Plating device and plating method

Abstract

The present invention improves the in-plane uniformity of a film plated on a polygonal substrate. The plating device comprises: a plating tank; a substrate holder configured to hold a polygonal substrate; an anode arranged in the plating tank so as to be opposite to the substrate held by the substrate holder; and an anode mask defining an opening corresponding to the outer shape of the polygonal substrate. The anode mask comprises: a first mask component defining a first convex portion protruding toward the center of the opening in a central portion of a first opening side corresponding to the first side of the polygonal substrate in the opening; and a second mask component defining a second convex portion protruding toward the center of the opening in a central portion of a second opening side corresponding to the second side of the polygonal substrate in the opening, wherein the anode mask is configured to be able to adjust the mutual distance between the first mask component and the second mask component.

Description

Technical Field

[0001] The invention relates to a plating device and a plating method. Background Art

[0002] In the past, wiring was formed in tiny wiring grooves, holes or resist openings provided on the surface of substrates such as semiconductor wafers, or bumps (protruding electrodes) electrically connected to electrodes of a package were formed on the surface of the substrate. Methods for forming the wiring and bumps include, for example, known electrolytic plating, vapor deposition, printing, and ball bumping. As the number of I / Os of semiconductor chips increases and the pitch becomes narrower, electrolytic plating methods that can be miniaturized and have relatively stable performance are often used.

[0003] When forming wiring or bumps by electrolytic plating, a seed layer (power supply layer) with low resistance is formed on the surface of the barrier metal provided in the wiring groove, hole or resist opening on the substrate. A plated film grows on the surface of the seed layer.

[0004] Generally speaking, the substrate to be plated has electrical contacts at its periphery. That is, the current flows from the center of the substrate to be plated toward the periphery. As the distance moves away from the center of the substrate, the potential gradually decreases corresponding to the resistance of the seed layer, thereby generating a lower potential at the periphery of the substrate closer to the center of the substrate than at the center of the substrate. The phenomenon that the reduction current of metal ions, i.e., the plating current, is concentrated toward the periphery of the substrate due to the potential difference between the center and the periphery of the substrate is called the terminal effect.

[0005] In addition, as the shape of a substrate to be plated by the electrolytic plating method, a circular substrate or a quadrilateral substrate is known (for example, refer to Patent Documents 1 and 2).

[0006] In a circular substrate, the distance from the center of the circular substrate to the peripheral portion of the substrate and the distance between adjacent electrical contacts are the same throughout the entire circumference of the substrate. Therefore, the terminal effect when the circular substrate is plated is produced almost identically throughout the entire circumference of the substrate. Therefore, when the circular substrate is plated, the plating speed in the central portion of the substrate is reduced, and the film thickness of the plated film in the central portion of the substrate is thinner than the plated film in the peripheral portion of the substrate. In the past, in order to suppress the reduction of the in-plane uniformity of the film thickness caused by the terminal effect, current was supplied to the electrical contacts uniformly arranged at the peripheral portion of the circular substrate, and an adjustment plate such as disclosed in Patent Document 3 was used to adjust the electric field applied to the circular substrate, i.e., the migration of electroactive ions.

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 09-125294

[0008] Patent Document 2: Japanese Patent Publication No. 03-029876

[0009] Patent Document 3: Japanese Patent Application Publication No. 2005-029863

[0010] However, in a polygonal substrate, when electrical contacts are arranged at the periphery of all sides of the polygon, when an adjustment plate or an anode mask having an opening of a shape similar to that of the substrate is used in the same manner as in the case of a circular substrate, the symmetry of the substrate itself is low, so the distribution of the plated film thickness tends to be different near the corner and in the center of the side (the center between vertices). Therefore, the film thickness distribution is prone to produce peculiar points, and in a polygonal substrate, there is a tendency for the final plated film thickness to become smaller in the area close to the corner that is relatively long from the center.

[0011] In addition, this influence varies in accordance with the resist opening rate of the polygonal substrate to be processed, the recipe of the plating process, and the utilization state of the plating solution. Therefore, it is also considered that the opening size of the anode mask can be changed in accordance with the state of the plating process. However, for example, in the case where the terminal effect is small and large, the film thickness tends to be greatly different in the corners and other areas, and there is a situation where the in-plane uniformity of the plated film cannot be fully improved by simply adjusting the opening size. Summary of the invention

[0012] The present invention has been made in view of the above-mentioned problems, and one of its objects is to improve the in-plane uniformity of a film plated on a polygonal substrate.

[0013] According to one embodiment, a plating device is proposed, which comprises: a plating tank; a substrate holder configured to hold a polygonal substrate; an anode arranged in the above-mentioned plating tank so as to be opposite to the substrate held by the above-mentioned substrate holder; and an anode mask defining an opening corresponding to the outer shape of the above-mentioned polygonal substrate, wherein the anode mask comprises: a first mask part defining a first convex part protruding toward the center of the opening at a central portion of a first opening edge in the above-mentioned opening corresponding to the first side of the above-mentioned polygonal substrate; and a second mask part defining a second convex part protruding toward the center of the opening at a central portion of a second opening edge in the above-mentioned opening corresponding to the second side of the above-mentioned polygonal substrate, wherein the above-mentioned anode mask is configured to be able to adjust the mutual distance between the above-mentioned first mask part and the above-mentioned second mask part.

[0014] According to another embodiment, a plating method is proposed, which is a method for plating the polygonal substrate by allowing current to flow between an anode and a polygonal substrate in a plating device, and the plating method includes the following steps: in an anode mask defining an opening corresponding to the outer shape of the polygonal substrate, adjusting the mutual distance between a first mask component and a second mask component possessed by the anode mask, wherein the first mask component defines a first convex portion protruding toward the center of the opening at a central portion of a first opening edge in the opening corresponding to the first edge of the polygonal substrate, and the second mask component defines a second convex portion protruding toward the center of the opening at a central portion of a second opening edge in the opening corresponding to the second edge of the polygonal substrate; and allowing current to flow between the anode and the polygonal substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an overall configuration diagram of a plating apparatus according to an embodiment.

[0016] Figure 2 It is a schematic side sectional view (longitudinal sectional view) of a plating unit provided in the plating apparatus.

[0017] Figure 3A This is a diagram showing an anode mask in one embodiment from the substrate side.

[0018] Figure 3B This is a diagram showing an anode mask in one embodiment from the substrate side.

[0019] Figure 3C This is a diagram showing an anode mask in one embodiment from the substrate side.

[0020] Figure 4A This is a diagram showing an adjustment plate in one embodiment from the substrate side.

[0021] Figure 4B This is a diagram showing an adjustment plate and an anode mask in one embodiment from the substrate side.

[0022] Figure 5A This is a schematic diagram showing the plating film thickness when a quadrilateral substrate is plated by the plating apparatus of this embodiment under the condition that the terminal effect is large.

[0023] Figure 5B This is a schematic diagram showing the plated film thickness when a quadrilateral substrate is plated by the plating apparatus of this embodiment under the condition that the terminal effect is moderate.

[0024] Figure 5C This is a schematic diagram showing the plating film thickness when a quadrilateral substrate is plated by the plating apparatus of this embodiment under the condition that the terminal effect is small.

[0025] Fig. 6A This is a schematic diagram showing the plating film thickness when a quadrilateral substrate is plated by a plating apparatus of a comparative example under the condition that the terminal effect is large.

[0026] Figure 6B This is a schematic diagram showing the plated film thickness when a quadrilateral substrate is plated by a plating apparatus of a comparative example under the condition that the terminal effect is moderate.

[0027] Figure 6C This is a schematic diagram showing the plating film thickness when a quadrilateral substrate is plated by a plating apparatus of a comparative example under the condition that the terminal effect is small.

[0028] Figure 7 This is a simplified front view of the substrate holder used in the plating unit.

[0029] Figure 8 is a simplified side view of the substrate holder.

[0030] Fig. 9 It is the rear view of the front panel body.

[0031] Fig.10 It is a rear view showing an enlarged view of the vicinity of the corner of the face portion on the side close to the connector.

[0032] Fig.11A This is a diagram showing an anode mask in a modified example from the substrate side.

[0033] Fig. 11B This is a diagram showing an anode mask in a modified example from the substrate side.

[0034] Fig. 11C This is a diagram showing an anode mask in a modified example from the substrate side. DETAILED DESCRIPTION

[0035] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings described below, the same or corresponding components are denoted by the same reference numerals and repeated descriptions are omitted.

[0036] Figure 1 The overall configuration diagram of the plating device according to the embodiment is shown. Figure 1As shown in FIG. 1 , the plating device comprises: two cassette work tables 102, on which cassettes 100 containing substrates such as semiconductor wafers are mounted; an aligner 104, which aligns the position of the substrate in a predetermined direction; and a rinse dryer 106, which dries the substrate after the plating process. A substrate loading and unloading unit 120 is provided near the rinse dryer 106, on which a substrate holder 30 is mounted and substrates are loaded and unloaded. A substrate transport device 122 composed of a transport robot for transporting substrates between the units is arranged in the center of the units 100, 104, 106, and 120.

[0037] The substrate loading and unloading section 120, a storage container 124 for storing and temporarily placing the substrate holder 30, a pre-wetting tank 126 for immersing the substrate in pure water, a pre-preg tank 128 for etching away the oxide film on the surface of the conductive layer such as the seed layer formed on the surface of the substrate, a first cleaning tank 130a for cleaning the pre-preg substrate and the substrate holder 30 together with a cleaning liquid (pure water, etc.), an air blowing tank 132 for removing liquid from the cleaned substrate, a second cleaning tank 130b for cleaning the plated substrate and the substrate holder 30 together with a cleaning liquid, and the plating unit 10 are arranged in this order.

[0038] The plating unit 10 is configured by accommodating a plurality of plating tanks 14 in an overflow tank 136. Each plating tank 14 accommodates one substrate therein, and performs copper plating or the like on the surface of the substrate by immersing the substrate in a plating solution held therein.

[0039] The plating device has a substrate holder conveying device 140, which is located on the side of each of these machines and conveys the substrate holder 30 together with the substrate between these machines, for example, using a linear motor method. The substrate holder conveying device 140 has: a first conveyor 142, which conveys the substrate between the substrate loading and unloading part 120, the storage tank 124, the pre-wetting tank 126, the pre-preg tank 128, the first cleaning tank 130a and the blowing tank 132; and a second conveyor 144, which conveys the substrate between the first cleaning tank 130a, the second cleaning tank 130b, the blowing tank 132 and the plating unit 10. The plating device may not have the second conveyor 144, but only have the first conveyor 142.

[0040] A paddle driving device 146 is disposed on the opposite side of the substrate holder transport device 140 across the overflow tank 136. The paddle driving device 146 drives the paddle 16 (see Figure 2 ), the paddle 16 is located inside each plating tank 14 and serves as a stirring rod for stirring the plating liquid in the plating tank 14.

[0041] The substrate loading and unloading section 120 includes a flat plate-shaped loading plate 152 that freely slides laterally along the guide rail 150. Two substrate holders 30 are placed side by side on the loading plate 152 in a horizontal state. After the substrate is transferred between one substrate holder 30 and the substrate conveying device 122, the loading plate 152 slides laterally, and the substrate is transferred between the other substrate holder 30 and the substrate conveying device 122.

[0042] In addition, the plating apparatus includes a control device 17 for controlling the entire apparatus. The control device 17 can be constituted by, for example, a general computer or a dedicated computer having an input / output interface with an operator.

[0043] Figure 2 yes Figure 1 FIG. 1 is a schematic side cross-sectional view of a plating unit 10 provided in the plating apparatus shown in FIG. Figure 2 As shown, the plating unit 10 has: a plating tank 14, which is configured to accommodate a plating solution, a substrate holder 30 and an anode holder 13; and an overflow tank (not shown). The substrate holder 30 is configured to hold a polygonal substrate Wf, and the anode holder 13 is configured to hold an anode 12 having a metal surface. The polygonal substrate Wf and the anode 12 are electrically connected via a plating power supply 15, so that current flows between the substrate Wf and the anode 12, thereby forming a plated film on the surface of the substrate Wf.

[0044] The anode holder 13 has an anode shield 18 for adjusting the electric field between the anode 12 and the substrate Wf. The anode shield 18 is a substantially plate-shaped member made of, for example, a dielectric material, and is disposed in front of the anode holder 13. Here, the front of the anode holder 13 refers to the surface on the side opposite to the substrate holder 30. That is, the anode shield 18 is disposed between the anode 12 and the substrate holder 30. The anode shield 18 has an opening 18a in the substantially central portion for the current flowing between the anode 12 and the substrate Wf to pass through.

[0045] Figure 3A to Figure 3C This is a diagram showing an anode mask 18 of one embodiment from the substrate Wf side. The anode mask 18 includes: a frame member 182 defining a polygonal opening corresponding to the polygonal shape of the substrate Wf; and a plurality of mask members 184 to 187, which are arranged adjacent to the frame member 182 and can move relative to the frame member 182. Figure 3A to Figure 3CIn the example shown, the substrate Wf has a substantially square plate shape, and the frame member 182 defines a substantially square opening 182a. In addition, four mask members 184 to 187 are provided corresponding to each side of the opening 182a. For ease of observation, the frame member 182 and the four mask members 184 to 187 are shaded. In this embodiment, the four mask members 184 to 187 are of the same shape and are arranged in a state where each is rotated 90 degrees. However, the four mask members 184 to 187 may also be of different shapes. As a representative example, in Figure 3A to Figure 3C In FIG. 1 , the mask member 184 provided corresponding to the upper side of the opening 182 a is given a hatching different from that of the other mask members 185 to 187 .

[0046] The plurality of mask members 184 to 187 respectively include: side portions 184a to 187a, which are along the sides of the substrate Wf (along the opening sides of the frame member 182); and protrusions 184b to 187b, which are provided at positions corresponding to the centers of the sides of the substrate Wf and protrude toward the center (inner peripheral side) of the anode mask 18. As an example, the protrusions 184b to 187b are trapezoidal in shape that narrows toward the center of the opening 18a of the anode mask 18. The plurality of mask members 184 to 187 are configured to be movable relative to the frame member 182, and define the opening 18a of the anode mask 18 together with the frame member 182. Figure 3A In the example shown, the plurality of mask members 184 to 187 are located outside and do not overlap with the opening 182a of the frame member 182, and the opening 182a of the frame member 182 becomes the opening 18a of the anode mask 18. From this state, if the plurality of mask members 184 to 187 are moved toward the center relative to the frame member 182, as shown in FIG. Figure 3B As shown in FIG. 1 , the protrusions 184b to 187b protrude into the opening 182a of the frame member 18, respectively. Figure 3B In the example shown, the opening defined by a part of the frame member 182 and a part of the convex portions 184b to 187b of the mask members 184 to 187 becomes the opening of the anode mask 18. Then, if the plurality of mask members 184 to 187 are further moved toward the center relative to the frame member 182, as shown in FIG. Figure 3C As shown in FIG. 1 , the convex portions 184b to 187b and the side portions 184a to 187a of the mask members 184 to 187 protrude into the opening 182a of the frame member 182. Figure 3C In the example shown, the opening defined by the plurality of mask members 184 to 187 serves as the opening 18a of the anode mask 18. Figure 3A , Figure 3B , Figure 3C Each of the figures shows an example of the state of the opening 18a of the anode mask 18. The positions of the plurality of mask members 184 to 187 may also be changed smoothly.

[0047] The anode shield 18 is formed of, for example, vinyl chloride as a dielectric. The frame member 182 and the plurality of shield members 184 to 187 may also be formed of the same material. The plurality of shield members 184 to 187 are preferably arranged adjacent to the frame member 182. The shield members 184 to 187 may also be arranged on the side of the frame member 182 opposite to the anode 12, or may be arranged on one side of the anode 12. The shield members 184 to 187 are configured to be movable relative to the frame member 182. The shield members 184 to 187 may also be configured to be equidistant from the center of the opening 18a of the anode shield 18. The plurality of shield members 184 to 187 may also be moved manually. In addition, the plating unit 10 may also be provided with a moving mechanism (not shown) for moving the plurality of shield members 184 to 187. As the moving mechanism, a known mechanism may be adopted, for example, a motor and a ball screw may be used to implement it. The control device 17 of the plating device can also control the moving mechanism so as to change the opening shape of the anode shield 18 during plating. The distance between each shield member 184 to 187 and between the shield members 184 to 187 and the frame member 182 in the direction perpendicular to the surface of the substrate Wf is preferably arranged sufficiently adjacent to the inter-electrode distance (the distance between the anode 12 and the substrate Wf), but due to the limitation when setting the moving mechanism, it can also be arranged to a certain extent.

[0048] As described above, the anode shield 18 includes a frame member 182 and a plurality of shield members 184 to 187, and the opening 18a of the anode shield 18 is defined by the frame member 182 and the shield members 184 to 187. The anode shield 18 includes: a first shield member (e.g., shield member 184) provided at a first opening side corresponding to a first side (e.g., an upper side) of the substrate Wf, defining a convex portion protruding toward the center of the opening 18a; and a second shield member (e.g., shield member 186) provided at a second opening side corresponding to a second side (e.g., a lower side) of the substrate Wf opposite to the first side, defining a convex portion protruding toward the center of the opening 18a. The first shield member 184 and the second shield member 186 are configured to be movable relative to the frame member 182, and the distance between them can be adjusted. In addition, the anode shield 18 includes: a third shield member (e.g., shield member 185) provided at a third opening side corresponding to a third side (e.g., right side) of the substrate Wf, defining a convex portion protruding toward the center of the opening 18a; and a fourth shield member (e.g., shield member 187) provided at a fourth opening side corresponding to a fourth side (e.g., left side) of the substrate Wf opposite to the third side, defining a convex portion protruding toward the center of the opening 18a. The third shield member 185 and the fourth shield member 187 are configured to be movable relative to the frame member 182, and the distance between them can be adjusted. In the present embodiment, the first to fourth shield members 184 to 187 are configured to be movable in a vertical direction relative to the opening sides respectively arranged.

[0049] As described above, the anode shield 18 is formed, and the mask members 184 to 187 can be moved to adjust the shape of the opening 18a of the anode shield 18. Here, in a polygonal substrate, it is known that when the terminal effect is large, there is a tendency that the final plated film thickness near the vertices of the substrate is smaller than that of the portion between the vertices. In the anode shield 18 of the present embodiment, a convex portion protruding toward the center is formed in the opening 18a by the convex portions 184b to 187b of the mask members 184 to 187 (see Figure 3B , 3C ), even if the mask members 184 to 187 move inward and the area of ​​the opening 18a becomes smaller, the vicinity of the vertex of the opening 18a is not much shielded. Since such an anode mask 18 has such a shape of the opening 18a, the in-plane uniformity of the film plated on the substrate can be improved. In addition, the size and shape of the convex portions 184b to 187b of the plurality of mask members 184 to 187 can be appropriately determined by experiments or simulations in a manner that improves the in-plane uniformity of the plated film.

[0050] Refer again Figure 2 The plating unit 10 includes: a regulation plate 20 for regulating the electric field between the substrate Wf and the anode 12; and a paddle 16 for stirring the plating solution. The regulation plate 20 is disposed between the substrate holder 30 and the anode 12. As a specific example, the lower end of the regulation plate 20 is inserted between a pair of convex parts 28 provided on the bottom surface of the plating tank 14, and the regulation plate 20 is fixed relative to the plating tank 14. In addition, the regulation plate 20 has an arm (not shown) protruding outward near the upper end, Figure 1 In the stocker 124 shown, the paddle 16 may be suspended by hanging the arm on the upper surface of the peripheral wall of the stocker 124. The paddle 16 is disposed between the substrate support 30 and the adjustment plate 20.

[0051] Figure 4A This is a diagram showing an adjustment plate 20 according to one embodiment from the substrate Wf side. Figure 4B This is a diagram showing an adjustment plate 20 and an anode mask 18 according to an embodiment of the present invention from the substrate Wf side. The adjustment plate 20 has a polygonal opening 21 corresponding to the polygonal shape of the substrate Wf. Figure 4A In the example shown, the polygonal opening 21 is substantially square in shape, but is not limited thereto, and has protrusions 20b protruding from the four sides toward the center. Such protrusions are formed not only on the anode mask 18 but also on the adjustment plate 20, thereby further improving the tendency of the plated film thickness to decrease in the area near the corners observed when the terminal effect is large. The protrusions 20b are as shown in FIG. Figure 4AAs in the example shown in the trapezoidal shape, it is preferred that the two sides of the convex portion have an inclination, and the opening size between the convex portions formed on the other side opposite to the polygonal opening 21 is continuously changed. In this way, the degree of electric field shielding near the boundary between the convex portion 20b and other parts is suppressed to cause fluctuations in the plating film thickness distribution, thereby improving the in-plane uniformity of the plating formed on the substrate Wf. In addition, as Figure 4B As shown, in this embodiment, the polygonal opening 21 of the adjustment plate 20 has a size larger than the opening 18a of the anode mask 18. In addition, in this embodiment, the adjustment plate 20 has auxiliary anodes 214 to 217 arranged at each opening edge of the polygonal opening 21. In other words, the plurality of auxiliary anodes 214 to 217 are arranged to correspond to the convex portions 184b to 187b of the plurality of mask members 184 to 187. The polygonal substrate Wf is electrically connected to the auxiliary anodes 214 to 217 via the plating power supply 15 or an auxiliary power supply not shown.

[0052] The control device 17 can adjust the current flowing between the auxiliary anodes 214 to 217 and the substrate Wf by adjusting the voltage applied between the auxiliary anodes 214 to 217 and the substrate Wf. As a specific example, the control device 17 is configured so that the larger the distance between the mask parts 184 to 187 in the anode mask 18, the larger the current flowing between the auxiliary anodes 214 to 217 and the substrate Wf. That is, the control device 17 reduces the distance between the mask parts 184 to 187 in the anode mask 18 and reduces or makes the current flowing between the auxiliary anodes 214 to 217 and the substrate Wf by the so-called terminal effect or the like, assuming that the film thickness of the plated film in the center portion of the substrate Wf is small and the film thickness of the plated film in the peripheral portion of the substrate Wf is large. In addition, the control device 17 increases the distance between the mask parts 184 to 187 in the anode mask 18 and increases the current flowing between the auxiliary anodes 214 to 217 and the substrate Wf, assuming that the film thickness of the plated film in the center of the substrate Wf is large and the film thickness of the plated film in the peripheral portion of the substrate Wf is small. In addition, by pre-adjusting the length of the auxiliary anodes 214 to 217 (the dimension in the direction parallel to the polygonal opening 21 of the adjustment plate 20), the control range of the plated film thickness based on the auxiliary anodes 214 to 217 can be adjusted. For example, when the terminal effect is small, there is a tendency for the plated film thickness to decrease near the convex portion 20b formed on the adjustment plate due to its electric field shielding effect, but by adjusting the length of the auxiliary anodes 214 to 217 corresponding to the shape and length of the convex portion 20b, the plated film thickness near the convex portion 20b can be effectively suppressed from decreasing. By such control, the in-plane uniformity of the plating formed on the substrate Wf can be improved.

[0053] Figure 5A to Figure 5CThe following are schematic diagrams showing the thickness of the plated film when a quadrilateral substrate is plated by the plating device of this embodiment under the conditions of large, medium, and small terminal effects, respectively. Figure 6A to Figure 6C and Figure 5A to Figure 5C Similarly, it is a schematic diagram showing the thickness of the plated film when a quadrilateral substrate is plated by a plating device of a comparative example under the conditions of large, medium and small terminal effects. Figure 5A to Figure 5C and Figure 6A to Figure 6C In the figure, the plated film in the upper right area after the quadrilateral substrate is divided into four parts is shown. The lower left part of the figure corresponds to the center part Ctr of the quadrilateral substrate, and the upper right part of the figure corresponds to the corner part Cor of the quadrilateral substrate. In these figures, the lighter the color, the smaller the film thickness is relative to the average film thickness, and the darker the color, the larger the film thickness is relative to the average film thickness. Fig. 6A As shown in FIG. 1 , in the conventional plating apparatus of the comparative example, when the influence of the terminal effect is large, the film thickness near the corner of the substrate Wf becomes smaller, and the film thickness near the center of the side becomes larger. Figure 6C As shown in FIG. 1 , in the conventional plating apparatus of the comparative example, when the influence of the terminal effect is small, the film thickness in the central portion of the substrate Wf becomes smaller, and the film thickness in the peripheral portion including the corner portion becomes larger. Figure 5A to Figure 5C As shown, in the plating performed by the plating apparatus of the present embodiment, appropriate in-plane uniformity can be obtained even under any of the conditions where the terminal effect is large, medium, or small.

[0054] Next, the substrate holder 30 will be described. Figure 7 is Figure 2 A schematic front view of a substrate holder 30 used in the plating unit 10 is shown. Figure 8 : is a schematic side view of the substrate holder 30. The substrate holder 30 includes a front plate 300 and a rear plate 400. The substrate Wf is held between the front plate 300 and the rear plate 400. In the present embodiment, the substrate holder 30 holds the substrate Wf in a state where one surface of the substrate Wf is exposed.

[0055] The front panel 300 includes a front panel body 310 and an arm 330. The arm 330 has a pair of pedestals 331. Figure 1 The substrate holder 30 is vertically suspended and supported on the upper surface of the peripheral wall of each processing tank shown in the figure. In addition, a connector 332 is provided on the arm portion 330, and the connector 332 is configured to contact with an electric contact point provided on the plating tank 14 when the base 331 is provided on the upper surface of the peripheral wall of the plating tank 14. Thus, the substrate holder 30 is electrically connected to an external power source, and a voltage and a current are applied to the polygonal substrate Wf held by the substrate holder 30.

[0056] The front plate body 310 is roughly rectangular, has a wiring buffer portion 311 and a face portion 312, and has a front 301 and a back 302. The front plate body 310 is mounted on the arm 330 at two locations through the mounting portion 320. An opening portion 303 is provided in the front plate body 310, and the plated surface of the substrate Wf is exposed from the opening portion 303. In the present embodiment, the opening portion 303 is formed into a shape corresponding to the shape of the polygonal substrate Wf. In addition, a mask for electric field adjustment may also be provided at the inner periphery of the opening portion 303 to shield a portion of the outer periphery of the plated surface of the substrate Wf. This is effective when the terminal effect is very large because the seed layer formed on the substrate Wf is extremely thin. As an example, the mask can be formed of a dielectric material such as resin.

[0057] The back plate 400 is substantially rectangular and covers the back side of the substrate Wf. The back plate 400 is fixed by the clamp 340 in a state where the substrate Wf is sandwiched between the back side 302 of the front plate body 310 (more specifically, the face 312). The clamp 340 is configured to rotate around a rotation axis 341 parallel to the faces 301 and 302 of the front plate body 310. However, the clamp 340 is not limited to this example, and may also be configured to reciprocate in a direction perpendicular to the faces 301 and 302 to clamp the back plate 400.

[0058] Fig. 9 This is the rear view of the front panel body. Fig.10 The rear view is an enlarged view showing the corner of the face portion close to the connector. The rear surface 302 of the front panel body 310 has 18 contact areas C1-C18. The contact areas C1-C7, C17, and C18 are arranged in the half area (proximal area, Fig. 9 The contact areas C8-C16 are arranged in the right half of the area on the side of the face 312 away from the connector 332 (the distal area, Fig. 9 In the following description, for convenience, the cables arranged in the far region are referred to as the first group of cables, and the cables arranged in the near region are referred to as the second group of cables.

[0059] like Fig.10As shown, each contact area C1-C18 includes a contact (contact component) 370 for supplying power to the substrate Wf. The contact 370 is arranged along each side of the opening 303 of the front plate 300. In other words, the contact 370 is arranged along each side of the polygonal substrate Wf. The contact 370 in each contact area C1-C18 is supplied with power from the outside via the cables L1-L18, respectively. In addition, in the following description, when it is not necessary to distinguish between the cables, there is a case where the cables L1-L18 are collectively referred to as cables L. In addition, there is also a case where an arbitrary cable is referred to as cable L.

[0060] The first end of the cable L1-L18 is connected to the connector 332 provided at one end of the arm 330, and more specifically, is electrically connected to individual contacts or a plurality of common contacts (not shown) in the connector 332. The cable L1-L18 can be electrically connected to an external power source (power circuit, power device, etc.) via each contact of the connector 332.

[0061] The cables L1-L7 are arranged in parallel on the same plane and introduced into the cable passage 365, and are arranged along the side of the opening 303 on the connector 332 side. The cables do not overlap each other in the thickness direction of the face 312. Therefore, the thickness of the face 312 and the front plate 300 can be suppressed.

[0062] The electrical connection between the cable L and the contact 370 in each contact area is performed as follows. Taking the cable L1 as an example, the front end (second end) of the cable L1 is exposed by removing the coating 602 to expose the core wire (conductive wire) 601. The front end of the cable L1 is introduced into the wiring groove of the seal holder 363 near the contact C1, and is pressed together with the contact 370 by screws (fastening components) 511 at four locations in the contact area C1. In other words, the screws (fastening components) 511 and the seal holder 363 clamp the core wire 601 of the cable L1 together with the contact 370. As a result, the cable L1 is electrically connected to the contact 370. If the substrate holder 30 holds the substrate Wf, the contact 370 contacts the substrate Wf, and power is supplied to the substrate Wf from an external power source via the cable L1 and the contact 370. The other contact regions C2 to C18 are similarly configured, and power is supplied to the substrate Wf from the contacts 370 at 18 locations.

[0063] As described above, the substrate holder 30 of the present embodiment is configured such that the contacts 370 are provided on each side of the polygonal substrate Wf, and power is supplied to the substrate Wf from the contacts 370 provided on each side. Thus, a plated film is formed on the surface of the substrate Wf.

[0064] The above describes the procedure for plating a quadrilateral substrate Wf, but the present invention is not limited thereto, and a triangular or pentagonal substrate Wf or more can also be plated in the same procedure. Even in such a case, the anode mask can be configured as a plurality of mask parts having a convex portion defined in the center of the opening edge corresponding to the shape of the substrate, and the distance between the plurality of mask parts can be adjusted.

[0065] (Variation Example)

[0066] Figures 11A to 11C This is a diagram showing a modified anode shield 18A from the substrate Wf side. The modified anode shield 18A is similar to the anode shield 18 of the above-mentioned embodiment, and includes a frame member 182 that defines a polygonal opening corresponding to the polygonal shape of the substrate Wf. In addition, the anode shield 18A includes a plurality of shield members 184A to 187A that are arranged adjacent to the frame member 182 and are movable relative to the frame member 182. Figures 11A to 11C In the figure, for the convenience of display, the frame member 182 and the four mask members 184A to 187A are shaded. The four mask members 184A to 187A are of the same shape and are arranged in a state where each is rotated 90 degrees. Figures 11A to 11C In FIG. 1 , the mask member 184A disposed on the upper left side of the opening 182a is given a hatching different from that of the other mask members 185A to 187A.

[0067] The mask members 184A to 187A of the modified example are respectively arranged at the corners of the opening 182a, and define a convex portion protruding toward the center of the opening 182a on two continuous opening sides of the opening 182a. Figures 11A to 11C In the example shown, the mask members 184A to 187A have: convex portions 184Ab to 187Ab, which define the convex portion along the opening 182a; and concave portions 184Aa to 187Aa, which are provided at positions corresponding to the corners of the opening 182a and are recessed toward the periphery than the convex portions 184Ab to 187Ab. The mask members 184A to 187A are configured to be movable relative to the frame member 182, and define the opening 18Aa of the anode mask 18A together with the frame member 182. Figures 11A to 11C In the example shown, the mask members 184A to 187A can move linearly relative to the frame member 182 in a direction inclined at 45 degrees in the vertical and horizontal directions relative to the paper surface. Fig.11A In the example shown, the mask members 184A to 187A are located outside and do not overlap with the opening 182a of the frame member 182, and the opening 182a of the frame member 182 becomes the opening 18Aa of the anode mask 18A. From this state, if the plurality of mask members 184A to 187A are moved toward the center relative to the frame member 182, as shown in FIG. Fig. 11B As shown in FIG. 1 , the protrusions 184Ab to 187Ab protrude into the opening 182a of the frame member 182, respectively. Fig. 11B In the example shown, the opening defined by a portion of the frame member 182 and a portion of the convex portions 184Ab to 187Ab of the mask members 184A to 187A becomes the opening of the anode mask 18. At this time, a convex portion protruding toward the center of the opening 18Aa is defined in the central portion of the opening edge by the convex portions 184Ab to 187Ab of the adjacent mask members 184A to 187A. For example, a convex portion protruding toward the center of the opening is defined in the central portion of the upper side by the convex portion 184Ab of the mask member 184A disposed on the upper left and the convex portion 185Ab of the mask member 185A disposed on the upper right. Then, if the plurality of mask members 184A to 187A are further moved toward the center relative to the frame member 182, as shown in FIG. Fig. 11C As shown in FIG. 1 , the convex portions 184Ab to 187Ab and the concave portions 184Aa to 187Aa of the mask members 184A to 187A protrude into the opening 182a of the frame member 182. Fig. 11C In the example shown, the opening defined by the plurality of mask members 184A to 187A serves as the opening 18a of the anode mask 18. Fig.11A , Fig. 11B , Fig. 11C Each of these diagrams shows an example of the state of the opening 18a of the anode mask 18. The positions of the plurality of mask members 184A to 187A may also change smoothly.

[0068] Even in such a modified anode mask 18A, the in-plane uniformity of the plating formed on the substrate Wf can be improved by changing the opening shape, as in the anode mask 18 of the above-described embodiment. In addition, the plurality of mask members 184A to 187A may be moved manually or by a moving mechanism (not shown).

[0069] In the above-mentioned embodiment and modification, the anode shield 18 and 18A have a frame member 182 corresponding to the shape of the substrate Wf. However, the anode shield 18 and 18A may not have such a frame member, and may be configured such that the side portions 184a to 187a of the plurality of shield members 184 to 187 are formed to be longer, etc., so that the opening 18a is defined by the plurality of shield members 184 to 187 and 184A to 187A.

[0070] The present invention can be described as the following aspects.

[0071] [Method 1] According to method 1, a plating device is proposed, comprising: a plating tank; a substrate holder configured to hold a polygonal substrate; an anode arranged in the plating tank so as to be opposite to the substrate held by the substrate holder; and an anode mask defining an opening corresponding to the outer shape of the polygonal substrate, wherein the anode mask comprises: a first mask component defining a first convex portion protruding toward the center of the opening at a central portion of a first opening side corresponding to the first side of the polygonal substrate in the opening; and a second mask component defining a second convex portion protruding toward the center of the opening at a central portion of a second opening side corresponding to the second side of the polygonal substrate in the opening, wherein the anode mask is configured to be able to adjust the mutual distance between the first mask component and the second mask component. According to method 1, the opening shape of the anode mask can be adjusted by adjusting the mutual distance between the first mask component and the second mask component, thereby improving the in-plane uniformity of the film plated on the polygonal substrate.

[0072] [Method 2] According to method 2, on the basis of method 1, the first mask component is configured to be arranged on the first opening edge and can be moved in a direction perpendicular to the first opening edge, and the second mask component is configured to be arranged on the second opening edge and can be moved in a direction perpendicular to the second opening edge.

[0073] [Method 3] According to method 3, on the basis of method 2, the anode shield further comprises: a third shield member, which is arranged at a third opening side of the opening corresponding to the third side of the polygonal substrate, and defines a third convex portion protruding toward the center of the opening at the central portion of the third opening side; and a fourth shield member, which is arranged at a fourth opening side of the opening corresponding to the fourth side of the polygonal substrate, and defines a fourth convex portion protruding toward the center of the opening at the central portion of the fourth opening side, and the anode shield is configured to be able to adjust the mutual distance between the third shield member and the fourth shield member. According to method 3, the opening shape of the anode shield can be adjusted by adjusting the mutual distance between the first to fourth shield members, thereby improving the in-plane uniformity of the film plated on the polygonal substrate.

[0074] [Method 4] According to method 4, on the basis of method 1, the first mask component is arranged at the first corner of the opening, and two consecutive opening edges in the opening define a convex portion protruding toward the center of the opening; the second mask component is arranged at the second corner of the opening, and two consecutive opening edges in the opening define a convex portion protruding toward the center of the opening.

[0075] [Mode 5] According to Mode 5, in addition to Modes 1 to 4, the first convex portion and the second convex portion are trapezoidal in shape that becomes narrower toward the center of the opening.

[0076] [Method 6] According to method 6, on the basis of methods 1 to 5, the anode mask has a frame member, the frame member defines a polygonal opening corresponding to the outer shape of the polygonal substrate, the first mask member and the second mask member are arranged adjacent to the frame member, and together with the frame member, define the opening of the anode mask.

[0077] [Method 7] According to method 7, on the basis of methods 1 to 6, a regulation plate is provided between the anode support and the substrate support, and the regulation plate has a first auxiliary anode arranged corresponding to the first side of the first mask member, and a second auxiliary anode arranged corresponding to the second side of the second mask member. According to method 7, the first auxiliary anode and the second auxiliary anode can be used to further improve the in-plane uniformity of the plated film.

[0078] [Method 8] According to method 8, on the basis of method 7, a control device is provided, and the control device allows current to flow between the first auxiliary anode and the second auxiliary anode and the polygonal substrate in such a way that the greater the distance between the first mask part and the second mask part, the greater the current flowing through the first auxiliary anode and the second auxiliary anode.

[0079] [Method 9] According to method 9, a plating method is proposed, which is a method for plating the polygonal substrate by allowing current to flow between an anode and a polygonal substrate in a plating device, the plating method comprising the following steps: in an anode mask defining an opening corresponding to the outer shape of the polygonal substrate, adjusting the mutual distance between a first mask component and a second mask component of the anode mask, wherein the first mask component defines a first convex portion protruding toward the center of the opening at a central portion of a first opening side corresponding to the first side of the polygonal substrate in the opening, and the second mask component defines a second convex portion protruding toward the center of the opening at a central portion of a second opening side corresponding to the second side of the polygonal substrate in the opening; and allowing current to flow between the anode and the polygonal substrate. According to method 9, the opening shape of the anode mask can be adjusted by adjusting the mutual distance between the first mask component and the second mask component, thereby improving the in-plane uniformity of the film plated on the polygonal substrate.

[0080] [Method 10] According to method 10, on the basis of method 9, the plating device includes an adjustment plate disposed between the anode support and the substrate support, the adjustment plate includes a first auxiliary anode configured corresponding to the first side of the first mask component, and a second auxiliary anode configured corresponding to the second side of the second mask component, and the plating method includes the following steps: causing current to flow between the first auxiliary anode and the second auxiliary anode and the polygonal substrate in such a manner that the greater the distance between the first mask component and the second mask component, the greater the current flowing through the first auxiliary anode and the second auxiliary anode. According to method 10, the first auxiliary anode and the second auxiliary anode can be used to further improve the in-plane uniformity of the plated film.

[0081] The above describes the embodiments of the present invention, but the embodiments of the above invention are for easy understanding of the present invention and are not intended to limit the present invention. The present invention can be changed and improved without departing from its main purpose, and the present invention also includes its equivalents. In addition, within the scope of at least a part of the above-mentioned problem being able to be solved or the scope of at least a part of the effect being achieved, each constituent element described in the claims and the specification can be arbitrarily combined or omitted.

[0082] Description of Reference Numerals

[0083] 10…plating unit; 12…anode; 13…anode holder; 17…control device; 18, 18A…anode mask; 18a, 18Aa…opening; 20…adjustment plate; 21…polygonal opening; 30…substrate holder; 184~187, 184A~187A…mask component; 184a~187a…edge; 184b~187b…convex portion; 184Aa~187Aa…concave portion; 184Ab~187Ab…convex portion; 214~217…auxiliary anode; Wf…polygonal substrate.

Claims

1. A plating device, characterized in that: have: Plating tank; a substrate holder configured to hold a polygonal substrate; an anode, arranged in the plating tank so as to be opposite to the substrate held by the substrate holder; as well as an anode mask defining an opening corresponding to the outer shape of the polygonal substrate, Wherein, the anode shield has: A first mask member defines a first convex portion protruding from the first opening edge toward the center of the opening at a central portion of a first opening edge corresponding to the first side of the polygonal substrate in the opening; and The second mask member defines a second convex portion protruding from the second opening edge toward the center of the opening at a central portion of a second opening edge corresponding to the second edge of the polygonal substrate in the opening, The anode shield is configured so that a distance between the first shield member and the second shield member can be adjusted.

2. The plating device according to claim 1, characterized in that: The first mask member is configured to be disposed on the first opening side and is movable in a direction perpendicular to the first opening side. The second cover member is arranged at the second opening side and is movable in a direction perpendicular to the second opening side.

3. The plating device according to claim 2, characterized in that: The anode shield further comprises: A third masking member is disposed at a third opening edge of the opening corresponding to a third edge of the polygonal substrate, and defines a third convex portion protruding from the third opening edge toward the center of the opening at a central portion of the third opening edge; as well as a fourth masking member disposed at a fourth opening edge of the opening corresponding to a fourth edge of the polygonal substrate, and defining a fourth convex portion protruding from the fourth opening edge toward the center of the opening at a central portion of the fourth opening edge; The anode shield is configured so that a distance between the third shield member and the fourth shield member can be adjusted.

4. The plating device according to claim 1, characterized in that: The first mask member is disposed at a first corner of the opening, and two continuous opening edges in the opening define a convex portion protruding from the two opening edges toward the center of the opening. The second mask member is disposed at a second corner of the opening, and two continuous opening sides in the opening define a convex portion that protrudes from the two opening sides toward the center of the opening.

5. The plating device according to any one of claims 1 to 4, characterized in that: The first convex portion and the second convex portion are trapezoidal in shape and narrow toward the center of the opening.

6. The plating device according to any one of claims 1 to 4, characterized in that: The anode mask includes a frame member defining a polygonal opening corresponding to the outer shape of the polygonal substrate. The first mask member and the second mask member are disposed adjacent to the frame member, and define the opening of the anode mask together with the frame member.

7. The plating device according to any one of claims 1, 2 and 4, characterized in that: An adjustment plate is provided between the anode support and the substrate support, The adjustment plate includes a first auxiliary anode disposed corresponding to the first side of the first shield member, and a second auxiliary anode disposed corresponding to the second side of the second shield member.

8. The plating device according to claim 7, characterized in that: A control device is provided for causing current to flow between the first auxiliary anode and the second auxiliary anode and the polygonal substrate so that the current flowing through the first auxiliary anode and the second auxiliary anode increases as the distance between the first shield member and the second shield member increases.

9. A plating method, comprising: plating a polygonal substrate by passing an electric current between an anode and the polygonal substrate in a plating device, The plating method is characterized in that it comprises the following steps: In an anode mask defining an opening corresponding to the outer shape of the polygonal substrate, a distance between a first mask member and a second mask member of the anode mask is adjusted, wherein: The first mask component defines a first convex portion protruding from the first opening edge toward the center of the opening at a central portion of a first opening edge in the opening corresponding to the first edge of the polygonal substrate, and the second mask component defines a second convex portion protruding from the second opening edge toward the center of the opening at a central portion of a second opening edge in the opening corresponding to the second edge of the polygonal substrate; as well as A current is caused to flow between the anode and the polygonal substrate.

10. The plating method according to claim 9, characterized in that: The plating device includes an adjustment plate arranged between the anode support and the substrate support, The adjustment plate includes a first auxiliary anode disposed corresponding to the first side of the first shield member and a second auxiliary anode disposed corresponding to the second side of the second shield member. The plating method includes the following steps: causing current to flow between the first auxiliary anode and the second auxiliary anode and the polygonal substrate in such a manner that the greater the distance between the first mask member and the second mask member, the greater the current flowing through the first auxiliary anode and the second auxiliary anode.

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