Board, plating apparatus, and method for manufacturing a board

Abstract

The present invention relates to a plate, a plating apparatus, and a method for manufacturing a plate. Local anisotropy in the distribution of holes formed in the plate is suppressed. The present invention provides a plate disposed between a substrate and an anode in a plating bath. The plate has a plurality of circular holes respectively on three or more reference circles that are concentric and have different diameters, and the centers of three of the holes respectively disposed on three adjacent reference circles do not align on any radius of the plate.

Description

Technical Field

[0001] The present invention relates to a plate, a plating apparatus, and a method for manufacturing a plate. Background Art

[0002] Conventionally, wirings, bumps (protrusion-shaped electrodes), etc. have been formed on the surfaces of substrates such as semiconductor wafers and printed circuit boards. As a method for forming such wirings and bumps, a plating method is known.

[0003] In a plating apparatus used in the plating method, it is known to dispose a plate for electric field adjustment having a plurality of holes between a circular substrate such as a wafer and an anode (see, for example, Patent Documents 1 and 2).

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2004-225129

[0005] Patent Document 2: International Publication No. 2004 / 009879

[0006] As the seed layer formed on the substrate becomes thinner, a so-called end effect may occur. The end effect refers to a phenomenon in which the resistance of the central portion of the substrate becomes higher, the film thickness of the edge portion of the substrate near the electrode becomes thicker, and the film thickness of the central portion of the substrate becomes thinner. By forming the plate from an electrically insulating material, the influence of the end effect can be reduced. However, when the distribution density (or porosity) of the holes formed in the plate is not uniform in each region of the plate, the arrangement position of the holes may have an adverse effect on the plating film thickness distribution. Summary of the Invention

[0007] The present invention has been made in view of the above problems. One of its objects is to suppress local anisotropy in the distribution of holes formed in a plate.

[0008] According to one aspect of the present invention, there is provided a plate disposed between a substrate and an anode in a plating bath. The plate has a plurality of circular holes on each of three or more reference circles that are concentric and have different diameters, and the centers of three of the holes respectively disposed on three adjacent reference circles do not align on any radius of the plate.

[0009] According to another aspect of the present invention, there is provided a plating apparatus. The plating apparatus includes the above-described plate and a plating bath that houses the plate.

[0010] According to another aspect of the present invention, there is provided a method for manufacturing a plate disposed between a substrate and an anode in a plating bath and having a plurality of circular holes. The method for manufacturing the plate includes: determining a radius of a region where a plurality of the holes are to be formed on the plate, i.e., a region radius, a hole diameter of the plurality of the holes, and a target porosity in the region within the region radius; dividing the region into a plurality of divided annular regions having a constant width based on the region radius, the hole diameter, and the target porosity; and forming the plurality of holes on reference circles respectively located in the plurality of divided regions of the plate such that centers of three of the holes respectively disposed on three adjacent reference circles are not arranged on any radius. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 FIG. is a schematic diagram showing an example of a plating apparatus including the plate according to the present embodiment.

[0012] Figure 2 FIG. is a front view of the plate.

[0013] Figure 3 FIG. is a flowchart showing a manufacturing process of the plate.

[0014] Figure 4 FIG. is a schematic diagram showing a region where holes are formed divided according to the region radius of the plate.

[0015] Figure 5 FIG. is a schematic diagram for explaining the relationship between the circumferential pitch and the radial pitch of a plurality of holes.

[0016] Reference Numeral Explanation: CP... circumferential pitch; Pr k ... number of holes; θ int_k ... initial angle; Rref k ... reference circle radius; Cref k ... reference circle; AP... difference; N k ... divided region; D pore ... hole diameter; P... target porosity; RP... radial pitch; R... region radius; Div... number of divided regions; 10... plate; 100... plating apparatus; 101... plating bath; 102... substrate. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings described below, the same or corresponding components are denoted by the same reference numerals and redundant descriptions are omitted. Figure 1 FIG. is a schematic diagram showing an example of a plating apparatus including the plate according to the present embodiment. As Figure 1 shown, the plating apparatus 100 according to the present embodiment is a so-called face-down type or cup type plating apparatus 100.

[0018] The plating apparatus 100 includes a plating bath 101, a substrate holder 103, and a plating solution storage tank 104. The substrate holder 103 is configured to hold a substrate 102 such as a wafer with its plating surface facing downward. The plating apparatus 100 has a motor 111 that rotates the substrate holder 103 in the circumferential direction. An anode 110 is disposed in the plating bath 101 so as to face the substrate 102.

[0019] The plating apparatus 100 further includes a plating solution receiving tank 108. The plating solution in the plating solution storage tank 104 is supplied from the bottom of the plating bath 101 into the plating bath 101 by a pump 105 through a filter 106 and a plating solution supply pipe 107. The plating solution overflowing from the plating bath 101 is received by the plating solution receiving tank 108 and returned to the plating solution storage tank 104.

[0020] The plating apparatus 100 further includes a power source 109 connected to the substrate 102 and the anode 110. By applying a predetermined voltage between the substrate 102 and the anode 110 while the motor 111 rotates the substrate holder 103, a plating current flows between the anode 110 and the substrate 102, and a plating film is formed on the plating surface of the substrate 102.

[0021] A plate 10 is disposed between the substrate 102 and the anode 110. Figure 2 is a front view of the plate 10. As Figure 2 shown, the plate 10 has a plurality of circular holes 12. The holes 12 penetrate between the front surface and the back surface of the plate 10, constituting a path for the plating solution and ions in the plating solution to pass through.

[0022] In the plate 10 according to the present embodiment, the plurality of holes 12 are arranged on three or more virtual reference circles that are concentric and have different diameters. In other words, the plurality of holes 12 are arranged to be dispersed in the radial direction of the plate 10. And, in the plate 10, the holes 12 are arranged such that the centers of three holes 12 respectively arranged on adjacent three reference circles do not align on any radius of the plate 10. In other words, three holes 12 separated from each other in the radial direction of the plate 10 among the plurality of holes 12 are not continuously arranged on any radius of the plate 10. Thereby, the concentration of the holes 12 on any radius of the plate 10 is suppressed, so that the local anisotropy of the distribution of the holes 12 can be suppressed.

[0023] In addition, in the plate 10, it is preferable that the plurality of holes 12 are arranged at equal intervals in the circumferential direction on the reference circle. Thereby, the holes 12 can be dispersed in the circumferential direction of the reference circle. In addition, the term "equal intervals" here is not limited to completely equal intervals mathematically, and may also include some deviations caused by errors such as machining.

[0024] Further, in the plate 10, it is preferable that the difference in diameter between any reference circle and the adjacent reference circle is constant. In other words, it is preferable that the holes 12 are arranged at equal intervals in the radial direction. Thereby, the holes 12 can be arranged dispersedly in the radial direction of the reference circle. In addition, the term "equal intervals" here is not limited to completely equal intervals mathematically, and may also include some deviations caused by errors such as machining.

[0025] Next, a method for manufacturing the plate 10 will be described. Figure 3 FIG. is a flowchart showing the manufacturing process of the plate 10. First, a plate 10 without the holes 12 that will become the material of the plate 10 is prepared (step S201). The plate 10 without the holes 12 is made of an electrically insulating material, such as PVC (polyvinyl chloride), etc. Next, the target porosity P of the plate 10 is set (step S202). Here, the porosity can be expressed by "the total area of the plurality of holes 12 / the area of the region where the holes 12 are formed (region area)". In addition, the target porosity P refers to the target porosity used in the manufacturing process of the plate 10. The target porosity P can be appropriately obtained through experiments or simulations in advance. Specifically, regarding the target porosity P, since it is known that there is an appropriate target porosity P according to the distance between the substrate 102 and the plate 10, it can be based on Figure 1 the distance between the substrate 102 and the plate 10 in the plating apparatus 100 shown, and an appropriate target porosity P can be obtained through experiments or simulations.

[0026] Next, the hole diameter D of the holes 12 formed on the plate 10 pore and the region radius R are set (step S203). The hole diameter D pore can be arbitrarily set based on empirical rules or the like as long as it is a size that can be machined. The region radius R is the radius of the circular region on the plate where the holes 12 are formed, and can be arbitrarily set based on, for example, Figure 1 the size of the plating bath 101, the substrate 102, or the anode 110 shown. In addition, in the present embodiment, when simply referred to as "radial direction" or "circumferential direction", it means the "radial direction of the region radius R" or the "circumferential direction of the region radius R".

[0027] After setting the target porosity P, the hole diameter D pore and the region radius R, the number of divided regions Div is calculated (step S204). Here, the divided region refers to an annular region having a constant width, and is a region where three or more reference circles that are concentric and have different diameters are arranged. Therefore, by determining the number of divided regions Div, it is determined to what extent the holes 12 are arranged dispersedly in the region radius R direction.

[0028] Figure 4It is a schematic diagram showing the area where the hole 12 is formed, divided according to the area radius R of the plate 10. In the illustrated example, the number of divided areas Div is 6, and the divided areas N are shown in order from the center side of the area radius R toward the outside 1 to the divided area N 6 . The reference circle Cref k indicates the positions where a plurality of holes 12 are arranged, and is a circle formed by connecting the central points of the widths of the respective divided areas N k . In addition, in the present embodiment, "k" is an algebraic expression representing the number of the divided areas (1 to 6 in the present embodiment). The divided area N 1 includes the center of the area radius R and is circular, different from the other divided areas N 2 to the divided area N 6 . The reference circle radius Rref k is the radius based on the center of the area radius R of each reference circle Cref k .

[0029] As Figure 4 shown, the area radius R corresponds to the outside diameter of the largest divided area N k (divided area N 6 in the illustrated example). In addition, the difference AP of the divided area radius R is the radial difference between each divided area N k and the adjacent divided area N k+1 (or divided area N k－1 ). In other words, the difference AP of the divided area radius R can also be referred to as the width of each divided area N k .

[0030] The hole 12 of the plate 10 has a hole diameter D pore . The respective hole areas S pore of the holes 12 can be represented by (hole diameter D pore / 2)^2*π. The holes 12 on the reference circle Cref k of each divided area N k are arranged at positions at an initial angle θ int_k with respect to an arbitrary diameter, and are arranged separately at an angular interval θ pitch_k from the hole 12. Regarding the initial angle θ int_k and the angular interval θ pitch_k , it will be described in detail later.

[0031] Figure 5 is a schematic diagram for explaining the relationship between the circumferential pitch and the radial pitch of a plurality of holes 12. As Figure 5 shown, the circumferential pitch CP of the plurality of holes 12 corresponds to the reference circle Cref of each divided area kThe circumferential separation distance of the plurality of holes 12 disposed thereon. In addition, the radial pitch RP of the plurality of holes 12 corresponds to the separation distance in the direction of the region radius R of the plurality of holes 12 disposed on the reference circle Cref k of each divided region N k Here, in order to evenly disperse the plurality of holes 12 on the plate 10, it is preferable that the circumferential pitch CP and the radial pitch RP of the plurality of holes 12 disposed on the reference circle Cref k of each divided region N k are the same or approximate.

[0032] Therefore, by setting the circumferential pitch CP and the radial pitch RP of the plurality of holes 12 to be the same, the number of divided regions Div can be calculated according to the target porosity P, the pore diameter D pore and the region radius R. Specifically, the number of divided regions Div can be expressed by the following formula.

[0033] Number of divided regions Div = ROUND(SQRT((4 * region radius R^2 * target porosity P) / (pore diameter D pore ^2 * π))

[0034] Thus, the number of divided regions Div with an approximate circumferential pitch CP and radial pitch RP can be calculated. In addition, in the present embodiment, the Round function is used for rounding to make the number of divided regions Div an integer. However, it is not limited thereto, and any function for making the calculation result an integer can also be used.

[0035] Next, the difference AP of the region radius R of the divided regions, the area S of each divided region k , the number of holes Pr in each divided region k , and the reference circle radius Rref of each divided region k (step S205) are calculated. In the present embodiment, the width of each divided region N k is the same, and the width is equal to the difference AP. In this way, the difference AP can be expressed by (region radius R / number of divided regions Div) and can be calculated based on the region radius R and the number of divided regions Div.

[0036] If the difference AP is determined, the area S of each divided region can be calculated k . Specifically, the area S of the divided region k can be expressed by (difference AP * (k - 0.5))^2 * π - (difference AP * (k - 1.5))^2 * π and can be calculated based on the difference AP.

[0037] The number of holes Pr in each divided region can be calculated based on the area S of each divided region k , the target porosity P, and the pore diameter D pore ​k Specifically, the number of holes Pr in each divided area k can be expressed by the following formula.

[0038] The number of holes Pr in each divided area k = ROUND((the area S of each divided area k * the target porosity P) / the hole area S pore )

[0039] In addition, in this embodiment, by using the Round function for rounding, the number of holes Pr in each divided area k becomes an integer. It is not limited to this, and any function that integerizes the calculation result can also be used.

[0040] The reference circle radius Rref can be calculated based on the difference AP of the radius R of the divided area k Specifically, the reference circle radius Rref k can be expressed by (the difference AP * (k - 0.5)).

[0041] As described above, through the process of step S205, the number of holes Pr of the holes 12 formed in each divided area N k is calculated. k However, the number of holes Pr in the divided area N k is integerized halfway through the calculation. In addition, in order to calculate the number of holes Pr in each divided area N k , the area S of each divided area used k is derived based on the integerized number of divided areas Div. Therefore, there may be a difference between the total hole area S k calculated based on the number of holes Pr in each divided area k (= the number of holes Pr in each divided area N k * the hole area S act ) and the theoretically total hole area S k calculated based on the target porosity P. Therefore, calculate the error between the total hole area S k (the total area of the holes 12) calculated based on the number of holes Pr in one divided area N pore and the theoretically total hole area S theo (theoretically the total area of the holes 12) calculated based on the target porosity P in the same divided area N k . Specifically, in this embodiment, the theoretically total hole area S k is calculated for each divided area N act and the error from the integerized number of holes Pr k is calculated theo (theoretically the total area of the holes 12). k Specifically, in this embodiment, the theoretically total hole area S theo is calculated for each divided area N kCalculated total hole area S act Ratio (step S206). Specifically, this ratio is represented by (total hole area S act / theoretically total hole area S theo * 100).

[0042] Next, based on whether the error between the calculated total hole area S act and the total hole area S theo is equal to or greater than a specified value, if it is equal to or greater than the specified value, the number of holes Pr k of the holes 12 in this divided region N k is increased and the hole diameter D pore is reduced. Specifically, in the present embodiment, when the error between the total hole area S theo and the total hole area S act is 2% or more (step S207, YES), the number of holes Pr k of the holes 12 in this divided region N k is made 2.25 times and the hole diameter D pore is reduced to 2 / 3 (step S208). When the value is a decimal when making the number of holes Pr k 2.25 times, it can also be rounded to an integer using any function. Thus, by making the holes 12 smaller and increasing the number in this divided region N k , the total hole area S act can be made closer to the total hole area S theo . In addition, the increase in the number of holes Pr k and the reduction in the hole diameter D pore at this time can be performed at any magnification, but it is preferably a magnification at which the porosity calculated based on the number of holes Pr k and the hole diameter D pore does not change before and after the calculation.

[0043] In step S207, when the error between the total hole area S theo and the total hole area S act is less than 2% (step S207, NO), the process proceeds to step S209.

[0044] Through the processing of steps S202 to S208, the number of divided regions Div, that is, the number of arrangements of the holes 12 in the radial direction and the radial pitch RP, and the number of circumferential arrangements of the holes 12 on the reference circle Cref k of each divided region are determined. Next, the arrangement angle of the holes 12 on each reference circle Cref k can be determined. Specifically, the angular interval θ k and the initial angle θ pitch_k of the holes 12 arranged in each divided region N int_k(Step S209). First, the angular interval θ of the holes 12 pitch_k is represented by (360° / the number of holes Pr in each divided area k ).

[0045] Next, the calculation method of the initial angle θ int_k will be described. In the present embodiment, the initial angle θ int_k refers to the angle of the hole 12 with respect to an arbitrary radius of the reference circle Cref k . The plurality of holes 12 formed on the plate 10 are arranged on the reference circle at an angular interval θ pitch_k with respect to the hole 12 serving as the reference. In the present embodiment, the initial angle θ int_k is calculated such that the centers of the three holes 12 respectively arranged on three adjacent reference circles Cref k do not align on an arbitrary radius. Specifically, for example, the initial angle θ k of the holes 12 respectively arranged in the divided area N k+2 to the divided area N int_k is calculated such that the holes 12 respectively arranged in the reference circle Cref k of the divided area N k to the reference circle Cref k+2 of the divided area N k+2 do not align on the same radius.

[0046] In the present embodiment, as an example, the initial angle θ 1 of the divided area N 1 is set to the angular interval θ pitch_1 , and the initial angle θ 2 of the divided area N 2 is set to (angular interval θ pitch_1 + initial angle θ 1 / 2). Then, the initial angle θ 3 of the divided area N 3 is set to (angular interval θ pitch_1 +(initial angle θ 1 + initial angle θ 2 ) / 2). That is, the initial angle θ k of any divided area N i can be calculated by the following formula.

[0047]

Formula 1

[0048]

[0049] In addition, as another example, the initial angle θ 1 of the divided area N 1 is set to the angular interval θpitch_1 , set the initial angle θ of the divided region N 2 to the angular interval θ 2 . Set the initial angle θ of the divided region N pitch_2 to (angular interval θ 3 +(initial angle θ 3 +(initial angle θ pitch_3 )) / 2). Additionally, set the initial angle θ of the divided region N 1 to the angular interval θ 2 . Next, set the initial angle θ of the divided region N 4 to (angular interval θ 4 +(initial angle θ pitch_4 +(initial angle θ 5 +(initial angle θ 5 +(initial angle θ pitch_5 +(initial angle θ 1 +(initial angle θ 2 +(initial angle θ 3 +(initial angle θ 4 ))))) / 2). That is, the initial angle θ of any divided region N k can be calculated by the following formula when i = 2n. i

[0050]

Formula 2

[0051] θi = θpitch_i

[0052] Additionally, when i = 2n + 1, the initial angle θ of any divided region N k can be calculated by the following formula. i

[0053]

Formula 3

[0054]

[0055] If the hole 12 is arranged on the reference circle Cref int_k of each divided region N pitch_k with the initial angle θ and the angular interval θ calculated by the above two calculation examples, then the centers of the three holes 12 arranged on the adjacent three reference circles Cref k will not be arranged on any radius of the plate 10. In addition, the above Formulas 1 to 3 are examples, and any initial angle θ can be adopted such that the centers of the three holes 12 arranged on the adjacent three reference circles Cref k are not arranged on any radius. k k int_k .

[0056] When calculating the initial angle θ of each divided region N k ​​​​​int_k and an angular interval θ pitch_k After that, based on the parameters calculated through steps S202 to S209, from the divided area N on the center side of the plate 10 k i.e., the divided area N 1 holes 12 are sequentially formed (step S210).

[0057] As described above, for the plate 10 according to the present embodiment, the centers of the three holes 12 respectively arranged on three adjacent reference circles Cref k are not arranged on any radius of the plate 10, so it is possible to suppress the holes 12 from being densely arranged on any radius, and thus it is possible to suppress the local anisotropy of the distribution of the holes 12.

[0058] In addition, on the plate 10, a plurality of holes 12 are arranged at equal intervals in the circumferential direction on the reference circle Cref k so it is possible to suppress the holes 12 from being densely arranged on the reference circle Cref k and it is possible to suppress the local anisotropy of the distribution of the holes 12.

[0059] Moreover, on the plate 10, the diameter of any reference circle Cref k on which the holes 12 are arranged and the diameter of the adjacent reference circle Cref k+1 have a constant difference. In other words, the holes 12 are arranged at equal intervals in the radial direction, so it is possible to suppress the holes 12 from being densely arranged in the radial direction, and it is possible to suppress the local anisotropy of the distribution of the holes 12.

[0060] The embodiments of the present invention have been described above, but the above-described embodiments of the invention are for easily understanding the content of the present invention and do not limit the present invention. Of course, the present invention can be changed and improved without departing from its gist, and the present invention includes its equivalents. In addition, within the scope of being able to solve at least a part of the above problems, or within the scope of achieving at least a part of the effects, any combination or omission of the respective constituent elements described in the claims and the specification can be made.

[0061] Some aspects disclosed in this specification are described below.

[0062] According to the first aspect, a plate disposed between a substrate and an anode in a plating bath is provided. The plate has a plurality of circular holes respectively on three or more concentric reference circles with different diameters, and the centers of the three holes respectively disposed on three adjacent reference circles are not arranged on any radius of the plate.

[0063] According to the first aspect, since the centers of the three holes respectively arranged on three adjacent reference circles are not arranged on any radius, it is possible to suppress the holes from being densely arranged on any radius, and thus it is possible to suppress the local anisotropy of the distribution of the holes.

[0064] The gist of the second method is that, in the plate of the first method, a plurality of the above-mentioned holes are arranged at equal intervals in the circumferential direction on the above-mentioned reference circle.

[0065] According to the second method, since a plurality of holes are arranged at equal intervals in the circumferential direction on the reference circle, it is possible to suppress the holes from being densely arranged on the reference circle, and it is possible to suppress the local anisotropy of the distribution of the holes.

[0066] The gist of the third method is that, in the plate of the first method or the second method, the difference in diameter between any of the above-mentioned reference circles and the diameter of the adjacent above-mentioned reference circle is constant.

[0067] According to the third method, since the holes are arranged at equal intervals in the radial direction, it is possible to suppress the holes from being densely arranged in the radial direction, and it is possible to suppress the local anisotropy of the distribution of the holes.

[0068] According to the fourth method, a plating apparatus is provided. The plating apparatus includes: a plate of any one of the first method to the third method; and a plating bath for accommodating the above-mentioned plate.

[0069] According to the fifth method, a method for manufacturing a plate that is disposed between a substrate and an anode in a plating bath and has a plurality of circular holes is provided. The method for manufacturing the plate includes: determining the radius of the region for forming a plurality of the above-mentioned holes on the above-mentioned plate, that is, the region radius, the hole diameter of the plurality of the above-mentioned holes, and the target porosity in the above-mentioned region within the above-mentioned region radius; dividing the above-mentioned region into a plurality of annular divided regions having a constant width based on the above-mentioned region radius, the above-mentioned hole diameter, and the above-mentioned target porosity; and forming a plurality of the above-mentioned holes on the reference circles respectively located in the plurality of the above-mentioned divided regions of the above-mentioned plate so that the centers of three of the above-mentioned holes respectively disposed on three adjacent above-mentioned reference circles are not arranged on any radius of the above-mentioned plate.

[0070] According to the fifth method, the centers of three holes respectively disposed on three adjacent reference circles are not arranged on any radius, so it is possible to suppress the holes from being densely arranged on any radius, and thus it is possible to suppress the local anisotropy of the distribution of the holes.

[0071] The gist of the sixth method is that, in the method for manufacturing the plate of the fifth method, the plurality of the above-mentioned divided regions respectively have the same width, and the method for manufacturing the above-mentioned plate further includes: calculating the number of the above-mentioned holes formed in each of the plurality of the above-mentioned divided regions based on the above-mentioned region radius, the above-mentioned hole diameter, and the above-mentioned target porosity.

[0072] The gist of the seventh method is that, in the method for manufacturing the plate of the sixth method, the error between the total area of the plurality of holes in one of the divided regions calculated based on the number of the holes and the total area of the plurality of holes in one of the divided regions calculated based on the target porosity is calculated. When the error is equal to or greater than a specified value, the number of the calculated holes in one of the divided regions is increased and the hole diameter is reduced.

[0073] According to the seventh method, it is possible to make the total hole area calculated based on the number of holes in each divided region closer to the theoretical total hole area calculated based on the target porosity.

[0074] The gist of the eighth method is that, in the method for manufacturing the plate of the sixth method or the seventh method, the reference circles of the plurality of divided regions are located at the centers of the widths of the plurality of divided regions.

[0075] According to the eighth method, since the holes are arranged at equal intervals in the radial direction, it is possible to suppress the holes from being densely arranged in the radial direction and suppress the local anisotropy of the hole distribution.

[0076] The gist of the ninth method is that, in the method for manufacturing the plate of any one of the fifth method to the eighth method, the plurality of holes are arranged at equal intervals in the circumferential direction on the respective reference circles of the plurality of divided regions.

[0077] According to the ninth method, since the plurality of holes are arranged at equal intervals in the circumferential direction on the reference circle, it is possible to suppress the holes from being densely arranged on the reference circle and suppress the local anisotropy of the hole distribution.

Claims

1. A plating device, wherein, it includes: a plate which is disposed between a substrate and an anode in a plating bath, the plate having a plurality of circular holes respectively on three or more reference circles that are concentric and have different diameters, and the centers of three of the holes respectively disposed on three adjacent reference circles not being arranged on any radius of the plate; and a plating bath for accommodating the plate.

2. The plating device according to claim 1, wherein, the plurality of holes are circumferentially and equally spaced on the reference circles.

3. The plating device according to claim 1 or 2, wherein, the difference in diameter between any of the reference circles and an adjacent reference circle is constant.

4. A method for manufacturing a plate which is disposed between a substrate and an anode in a plating bath and the plate has a plurality of circular holes, the method for manufacturing the plate comprises: determining the radius of the region for forming the plurality of holes on the plate, i.e., the region radius, the aperture of the plurality of holes, and the target porosity in the region within the region radius; dividing the region into a plurality of annular divided regions having a constant width based on the region radius, the aperture, and the target porosity; and forming the plurality of holes on the reference circles respectively located in the plurality of divided regions of the plate so that the centers of three of the holes respectively disposed on three adjacent reference circles are not arranged on any radius of the plate, the plurality of divided regions respectively having the same width, the method for manufacturing the plate further comprises: calculating the number of the holes formed in each of the plurality of divided regions based on the region radius, the aperture, and the target porosity.

5. The method for manufacturing a plate according to claim 4, wherein, calculating the error between the total area of the plurality of holes in one of the divided regions calculated based on the number of the holes and the total area of the plurality of holes in one of the divided regions calculated based on the target porosity, when the error is equal to or greater than a specified value, increasing the number of the calculated holes in one of the divided regions and reducing the aperture.

6. The method for manufacturing a plate according to claim 4, wherein, the reference circles of the plurality of divided regions are located at the center of the width of the plurality of divided regions.

7. The method for manufacturing a plate according to any one of claims 4 to 6, wherein, the plurality of holes are circumferentially and equally spaced on the respective reference circles of the plurality of divided regions.

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