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. Note that the shape of the outer peripheral wall 10b of the plating tank 10 is not particularly limited, but the outer peripheral wall 10b according to the present embodiment has a cylindrical shape as an example. A plating solution Ps is stored inside the plating tank 10.

[0037] The plating solution Ps may be a solution containing ions of a metal element constituting a plating film, 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. Further, the plating solution Ps may contain a predetermined additive.

[0038] An anode 11 is disposed inside the plating tank 10. The specific type of the anode 11 is not particularly limited, and it may be an insoluble anode or a soluble anode. In the present embodiment, as an example of the anode 11, an insoluble anode is used. The specific type of this insoluble anode is not particularly limited, and platinum, iridium oxide, or the like can be used.

[0039] Also, during the plating process, inside the plating bath 10, a substrate Wf as a cathode is disposed above the anode 11 (see FIG. 4).

[0040] As illustrated in FIG. 4, the anode 11 and the substrate Wf are electrically connected to an energization device 18. By being controlled by a control module 800 described later, this energization device 18 starts and stops energization (i.e., starts and stops electrical supply) to the anode 11 and the substrate Wf. Note that the specific configuration of the energization device 18 is not particularly limited, but for example, it includes a power source and a switch for starting and stopping electrical supply from the power source.

[0041] Also, during the plating process, an intermediate member 60 is disposed between the anode 11 and the substrate Wf inside the plating bath 10. As illustrated in FIGS. 3 and 4, the intermediate member 60 according to this embodiment is disposed in the plating bath 10 in a manner that does not contact the anode 11 or the substrate Wf (in a non-contact state). Note that during the plating process, it is preferable that the center position of the substrate Wf held by the substrate holder 30 coincides with the center position of the intermediate member 60 disposed in the plating bath 10. Also, during the plating process, it is preferable that the substrate Wf and the intermediate member 60 are parallel. Details of the configuration of the intermediate member 60 will be described later.

[0042] The specific value of the distance between the intermediate member 60 and the substrate Wf during the plating process is not particularly limited, but for example, any value within 50 mm, specifically any value within 40 mm, specifically any value within 30 mm, specifically any value within 15 mm can be used. Note that when a paddle 70 is disposed between the intermediate member 60 and the substrate Wf, it is preferable to set the distance between the intermediate member 60 and the substrate Wf so that the paddle 70 does not contact the intermediate member 60 and the substrate Wf.

[0043] As illustrated in FIGS. 3 and 4, inside the plating tank 10, a film 16 may be disposed at a location above the anode 11 and below the intermediate member 60. In this case, the inside of the plating tank 10 is partitioned by the film 16 into an anode chamber 17a below the film 16 and a cathode chamber 17b above the film 16. The anode 11 is disposed in the anode chamber 17a, and the intermediate member 60 and the substrate Wf are disposed in the cathode chamber 17b. The film 16 is configured to allow ion species containing metal ions included in the plating solution Ps to pass through the film 16 while suppressing the passage of non-ion-based plating additives included in the plating solution Ps through the film 16. As such a film 16, for example, an ion exchange membrane can be used.

[0044] The plating tank 10 is provided with a supply port for supplying the plating solution Ps to the plating tank 10. Specifically, on the outer peripheral wall 10b of the plating tank 10 according to the present embodiment, a first supply port 13a for supplying the plating solution Ps to the anode chamber 17a and a second supply port 13b for supplying the plating solution Ps to the cathode chamber 17b are provided.

[0045] Further, the plating tank 10 is provided with a first discharge port 14a for discharging the plating solution Ps in the anode chamber 17a to the outside of the plating tank 10. The plating solution Ps discharged from the first discharge port 14a is pumped by a pump (not shown) and supplied again from the first supply port 13a to the anode chamber 17a.

[0046] The overflow tank 20 is constituted by a bottomed container disposed outside the plating tank 10. The overflow tank 20 is provided for temporarily storing the plating solution Ps that has exceeded the upper end of the outer peripheral wall 10b of the plating tank 10 (that is, the plating solution Ps that has overflowed from the plating tank 10). The plating solution Ps stored in the overflow tank 20 is discharged from the second discharge port 14b and then pumped by a pump (not shown) and supplied again from the second supply port 13b to the cathode chamber 17b.

[0047] The substrate holder 30 holds the substrate Wf as the cathode such that the plated surface Wfa of the substrate Wf faces the anode 11. In the present embodiment, the plated surface Wfa of the substrate Wf is specifically provided on the surface (lower surface) facing the lower side of the substrate Wf.

[0048] The substrate holder 30 is connected to the rotation mechanism 40. The rotation mechanism 40 is a mechanism for rotating the substrate holder 30. The rotation mechanism 40 according to the present embodiment is indirectly connected to the substrate Wf via the substrate holder 30, and is configured to rotate the substrate Wf by rotating the substrate holder 30. As such a rotation mechanism 40, for example, a known rotation mechanism including a rotation motor or the like can be used. The tilting mechanism 45 is a mechanism for tilting the rotation mechanism 40 and the substrate holder 30.

[0049] The lifting mechanism 50 is supported by a support shaft 51 extending in the vertical direction and is configured to move in the vertical direction along the support shaft 51. The lifting mechanism 50 is configured to move the substrate holder 30, the rotation mechanism 40, and the tilting mechanism 45 up and down in the vertical direction. The lifting mechanism 50 according to the present embodiment is indirectly connected to the substrate Wf via the substrate holder 30, the rotation mechanism 40, and the tilting mechanism 45, and is configured to move the substrate Wf up and down by moving these members up and down. As such a lifting mechanism 50, a known lifting mechanism including a linear actuator or the like can be used.

[0050] When performing plating treatment on the substrate Wf, the lifting mechanism 50 lowers the substrate holder 30 to immerse the substrate Wf in the plating solution Ps (as a result, the state shown in FIG. 4 is obtained).

[0051] A paddle 70 may be disposed in a region above the anode 11 and below the substrate holder 30 inside the plating tank 10. Specifically, the paddle 70 according to the present embodiment is disposed between an intermediate member 60 disposed above the anode 11 and the substrate holder 30. The paddle 70 is a "stirring member" configured to be driven by a driving device (not shown) to stir the plating solution Ps. The paddle 70 according to the present embodiment is driven alternately in the Y direction and the -Y direction in a direction parallel to the anode 11 (or the substrate Wf) as an example.

[0052] Note that the paddle 70 only needs to be disposed inside the plating tank 10 at least when stirring the plating solution Ps, and does not necessarily need to be always disposed inside the plating tank 10. For example, when the driving of the paddle 70 is stopped and the plating solution Ps is not stirred by the paddle 70, the paddle 70 can also be configured to be disposed outside the plating tank 10.

[0053] Referring to FIG. 3, the plating module 400 includes sensors 90 for detecting the state of the plating module 400. For example, these sensors 90 may include an angle sensor for detecting the rotational position (rotation angle) of the substrate Wf and a rotational speed sensor for detecting the rotational speed of the substrate Wf. Further, the sensors 90 may include a voltage sensor for detecting the voltage between the anode 11 and the substrate Wf and a current sensor for detecting the current between the anode 11 and the substrate Wf. Further, the sensors 90 may include a film thickness sensor for detecting the film thickness of the plating film formed on the substrate Wf. The data detected by these sensors is transmitted to the control module 800.

[0054] The control module 800 according to the present embodiment is configured by a microcomputer including a processor 801, a storage device 802 as a non-temporary storage medium, and the like. The control module 800 controls the operation of the plating module 400 by the operation of the processor 801 based on the instructions of the program stored in the storage device 802.

[0055] FIG. 5 is a schematic plan view of a substrate Wf according to the present embodiment. Specifically, FIG. 5 schematically shows a state in which the plated surface Wfa of the substrate Wf is viewed from above. A notch Wfc may be provided at the outer peripheral edge of the substrate Wf as a positioning mark. Alternatively, an orientation flat may be provided at the outer peripheral edge of the substrate Wf instead of the notch Wfc.

[0056] The substrate Wf according to the present embodiment has a pattern formation region Wfb which is a region where a pattern is formed. In the present embodiment, a non-pattern formation region Wfe where no pattern is formed is provided around the pattern formation region Wfb in the substrate Wf.

[0057] FIG. 20(A) is a schematic cross-sectional view showing an enlarged surface portion of the pattern formation region Wfb of the substrate Wf. Further, FIG. 20(B) is a schematic cross-sectional view illustrating a state in which a plating film (Wfd) is formed on the pattern formation region Wfb. As illustrated in FIG. 20(A), a photoresist layer Wph made of photoresist is provided in the pattern formation region Wfb of the substrate Wf.

[0058] A plurality of patterns Wpt are provided in this photoresist layer Wph. Each of the plurality of patterns Wpt is constituted by a recess or a protrusion provided in the photoresist layer Wph. Note that the photoresist layer Wph may not be provided in the non-pattern formation region Wfe of the substrate Wf, and even if the photoresist layer Wph is provided, the pattern Wpt is not provided. The pattern formation region Wfb of the substrate Wf is used as a semiconductor chip, for example, after plating treatment.

[0059] Referring to FIG. 5, the contour shape of the pattern formation region Wfb according to this embodiment is non-circular in plan view. That is, the contour (outer edge) of the pattern formation region Wfb according to this embodiment does not have a constant distance from the center of the substrate Wf. Further, the contour shape of the pattern formation region Wfb according to this embodiment is configured to appear the same before and after rotation when the substrate Wf is rotated by a "rotation symmetry angle (which has a value less than 360°)".

[0060] Taking a specific example, the pattern formation region Wfb of the substrate Wf according to this embodiment has, as an example, a cross shape in which two rectangles intersect. When the substrate Wf is rotated at least 180° clockwise from the state of FIG. 5, the contour shape of the pattern formation region Wfb appears the same before and after rotation.

[0061] In the substrate Wf illustrated in FIG. 5, as an example of the rotation symmetry angle, 180° can be used. Therefore, in this embodiment, in the following description, 180° will be used as the rotation symmetry angle. Note that when the pattern formation region Wfb has a cross shape and the shapes of the two intersecting rectangles are the same, 90° may be used as the rotation symmetry angle.

[0062] Of course, the above-mentioned value of 180° is an example of the rotation symmetry angle, and the rotation symmetry angle is not limited thereto. Taking another example, for instance, when the contour shape of the pattern formation region Wfb of the substrate Wf is a square, 90° can be used as the rotation symmetry angle (an example of this substrate Wf is illustrated in FIG. 21). For example, when the contour shape of the pattern formation region Wfb is an equilateral triangle, 120° can be used as the rotation symmetry angle. Thus, the rotation symmetry angle can take any value less than 360° according to the contour shape of the pattern formation region Wfb.

[0063] FIG. 6 is a schematic plan view of the intermediate member 60 according to the present embodiment. Referring to FIGS. 3, 4, and 6, the intermediate member 60 according to the present embodiment has, in a plan view, a hole forming region 61 in which a plurality of holes 12a through which the plating solution Ps can pass are formed, and an electric field shielding region 62 in which the holes 12a are not formed. In the present embodiment, the electric field shielding region 62 is provided around the hole forming region 61.

[0064] Further, the intermediate member 60 according to the present embodiment has, in a plan view, a contour shape of the hole forming region 61 (which is a shape of a boundary portion 65 between the hole forming region 61 and the electric field shielding region 62) corresponding to a contour shape of a pattern forming region Wfb of the substrate Wf.

[0065] In the present embodiment, "two shapes correspond" can be interpreted as that the features of the two shapes are the same. Specifically, when the two shapes look the same when visually recognized with the naked eye, it can be determined that the two shapes correspond. In the case of the present embodiment illustrated in FIGS. 5 and 6, the contour shape of the hole forming region 61 and the contour shape of the pattern forming region Wfb are the same shape.

[0066] It is preferable that the area of the hole forming region 61 and the area of the pattern forming region Wfb are the same value, but they may be different within a range of, for example, within 10%. When the areas of both are different in this way, for example, when the area of the hole forming region 61 is larger than the area of the pattern forming region Wfb, it is preferable in that it can effectively suppress a part of the pattern forming region Wfb from being hidden in the shadow of the electric field shielding region 62.

[0067] The intermediate member 60 according to the present embodiment is, as an example, constituted by an ion resistor 12 having a hole forming region 61 and an electric field shielding region 62. The ion resistor 12 is a member that serves as a resistance to ions moving inside the plating solution Ps during the plating process. The material of the intermediate member 60 (that is, the ion resistor 12) is not particularly limited, and for example, resins such as polyetheretherketone and polyvinyl chloride can be used.

[0068] Next, the plating method (plating process) according to the present embodiment will be described. FIG. 7 is an example of a flowchart of the plating method according to the present embodiment. FIG. 8 is an example of a timing chart of the plating method according to the present embodiment. Specifically, in the lower part of FIG. 8, a timing chart of the current (A) flowing between the anode 11 and the substrate Wf is illustrated, and in the upper part, a timing chart of the rotation angle (°) of the substrate Wf is illustrated.

[0069] Referring to FIG. 7, the plating method (plating process) according to the present embodiment includes a supply process (step S5), an alignment process (step S10), a first energization process (step S20), a rotation process (step S30), and a second energization process (step S40). Each step in FIG. 7 may be executed by the control process of the control module 800.

[0070] First, in the supply process according to step S5, the substrate Wf is supplied to the plating tank 10. As an example, in the present embodiment, the substrate Wf is supplied to a position above the intermediate member 60 in the plating tank 10 and not in contact with the intermediate member 60. Specifically, the control module 800 controls the lifting mechanism 50, for example, to lower the substrate holder 30 holding the substrate Wf, thereby disposing the substrate Wf at a position above the intermediate member 60 in the plating tank 10 and not in contact with the intermediate member 60.

[0071] Next, in the alignment process according to step S10, the position (rotation position) of the substrate Wf is adjusted so that the contour shape of the pattern formation region Wfb of the substrate Wf and the contour shape of the hole formation region 61 of the intermediate member 60 are spatially aligned. For reference, FIG. 9 illustrates an image diagram of a state where the contour shape of the pattern formation region Wfb is aligned with the contour shape of the hole formation region 61.

[0072] Note that the state where the contour shape of the pattern formation region Wfb and the contour shape of the hole formation region 61 of the intermediate member 60 are spatially aligned means that the pattern formation region Wfb and the hole formation region 61 do not contact each other, but when the contour shape of the pattern formation region Wfb is projected downward, this projected shape substantially coincides with the contour shape of the hole formation region 61.

[0073] Specifically, in step S10, the control module 800 according to the present embodiment controls the rotation mechanism 40 to rotate the substrate holder 30, thereby rotating the substrate Wf to align the contour shape of the pattern formation region Wfb of the substrate Wf with the contour shape of the hole formation region 61.

[0074] In the following description, the rotational position of the substrate Wf where the contour shape of the pattern formation region Wfb is aligned with the contour shape of the hole formation region 61 may be referred to as the "reference rotational position" of the substrate Wf.

[0075] Next, the first energization process according to step S20 is executed. In this first energization process, while causing the substrate Wf to perform a "rocking rotational motion", the anode 11 and the substrate Wf are energized for a predetermined time. This first energization process corresponds to the period "from time 0 (sec) to time t1 (sec)" in FIG. 8. For reference, FIG. 10 shows a schematic diagram illustrating the state where the substrate Wf is performing a rocking rotational motion.

[0076] Here, the "rocking rotational motion" refers to a rotational motion in which the substrate Wf is rotated by a first angle (α1) in a first rotational direction (Rt1) and the substrate Wf is rotated by a second angle (α2) in a second rotational direction (Rt2) opposite to the first rotational direction, at least once, with the state where the contour shape of the pattern formation region Wfb is aligned with the contour shape of the hole formation region 61 of the intermediate member 60 as the center (that is, with the reference rotational position as the center) (see FIG. 10).

[0077] In the present embodiment illustrated in FIG. 8, during the rocking rotational movement, the substrate Wf rotates in the first rotational direction and the second rotational direction a plurality of times. Also, in the present embodiment, as an example, the first angle and the second angle are the same value as each other. However, it is not limited to this configuration. For example, the first angle and the second angle may be different values from each other.

[0078] The specific values of the upper limit values of the first angle and the second angle are not particularly limited. However, as an example, an angle of 45° or less, specifically an angle of 30° or less, and more specifically an angle of 10° or less can be used. According to this configuration, the substrate Wf can perform a rocking rotational movement in the vicinity of the reference rotational position.

[0079] Also, the specific values of the lower limit values of the first angle and the second angle are not particularly limited as long as the angle is greater than 0°. As an example of the lower limit values of the first angle and the second angle, an angle of 1° or more, specifically an angle of 3° or more, and more specifically an angle of 5° or more can be used.

[0080] Note that in step S20, the control module 800 may cause the substrate Wf to perform a rocking rotational movement by controlling the rotation mechanism 40. Also, the control module 800 may energize the anode 11 and the substrate Wf by controlling the energizing device 18.

[0081] Also, in FIG. 8, the rocking rotational movement is represented by a triangular waveform, but it is not limited to this. For example, the rocking rotational movement may be represented by a sine wave waveform or the like.

[0082] By executing the first energization process as described above, a plating film Wfd is formed on at least the pattern formation region Wfb of the plating surface Wfa of the substrate Wf (see FIG. 20(B)).

[0083] The execution period of the first energization process is not particularly limited. For example, a value selected from the range of several seconds to several hundred seconds can be used. To give an example, for instance, a value selected from the range of 5 seconds to 500 seconds may be used. Further, when the substrate Wf rotates multiple times in the rocking rotational motion, the specific value of this number of times is not particularly limited. For example, a value selected from the range of several times to several hundred times can be used. To give an example, for instance, a value selected from the range of 2 times to 200 times may be used.

[0084] Next, the rotation process according to step S30 in FIG. 7 is executed. In this rotation process, with the energization to the anode 11 and the substrate Wf stopped, the substrate Wf is rotated by the "rotation symmetry angle (in this embodiment, 180° as an example)". This rotation process corresponds to the period "between time t1 and time t2" in FIG. 8.

[0085] Specifically, in step S30, the control module 800 according to this embodiment controls the rotation mechanism 40 to rotate the substrate Wf by the rotation symmetry angle with the energization to the anode 11 and the substrate Wf stopped.

[0086] By stopping the energization to the anode 11 and the substrate Wf in the rotation process, it is possible to suppress the formation of a plating film in the pattern formation region Wfb in a state where the rotation position of the substrate Wf is greatly deviated from the reference rotation position.

[0087] Next, the second energization process according to step S40 in FIG. 7 is executed. In this second energization process, while causing the substrate Wf to perform a rocking rotational motion (that is, in a state where the substrate Wf is performing a rocking rotational motion), the anode 11 and the substrate Wf are energized for a predetermined time. This second energization process corresponds to the period "between time t2 and time t3" in FIG. 8. Note that the predetermined time according to step S40 and the predetermined time according to step S20 may be the same value or different values.

[0088] Specifically, in step S40, the control module 800 according to the present embodiment causes the substrate Wf to perform a rocking rotational movement by controlling the rotation mechanism 40. Further, the control module 800 energizes the anode 11 and the substrate Wf by controlling the energizing device 18.

[0089] By executing this second energization process, a plating film is further formed on at least the pattern formation region Wfb of the plated surface Wfa of the substrate Wf.

[0090] Note that the execution period of the second energization process is not particularly limited. For example, a value selected from the range of several seconds to several hundred seconds can be used. For example, a value selected from the range of 5 seconds to 500 seconds may be used. Further, when the substrate Wf rotates a plurality of times during the rocking rotational movement in the second energization process, the specific value of this number of rotations is not particularly limited. For example, a value selected from the range of several times to several hundred times can be used. For example, a value selected from the range of 2 times to 200 times may be used.

[0091] The plating method according to the present embodiment may further execute at least once a "series of processes" including the rotation process (step S30) and the second energization process (step S40) after the execution of the above-described second energization process. Specifically, in FIG. 8, after time t3 is an example of a timing chart of this "series of processes".

[0092] Specifically, "time t3 to t4" in FIG. 8 corresponds to the second rotation process, and "time t4 to t5" corresponds to the second second energization process. Further, "time t5 to t6" corresponds to the third rotation process, and "time t6 to t7" corresponds to the third second energization process. That is, in the timing chart of FIG. 8, the "series of processes" is executed twice after the first second energization process.

[0093] Note that the execution time of the first energization process and the execution time of the second energization process may be the same value or different values. Also, the period during which the rocking rotational motion is performed in the second energization process (referred to as "period (T1)") may be the same value or different values among the second energization processes executed multiple times. Further, the "amplitude (Am) of the rocking rotational motion" may be the same value or different values among the multiple second energization processes. Note that the specific value of the period (T1) is not particularly limited, and for example, a value within the range of several seconds to several hundred seconds may be used.

[0094] Of course, the example described in FIG. 8 is merely an example of the plating method. For example, the series of processes may be executed only once, or may be executed three or more times. Alternatively, the series of processes may not be executed at all.

[0095] Note that the plating process by the above-described plating method may be executed until the film thickness of the plating film formed on the substrate Wf reaches a preset target value. In this case, the above-described series of processes may be repeatedly executed until the film thickness reaches the target value.

[0096] Also, as illustrated in FIG. 8, in the present embodiment, as an example, when the rotation process is executed multiple times, the rotation direction of the substrate Wf in the rotation process executed at an arbitrary time and the rotation direction of the substrate Wf in the next rotation process are in opposite directions.

[0097] That is, the rotation direction of the substrate Wf at the first rotation process and the rotation direction of the substrate Wf at the second rotation process are in opposite directions. Similarly, the rotation direction of the substrate Wf at the second rotation process and the rotation direction of the substrate Wf at the third rotation process are in opposite directions. Also, in this case, the substrate Wf may rotate in the same direction at the "n-th" rotation process when the value of "rotation angle of the substrate Wf × n" reaches 360°.

[0098] However, when the rotation process is executed multiple times, the rotation direction of the substrate Wf is not limited to the above-described configuration. For example, as illustrated in FIG. 15, when the rotation process is executed multiple times, the rotation direction of the substrate Wf in the rotation process executed at an arbitrary time and the rotation direction of the substrate Wf in the next rotation process may be the same direction.

[0099] Also, in the embodiment illustrated in FIG. 8, the rotation speed (° / sec) of the substrate Wf in the rocking rotation motion and the rotation speed of the substrate Wf in the rotation process are the same value. However, the present invention is not limited to this configuration.

[0100] For example, as illustrated in FIG. 16, the rotation speed (° / sec) of the substrate Wf in the rocking rotation motion and the rotation speed of the substrate Wf in the rotation process may be different values. Also, in this case, as illustrated in FIG. 16, for example, the rotation speed of the substrate Wf in the rocking rotation motion may be slower than the rotation speed of the substrate Wf in the rotation process.

[0101] Subsequently, the main operational effects of the present embodiment will be described. FIG. 18 is a schematic plan view of an intermediate member 6000 according to a comparative example. FIG. 19 is a schematic plan view for explaining the film thickness distribution of the substrate Wf.

[0102] Referring to FIG. 18, the intermediate member 6000 according to the comparative example is different from the intermediate member 60 according to the present embodiment illustrated in FIG. 6 in that the contour shape of the hole formation region 61 is circular.

[0103] When such an intermediate member 6000 according to the comparative example is used, since the contour shape of the hole formation region 61 of the intermediate member 6000 does not correspond to the contour shape of the pattern formation region Wfb of the substrate Wf, for example, depending on the shape of the pattern formation region Wfb of the substrate Wf, a part of the pattern formation region Wfb may be hidden in the shadow of the electric field shielding region 62 of the intermediate member 6000. In this case, it is difficult to achieve uniformization of the film thickness of the plating film formed on the pattern formation region Wfb of the substrate Wf.

[0104] On the other hand, according to the present embodiment, as the intermediate member 60, one in which the contour shape of the hole forming region 61 corresponds to the contour shape of the pattern forming region Wfb of the substrate Wf is used. Therefore, it is possible to suppress the pattern forming region Wfb of the substrate Wf from being hidden in the shadow of the electric field shielding region 62 of the intermediate member 60. Thereby, it is possible to make the film thickness of the plating film formed in the pattern forming region Wfb of the substrate Wf uniform.

[0105] In addition, when the intermediate member 6000 according to the comparative example is used, the film thickness of the outer edge portion of the pattern forming region Wfb of the substrate Wf tends to be thicker than the film thickness of the region inside the outer edge portion of the pattern forming region Wfb. As a result, referring to FIG. 19, there is a tendency for a large difference in film thickness between the point P1 and the point P2 at a radius position smaller than this point P1. Specifically, the film thickness at the point P1 tends to be thicker than that at the point P2.

[0106] On the other hand, according to the present embodiment, as the intermediate member 60, one in which the contour shape of the hole forming region 61 corresponds to the contour shape of the pattern forming region Wfb of the substrate Wf is used. Therefore, the difference in film thickness between the point P1 and the point P2 can be made smaller compared to the comparative example.

[0107] Furthermore, according to the present embodiment, in the first energization process and the second energization process, since the substrate Wf is performing a rocking rotational movement, the effects described below can also be achieved.

[0108] FIG. 11 is a schematic diagram for explaining the action and effect of the rocking rotational motion. Specifically, the upper diagram (No1) in FIG. 11 shows an example of the film thickness distribution when the substrate Wf does not perform a rocking rotational motion (specifically, when the rotation of the substrate Wf has stopped) and the anode 11 and the substrate Wf are energized in the first energization process and the second energization process. Note that No1 in FIG. 11 shows the film thickness distribution of the portion along the virtual line L1 illustrated in FIG. 5. On the other hand, the lower part (No2) of FIG. 11 shows an example of the film thickness distribution (the film thickness distribution of the portion along the virtual line L1) when the substrate Wf performs a rocking rotational motion and the anode 11 and the substrate Wf are energized in the first energization process and the second energization process.

[0109] As can be seen from No1 in FIG. 11, in the case of the comparative example, the film thickness of the portion of the substrate Wf corresponding to the boundary portion 65 of the intermediate member 60 (specifically, the regions R1 and R2 in FIG. 5) tends to be particularly thick.

[0110] On the other hand, when the substrate Wf is rocked and rotated in the first energization process or the second energization process, the plating process is performed on the substrate Wf while the position of the boundary portion 65 of the intermediate member 60 is shifted left and right in plan view. As a result, due to the electric field shielding effect of the electric field shielding region 62 of the intermediate member 60, as illustrated in No2 of FIG. 11, the film thickness of the portions of the regions R1 and R2 can be kept low. As a result, the film thickness of the plating film formed in the pattern formation region Wfb of the substrate Wf can be effectively made uniform.

[0111] Further, according to the present embodiment, since the rotation process is executed after the first energization process and then the second energization process is executed, the effects described below can be achieved.

[0112] Specifically, there may be a case where the center positions are slightly misaligned between the substrate Wf held by the substrate holder 30 and the intermediate member 60, or a case where the parallelism is slightly misaligned between the substrate Wf and the intermediate member 60. When the second energization process is executed without executing the rotation process after the first energization process in such a state (that is, when the energization process is executed for a long time), the uniformity of the film thickness may deteriorate due to the influence of such misalignment of the center position or misalignment of the parallelism.

[0113] On the other hand, according to the present embodiment, since the plating process can be performed on the substrate Wf in the second energization process after rotating the substrate Wf by the rotationally symmetric angle in the rotation process, it is possible to reduce the deterioration of the film thickness uniformity caused by such misalignment of the center position or misalignment of the parallelism. Also in this regard, according to the present embodiment, the uniformity of the film thickness can be effectively achieved.

[0114] (Modification Example 1) In the above-described embodiment, instead of the intermediate member 60, an intermediate member 60A described below may be used. FIG. 12 is a schematic cross-sectional view of the intermediate member 60A according to Modification Example 1 of the embodiment. The intermediate member 60A according to this modification includes an ion resistor 12 having a plurality of holes 12a and an electric field shielding member 63 disposed above the ion resistor 12.

[0115] In this modification, the contour shape of the region where the plurality of holes 12a of the ion resistor 12 are formed does not have to correspond to the contour shape of the pattern formation region Wfb of the substrate Wf. To give a specific example, the contour shape of the region where the plurality of holes 12a of the ion resistor 12 according to this modification are formed may be circular in plan view.

[0116] FIG. 13 is a schematic plan view of the electric field shielding member 63 according to this modification. Referring to FIGS. 12 and 13, the electric field shielding member 63 according to this modification has an opening 66. In this case, the above-described electric field shielding region 62 is constituted by the region around the opening 66 of the electric field shielding member 63.

[0117] Further, the aforementioned hole formation region 61 is constituted by a region in which a plurality of holes 12a of the ion resistor 12 are formed, which is located inside the opening 66 of the electric field shielding member 63 in a plan view (see FIG. 12). As a result, the contour shape (the shape of the boundary portion 65) of the aforementioned hole formation region 61 is constituted by the contour shape of the opening 66 of the electric field shielding member 63 (see FIGS. 12 and 13).

[0118] In this modification as well, the shape of the intermediate member 60A having the ion resistor 12 and the electric field shielding member 63 when viewed from above is the same as the shape of the intermediate member 60 illustrated in FIG. 6.

[0119] Even when the plating apparatus 1000 includes the intermediate member 60A according to this modification, the same operational effects as those of the aforementioned embodiment can be achieved.

[0120] In this modification, although the ion resistor 12 and the electric field shielding member 63 are in contact with each other, the present invention is not limited to this configuration. The ion resistor 12 and the electric field shielding member 63 may not be in contact with each other, and a space (a space in which the plating solution Ps exists) may be formed between the ion resistor 12 and the electric field shielding member 63.

[0121] Further, this modification may be configured such that the relative position of the electric field shielding member 63 in the horizontal plane inside the plating tank 10 can be changed. FIG. 14 is a schematic diagram for explaining an example of a configuration in which the position of the electric field shielding member 63 can be changed. As illustrated in FIG. 14, the electric field shielding member 63 may be connected to the moving device 80 via the engaging member 81.

[0122] The engaging member 81 is configured to support the electric field shielding member 63 and connect the moving device 80 and the electric field shielding member 63. Such an engaging member 81 may be constituted by, for example, a cylindrical member (or a plurality of rod members) arranged to pass through the gap between the substrate holder 30 and the plating tank 10. When the engaging member 81 is constituted by a cylindrical member, at least one opening 82 for the plating solution to pass between the inside and the outside of the engaging member 81 may be provided in the engaging member 81 as required.

[0123] The moving device 80 is configured to move the engaging member 81 in an arbitrary direction in a horizontal plane direction (direction in the X - Y plane), for example, in response to an instruction from the control module 800. As an example, the moving device 80 may include a cylinder linear motion mechanism configured to move the engaging member 81 in the X direction and the - X direction, and a cylinder linear motion mechanism configured to move the engaging member 81 in the Y direction and the - Y direction. For example, the control module 800 may move the moving device 80 according to an instruction from a user of the plating device 1000.

[0124] According to the above configuration, even if the position of the electric field shielding member 63 in the horizontal plane is displaced from the desired position by a predetermined distance (for example, about several millimeters), the moving device 80 can move the electric field shielding member 63 horizontally by a predetermined distance to the desired position. Thereby, the alignment between the hole forming region 61 of the electric field shielding member 63 and the pattern forming region Wfb of the substrate Wf can be easily performed.

[0125] The adjustment of the position of the electric field shielding member 63 using this moving device 80 may be performed, for example, in the above - mentioned "alignment process". That is, in this case, the alignment process may include aligning the hole forming region 61 of the electric field shielding member 63 and the pattern forming region Wfb of the substrate Wf not only by rotating the substrate Wf but also by moving the electric field shielding member 63 in the horizontal plane direction.

[0126] (Modification 2) In the above-described embodiments and Modification 1, the plating method may be configured not to include the rotation process (Step S30) and the second energization process (Step S40). That is, in this case, the plating method is constituted by the supply process (Step S5), the alignment process (Step S10), and the first energization process (Step S20). An example of the timing chart of the first energization process in this case is illustrated in FIG. 17.

[0127] This modification is preferably used, for example, when the contour shape of the pattern formation region Wfb of the substrate Wf does not have a "rotation symmetry angle of less than 360°".

[0128] Also in this modification, since the alignment process and the first energization process are executed, when performing the plating process on the substrate Wf, while causing the substrate Wf to perform a rocking rotational movement around the state where the contour shape of the pattern formation region Wfb corresponds to the contour shape of the hole formation region 61, it is possible to energize the anode 11 and the substrate Wf. Thereby, the thickness uniformity can be achieved.

[0129] As described above in detail for the embodiments and modifications of the present invention, the present invention is not limited to such specific embodiments and modifications, and various further modifications and changes are possible within the scope of the gist of the present invention.

Explanation of Reference Numerals

[0130] 10 Plating tank 11 Anode 12 Ion resistor 12a Hole 60 Intermediate member 61 Hole formation region 62 Electric field shielding region 63 Electric field shielding member 800 Control module 1000 Plating apparatus Ps Plating solution Wf Substrate Wfb Pattern formation region Wpt Pattern

Claims

1. a supply process for supplying a substrate to a plating tank in which an anode and an intermediate member are disposed, the intermediate member being disposed between the anode and the substrate supplied to the plating tank, the substrate being supplied to a location not in contact with the intermediate member, the substrate having a pattern-forming region in which a plurality of patterns are formed, the outline shape of the pattern-forming region being non-circular, the intermediate member having, in a plan view, a hole-forming region in which a plurality of holes through which a plating solution can pass formed, and an electric field shielding region disposed around the hole-forming region, the outline shape of the hole-forming region corresponding to the outline shape of the pattern-forming region; an alignment process for adjusting a position of the substrate so that a contour shape of the pattern formation region and a contour shape of the hole formation region are spatially aligned; a first current flow process for passing current through the anode and the substrate while causing the substrate to perform an oscillatory rotational motion, wherein during the oscillatory rotational motion, the substrate rotates a first angle in a first rotational direction around a state in which the contour shape of the pattern formation region is aligned with the contour shape of the hole formation region, and rotates a second angle in a second rotational direction opposite to the first rotational direction, at least once.

2. 2. The plating method of claim 1, wherein the first angle is less than or equal to 45 degrees and the second angle is less than or equal to 45 degrees.

3. 2. The plating method according to claim 1, wherein the contour shape of the pattern formation region is configured to appear the same before and after rotation when the substrate is rotated through a rotational symmetry angle less than 360°.

4. The plating method includes: a rotation process in which, after the first current application process, the substrate is rotated by the rotational symmetry angle while current application to the anode and the substrate is stopped; The plating method according to claim 3 , further comprising a second current application process, after the rotation process, of applying current to the anode and the substrate while causing the substrate to perform the oscillatory rotation motion.

5. The plating method according to claim 4 , further comprising the step of performing a series of processes including the rotation process and the second current flow process at least once after the second current flow process is performed.

6. The plating method according to claim 5 , wherein the series of steps is performed a plurality of times.

7. 7. The plating method according to claim 6, wherein, in the rotation process that is performed a plurality of times, the rotation direction of the substrate in the rotation process performed at any given time is opposite to the rotation direction of the substrate in the next rotation process performed.

8. 7. The plating method according to claim 6, wherein, in the rotation process that is performed a plurality of times, the rotation direction of the substrate in the rotation process performed at any given time is the same as the rotation direction of the substrate in the next rotation process that is performed.

9. 5. The plating method according to claim 4, wherein a rotation speed of the substrate during the oscillatory rotation motion and a rotation speed of the substrate during the rotation process are the same value.

10. The plating method according to claim 4 , wherein a rotation speed of the substrate during the oscillatory rotation motion and a rotation speed of the substrate during the rotation process are different values.

11. The plating method according to claim 10 , wherein a rotation speed of the substrate during the oscillatory rotation motion is slower than a rotation speed of the substrate during the rotation process.

12. The plating method according to claim 1 , wherein the intermediate member has an ion resistor having the hole formation region and the electric field shielding region.

13. the intermediate member has an ion resistor in which the plurality of holes are formed, and an electric field shielding member having an opening and disposed above the ion resistor, the electric field shielding region is configured by a region around the opening of the electric field shielding member, the hole formation region is constituted by a region of the ion resistor located inside the opening of the electric field shielding member in a plan view, in which the plurality of holes are formed, The plating method according to claim 1 , wherein the contour shape of the hole formation region is defined by the contour of the opening of the electric field shielding member.

14. A plating apparatus comprising a control module configured to execute the supply process, the alignment process, and the first current application process according to claim 1 .

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