TW202300706A - Plating device and plating method capable of achieving the uniformity of the thickness of a plated film - Google Patents

Abstract

A plating device of the present invention is a plating device for plating on a substrate. The plating device includes an anode disposed opposite to the substrate; and an intermediate mask which is disposed on the substrate side between the substrate and the anode, and has an intermediate mask allowing an electric field from the anode the substrate to passes through a first central opening, the inner space of the intermediate mask is provided with an auxiliary anode arranged at the periphery of the first central opening, and the area of the auxiliary anode is 1/5 or less of the area of the anode.

Description

Plating device and plating method

This case is about a plating device and a plating method.

If electrolytic plating is performed on a substrate on which a seed layer is formed, it is known that due to the difference in the resistance value of the current path between the center of the substrate and the edge of the substrate (the resistance value of the seed layer between the center of the substrate and the edge of the substrate), The phenomenon that the thickness of the plating film at the center of the substrate is smaller than that at the edge of the substrate is called a terminal effect. There is one described in US Pat. No. 6,427,316 specification (Patent Document 1) as a plating apparatus that alleviates the terminal effect as described above. In the device described in Patent Document 1, an ion current collimator (corresponding to the anode mask) having an auxiliary electrode is arranged near the anode, and the auxiliary electrode is controlled to function as an anode or a cathode according to the sheet resistance of the substrate. The overall film thickness distribution, and the film thickness distribution at the edge of the substrate is controlled by the stealth sub-electrode (virtual thief cathode) arranged around the substrate. [Prior Technical Literature] [Patent Document]

[Patent Document 1] Specification of US Patent No. 6427316 [Patent Document 2] Japanese Patent Laid-Open No. 2019-56164 [Patent Document 3] US Patent Application Publication No. 2017-0370017 specification

[Problem to be solved by the invention]

If substrates with different substrate specifications such as resist opening ratio and seed layer sheet resistance (hereinafter also referred to as seed resistance) (seed film thickness) are plated in the same plating tank, the influence of terminal effects will vary depending on the substrate specification. , so the optimum opening size of the mask (intermediate mask, anode mask) is different. Therefore, in order to obtain good surface uniformity (in-plane uniformity of coating film thickness), it is necessary to change the opening size of the mask. The number of plating units is reduced and the throughput is reduced.

In an apparatus for plating wafers, there are cases where a mechanical mechanism (mechanical mechanism) that mechanically changes the openings of the intermediate mask and the anode mask is provided, but since the intermediate mask is placed close to the substrate or the stirring bar position, thus limiting the space for setting up the mechanical mechanism. In particular, in a plating apparatus for an angular substrate, since the substrate is larger in size than the wafer, it is difficult to mount a mechanical mechanism. In addition, the intermediate mask is set at a position close to the substrate, so the mechanical mechanism requires high dimensional accuracy, and a precise mechanism is necessary, and the technical threshold is relatively high.

In the device described in Patent Document 1, since the stealth sub-electrode is arranged on the side wall of the plating tank around the substrate, it cannot be used in a plating apparatus that performs plating by standing the substrate vertically. In addition, since the auxiliary electrode provided in the ion current collimator is arranged on the anode side away from the substrate, it is difficult to effectively adjust the plating current at the edge of the substrate. In addition, since the auxiliary electrode is arranged on the anode side away from the substrate, a large current must flow in order to adjust the electric field, and in order to suppress the current density, the area of the auxiliary electrode must be larger than a certain value.

One of the objects of the present invention is to provide a structure for controlling the plating current according to the specifications of the substrate while suppressing the influence of size constraints. [Means to solve the problem]

According to one embodiment, a coating device is provided, which is a coating device used for coating on a substrate, and it is provided with: an anode, which is arranged opposite to the aforementioned substrate; and an intermediate mask, which is placed on the aforementioned substrate Between the anode and the aforementioned substrate side, there is an intermediate mask having a first central opening through which the electric field from the aforementioned anode to the aforementioned substrate passes, and the internal space of the intermediate mask is provided with the first central opening. The surrounding auxiliary anode, the area of the aforementioned auxiliary anode is less than 1/5 of the area of the aforementioned anode.

Embodiments of the present invention will be described below with reference to the drawings. In the attached drawings, the same or similar reference numerals are attached to the same or similar elements, and repeated descriptions of the same or similar elements in the descriptions of the respective embodiments may be omitted. In addition, the features shown in each embodiment can be applied to other embodiments as long as they do not contradict each other.

In this specification, "substrate" refers not only to semiconductor substrates, glass substrates, liquid crystal substrates, and printed circuit substrates, but also includes: magnetic recording media, magnetic recording sensors, mirrors, optical elements, micromechanical elements, or partially manufactured Integrated circuits and other arbitrary objects to be processed. The substrate includes any shape including a polygon and a circle. In addition, expressions such as "front", "rear", "front", "rear", "upper", "lower", "left", "right" are used in this manual, but these are for the convenience of explanation , which represent the positions and directions on the paper of the illustrations, may be different in the actual arrangement such as when the device is in use. (first embodiment)

Fig. 1 is an overall arrangement diagram of a plating apparatus according to an embodiment. The plating apparatus 100 performs a plating process on a substrate while holding the substrate in a substrate holder 11 ( FIG. 2 ). The plating apparatus 100 is roughly divided into: a loading/unloading station 110 for loading or unloading a substrate from the substrate holder 11; a processing station 120 for processing a substrate; and a cleaning station 50a. The processing station 120 includes a pre-processing/post-processing station 120A for performing pre-processing and post-processing of a substrate, and a plating station 120B for performing a plating process on a substrate.

The loading/unloading station 110 has: 1 or a plurality of cassette platforms 25 , and a substrate loading and unloading module 29 . The cassette platform 25 is loaded with the cassette 25a in which the substrate is accommodated. The substrate loading and unloading module 29 is configured to load and detach a substrate from the substrate holder 11 . In addition, a storage 30 for accommodating the substrate holder 11 is provided near (for example, below) the substrate loading and unloading module 29 . The cleaning station 50a has a cleaning module 50 for cleaning and drying the plated substrate. The cleaning module 50 is, for example, a spin dryer.

At a position surrounded by the cassette platform 25, the substrate loading and unloading module 29, and the cleaning station 50a, a transfer robot 27 for transferring substrates between these units is arranged. The transfer robot 27 is configured to be able to travel by a traveling mechanism 28 . The conveying robot 27 is configured such that, for example, the substrate before plating is taken out from the magazine 25a and conveyed to the substrate loading and unloading module 29, and the substrate after plating is picked up by the substrate loading and unloading module 29, and the substrate after plating is conveyed to the washing machine. The cleaning module 50 takes out the cleaned and dried substrates from the cleaning module 50 and stores them in the cassette 25a.

The pre-processing/post-processing station 120A is equipped with a pre-wetting module 32 , a pre-soaking module 33 , a first cleaning module 34 , an air blowing module 35 , and a second cleaning module 36 . The pre-wetting module 32 wets the plated surface of the substrate before the plating process with a treatment liquid such as pure water or deaerated water, thereby replacing the air inside the pattern formed on the substrate surface with the treatment liquid. The pre-wetting module 32 is configured to perform a pre-wetting process in which the plating solution is easily supplied to the inside of the pattern by replacing the processing solution inside the pattern with the plating solution during plating. The prepreg module 33 is configured to perform, for example, an oxide film with high resistance formed on the surface of the seed layer on the surface to be plated of the substrate before the plating process, etch and remove it with a treatment solution such as sulfuric acid or hydrochloric acid, and the plated Pre-dip treatment for cleaning or activating the coated substrate surface. In the first cleaning module 34 , the pre-soaked substrate is cleaned together with the substrate holder 11 with a cleaning solution (pure water or the like). In the air blowing module 35, the substrate after cleaning is drained. In the second cleaning module 36 , the plated substrate is cleaned together with the substrate holder 11 with a cleaning solution. The pre-wet module 32, the prepreg module 33, the first cleaning module 34, the blowing module 35, and the second cleaning module 36 are configured in this order. However, this configuration is an example, and is not limited to the above-mentioned configuration, and other configurations may be adopted for the pre-processing/post-processing station 120A.

The plating station 120B has a plating module 40 which has: a plating tank 39 and an overflow tank 38 . The plating tank 39 is divided into a plurality of plating units. Each plating unit accommodates one substrate inside, and performs plating such as copper plating on the surface of the substrate by immersing the substrate in a plating solution held inside. Here, the type of the plating solution is not particularly limited, as various plating solutions are used according to the application. The configuration of the plating station 120B is an example, and the plating station 120B may have other configurations.

The plating apparatus 100 has, for example, a conveying device 37 of a linear motor type that is positioned on the side of each of these machines and that transports the substrate holder 11 together with the substrate between the machines. The conveying device 37 is configured to have one or a plurality of conveyors, and by one or a plurality of conveyors, it is connected with the substrate loading and unloading module 29, the storage warehouse 30, the pre-wetting module 32, the prepreg module 33, the first The substrate holder 11 is conveyed between the cleaning module 34 , the blowing module 35 , the second cleaning module 36 , and the plating module 40 .

The plating apparatus 100 configured as described above includes a control module (controller) 175 as a control unit configured to control each of the above-mentioned units. The controller 175 has a memory 175B storing a predetermined program, and a CPU 175A that executes the program in the memory 175B. The storage medium constituting the memory 175B stores various setting data, various programs including programs for controlling the plating apparatus 100 , and the like. The program system includes execution of, for example, the transfer control of the transfer robot 27, the loading and unloading control of the substrate to the substrate holder 11 in the substrate loading and unloading module 29, the transfer control of the transfer device 37, the control of the processing in each processing module, and the plating module. The program of the control of the plating process and the control of the cleaning station 50a. Memory media can include non-volatile and/or volatile memory media. As the storage medium, well-known ones such as memory such as computer-readable ROM, RAM, and flash memory, or disk-shaped storage media such as hard disk, CD-ROM, DVD-ROM, or floppy disk can be used.

The controller 175 is configured to be able to communicate with a not-shown host controller that collectively controls the coating device 100 and other related devices, and can exchange data with a database of the host controller. Part or all of the functions of the controller 175 can be implemented by hardware such as ASIC. Part or all of the functions of the controller 175 can also be constituted by a programmer. Part or all of the controller 175 may be disposed inside and/or outside the casing of the coating apparatus 100 . Part or all of the controller 175 can be connected to each part of the plating apparatus 100 by wire and/or wirelessly so as to communicate. (plating module)

FIG. 2 is a schematic diagram showing the coating module 40 . In this figure, one plating unit of the plating tank 39 is shown, and the overflow tank 38 is omitted. However, in the following description, there is a case where one plating unit of the plating tank 39 is referred to as the plating unit 39 . The plating apparatus 100 of the present embodiment is an electrolytic plating apparatus for plating the surface of the substrate W with a metal by passing an electric current through the plating solution Q. The plating module 40 is provided with: a plating tank 39 holding a plating solution inside; an anode (main anode) 60 disposed opposite to the substrate W held in the substrate holder 11 in the plating tank 39; and The intermediate mask 70 adjusts the electric field directed from the anode 60 to the substrate W to adjust the potential distribution on the substrate W. The substrate holder 11 is configured to detachably hold a polygonal (for example, quadrangular) substrate W, and to immerse the substrate W in the plating solution Q in the plating tank 39 . However, in other embodiments, a circular substrate (wafer) may also be used. The anode 60 and the substrate W are arranged to extend in the vertical direction, and are arranged to face each other in the plating solution. The anode 60 is connected to the positive pole of a power supply (not shown) through the anode holder 61 holding the anode 60 , and the substrate W is connected to the negative pole of the power supply through the substrate holder 11 . When a voltage is applied between the anode 60 and the substrate W, a current flows to the substrate W, and a metal film is formed on the surface of the substrate W in the presence of the plating solution.

As the anode 60, an insoluble anode made of, for example, iridium oxide or platinum-coated titanium that is not dissolved in the plating solution is used. However, it is also possible to use a soluble anode as the anode 60 . As for the soluble anode, for example, if copper is plated, a soluble anode made of phosphorus-containing copper can be used. The substrate W is, for example, a semiconductor substrate, a glass substrate, a resin substrate, or any other object to be processed. The metal plated on the surface of the substrate W is, for example, copper (Cu), nickel (Ni), tin (Sn), Sn—Ag alloy, or cobalt (Co). Plating solution Q is an acidic solution containing the metal to be plated, for example, copper sulfate solution if copper is to be plated.

The anode holder 61 is provided with an anode cover 62 that can change the size of the opening 62A. The anode cover 62 adjusts the exposed area of the anode 60 (the effective area that provides the electric field (current) from the anode to the substrate). In the following description, the anode mask 62 is referred to as a variable anode mask (VAM) 62 or VAM62. The anode mask 62 can also be changed, for example, by moving the mask pieces arranged up, down, left, and right to change the size of the opening, or by making a plurality of frames with openings move obliquely relative to each other to change the size of the opening. The size of the opening defined by the overlapping of plural boxes. The variable anode mask as described above is described in, for example, JP-A-2019-56164 (Patent Document 2). Among them, instead of using the variable anode mask 62, a split anode (multi-segment anode) in which the anode is divided into a plurality of anode pieces can be used to select the anode piece through which current flows or adjust the current flowing to each anode piece, thereby adjusting the anode. The effective area or adjust the electric field (current) from the anode towards the substrate. The variable anode mask as described above is described in, for example, US Patent Application Publication No. 2017-0370017 (Patent Document 3).

The anode holder 61 is housed in the anode case 63 . An opening is provided in the anode case 62 at a position facing the anode 60 , and the opening is covered with a diaphragm 64 . The separator 64 is used to oxidize the additive components contained in the plating solution through an electrochemical reaction on the surface of the insoluble anode, and when a decomposition product harmful to the plating performance occurs, it prevents the harmful decomposition product from reaching the substrate surface. However, the electric field (current) from the anode 60 to the substrate W is not hindered by the diaphragm 64 .

The plating module 40 is additionally equipped with a stirring rod 90 for stirring the plating solution. The stirring bar 90 is arranged near the surface of the substrate W of the substrate holder 11 held in the plating tank 39 . The paddle 90 is made of, for example, titanium (Ti) or resin. The stirring bar 90 reciprocates parallel to the surface of the substrate W to agitate the plating solution Q so that metal ions sufficient for plating are uniformly supplied to the surface of the substrate W. As shown in FIG. 2 , the intermediate mask 70 is arranged near the substrate W between the substrate W and the anode 60 , and has a central opening 76 for limiting the electric field in the plating solution.

Fig. 3 is a schematic view of the intermediate mask according to the first embodiment viewed from the substrate side. As shown in FIGS. 2 and 3 , the intermediate cover 70 is provided with: a cover body 71 , an auxiliary anode 80 disposed in the inner space 72 of the cover body 71 , and a shield mounted on the front surface of the cover body 71 . Plate 75. The mask body 71 and the shielding plate 75 are resistant to the plating solution and are made of a material that shields the electric field (current). The mask body 71 has an opening corresponding to the central opening 76 and has a roughly quadrangular shape in front view, and has an internal space 72 for disposing the auxiliary anode 80 . The mask body 71 has an opening on the substrate W side to expose the auxiliary anode 80 , and the shielding plate 75 is attached to the masking body 71 so that the opening 77 of the shielding plate 75 overlaps with the opening. A diaphragm 78 is attached to the opening 77 of the shielding plate 75 , and the auxiliary anode 80 is exposed through the diaphragm 78 . In addition, the mask body 71 is provided with an exhaust passage 73 connected to the internal space 72 , and the upper end of the exhaust passage 73 is an exhaust port 74 opening above the plating liquid surface 91 . In the present embodiment, the exhaust passage 73 and the exhaust port 74 constitute a vent hole.

The auxiliary anode 80 is electrically connected to the bus bar 81 and connected to the positive pole of the power supply (not shown) through the bus bar 81 . The auxiliary anode 80 functions as an auxiliary anode that supplies an electric field (current) to the substrate W by applying a positive bias voltage from a power source. Auxiliary anode 80 is formed of insoluble anode material. The exhaust passage 73 exhausts oxygen generated by the electrode reaction in the auxiliary anode 80 to the outside of the tank. This prevents air bubbles due to oxygen from accumulating around the auxiliary anode 80 to hinder the electric field (current) applied to the substrate W by the auxiliary anode 80 . Wherein, if the auxiliary anode 80 is formed of a soluble anode material, the exhaust passage 73 may be omitted.

In this embodiment, auxiliary anodes 80 are provided along the sides of the central opening 76 , and auxiliary anodes 80 are not provided at positions corresponding to corners of the central opening 76 . Thereby, it is possible to prevent the electric field (current) from concentrating on the corner portion of the substrate W and causing the film thickness to become non-uniform in this portion. Wherein, according to the specifications of the substrate, auxiliary anodes may also be provided at the corners of the central opening 76, or the auxiliary anodes may also be formed as an integral ring-shaped member.

The auxiliary anode 80 is arranged on the intermediate mask 70 arranged near the substrate W for the purpose of uniformizing the thickness distribution of the plating film near the edge of the substrate. Therefore, compared with the case where the auxiliary anode is arranged on the anode 60 side, it can be formed for a small area. In one example, the total area of the auxiliary anode 80 is not more than 1/5 of the area of the anode. Wherein, as shown in FIG. 2, if the distance between the intermediate mask 70 and the substrate W is set as D1, and the distance between the anode 60 and the substrate W is set as D2, in one example, the distance between the intermediate mask 70 and the substrate W is The distance D1 between W is not less than 1/4 and not more than 1/3 of the distance D2 between the anode 60 and the substrate W. The distance D1 between the intermediate mask 70 and the substrate W is the distance between the anode-side surface of the intermediate mask 70 and the plated surface of the substrate W. As shown in FIG. In addition, the distance D2 between the anode 60 and the substrate W is defined as the distance between the surface of the anode 60 on the substrate side and the plated surface of the substrate W. Wherein, FIG. 2 is a schematic diagram for explaining the structure, and it should be noted that it does not necessarily correspond to the actual size.

The shield plate 75 is mounted on the front surface of the shield body 71 . The shielding plate 75 has a central opening 76 smaller than the central opening of the shield body 71 , and the central opening 76 of the shielding plate 75 is configured to define the central opening 76 of the intermediate shield 70 . By adjusting the size of the central opening 76 of the shielding plate 75 , the size of the central opening 76 of the intermediate mask 70 can be adjusted, and the electric field (current) from the anode 60 to the substrate W can be adjusted. As shown in FIGS. 2 and 3 , the shielding plate 75 has an opening 77 exposing the auxiliary anode 80 on each side, and the opening 77 is covered by a diaphragm 78 . Separator 78 is used to prevent the harmful decomposition products from reaching the surface of the substrate if the additive components contained in the plating solution are oxidized by the electrochemical reaction on the surface of the insoluble anode, and if a decomposition product harmful to the plating performance occurs. However, the electric field (current) to the substrate W from the auxiliary anode 80 is not hindered by the diaphragm 78 . By adjusting the size of the opening 77 of the shielding plate 75 , the electric field (current) applied to the substrate W by the auxiliary anode 80 can be adjusted.

In this embodiment, the size of the central opening 76 of the intermediate mask 70 (shielding plate 75 ) is selected in accordance with the situation where the terminal effect is large (small resist aperture ratio, large seed resistance/small seed film thickness). That is, in accordance with the fact that the terminal effect is large and the current flowing to the edge of the substrate is higher than that at the center of the substrate, the shielding plate 75 is designed so that the current flowing to the edge of the substrate is reduced and the thickness of the plating film becomes uniform. The size of the central opening 76 is reduced. Next, according to the size of the terminal effect of the substrate W (resist opening ratio, seed resistance), the plating current supplied from the auxiliary anode 80 to the substrate W (mainly the edge of the substrate) is adjusted, thereby achieving and changing (increasing) The same effect as the opening size of the intermediate mask 70 is used to uniformize the thickness distribution of the plated film on the substrate. Since the auxiliary anode 80 is disposed near the edge of the substrate, adjustment of the plating current to the edge of the substrate is particularly effective.

In addition, according to this embodiment, the size of the opening 77 of the auxiliary anode 80 of the shielding plate 75 is adjusted and/or the shielding plate 75 is adjusted according to the specification range (resist aperture ratio, seed film thickness) of the substrate W to be plated. The size of the central opening 76 can be finely adjusted to correspond to the range of terminal effects.

However, the shielding plate 75 may not be provided, and a diaphragm may be provided at the opening of the auxiliary anode 80 exposing the shield body 71 . At this time, the central opening of the mask body 71 becomes the central opening of the intermediate mask 70 . By adjusting the size of the opening of the auxiliary anode 80 exposing the mask body 71 and/or adjusting the size of the central opening of the mask body 71 , the range of the corresponding terminal effect can be fine-tuned.

FIG. 4 is an explanatory diagram showing the electric field applied by the anode 60 to the substrate W when the terminal effect is large (small resist aperture ratio, large seed resistance/small seed film thickness). FIG. 5 is an explanatory diagram showing the electric field applied by the anode 60 to the substrate W when the terminal effect is small (large resist aperture ratio, small seed resistance/large seed film thickness). FIG. 6 is an explanatory diagram illustrating a method of adjusting the thickness distribution of a plated film. However, in FIGS. 4 and 5 , a part of the shielding plate 75 is omitted and shown. In this embodiment, the thickness distribution of the plating film is adjusted by adjusting the opening size of the variable anode mask (VAM) 62 and the current flowing to the auxiliary anode 80 . Before adjustment, it is assumed that the opening size of the variable anode cover 62 is the middle size (the first size), and the current of the auxiliary anode 80 is zero. The graphs in each column in Figure 6 show the thickness distribution of the plated film on the substrate. The horizontal axis represents the position on the substrate (the linear position passing through the center of the substrate). The farther it is, the closer it is to the edge of the substrate. The vertical axis of the graph in each column represents the thickness of the plating film on the substrate. Wherein, if the variable anode cover 62 is replaced by a split anode, it is controlled to select the anode piece through which the current flows or adjust the flow to each Anode current.

As shown in the first layer of the table in Figure 6, if the terminal effect is large, before the adjustment of the variable anode mask and the auxiliary anode, the influence of the terminal effect will appear on the distribution of the coating film thickness, and the coating film thickness at the center of the substrate becomes smaller, and the thickness of the plating film at the edge of the substrate becomes larger. At this time, as shown in FIG. 4, if the size of the opening 62A of the variable anode cover 62 is adjusted to a second size smaller than the middle size according to the size of the terminal effect, the "VAM" in the first layer of the table in FIG. 6 In the graph of the column of "Optimization of opening", the thickness distribution of the plating film is uniformized as shown by the solid line. Wherein, the current of the auxiliary anode 80 is kept at zero. This is based on the fact that the size of the central opening 76 of the intermediate mask 70 of this embodiment is optimized in accordance with the situation where the terminal effect is large. Wherein, if a split anode is used to replace the variable anode cover 62, the anode piece through which the current flows is selected in such a manner that the electric field corresponding to the opening 62A of the variable anode cover 62 is the second size (<the first size) Or adjust the current flowing to each anode piece, thereby controlling to reduce the effective area of the anode or reduce the expansion of the electric field (current) from the anode toward the substrate.

As shown in the second layer of the table in FIG. 6 , if the terminal effect is moderate, before the adjustment of the variable anode mask and the auxiliary anode, the thickness of the coating film at the edge of the substrate is smaller than the thickness of the coating film at the center of the substrate. This is based on the fact that the size of the central opening 76 of the intermediate mask 70 of the present embodiment is optimized in accordance with the case where the terminal effect is large. In other words, if the terminal effect is moderate, the current flowing to the center of the substrate in the configuration before adjustment exceeds the plating current flowing to the edge of the substrate when the terminal effect is large. At this time, when a moderate current (first current) flows through the auxiliary anode 80 according to the magnitude of the terminal effect, an electric field (current) is supplied from the auxiliary anode 80 to the edge of the substrate, and the thickness of the plating film on the edge of the substrate increases. , and as shown by the solid line in the column of "auxiliary anode current optimization" in the second layer of the table in Fig. 6, the plating film thickness is uniformized. At this time, the opening size of the variable anode shield 62 may be formed to keep the middle size as it is. Wherein, if a split anode is used instead of the variable anode cover 62, it can be formed to be the same as before selecting the anode piece through which current flows or adjusting the current flowing to each anode piece.

As shown in the third layer of the table in Figure 6, if the terminal effect is small, before the adjustment of the variable anode mask and the auxiliary anode, the thickness of the coating film at the edge of the substrate is smaller than the thickness of the coating film at the center of the substrate. powerful. At this time, as shown in FIG. 5, if the size of the opening 62A of the variable anode cover 62 is adjusted to a size (third size) larger than the middle size (first size) according to the size of the terminal effect, as shown in FIG. The column of "VAM opening optimization" in the third layer of Table 6 is shown by a solid line. The difference in the electric field (current) reaching the center of the substrate and the edge is reduced, and the plated film at the center and edge of the substrate is reduced. Difference of thickness is reduced. In addition, when the second current larger than the first current flows through the auxiliary anode 80 according to the magnitude of the terminal effect, as shown in FIG. In the column of "auxiliary anode current optimization" in the third layer of the table in FIG. 6, as shown by the solid line, the plating film thickness is uniformized. Wherein, if a split anode is used to replace the variable anode cover 62, the anode piece through which the current flows is selected in such a way that the electric field corresponding to the opening 62A of the variable anode cover 62 is the third size (>the first size) Or adjust the current flowing to each anode sheet, thereby controlling to increase the effective area of the anode or increase the expansion of the electric field (current) from the anode to the substrate.

As described above, in this embodiment, the size of the opening 62A of the variable anode cover 62 and the current of the auxiliary anode 80 are adjusted according to the size of the terminal effect, thereby uniformizing the thickness distribution of the plating film. . More specifically, the larger the terminal effect, the smaller the size of the opening 62A of the variable anode cover 62 and the smaller the current of the auxiliary anode 80 according to the size of the terminal effect, and the smaller the terminal effect, according to the size of the terminal effect The size of the opening 62A of the variable anode cover 62 is adjusted to be larger and the current of the auxiliary anode 80 is larger, so that the thickness distribution of the coating film can be uniformed.

The adjustment of the above-mentioned VAM opening and the adjustment of the auxiliary anode current can be carried out before the substrate is plated according to the size of the terminal effect. In addition, during substrate plating, the adjustment of the opening of the variable anode mask and the adjustment of the auxiliary anode current can also be implemented according to the size of the terminal effect changing with the growth of the plating film thickness.

Through the above embodiment, as shown in FIGS. 4 and 5 , the current supplied to the auxiliary anode 80 can be adjusted to achieve the same effect as the adjustment of the opening size of the central opening 76 of the intermediate cover 70 (the adjustment of the opening size of the intermediate cover 70 can be achieved). Substantial opening size (effective opening area)). Therefore, there is no need for a mechanical mechanism for adjusting the opening size of the intermediate mask, and it can be adjusted so that the thickness distribution of the plating film becomes uniform according to the substrate specifications (resist opening ratio, seed film thickness). The intermediate cover 70 is disposed at a position close to the substrate W and the paddle 90, so the space for installing a mechanical mechanism for adjusting the opening size is limited. The adjusted auxiliary anode 80 can arrange the electric field adjusting device in a narrow space. In particular, in the coating apparatus for square substrates, since the size of the substrate becomes larger, high dimensional accuracy and precise mechanisms are required for the mechanical mechanism, and the technical threshold is high. However, according to this embodiment, since the mechanical mechanism is not required, it can be Arrange the electric field adjustment device in a narrow space.

In addition, according to the above embodiment, the maintenance of the intermediate cover 70 is easy, and the management of the liquid in the intermediate cover 70 is also easy. If the auxiliary cathode is used, in order to prevent precipitation of the auxiliary cathode, the auxiliary cathode is separated by an ion exchange membrane, and it is necessary to fill it with an electrolyte solution that does not contain the plating metal different from the plating solution, and the liquid management/structure is more complicated. On the other hand, in this embodiment, since the auxiliary anode is used, there is no plating deposition on the auxiliary anode, and liquid management is easy. In addition, if the insoluble anode is used as the auxiliary anode, there is no consumption of the auxiliary anode, and the maintenance is relatively easy.

In addition, according to the above-mentioned embodiment, since the auxiliary anode is provided in the intermediate mask, it is less subject to size constraints compared with the case where the electrode is arranged between the substrate and the paddle. In addition, since the auxiliary anode is arranged inside the intermediate cover, it is not necessary to separately provide a structure for supporting the auxiliary anode, and the complexity of the configuration can be suppressed. (Second Embodiment)

Fig. 7 is a schematic view of the intermediate mask according to the second embodiment viewed from the substrate side. Fig. 8 is a cross-sectional view of each part of the intermediate mask according to the second embodiment. The cross-sectional views in Fig. 8 are cross-sectional views along the lines A-A', B-B', and C-C' in Fig. 7 . In the following description, the same reference numerals will be assigned to the same members as those of the above-mentioned embodiment, detailed description will be omitted, and differences from the above-mentioned embodiment will be mainly described.

In the intermediate mask 70 of this embodiment, as shown in FIG. 7 , in a front view, the outlet 71H of the electric field (current) from the auxiliary anode 80 is not provided at a position overlapping with the auxiliary anode 80 , but is provided at A different location than the auxiliary anode 80 (more inside the middle shroud). The middle cover 70 is provided with: a base panel 71A, a rear cover 71B, a front cover 71C, a central block 71E, and a corner block 71D constituting a cover body. The corner block 71D is provided for adjusting the opening size or opening shape of the corner portion of the central opening 76 of the mask, but it can also be omitted. All or a part of the base panel 71A, the rear cover 71B, the front cover 71C, the central block 71E, and the corner block 71D may be integrally formed. All or part of the base panel 71A, the front cover 71C, and the central block 71E may be integrally formed. For example, the base panel 71A and the front cover 71C may be integrally formed, the front cover 71C and the central block 71E may be integrally formed, or the base panel 71A, the front cover 71C, and the central block 71E may be integrally formed.

As shown in FIG. 8 , an internal space 72 is provided between the base panel 71A and the rear cover 71B, and an auxiliary anode 80 is provided in the internal space 72 . The auxiliary anode 80 is electrically connected to the bus bar 81 in the internal space 72 , and a power supply (not shown) supplies current to the auxiliary anode 80 through the bus bar 81 . In addition, between the base panel 71A and the rear cover 71B, an exhaust passage 73 connected to the internal space 72 is provided, and the upper end of the exhaust passage 73 is formed as an exhaust passage opening above the liquid surface 91 of the plating solution. Mouth 74. An opening for exposing the auxiliary anode 80 is provided on the front surface of the base panel 71A, and the opening is covered with a diaphragm 78 .

The front cover 71C is attached to the front surface of the base panel 71A. As shown in the B-B' sectional view of FIG. 8 , the front cover 71C is provided with a passage 71F connected to an opening of the base panel 71A where the auxiliary anode 80 is exposed. The base panel 71A and the front cover 71C have a central opening corresponding to the central opening 76 ( FIG. 7 ) of the middle cover 70 . In this central opening, corner blocks 71D and center blocks 71E are attached to the base panel 71A and the front cover 71C. The corner block 71D and the central block 71E may also be fixed to each other. The central opening 76 of the middle mask 70 is defined inside the corner block 71D and the central block 71E. A passage 71G connected to the passage 71F of the front cover 71C is provided in the central block 71E, and an end portion of the passage 71G is formed as an outlet 71H. Therefore, the electric field (current) from the auxiliary anode 80 is supplied to the substrate W through the passage 71F of the front cover 71C, and the passage 71G and the outlet 71H of the central block 71E.

According to this embodiment, the same operational effects as those of the first embodiment are achieved, and the following operational effects are also achieved. According to this embodiment, by adjusting the opening position and/or opening size of the outlet 71H of the central block 71 , the controllable range obtained by the auxiliary anode 80 can be adjusted. In addition, according to this embodiment, when plating on a substrate with a small terminal effect, the extraction position of the electric field (current) (leading port 71H ), so that the area can be effectively thickened by the current from the auxiliary anode, and the thickness distribution of the plated film on the entire substrate can be more uniform. (Other implementation forms)

(1) In the above-mentioned embodiment, the case of plating on an angular substrate was described as an example, but the above-mentioned embodiment is also applicable to the case of plating on a circular substrate (wafer, etc.). (2) In the above embodiment, the case where an insoluble anode is used as an auxiliary anode is described, but a soluble anode may also be used. In this case, the separator separating the auxiliary anode and the exhaust passage for exhausting oxygen generated in the auxiliary anode can be omitted. (3) In the above-mentioned embodiment, a so-called immersion type plating device in which the substrate is immersed in the plating solution in the vertical direction is described, but a so-called face-down type ( cup type) coating module applicable to the above-mentioned embodiment.

The present invention can also be described in the following aspects. According to form 1, a coating device is provided, which is a coating device used for coating on a substrate, and it is equipped with: an anode, which is arranged opposite to the aforementioned substrate; and an intermediate mask, which is connected between the aforementioned substrate and the substrate. The anodes are arranged on the side of the substrate, and there is an intermediate mask with a first central opening through which the electric field from the anode to the substrate passes, and an internal space of the intermediate mask is arranged at the first central opening. For the surrounding auxiliary anodes, the area of the auxiliary anode is not more than 1/5 of the area of the anode. The intermediate mask is also called a tunnel regulating plate (TRP), and is a mask that adjusts the passage of an electric field (current) from the anode to the substrate in the vicinity of the substrate. Unlike the ion current collimator arranged on the anode side, the intermediate mask is arranged between the substrate and the anode on the substrate side, in other words, near the substrate.

With this aspect, adjusting the current supplied to the auxiliary anode arranged in the intermediate cover can achieve the same effect as changing the opening size of the intermediate cover, so a mechanical mechanism for adjusting the opening size of the intermediate cover is not required , can suppress the influence of the terminal effect due to the substrate specification (resist opening ratio, seed film thickness), and adjust the plating film thickness distribution to become uniform. The intermediate mask is placed close to the substrate (and the paddle), so the space for installing the mechanical mechanism to adjust the opening size is limited. However, according to this embodiment, the auxiliary anode that can electrically adjust the actual opening size of the intermediate mask can be used. , disposing the electric field adjustment device in a narrow space. Here, the opening size of the intermediate mask in consideration of the effect of the electric field (current) supplied to the substrate from the auxiliary anode is referred to as a substantial opening size (effective opening size). In one example, the size of the first central opening of the middle mask is reduced (to a smaller size) in accordance with the situation that the terminal effect is larger. Next, adjust the current supplied to the auxiliary anode according to the terminal effect of the substrate (resist opening ratio, seed film thickness), so as to achieve the same effect as changing the opening size of the intermediate mask, and the film at the edge of the substrate can be Uniform thickness.

In addition, since the auxiliary anode is arranged on the intermediate mask arranged near the substrate, the electric field to the edge of the substrate can be effectively controlled by the auxiliary anode with a small area (less than 1/5 of the area of the anode), and the terminal due to The impact caused by the effect. In addition, since the auxiliary anode is arranged near the edge of the substrate where electric field control is required, compared with the case where the auxiliary anode is arranged farther from the edge of the substrate, the auxiliary anode with a smaller area can flow a small current. And effectively control the electric field to the edge of the substrate. Among them, if a large current is passed through the auxiliary anode with a small area, there are disadvantages as shown below. If a soluble auxiliary anode (phosphorus-containing copper) is used, the formation of black film on the surface of the auxiliary anode becomes unstable, thereby increasing the occurrence of residue or anode sludge from the auxiliary anode, which may affect the quality of the plating film. In the case of an insoluble anode, the potential of the electrode during plating becomes too high, and side reactions such as oxidation of Cl ⁻ ions in the plating solution may occur.

According to form 2, a coating device is provided, which is a coating device for coating on a substrate, and it is provided with: an anode, which is arranged opposite to the aforementioned substrate; and an intermediate mask, which is arranged on the aforementioned substrate Between the aforementioned anode, there is an intermediate mask with a first central opening through which the electric field from the aforementioned anode to the aforementioned substrate passes, and an auxiliary anode arranged around the first central opening is provided in the inner space of the intermediate mask, The intermediate mask has a vent hole which communicates with the internal space and forms an opening above the liquid surface of the plating solution.

With this aspect, the gas generated in the inner space of the intermediate cover can be exhausted to the outside. For example, if the auxiliary anode is insoluble, the oxygen generated by the electrode reaction in the auxiliary anode can be discharged from the inner space of the intermediate cover to the outside of the intermediate cover. Thereby, it is possible to prevent or suppress the accumulation of air bubbles around the auxiliary anode to hinder the electric field (current) from the auxiliary anode to the substrate.

According to aspect 3, in the plating apparatus of aspect 1 or 2, the distance between the intermediate mask and the substrate is not less than 1/4 and not more than 1/3 of the distance between the anode and the substrate.

With this aspect, the auxiliary anode disposed on the intermediate mask can be arranged very close to the edge of the substrate, and the electric field (current) from the auxiliary anode to the edge of the substrate can be efficiently controlled. Thereby, terminal effects can be efficiently controlled.

According to form 4, in any one of the coating devices of forms 1 to 3, the aforementioned intermediate mask has: a mask body having a second central opening, and having the aforementioned internal space around the second central opening , the aforementioned substrate side of the aforementioned inner space is opened; and a shielding plate, which is a shielding plate set to cover the aforementioned inner space of the aforementioned shielding body, and has a third central opening smaller than the aforementioned second central opening, and the aforementioned third central The opening defines the first central opening, and has a first opening overlapping at least a part of the auxiliary anode.

With this aspect, by adjusting the size of the third central opening of the shielding plate, the electric field (current) from the anode to the substrate can be adjusted. In addition, by adjusting the size of the first opening of the shielding plate, the intensity of the electric field from the auxiliary anode to the substrate can be adjusted.

According to the aspect 5, in the coating apparatus of the aspect 4, the said shielding plate has the diaphragm which covers the said 1st opening separately.

With this form, if the auxiliary anode is insoluble, the additive components contained in the plating solution are oxidized due to the electrochemical reaction on the surface of the insoluble auxiliary anode, and if decomposition products harmful to the plating performance are generated, harmful decomposition can be suppressed. The product reaches the surface of the substrate, and the plating performance can be maintained.

According to aspect 6, in any one of the plating devices of aspects 1 to 3, the above-mentioned intermediate mask has a passage through which the electric field from the aforementioned auxiliary anode to the aforementioned substrate passes, and in a plane parallel to the aforementioned substrate, the aforementioned passage The outlet is located at a position that does not overlap with the aforementioned auxiliary anode. For example, the outlet of the passage is in a plane parallel to the substrate, and may be provided inside the auxiliary anode.

With this form, when plating on a substrate with a small terminal effect, the extraction of the electric field (current) from the intermediate mask is set according to the specific area where the thickness of the plating film is particularly reduced (changed according to the specification of the substrate or the method of power supply). The position is also the exit of the passage, whereby the specific area is effectively thickened by the current from the auxiliary anode, and the thickness distribution of the plating film can be more uniform.

According to form 7, in the coating device of form 6, the aforementioned intermediate mask system has: a mask body; a cover member, which is installed to cover the aforementioned substrate side of the aforementioned mask body, together with the aforementioned mask body to form a corresponding The 4th central opening of the aforementioned 1st central opening; and the block, which installs the aforementioned mask body and the aforementioned cover on the edge of the aforementioned 4th central opening, the aforementioned mask body system has the aforementioned internal space, and has the same The second opening where at least a part of the auxiliary anode overlaps, the cover has a first passage communicating with the second opening, the block has a second passage communicating with the first passage, the first passage and The second via forms the via through which an electric field from the auxiliary anode toward the substrate passes.

With this aspect, a passage for passing an electric field (current) from the auxiliary anode to the outlet away from the auxiliary anode can be formed with a simple configuration by covering the main body, the lid, and the block.

According to aspect 8, in the plating apparatus of aspect 7, the said mask main body system has the diaphragm which covers the said 2nd opening separately.

With this aspect, the internal space where the auxiliary anode is arranged can be isolated by the diaphragm. Through the electrochemical reaction on the surface of the insoluble auxiliary anode, the additive components contained in the plating solution are oxidized. If the decomposition products harmful to the plating performance occur, the harmful decomposition products can be prevented from reaching the substrate surface by the diaphragm. And the plating performance can be maintained.

According to form 9, in any one of the coating devices of forms 1 to 8, the aforementioned substrate is quadrangular, the aforementioned first central opening of the aforementioned intermediate mask has a shape corresponding to the shape of the aforementioned substrate, and the aforementioned auxiliary anode is along the aforementioned The four sides of the first central opening are arranged.

With this form, the above-mentioned effects can be achieved on a quadrangular substrate. In the coating apparatus for angular substrates, the size of the substrate is larger than that of the wafer, so it is difficult to install a mechanical mechanism for adjusting the size of the mask opening. In addition, the intermediate mask is installed close to the substrate, so the change of the opening size has a great influence on the thickness of the plating film, and high dimensional accuracy is required for the mechanical mechanism, so a precise mechanism is necessary. According to this embodiment, in the coating device for large-sized angular substrates, a mechanical mechanism with a high technical threshold is not required, and the opening size of the intermediate mask can be changed by controlling the current flowing to the auxiliary anode. Effect.

According to aspect 10, in the coating apparatus of aspect 9, the auxiliary anode is divided into a plurality of auxiliary anodes, and the auxiliary anodes are arranged along each side of the first opening except the corner of the first opening.

According to this form, when the electric field concentrates on the corners of the quadrangular substrate and the film thickness becomes large, the increase of the film thickness at the corners can be suppressed.

According to the aspect 11, in any one of the coating devices of the aspects 1 to 10, a variable anode mask for adjusting the exposed area of the anode is additionally provided.

With this form, the exposed area of the anode (the effective area that provides the electric field toward the substrate) can be adjusted by changing the anode mask according to the size of the terminal effect. In this way, according to the size of the terminal effect, the control of the current flowing to the auxiliary anode of the intermediate mask and the control of the electric field from the anode to the substrate can be combined to adjust the magnitude of the plating current flowing to each part of the substrate to achieve plating Uniform film thickness.

According to Form 12, in any one of Forms 1 to 10, the anode is divided into a plurality of split anodes, and by selecting the anode plate through which current flows, the anode that provides the electric field toward the substrate is adjusted. The effective area, or the current flowing to each anode sheet is adjusted, thereby adjusting the electric field from the anode to the substrate.

With this form, the electric field from the anode to the substrate can be electrically controlled according to the magnitude of the terminal effect. In this way, according to the size of the terminal effect, the control of the current flowing to the auxiliary anode of the intermediate mask and the control of the electric field from the anode to the substrate can be combined to adjust the magnitude of the plating current flowing to each part of the substrate, and achieve plating. Uniform coating thickness.

By aspect 13, there is provided a method, which is a method of coating a substrate, comprising: preparing an intermediate mask disposed between the substrate and the anode, the intermediate mask having: controlling an electric field from the anode toward the substrate and an auxiliary anode arranged around the central opening with an area less than 1/5 of the area of the aforementioned anode; and adjusting the direction from the aforementioned anode to the aforementioned The electric field of the substrate is extended, and the electric current supplied to the auxiliary anode arranged on the intermediate mask is adjusted.

According to aspect 14, in the method of aspect 13, the expansion of the electric field from the anode toward the substrate is adjusted by a variable anode mask that adjusts the exposed area of the anode.

According to form 15, in the method of form 13, the aforementioned anode is divided into a plurality of split anodes, and the orientation of the anode from the aforementioned anode is adjusted by selecting the anode plate through which current flows or by adjusting the current flowing to each anode plate. Expansion of the electric field of the aforementioned substrate.

The embodiments of the present invention have been described above, but the above-mentioned embodiments of the invention are intended to facilitate the 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 the gist, and it goes without saying that the present invention includes their equivalents. In addition, any combination of the embodiments and modified examples is possible within a range in which at least a part of the above-mentioned problems can be solved, or at least a part of the effects can be achieved, and any combination of the constituent elements described in the claims and the specification is possible. combined, or omitted.

11: Substrate holder 25: Box platform 25a: Box 27:Transfer robot 28: Walking mechanism 29: Substrate loading and unloading module 30: Repository 32: Pre-wet module 33: Prepreg module 34: The first cleaning module 35: Blowing module 36: The second cleaning module 38: overflow tank 39: Plating tank (plating unit) 40: Plating module 50: Cleaning module 50a: washing station 60: anode 61: Anode holder 62: Anode mask 62A: Opening 63: anode box 64: Diaphragm 70: Intermediate mask 71: mask body 71A: Base panel 71B: Back cover 71C: front cover 71D: Corner block 71E: Central block 71F: Passage 71G: Access 71H: export port 72: Internal space 73: exhaust passage 74: Exhaust port 75: shielding board 76: central opening 77: opening 78: Diaphragm 80: auxiliary anode 81: bus bar 90: stir stick 91: liquid surface 100: Plating device 110: Loading/unloading station 120: processing station 120A: Pre-processing/post-processing station 120B: Plating station 175:Control module (controller) 175A:CPU 175B: memory D1, D2: distance Q: Plating solution W: Substrate

Fig. 1 is an overall arrangement diagram of a plating apparatus according to an embodiment. Figure 2 shows a schematic diagram of the plating module. Fig. 3 is a schematic view of the intermediate mask according to the first embodiment viewed from the substrate side. Fig. 4 is an explanatory diagram showing the electric field from the anode to the substrate when the terminal effect is large. Fig. 5 is an explanatory diagram showing the electric field from the anode to the substrate when the terminal effect is small. FIG. 6 is an explanatory diagram illustrating a method of adjusting the thickness distribution of a plated film. Fig. 7 is a schematic view of the intermediate mask according to the second embodiment viewed from the substrate side. Fig. 8 is a cross-sectional view of each part of the intermediate mask according to the second embodiment.

11: Substrate holder

39: Plating tank (plating unit)

40: Plating module

60: anode

61: Anode holder

62: Anode mask

62A: Opening

63: anode box

64: Diaphragm

70: Intermediate mask

71: mask body

72: Internal space

73: exhaust passage

74: Exhaust port

75: shielding board

76: central opening

77: opening

78: Diaphragm

80: auxiliary anode

81: bus bar

90: stir stick

91: liquid level

D1, D2: distance

Q: Plating solution

Claims (15)

A plating device is used for plating on a substrate, which has: an anode disposed opposite to the aforementioned substrate; and An intermediate mask, which is arranged on the side of the substrate between the aforementioned substrate and the aforementioned anode, has an intermediate mask with a first central opening through which the electric field from the aforementioned anode to the aforementioned substrate passes, and the inner space of the intermediate mask having an auxiliary anode disposed around the aforementioned first central opening, The area of the auxiliary anode is not more than 1/5 of the area of the anode. A plating device is used for plating on a substrate, which has: an anode disposed opposite to the aforementioned substrate; and The intermediate mask is arranged between the aforementioned substrate and the aforementioned anode, and has a first central opening through which the electric field from the aforementioned anode to the aforementioned substrate passes. Auxiliary anode around the first central opening, The intermediate mask has a vent hole which communicates with the internal space and forms an opening above the liquid surface of the plating solution. The coating device according to claim 1 or 2, wherein the distance between the intermediate mask and the substrate is not less than 1/4 and not more than 1/3 of the distance between the anode and the substrate. As the coating device of claim 1 or 2, wherein the aforementioned intermediate shield has: a mask body having a second central opening and the internal space around the second central opening, and the internal space is opened on the substrate side; and A shielding plate, which is set to cover the aforementioned internal space of the aforementioned shielding body, and has a third central opening smaller than the aforementioned second central opening, the aforementioned third central opening defines the aforementioned first central opening, and the shielding plate has the same shape as the aforementioned The first opening in which at least a part of the auxiliary anode overlaps. The coating device according to claim 4, wherein the shielding plate additionally has a diaphragm covering the first opening. The coating device according to claim 1 or 2, wherein the intermediate mask has a passage for the electric field from the auxiliary anode to the substrate to pass through, and the outlet of the passage is located in a plane parallel to the substrate. The position where the aforementioned auxiliary anodes do not overlap. As the coating device of claim 6, wherein the aforementioned intermediate shield has: mask body; a cover member installed to cover the substrate side of the mask body, together with the mask body forming a fourth central opening corresponding to the first central opening; and a block, which is to install the aforementioned mask body and the aforementioned cover on the edge of the aforementioned fourth central opening, The aforementioned mask system has the aforementioned internal space, and has a second opening overlapping at least a part of the aforementioned auxiliary anode, the aforementioned cover has a first passage communicating with the aforementioned second opening, and the aforementioned block has a second opening that communicates with the aforementioned first opening. A second path in which the path communicates, the first path and the second path form the path through which an electric field from the auxiliary anode toward the substrate passes. The coating device according to claim 7, wherein the mask main body additionally has a diaphragm covering the second opening. The coating device according to claim 1 or 2, wherein the substrate is quadrangular, the first central opening of the intermediate mask has a shape corresponding to the shape of the substrate, and the auxiliary anode is along the opening of the first central opening. Four sides for configuration. Such as the coating device of claim 9, wherein the aforementioned auxiliary anode is divided into a plurality of auxiliary anodes, The auxiliary anode is arranged along each side of the first opening except a corner portion of the first opening. The coating device according to claim 1 or 2, wherein a variable anode mask for adjusting the exposed area of the anode is additionally provided. The coating device as claimed in claim 1 or 2, wherein the aforementioned anode is a divided anode divided into a plurality of anode sheets, By selecting the anode piece through which current flows, the effective area of the anode that provides the electric field toward the substrate is adjusted, or the current flowing to each anode piece is adjusted, thereby adjusting the electric field from the anode toward the substrate. A plating method for plating a substrate comprising: An intermediate mask disposed between the substrate and the anode is prepared, and the intermediate mask has: a central opening for controlling an electric field from the anode toward the substrate; Auxiliary anodes with an area of less than 5; and According to the resist opening ratio of the substrate and the size of the seed resistance, the expansion of the electric field from the anode to the substrate is adjusted, and the current supplied to the auxiliary anode disposed on the intermediate mask is adjusted. The plating method according to claim 13, wherein the expansion of the electric field from the anode to the substrate is adjusted by adjusting the variable anode mask which adjusts the exposed area of the anode. The plating method of claim 13, wherein the aforementioned anode is a split anode that is divided into a plurality of anode sheets, The spread of the electric field from the anode toward the substrate is adjusted by selecting the anode piece through which the current flows, or by adjusting the current flowing to each anode piece.

Images