Coating device

Abstract

Provided is a plating device capable of improving the uniformity of the thickness of a plating film formed on a plating target. The plating device includes a resistor body having a first resistor member and a second resistor member disposed between the first resistor member and a substrate holder or between the first resistor member and an anode. The first resistor member has a plurality of first through holes that are open on the substrate holder side and the anode side. At least a portion of the plurality of first through holes overlaps the second resistor member when viewed from the substrate side to the anode side, and the second resistor member is configured to be variable in distance from the first resistor member.

Description

Technical Field

[0001] This application relates to a plating apparatus. Background Technology

[0002] As an example of a plating apparatus using electroplating, a so-called immersion plating apparatus is known in which a substrate (e.g., a semiconductor wafer) and an anode are positioned horizontally opposite each other (see, for example, Patent Document 1). Another example of a plating apparatus using electroplating is a cup-type plating apparatus (see, for example, Patent Document 2). In the cup-type plating apparatus, a substrate held by a substrate holder is immersed in a plating solution with the plating surface facing downwards. A voltage is applied between the substrate and the anode, causing a conductive film (plating film) to deposit on the surface of the substrate.

[0003] In such plating apparatuses, the substrate typically has electrical contacts at its periphery. Due to varying distances from these contacts, a potential difference arises between the periphery and the center of the substrate during the plating process, potentially causing deviations in the plating current. Therefore, it is known that, in order to improve the uniformity of the thickness of the coating formed on the substrate, a resistive element for adjusting the electric field is placed between the substrate and the anode. Furthermore, to allow for more flexible adjustment of the electric field, a plating apparatus has been proposed that allows for a variable size of the orifice of the resistive element (see Patent Document 3).

[0004] Patent Document 1: Japanese Patent No. 7462125

[0005] Patent Document 2: Japanese Patent No. 7079388

[0006] Patent Document 3: Japanese Patent No. 7204060

[0007] In plating apparatuses, besides the distance to electrical contacts, the thickness of the coating can also deviate due to the resist pattern formed on the substrate. That is, if the plated surface of the substrate includes areas where resist openings are not formed (non-opening areas), the plating current will not flow through these non-opening areas, and the current will concentrate at the periphery of these areas, resulting in a thicker coating. As a specific example, when resist openings are formed only in a roughly cross-shaped area on the substrate, no current flows through the areas outside the cross, potentially compromising the uniformity of the coating thickness. Here, for example, in Patent Document 1, an anode cover capable of adjusting the size of the anode opening is used to adjust the electric field between the anode and the substrate. However, existing structures are designed to address coating thickness deviations caused by the structure of the plating apparatus, such as electrical contacts, and sometimes cannot adequately address coating thickness deviations caused by the resist pattern on the substrate. Alternatively, virtual openings can be created in non-opening areas to achieve uniform coating thickness. However, this would require processing to create the virtual openings and would result in unnecessary coating at the virtual openings, thus increasing the cost of the coating process. Summary of the Invention

[0008] The present invention was made in view of the above-mentioned problems. One of its objectives is to provide a coating apparatus capable of improving the uniformity of the thickness of the coating formed on the object to be coated.

[0009] According to one embodiment, a plating apparatus is provided, comprising: a plating tank; a substrate holder configured to hold a substrate; an anode disposed in the plating tank opposite to the substrate held by the substrate holder; and a resistor disposed between the substrate holder and the anode for adjusting an electric field. The resistor comprises: a first resistive member and a second resistive member disposed between the first resistive member and the substrate holder or between the first resistive member and the anode. The first resistive member has a plurality of first through holes opening on the substrate holder side and the anode side. At least a portion of the plurality of first through holes overlaps with the second resistive member in such a way that the anode cannot be visually identified when viewed from the substrate side. The second resistive member is configured to be at a variable distance from the first resistive member. Attached Figure Description

[0010] Figure 1 This is a perspective view showing the overall structure of the plating apparatus of this embodiment.

[0011] Figure 2 This is a top view showing the overall structure of the plating apparatus of this embodiment.

[0012] Figure 3This is a longitudinal sectional view schematically illustrating the structure of the plating module in this embodiment.

[0013] Figure 4 This is a top view of the first resistor component in this embodiment.

[0014] Figure 5 This is a top view of the second resistor component in this embodiment.

[0015] Figure 6 This is a longitudinal sectional view of a resistor body schematically showing the state in which the first resistor component and the second resistor component are separated.

[0016] Figure 7 It is a longitudinal sectional view of a resistor body schematically showing the contact state between the first resistor component and the second resistor component.

[0017] Figure 8 This is a flowchart illustrating an example of a method for setting the action scheme of the resistor, anode cover, and shield based on the control module.

[0018] Figure 9 This is a schematic diagram illustrating the resist pattern formed on the plated surface of a substrate in one embodiment.

[0019] Figure 10 This is a flowchart illustrating an example of a method for setting the action scheme of the resistive element, anode cover, and shielding element in the plating process based on the control module.

[0020] Figure 11 It is a longitudinal sectional view of the resistor body schematically showing the state in which the first resistor component and the second resistor component are separated in the first modified example.

[0021] Figure 12 It is a longitudinal sectional view of the resistor body schematically showing the state of contact between the first resistor component and the second resistor component in the first modified example.

[0022] Figure 13 It is a longitudinal sectional view schematically shown by enlarging the resistive element in the second modified example, in which the first resistive element and the second resistive element are separated by a first distance.

[0023] Figure 14 It is a longitudinal sectional view schematically shown by enlarging the resistive element in the second modified example, in which the first resistive element and the second resistive element are separated by a second distance.

[0024] Figure 15 It is a longitudinal sectional view schematically shown by enlarging the resistive element in the second modified example, in which the first resistive element and the second resistive element are separated by a third distance. Detailed Implementation

[0025] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings described below, the same or equivalent constituent elements are labeled with the same reference numerals and repeated descriptions are omitted.

[0026] <Overall Structure of the Plating Equipment>

[0027] Figure 1 This is a perspective view showing the overall structure of the plating apparatus of this embodiment. Figure 2 This is a top view showing the overall structure of the plating apparatus of this embodiment. (e.g.) Figure 1 and Figure 2 As shown, the plating apparatus 1000 includes: a loading port 100, a handling robot 110, an alignment device 120, a pre-wetting module 200, a pre-immersion module 300, a plating module 400, a cleaning module 500, a rotary rinsing and drying device 600, a handling device 700, and a control module 800.

[0028] The loading port 100 is a module used to load substrates stored in a FOUP (not shown) into the plating apparatus 1000, or to remove substrates from the plating apparatus 1000 into the FOUP. In this embodiment, four loading ports 100 are arranged side by side in the horizontal direction, but the number and arrangement of the loading ports 100 are arbitrary. The handling robot 110 is a robot for handling substrates, configured to exchange substrates between the loading ports 100, the alignment device 120, and the handling device 700. When exchanging substrates between the handling robot 110 and the handling device 700, the handling robot 110 and the handling device 700 can exchange substrates via a temporary stage (not shown).

[0029] Aligner 120 is a module used to align the orientation plane, notch, and other positions of the substrate with a predetermined direction. In this embodiment, two alignment devices 120 are arranged side by side in the horizontal direction, but the number and arrangement of alignment devices 120 are arbitrary. Pre-wetting module 200 uses a treatment liquid such as pure water or degassed water to wet the substrate surface to be plated before plating, thereby replacing the air inside the pattern formed on the substrate surface with the treatment liquid. Pre-wetting module 200 is configured to perform a pre-wetting process, which facilitates the supply of plating liquid to the inside of the pattern by replacing the treatment liquid inside the pattern with plating liquid during plating. In this embodiment, two pre-wetting modules 200 are arranged side by side in the vertical direction, but the number and arrangement of pre-wetting modules 200 are arbitrary.

[0030] The pre-impregnation module 300 is configured to perform a pre-impregnation process, which involves, for example, etching away high-resistivity oxide films such as those on the seed layer surface of the substrate to be plated before plating with a treatment solution such as sulfuric acid or hydrochloric acid, and cleaning or activating the surface of the substrate to be plated. In this embodiment, two pre-impregnation modules 300 are arranged side-by-side in the vertical direction, but the number and arrangement of the pre-impregnation modules 300 are arbitrary. The plating module 400 performs the plating process on the substrate. In this embodiment, there are two sets of twelve plating modules 400, three arranged side-by-side in the vertical direction and four arranged side-by-side in the horizontal direction, for a total of twenty-four plating modules 400, but the number and arrangement of the plating modules 400 are arbitrary.

[0031] The cleaning module 500 is configured to clean the substrate to remove residual plating solution or the like after plating. In this 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 rotary rinsing and drying device 600 is a module for rotating and drying the cleaned substrate at high speed. In this embodiment, two rotary rinsing and drying devices are arranged side-by-side in the vertical direction, but the number and arrangement of the rotary rinsing and drying devices are arbitrary. The conveying device 700 is a device for conveying the substrate between multiple modules within the plating apparatus 1000. The control module 800 is configured to control multiple modules of the plating apparatus 1000, and can be configured, for example, by a general-purpose computer or a dedicated computer equipped with an input / output interface for the operator.

[0032] An example of a series of plating processes based on the plating apparatus 1000 will be described. First, a substrate stored in a box is moved into the loading port 100. Next, a handling robot 110 removes the substrate from the box in the loading port 100 and transports the substrate to the aligner 120. The aligner 120 aligns the orientation plane, notches, and other positions of the substrate with a predetermined direction. The handling robot 110 then transfers the substrate, which has been aligned by the aligner 120, to the handling device 700.

[0033] The transport device 700 transports the substrate received from the transport robot 110 to the pre-humidification module 200. The pre-humidification module 200 performs a pre-humidification treatment on the substrate. The transport device 700 then transports the pre-humidified substrate to the pre-impregnation module 300. The pre-impregnation module 300 performs a pre-impregnation treatment on the substrate. The transport device 700 then transports the pre-impregnation treated substrate to the plating module 400. The plating module 400 performs a plating treatment on the substrate.

[0034] The transport device 700 transports the plated substrate to the cleaning module 500. The cleaning module 500 cleans the substrate. The transport device 700 then transports the cleaned substrate to the rotary rinsing and drying device 600. The rotary rinsing and drying device 600 dries the substrate. The transport device 700 then transfers the dried substrate to the transport robot 110. The transport robot 110 transports the substrate received from the transport device 700 to a cassette in the loading port 100. Finally, the cassette containing the substrate is removed from the loading port 100.

[0035] <Structure of the plating module>

[0036] Next, the structure of the plating module 400 will be described. Since the twenty-four plating modules 400 in this embodiment have the same structure, only one plating module 400 will be described.

[0037] Figure 3 This is a longitudinal sectional view schematically illustrating the structure of the plating module 400 in this embodiment. (See attached image.) Figure 3 As shown, the plating module 400 includes a plating tank 410 for containing plating liquid. The plating tank 410 is configured to include a cylindrical inner tank with an opening at the top and an outer tank (not shown) disposed around the inner tank to store plating liquid overflowing from the upper edge of the inner tank.

[0038] The plating module 400 includes a substrate holder 440 for holding the substrate Wf with the plating surface Wf-a facing downwards. The substrate holder 440 also includes a power supply contact (not shown) for supplying power to the substrate Wf from a power source (not shown). In one embodiment, the power supply contact contacts the outer edge of the substrate Wf, supplying power to the outer edge. The plating module 400 includes a lifting mechanism 442 for raising and lowering the substrate holder 440. In another embodiment, the plating module 400 includes a rotation mechanism 448 for rotating the substrate holder 440 about a vertical axis. The lifting mechanism 442 and the rotation mechanism 448 can be implemented using known mechanisms such as motors.

[0039] The plating module 400 includes a diaphragm 420 that divides the interior of the plating tank 410 vertically. The interior of the plating tank 410 is divided into a cathode region 422 and an anode region 424 by the diaphragm 420. The cathode region 422 and the anode region 424 are respectively filled with plating solution. In this embodiment, an example with the diaphragm 420 is shown, but the diaphragm 420 may not be provided.

[0040] An anode 430 is disposed on the bottom surface of the anode region 424 of the plating tank 410. As an example, the anode 430 is a circular component with a surface area approximately equal in size to that of the substrate Wf. Additionally, an anode cover 426 for adjusting the electric field between the anode 430 and the substrate Wf is disposed in the anode region 424. The anode cover 426 is disposed near the anode 430 and is, for example, a generally plate-shaped electric field shield made of a dielectric material. The anode cover 426 has an opening through which current flowing between the anode 430 and the substrate Wf passes. In this embodiment, the anode cover 426 is configured to allow for changing the opening size, which is adjusted by the control module 800. Here, the opening size refers to the diameter when the opening is circular, and the length of one side or the longest opening width when the opening is polygonal. Furthermore, the changing of the opening size in the anode cover 426 can employ a known mechanism. In this embodiment, an example with an anode cover 426 is shown, but the anode cover 426 may not be provided. Furthermore, the aforementioned diaphragm 420 can also be disposed in the opening of the anode cover 426.

[0041] The plating module 400 includes a resistor 450 disposed between the substrate Wf and the anode 430. In this embodiment, the resistor 450 is disposed in the cathode region 422. The resistor 450 is a component used to adjust the electric field to achieve uniform plating processing on the plating surface Wf-a of the substrate Wf. Since the resistor 450 increases the resistance between the anode 430 and the substrate Wf, making it difficult for the electric field to spread, the thickness distribution of the plating film formed on the plating surface Wf-a of the substrate Wf can be made uniform. Therefore, if the distance between the substrate Wf and the resistor 450 increases, the space in which the electric field between the substrate Wf and the resistor 450 can spread increases. Therefore, the resistor 450 is preferably disposed near the plating surface Wf-a of the substrate Wf. The resistor 450 will be described in detail later.

[0042] Additionally, the plating module 400 includes: a blade 480 disposed between a substrate Wf held by a substrate holder 440 and a resistor 450, and a blade stirring mechanism 482 for moving the blade 480 within the plating solution to stir the plating solution. The blade 480 is not limited, but can be, for example, a plate component with a large number of honeycomb-shaped holes. The blade stirring mechanism can be implemented using a known mechanism such as a motor. The blade stirring mechanism 482 is configured to reciprocate the blade 480 along the plating surface Wf-a of the substrate Wf, thereby stirring the plating solution near the plating surface Wf-a of the substrate Wf. However, it is not limited to the above example; as an example, the blade stirring mechanism 482 may also be configured to reciprocate the blade 480 perpendicular to the plating surface Wf-a. Furthermore, in this embodiment, an example is shown where the blade 480 and blade stirring mechanism 482 are provided, but the blade 480 and blade stirring mechanism 482 may not be provided.

[0043] Additionally, a sensor 460 is provided in the cathode region 422 for detecting parameters related to the coating on the plated surface Wf-a formed on the substrate Wf. In this embodiment, the parameters related to the coating refer to physical quantities used to infer the film thickness or the formation rate of the coating. The sensor 460 is configured to face the plated surface Wf-a. In this embodiment, the sensor 460 is configured to be movable in a manner that changes the detection position along the radial direction of the substrate Wf. However, it is not limited to the above example, and multiple sensors 460 facing the plated surface Wf-a may be provided. In addition, in one embodiment, the detection end of the sensor 460 is disposed inside the resistor 450 (within the groove 454). However, it is not limited to the above example, and the sensor 460 may be disposed at other locations outside the resistor 450, for example.

[0044] The detection signal from sensor 460 is input to control module 800. In this embodiment, a potential sensor having a detection electrode (not shown) is used as sensor 460. Furthermore, the detection electrode of sensor 460 can be configured to face the plating surface Wf-a, or it can be configured within a conduit that faces the plating surface Wf-a and is filled with plating solution. Additionally, when using a potential sensor as sensor 460, at least one reference potential sensor 462 can be provided within the plating tank 410. The reference potential sensor 462 can be configured outside the region between the substrate Wf and the anode 430. In other words, when viewed from a direction perpendicular to the plating surface Wf-a of the substrate Wf, the reference potential sensor 462 can be positioned in a location that does not overlap with the substrate Wf and the anode 430. Control module 800 can infer the formation rate of the coating formed on the plating surface Wf-a and determine the thickness of the coating based on the potential difference between sensor 460 (the potential sensor) and reference potential sensor 462. This is based on the correlation between the plating current and potential during the plating process. However, as the sensor 460, any sensor capable of detecting parameters related to the plating can be used, and other sensors such as white confocal optical distance sensors, magnetic field sensors, or eddy current sensors can be used instead of a potential sensor. In addition, this embodiment shows an example in which a sensor 460 for detecting parameters related to the plating is provided, but the sensor 460 may not be provided.

[0045] A shield 470 is provided in the cathode region 422 to shield the current flowing from the anode 430 to the substrate Wf. In this embodiment, the shield 470 is provided at the same height as the blade 480, but is not limited to the example described above. The shield 470 is, for example, a generally plate-shaped component made of a dielectric material. The shield 470 is configured to be movable to a shielding position between the plated surface Wf-a of the substrate Wf and the anode 430, and to a retracted position away from the plated surface Wf-a and the anode 430. In other words, the shield 470 is configured to be movable to a shielding position below the plated surface Wf-a, and to a retracted position away from the plated surface Wf-a. The position of the shield 470 is controlled by a drive mechanism 472 that receives instructions from the control module 800. The drive mechanism 472 can be implemented by a known mechanism such as a motor or a solenoid.

[0046] <Resistors>

[0047] The resistive element 450 of this embodiment will be described in detail. The resistive element 450 of this embodiment includes a first resistive component 452 and a second resistive component 456. The first resistive component 452 and the second resistive component 456 are components with a resistivity higher than that of the plating solution, and are preferably dielectrics. Furthermore, the first resistive component 452 and the second resistive component 456 may be formed of the same material or different materials.

[0048] Figure 4 This is a top view of the first resistive component in this embodiment. Additionally, in... Figure 4 In the diagram, shading lines are added to the area occupied by the outline of the second resistor 456 disposed on the back side of the paper of the first resistor 452. In one embodiment, the first resistor 452 is a circular plate-shaped component fixed to the plating tank 410 and slightly larger than the substrate Wf when viewed from above. Alternatively, as an example, the first resistor 452 may also be configured to be able to move up and down within the plating tank 410.

[0049] The first resistor component 452 has a plurality of first through holes 453 opening on the substrate holder 440 side and the anode 430 side. In one embodiment, the plurality of first through holes 453 are through holes of the same size, and are elongated openings with a circumferential length approximately twice the radial length. However, it is not limited to the above example; each of the plurality of first through holes 453 can be a perfect circle when viewed from above, can be any other shape, or can be through holes of different sizes. In addition, in one embodiment, the first through holes 453 are arranged on three or more virtual reference circles (with concentricity and different diameters) Figure 4 In this case, in one embodiment, the plurality of first through holes 453 disposed on adjacent reference circles are arranged at angularly offset positions relative to each other on the reference circles. In other words, for the first through holes 453 disposed on adjacent reference circles, the centers of the first through holes 453 are not arranged in a radially extending straight line, but are arranged circumferentially offset. However, the plurality of first through holes 453 are not limited to the above example, and may also be arranged in a radially extending straight line.

[0050] In another embodiment, a groove 454 for accommodating at least a portion of the sensor 460 is formed in the first resistive member 452. Figure 4 In this embodiment, the groove 454 is shown penetrating both the substrate holder 440 side and the anode 430 side; however, as an example, the anode 430 side may also be closed. Additionally, in one embodiment, the groove 454 extends from the outer periphery of the second resistor 456 to the inner side when viewed from above. In one embodiment, as... Figure 3 and Figure 4As shown, sensor 460 is disposed within groove 454 so that it does not protrude upwards from the upper surface of the second resistive member 456. As described above, resistive element 450 is preferably disposed near the plated surface Wf-a, and sensor 460, used to detect parameters related to the coating, is also preferably disposed near the plated surface Wf-a of substrate Wf. The sensor 460 is disposed within groove 454, thereby reducing the distance between resistive element 450 and the plated surface Wf-a of substrate Wf, enabling appropriate detection of parameters related to the coating thickness. Furthermore, in this embodiment, a paddle 480 is disposed between resistive element 450 and substrate Wf. The sensor 460 is disposed within groove 454, thereby preventing interference between sensor 460 and paddle 480 without restricting the movement of paddle 480 for stirring.

[0051] Figure 5 This is a top view of the second resistor component in this embodiment. In one embodiment, the second resistor component 456 is an annular plate-shaped component when viewed from above. In one embodiment, the inner diameter of the second resistor component 456 is 50% to 70%, preferably 55% to 65%, of the diameter of the first resistor component 452 or the substrate Wf. In another embodiment, the outer diameter of the second resistor component 456 is 70% to 90%, preferably 80% to 90%, of the diameter of the first resistor component 452 or the substrate Wf. However, the second resistor component 456 is not limited to an annular plate-shaped component and can be of any shape. The second resistor component 456 overlaps with the through-hole in such a way that the anode 430 cannot be visually identified through at least a portion of the through-holes 453 of the first resistor component 452 when viewed from the substrate Wf side (when viewed from above). In other words, at least a portion of the through-holes 453 of the first resistor component 452 are covered by the second resistor component 456. Additionally, in one embodiment, when viewed from above, the region formed overlapping with the outline of the second resistor 456 ( Figure 4 In the diagram, the first through-hole 453 (in the area marked with a shaded line) is completely covered by the second resistor element 456. However, it is also possible that, when viewed from above, a portion of the first through-hole 453 formed in the area overlapping with the shape of the second resistor element 456 is covered by the second resistor element 456, while a portion of the through-hole is not covered by the second resistor element 456.

[0052] In one embodiment, the second resistor 456 is disposed below the first resistor 452 (between the first resistor 452 and the anode 430). This is based on the fact that, as described above, the resistor 450 is preferably disposed near the substrate Wf, and the space above the resistor 450 is limited, while the space below the resistor 450 is relatively ample. However, the second resistor 456 may also be disposed above the first resistor 452 (between the first resistor 452 and the substrate holder 440). Additionally, the second resistor 456 may be supported within the plating tank 410 by a support mechanism (not shown). Furthermore, the second resistor 456 is concentrically disposed with the substrate Wf or the anode 430 when viewed from above. In one embodiment, the second resistor 456 has a smaller size than the substrate Wf or the anode 430 when viewed from above and is disposed closer to the center than the periphery of the substrate Wf or the anode 430 (see reference). Figure 3 Furthermore, in one embodiment, the thickness Th2 of the second resistor 456 is less than the thickness Th1 of the first resistor 452. As an example, the thickness Th2 of the second resistor 456 is preferably less than one-half, one-third, one-fifth, or one-tenth of the thickness Th1 of the first resistor 452.

[0053] The second resistor component 456 has a plurality of second through holes 457 opening on the substrate holder 440 side and the anode 430 side. In this embodiment, the plurality of second through holes 457 are formed at different positions when viewed from above than the plurality of first through holes 453 of the first resistor component 452. However, a portion of the plurality of second through holes 457 may also be formed at the same positions as the first through holes 453 of the first resistor component 452. In one embodiment, the plurality of second through holes 457 are arranged on two or more virtual reference circles that are concentric and have different diameters. Figure 5 (Referring to the dashed line). In other words, the plurality of second through holes 457 are arranged to be radially distributed in the second resistor member 456. Additionally, in one embodiment, each of the plurality of second through holes 457 is a through hole with the same shape as the first through hole 453 of the first resistor member 452 when viewed from above. However, the plurality of second through holes 457 can be of any shape. Furthermore, this embodiment shows an example of a plurality of second through holes 457 formed in the second resistor member 456, but it is also possible not to form second through holes 457.

[0054] The second resistor 456 is configured to move up and down so that its distance from the first resistor 452 is variable. In one embodiment, the second resistor 456 is configured to move to a position away from the first resistor 452 and to a position where it contacts the first resistor 452 and at least a portion of the plurality of first through holes 453 are blocked by the second resistor 456. However, the second resistor 456 may also not contact the first resistor 452. In another embodiment, the plating module 400 includes a drive mechanism 451 configured to move the second resistor 456 up and down. The drive mechanism 451 can be implemented, for example, by a known mechanism such as a pneumatic actuator. Alternatively, as an example, the drive mechanism 451 may also utilize power from a power source (e.g., a compressed air source) from the lifting mechanism 442 of the substrate holder 440.

[0055] Such a resistor 450 can change the electric field adjustment amount in the area where the second resistor 456 is mainly arranged by changing the distance between the first resistor 452 and the second resistor 456. Figure 6 This is a schematic longitudinal sectional view of the resistor 450 showing the first resistor component 452 and the second resistor component 456 separated. Figure 7 This is a longitudinal sectional view of the resistor 450 schematically showing the contact state between the first resistor component 452 and the second resistor component 456. Additionally, in Figure 6 and Figure 7 In the example shown, a portion of the current flowing near the resistor 450 is schematically illustrated by the dotted line. As described above, in this embodiment, when viewed from above, at least a portion of the plurality of first through-holes 453 of the first resistor 452 is covered by the second resistor 456. Figure 6 As shown, when the first resistor 452 and the second resistor 456 are fully separated, the current flowing through the plurality of first through holes 453 of the first resistor 452 is hardly blocked by the second resistor 456. However, if the distance between the first resistor 452 and the second resistor 456 becomes closer, the distance between the plurality of first through holes 453 of the first resistor 452 and the second resistor 456 becomes closer, and the current has difficulty flowing through the first through holes 453. Moreover, as Figure 7 As shown, if the first resistor 452 comes into contact with the second resistor 456, a portion of the first through-hole 453 of the first resistor 452 is blocked by the second resistor 456, and the current stops flowing. Thus, the electric field adjustment in the region where the second resistor 456 is mainly located varies depending on the distance between the first resistor 452 and the second resistor 456.

[0056] <Plating Treatment>

[0057] Next, the plating process in the plating module 400 of this embodiment will be described in more detail. The substrate Wf is immersed in the plating solution in the cathode region 422 using a lifting mechanism 442, thereby exposing the substrate Wf to the plating solution. The plating module 400 can perform plating processing on the plating surface Wf-a of the substrate Wf by applying a voltage between the anode 430 and the substrate Wf in this state. Alternatively, in one embodiment, the plating process is performed while rotating the substrate holder 440 using a rotation mechanism 448. Through the plating process, a conductive film (plating film) is deposited on the plating surface Wf-a of the substrate Wf.

[0058] The control module (controller) 800 of this embodiment can adjust the resistor 450 (the distance between the first resistor 452 and the second resistor 456) by controlling the drive mechanism 451, thereby improving the uniformity of the overall coating thickness distribution of the substrate Wf. As an example, the adjustment of the resistor 450 using the drive mechanism 451 is performed before the coating process begins. Alternatively, as an example, the adjustment of the resistor 450 using the drive mechanism 451 is performed in real time during the coating process based on the value detected by the sensor 460.

[0059] Figure 8 This is a flowchart illustrating an example of a method for setting the operation scheme of the resistor 450, the anode cover 426, and the shield 470 based on the control module 800. As an example, Figure 8 The method shown is performed when processing a new batch of substrates. Alternatively, the control module 800 can set only a portion of the operation schemes for the resistor 450, anode cover 426, and shield 470. Here, the operation scheme for the resistor 450 refers to the vertical position of the second resistor 456, that is, the distance between the first resistor 452 and the second resistor 456. The operation scheme for the anode cover 426 refers to the opening size of the anode cover 426. The operation scheme for the shield 470 refers to its forward and backward position. Alternatively, instead of setting the operation scheme through the control module 800 of the plating apparatus 1000, the operation scheme can be set by a computer external to the plating apparatus 1000 and sent to the plating apparatus 1000.

[0060] exist Figure 8In the example shown, firstly, the control module 800 acquires the resist pattern of the substrate Wf, which is the object of processing (step S110). The resist pattern refers to the pattern formed on the resist layer on the plating surface Wf-a, so as to form the desired plating pattern through the plating process. The resist pattern can also be acquired by detecting the substrate Wf using a sensor provided in the plating apparatus 1000. As an example, the plating apparatus 1000 may also be equipped with an imaging sensor (not shown) such as a camera that takes pictures of the plating surface Wf-a of the substrate Wf. Moreover, the control module 800 can also acquire the imaging data detected by the imaging sensor and acquire the resist pattern of the plating surface Wf-a by analyzing the imaging data. The acquisition of the resist pattern based on the imaging data can be performed using known methods based on shadows or feature points in the imaging data. In addition, as an example, the control module 800 can also acquire the resist pattern via external input through wired or wireless communication.

[0061] Then, the control module 800 sets the operation schemes for the resistor 450, anode cover 426, and shield 470 based on the acquired resist pattern (step S120). As a specific example, the control module 800 calculates the plating growth coefficient for each defined area of ​​the plated surface Wf-a of the substrate Wf based on the acquired resist pattern, and sets the operation scheme for each controlled object based on the calculated plating growth coefficient. Here, the plating growth coefficient is a parameter representing the growth rate (formation rate) of the film in the least shielded current state of each of the resistor 450, anode cover 426, and shield 470. As an example, the plating growth coefficient can be the amount of film formed per unit time (e.g., 1 second) (e.g., nanometers). As a specific example, the control module 800 can calculate the aperture ratio of the resist layer in each defined area based on the resist pattern, and calculate the plating growth coefficient based on the calculated aperture ratio. This is based on the fact that the deposition area in the region with a large aperture ratio of the resist layer is large and the amount of coating required to form a certain amount of film is large, and the growth rate of the film tends to be smaller compared with the region with a small aperture ratio of the resist layer.

[0062] Figure 9 This is a schematic diagram illustrating the resist pattern formed on the plated surface Wf-a of a substrate Wf in one embodiment. Figure 9In this embodiment, resist openings are formed only in the cross-shaped region A1, which is shaded, and the region A2 outside the cross-shaped region A1 becomes a non-opening region without resist openings. When plating is performed on the substrate Wf with such a resist pattern, no plating current flows through the non-opening region A2, and only the opening region A1 flows. In addition, in this embodiment, the plating process is performed while rotating the substrate holder 440 using the rotation mechanism 448. In region A1, especially in the cross-shaped protrusion region that includes region A2 in the circumferential direction, the plating current is concentrated and the film thickness is increased. In this specification, the region in which resist openings are formed almost entirely when viewed along the circumferential direction is called the "central region B1" (in Figure 11 In the example shown, the inner circular area is enclosed by the dotted line C1. Furthermore, when viewed circumferentially, the area containing both the region with resist openings (opening region A1) and the region without resist openings (non-opening region A2), where the area of ​​opening region A1 is larger than the area of ​​non-opening region A2 circumferentially, is called the "intermediate region B2" (in...). Figure 11 In the example shown, the annular region is enclosed by the dotted lines C1 and C2. Furthermore, when viewed circumferentially, the region containing both the open region A1 and the non-open region A2, where the area of ​​the open region A1 is smaller than the area of ​​the non-open region A2 circumferentially, is called the "outer peripheral region B3" (in...). Figure 11 In the example shown, the area is a ring shape surrounded by dotted lines C2 and C3. Additionally, in Figure 11 In the example shown, from the center of the plated surface Wf-a outwards, the regions are, in sequence, central region B1, intermediate region B2, and outer peripheral region B3. No resist openings are formed on the outer peripheral side of the outer peripheral region B3. However, this is not limited to the above example; any resist pattern can be formed on the substrate Wf.

[0063] Here, the anode cover 426 or shield 470 of the plating module 400 can appropriately adjust the formation rate of the coating near the outer periphery of the surface to be plated, Wf-a. However, in the case of... Figure 9 When the substrate Wf shown is subjected to plating treatment, the plating formation rate of the inner peripheral area (especially the middle area B2) is relatively higher than that of the outer periphery, which may impair the uniformity of the coating thickness.

[0064] In this embodiment, the plating module 400 is configured such that the resistive body 450 includes a second resistive member 456 in the shape of an annular plate, allowing adjustment of the electric field adjustment of the resistive body 450 in the region where the second resistive member 456 is mainly disposed. Therefore, the plating formation speed of the intermediate region B2 can be adjusted by adjusting the current flowing through the intermediate region B2. As an example, in... Figure 9In the substrate Wf, when the deposition rate of the intermediate region B2 surrounded by dotted lines C1 and C2 is relatively high, the deposition thickness formed in the intermediate region B2 can be reduced by bringing the second resistor 456 closer to the first resistor 452. Thus, as an example, even when... Figure 9 When the substrate Wf shown is subjected to plating treatment, the uniformity of the plating thickness can also be improved. Furthermore, the plating module 400 of this embodiment includes an anode cover 426 and a shield 470. Therefore, for the intermediate region B2, the plating speed can be adjusted by rotating the first resistor 452, and for the outer peripheral region B3, the plating speed can be adjusted by the anode cover 426 and the shield 470. Thus, by controlling the resistor 450, the anode cover 426, and the shield 470, the plating speed can be adjusted in each region of the substrate Wf, and the uniformity of the plating thickness can be improved. Additionally, the size of the second resistor 456 of the resistor 450 can be determined based on the intermediate region B2, for example, by setting it to approximately the same size as the intermediate region B2.

[0065] Figure 10 This is a flowchart illustrating an example of a method for setting the operation scheme of the resistor 450, anode cover 426, and shield 470 during the plating process based on the control module 800. The plating process is executed... Figure 10 The method shown is used instead of Figure 8 The method or modification shown is by Figure 8 The method shown defines the action plan. Alternatively, the control module 800 can also define the action plan for only a portion of the resistor 450, anode cover 426, and shield 470.

[0066] If the plating process begins (step S210), the control module 800 acquires plating-related parameters in real time from the sensor 460 (step S220). In this embodiment, as the substrate Wf rotates, the plating-related parameters are detected by the sensor 460. In one embodiment, the plating-related parameters are detected at multiple locations along the radial direction on the plating surface Wf-a. The control module 800 calculates the film thickness distribution on the plating surface Wf-a based on the values ​​detected by the sensor 460 (step S230). Next, the control module 800 sets the operation schemes for the resistor 450, the anode cover 426, and the shield 470 based on the calculated film thickness distribution (step S240). The control module 800 repeats the process of steps S220 to S240 to set the operation schemes for the controlled objects until the plating process is completed (step S250). Then, the control module 800 controls the resistor 450, the anode cover 426, and the shield 470 based on the set operation schemes. In this way, based on the coating-related parameters obtained from the sensor 460, the action scheme of the resistor 450 and the like can be set or modified during the coating process, thereby improving the uniformity of the coating thickness.

[0067] <First Variation>

[0068] Figure 11 This is a longitudinal sectional view of resistor 450A schematically showing the state in which the first resistor component 452A and the second resistor component 456 are separated in the first modified example. Figure 12 This is a longitudinal sectional view of a resistor 450A schematically showing the contact state between the first resistor member 452A and the second resistor member 456 in the first modified example. Regarding the resistor 450A of the first modified example, descriptions repeating those of the resistor 450 in the above-described embodiment are omitted. In the resistor 450A of the first modified example, a groove 455, which appears annular when viewed from below, is formed on the lower surface of the first resistor member 452A, allowing the second resistor member 456 to be accommodated. In one embodiment, as... Figure 12 As shown, when the second resistor 456 contacts the first resistor 452 and is disposed in the groove 455, the lower surface 452-a of the first resistor 452 and the lower surface 456-a of the second resistor 456 are disposed on the same plane. However, it is not limited to the above example; the groove 455 of the first resistor 452 may be formed to be shallower or deeper than the thickness Th2 of the second resistor 456. Thus, in the first modified example, the first resistor 452A has a groove 455 capable of accommodating at least a portion of the second resistor 456. As a result, the thickness Th2 of the second resistor 456 can be increased within the limited space within the plating tank 410, or the range of vertical movement of the second resistor 456 can be increased.

[0069] <Second Variation>

[0070] Figures 13-15 This is a schematic longitudinal sectional view of the resistor 450B in the second variation, showing the resistor 452 and the second resistor 456B separated by a first to a third distance. Regarding the resistor 450B of the second variation, descriptions that overlap with those of the resistor 450 in the above-described embodiment are omitted. The second resistor 456B in the resistor 450B of the variation has a plurality of protrusions 458, which, when viewed from above, are formed at the locations of the plurality of first through holes 453 formed on the first resistor 452 and can be inserted into the first through holes 453. In one example, the plurality of protrusions 458 includes: a first protrusion 458a having a first height h1, a second protrusion 458b having a second height h2 lower than the first height h1, and a third protrusion 458c having a third height h3 lower than the second height h2. However, the plurality of protrusions 458 may include two or more protrusions with different heights from each other, or they may all be of the same height.

[0071] In the second variation, the drive mechanism 451 for moving the second resistor 456B up and down includes a cam 451B disposed within the plating tank 410 and a drive source (not shown) configured to rotate the cam 451B. Here, a known mechanism such as a motor can be used as the drive source. In the second variation, the rotation of the cam 451B within the plating tank 410 allows the second resistor 456B to move up and down to adjust the distance between the first resistor 452 and the second resistor 456B.

[0072] In this second variation, the resistor 450B, similarly to the embodiment described above, allows for alteration of the electric field adjustment in the area where the second resistor 456B is primarily located by changing the distance between the first resistor 452 and the second resistor 456B. For example... Figure 13 As shown, when the first resistor 452 and the second resistor 456B are fully separated, the current flowing through the plurality of first through holes 453 of the first resistor 452 is hardly blocked by the second resistor 456. However, if the distance between the first resistor 452 and the second resistor 456 becomes closer, the distance between the plurality of first through holes 453 of the first resistor 452 and the plurality of protrusions 458 formed in the second resistor 456B becomes closer, and the current does not easily flow through the first through holes 453. Furthermore, in the second variation, the plurality of protrusions 458 have different heights h1 to h3, such as... Figure 14As shown, if the first resistor 452 and the second resistor 456 are brought close together, the first protrusion 458a, which has a higher height, is inserted into the first through hole 453 first. Therefore, current does not flow or is difficult to flow through the first through hole 453 where the first protrusion 458a is inserted. Furthermore, if the first resistor 452 and the second resistor 456 are brought even closer, then... Figure 15 As shown, the second protrusion 458b is inserted into the first through hole 453. Therefore, current does not flow or is difficult to flow through the first through hole 453 where the first protrusion 458a is inserted and the first through hole 453 where the second protrusion 458b is inserted. Thus, the resistor 450B of the second modification can insert the first to third protrusions 458a to 458c into the first through hole 453 according to the distance between the first resistor member 452 and the second resistor member 456, preventing current from flowing through the first through hole 453. Therefore, the resistor 450B of the second modification can more precisely change the electric field adjustment amount in the area where the second resistor member 456 is mainly located.

[0073] <Other variations>

[0074] In the above-described embodiment, the plating module 400 is configured such that the plating surface Wf-a of the substrate Wf faces downwards during the plating process. However, it is not limited to the above example; as an example, it may also be configured such that the plating surface Wf-a of the substrate Wf is opposite to the anode 430 in the horizontal direction.

[0075] The present invention can also be described in the following forms.

[0076] [Form 1] According to Form 1, a plating apparatus is provided, comprising: a plating tank; a substrate holder configured to hold a substrate; an anode disposed in the plating tank opposite to the substrate held by the substrate holder; and a resistor disposed between the substrate holder and the anode for adjusting an electric field. The resistor comprises: a first resistor member and a second resistor member disposed between the first resistor member and the substrate holder or between the first resistor member and the anode. The first resistor member has a plurality of first through holes opening on the substrate holder side and the anode side. At least a portion of the plurality of first through holes overlaps with the second resistor member in such a way that the anode cannot be visually identified when viewed from the substrate side. The second resistor member is configured to be at a variable distance from the first resistor member.

[0077] According to aspect 1, a coating apparatus can be proposed that can improve the uniformity of the thickness of the coating formed on the object to be coated.

[0078] [Modifier 2] According to Modifier 2, based on Modifier 1, when viewed from the substrate holder side, the second resistor is annular. According to Modifier 2, the thickness of the coating can be adjusted, particularly in the annular region.

[0079] [Modifier 3] According to Modifier 3, based on Modifier 1 or 2, a plurality of second through holes are formed in the second resistor component, which open on the substrate holder side and the anode side.

[0080] [Form 4] According to Form 4, based on Form 3, the above-mentioned plurality of second through holes include: a plurality of through holes formed on the first reference circle, and a plurality of through holes formed on a second reference circle that is concentric with the first reference circle but has a different diameter.

[0081] [Modifier 5] According to Modifier 5, based on Modifiers 1 to 4, the second resistor is configured to be movable to a position away from the first resistor and to a position in contact with the first resistor where at least a portion of the plurality of first through holes is blocked by the second resistor. According to Modifier 5, by bringing the first resistor into contact with the second resistor, at least a portion of the plurality of first through holes of the first resistor can be blocked.

[0082] [Modifier 6] According to Modifier 6, based on Modifiers 1 to 5, a groove capable of accommodating at least a portion of the second resistive member is formed in the first resistive member. According to Modifier 6, the thickness of the second resistive member can be increased, or the movable range of the second resistive member can be expanded.

[0083] [Modifier 7] According to Modifier 7, based on Modifiers 1 to 6, the second resistor member has a plurality of protrusions. When viewed from the substrate holder side, the plurality of protrusions are formed at the positions where the plurality of first through holes are formed in the first resistor member and can be inserted into the plurality of first through holes. The plurality of protrusions includes: a first protrusion having a first height and a second protrusion having a second height lower than the first height. According to Modifier 7, the resistor can be adjusted to a state where a first protrusion is inserted in a portion of the plurality of first through holes, and a state where a first protrusion is inserted in a portion of the plurality of first through holes and a second protrusion is inserted in other portions of the plurality of first through holes.

[0084] [Modifier 8] According to Modifier 8, based on Modifiers 1 to 7, the plating apparatus includes a drive mechanism configured to move the second resistive member to adjust the distance between the first resistive member and the second resistive member. According to Modifier 8, the distance between the first resistive member and the second resistive member can be adjusted by the drive mechanism.

[0085] [Modifier 9] According to Modifier 9, based on Modifier 8, the drive mechanism has a pneumatic actuator disposed outside the plating tank.

[0086] [Modifier 10] According to Modifier 10, based on Modifier 8, the drive mechanism has: a cam disposed in the plating groove, and a drive source configured to rotate the cam.

[0087] [Version 11] According to Version 11, based on Versions 8 to 10, the plating apparatus includes a controller that controls the drive mechanism based on the resist pattern of the substrate held by the substrate holder. According to Version 11, the distance between the first resistive member and the second resistive member can be controlled by the controller.

[0088] [Modifier 12] According to Modifier 12, based on Modifier 11, the plating apparatus includes an anode cover disposed between the anode and the resistive element, and configured to have an anode opening penetrating between the anode side and the substrate holder side. The size of the anode opening can be adjusted, and the controller controls the drive mechanism and the anode cover based on the resist pattern. According to Modifier 12, the distance between the first resistive element and the second resistive element, as well as the size of the anode opening, can be controlled by the controller.

[0089] [Form 13] According to Form 13, based on Forms 1 to 12, the substrate holding structure is configured to hold the substrate in the plating tank with the plating surface facing downwards, and the second resistor is disposed between the first resistor and the anode.

[0090] The embodiments of the present invention have been described above. However, the above embodiments are for the purpose of easy understanding of the present invention and are not intended to limit the present invention. The present invention can be modified and improved without departing from its spirit, and equivalent structures are naturally included in the present invention. Furthermore, within the scope of solving at least a portion of the above-mentioned problems or achieving at least a portion of the effects, any combination of embodiments and modifications is possible, and any combination or omission of the constituent elements described in the claims and specification is possible.

[0091] Explanation of reference numerals in the attached figures

[0092] Wf-a…plated surface; Wf…substrate; 400…plating module; 410…plating tank; 420…diaphragm; 422…cathode region; 424…anode region; 430…anode; 440…substrate holder; 442…lifting mechanism; 448…rotating mechanism; 450, 450A, 450B…resistors; 451…drive mechanism; 451B…cam; 452, 452A…first resistor; 453…first through hole; 455…groove; 456, 456B…second resistor; 457…second through hole; 458, 458a~458c…protrusion; 460…sensor; 470…shield; 480…paddle; 482…paddle stirring mechanism; 800…control module; 1000…plating device.

Claims

1. A plating apparatus wherein, Possessing: a plating bath; a substrate holder configured to hold a substrate; an anode disposed in the plating bath in opposition to the substrate held by the substrate holder; and a resistor disposed between the substrate holder and the anode for adjusting an electric field, the resistor possesses: a first resistor member, and a second resistor member disposed between the first resistor member and the substrate holder or between the first resistor member and the anode, a plurality of first through-holes are formed in the first resistor member that open on the substrate holder side and the anode side, the second resistor member has an outer shape that is smaller than that of the first resistor member when viewed from the substrate side to the anode side, and at least a portion of the plurality of first through-holes overlaps the second resistor member in a manner that the anode cannot be visually recognized when viewed from the substrate side to the anode side, the second resistor member is configured to be variable in distance from the first resistor member.

2. The plating apparatus according to claim 1, wherein the second resistor member is circular ring-shaped when viewed from the substrate holder side to the anode side.

3. The plating apparatus according to claim 1, wherein a plurality of second through-holes are formed in the second resistor member that open on the substrate holder side and the anode side.

4. The plating apparatus according to claim 3, wherein the plurality of second through-holes include: a plurality of through-holes formed on a first reference circle, and a plurality of through-holes formed on a second reference circle concentric with the first reference circle and different in diameter.

5. The plating apparatus according to claim 1, wherein the second resistor member is configured to be movable to a position apart from the first resistor member, and a position in contact with the first resistor member and at least a portion of the plurality of first through-holes is plugged by the second resistor member.

6. The plating apparatus according to claim 1, wherein a groove capable of accommodating at least a portion of the second resistor member is formed in the first resistor member.

7. The plating apparatus according to claim 1, wherein the second resistor member has a plurality of protrusions that are formed at positions of the first resistor member where the plurality of first through-holes are formed and are capable of being inserted into the plurality of first through-holes when viewed from the substrate holder side to the anode side, the plurality of protrusions include: a first protrusion having a first height, and a second protrusion having a second height lower than the first height.

8. The plating apparatus according to claim 1, wherein the plating apparatus possesses a driving mechanism configured to move the second resistor member to adjust the distance of each other of the first resistor member and the second resistor member.

9. The plating apparatus according to claim 8, wherein the driving mechanism has a pneumatic actuator disposed outside the plating bath.

10. The plating apparatus according to claim 8, wherein the driving mechanism has: a cam disposed inside the plating bath, and a driving source configured to rotate the cam.

11. The plating apparatus according to claim 8, wherein The plating apparatus includes a controller that calculates a plating growth coefficient for each prescribed region of a plating surface of a substrate based on a resist pattern of the substrate held by a substrate holder, and sets an operation scheme based on the calculated plating growth coefficient to control the drive mechanism.

12. The plating apparatus according to claim 11, wherein The plating apparatus includes an anode cover disposed between the anode and the resistor, and configured to have an anode opening through the anode side and the substrate holder side, and to adjust the size of the anode opening, The controller sets an operation scheme based on the calculated plating growth coefficient to control the drive mechanism and the anode cover.

13. The plating apparatus according to any one of claims 1 to 12, wherein The substrate holder is configured to hold the substrate in a state in which the plating surface faces downward in the plating bath, The second resistor member is disposed between the first resistor member and the anode.

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