Substrate liquid processing apparatus and substrate liquid processing method

Abstract

According to the present invention, a control unit outputs control signals so as to control a plating-solution supply unit and an energizing unit and thus perform a first electrolytic plating treatment by electrifying a treatment surface while a plating solution is in contact with a first facing area, which is a portion of an electrode facing surface, and outputs control signals so as to control the plating-solution supply unit and the energizing unit and thus perform, after the first electrolytic plating treatment, a second electrolytic plating treatment by electrifying the treatment surface while the plating solution is in contact with a second facing area of the electrode facing surface, said second facing area being larger than the first facing area.

Description

[Technical field]

[0001] The present disclosure relates to a substrate liquid processing apparatus and a substrate liquid processing method. [Background technology]

[0002] Electrolytic plating (electrical plating) is used to embed metal wiring in minute recesses (trench, etc.) of a semiconductor substrate. Patent Document 1 discloses a single-wafer substrate processing apparatus that manufactures copper wiring substrates using electrolytic plating. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-133160 A Summary of the Invention

[0004] In electrolytic plating, a plating metal is deposited on a seed layer of a substrate (wafer) by passing electricity through the substrate. More specifically, a plating metal is deposited over the entire processing surface of the substrate by passing electricity through an electrode connected to the outer periphery of the substrate.

[0005] When electricity is applied to the substrate in this manner, a voltage drop occurs in the substrate due to the electrical resistance of the seed layer. The degree of this voltage drop increases with distance from the electrode connection portion (i.e., the outer periphery of the substrate). As a result, the plating speed in the center of the substrate is slower than that in the outer periphery of the substrate, and the thickness of the plating metal that is ultimately deposited on the substrate can differ greatly between the outer periphery and the center of the substrate.

[0006] On the other hand, in recent years, the miniaturization of substrate wiring has progressed, and there is a demand for a further thinning of the seed layer. As the seed layer becomes thinner, the electrical resistance of the seed layer increases, and the degree of voltage drop occurring on the substrate during electrolytic plating processing becomes larger. Therefore, as the seed layer becomes thinner, the uniformity of the film thickness of the plating metal deposited on the substrate becomes more and more hindered.

[0007] The present disclosure provides a technique that is advantageous for achieving uniform thickness of a plating metal deposited on a substrate in electrolytic plating.

[0008] One aspect of the present disclosure relates to a substrate liquid processing apparatus comprising a substrate holding section that rotatably holds a substrate, a first electrode that contacts the substrate held by the substrate holding section, a second electrode having an electrode opposing surface that is positioned facing the processing surface of the substrate held by the substrate holding section, a seal section that surrounds the processing surface, a plating solution supply section that supplies a plating solution to the processing surface of the substrate held by the substrate holding section, a current conductor that passes electricity through the first and second electrodes, and a control section, wherein the control section controls the plating solution supply section and the current conductor to output a control signal so as to pass electricity through the processing surface to perform a first electrolytic plating process when the plating solution is in contact with a first opposing range that is a portion of the electrode opposing surfaces, and outputs a control signal so as to control the plating solution supply section and the current conductor to perform a second electrolytic plating process after the first electrolytic plating process, when the plating solution is in contact with a second opposing range of the electrode opposing surfaces that is wider than the first opposing range.

[0009] According to the present disclosure, it is advantageous to make the thickness of the plating metal deposited on the substrate uniform in electrolytic plating. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of an example of a processing system. [Diagram 2] FIG. 2 is a diagram illustrating an example of a processing unit. [Diagram 3] FIG. 3 is an enlarged plan view of a portion of the second electrode, showing an example of the arrangement of a plurality of current-carrying terminals. [Figure 4] FIG. 4 is a diagram illustrating an example of a processing unit according to the first embodiment. [Diagram 5] FIG. 5 is a diagram illustrating another example of the processing unit according to the first embodiment. [Figure 6A]FIG. 6A is a diagram showing an example of the plating method according to the first embodiment. [Figure 6B] FIG. 6B is a diagram showing an example of the plating method according to the first embodiment. [Figure 6C] FIG. 6C is a diagram showing an example of the plating method according to the first embodiment. [Figure 6D] FIG. 6D is a diagram showing an example of the plating method according to the first embodiment. [Figure 6E] FIG. 6E is a diagram showing an example of the plating method according to the first embodiment. [Figure 6F] FIG. 6F is a diagram showing an example of the plating method according to the first embodiment. [Figure 6G] FIG. 6G is a diagram showing an example of the plating method according to the first embodiment. [Figure 6H] FIG. 6H is a diagram showing an example of the plating method according to the first embodiment. [Figure 6I] FIG. 6I is a diagram showing an example of the plating method according to the first embodiment. [Figure 7A] FIG. 7A is a diagram illustrating an example of a processing unit according to the second embodiment. [Figure 7B] FIG. 7B is a diagram showing an example of a planar state of the substrate, illustrating how the plating solution spreads on the substrate in the processing unit shown in FIG. 7A. [Figure 8] FIG. 8 is a diagram illustrating another example of the processing unit according to the second embodiment. [Figure 9] FIG. 9 is a diagram illustrating another example of the processing unit according to the second embodiment. [Figure 10A] FIG. 10A is a plan view showing an example of the second electrode. [Figure 10B] FIG. 10B is an enlarged view showing an example of the concave-convex pattern shown in FIG. 10A. [Figure 11A] FIG. 11A is a diagram showing a first example of the plating method according to the second embodiment. [Figure 11B] FIG. 11B is a diagram showing a first example of the plating method according to the second embodiment. [Figure 11C]FIG. 11C is a diagram showing a first example of the plating method according to the second embodiment. [Figure 11D] FIG. 11D is a diagram showing a first example of the plating method according to the second embodiment. [Figure 11E] FIG. 11E is a diagram showing a first example of the plating method according to the second embodiment. [Figure 11F] FIG. 11F is a diagram showing a first example of the plating method according to the second embodiment. [Figure 11G] FIG. 11G is a diagram showing a first example of the plating method according to the second embodiment. [Figure 11H] FIG. 11H is a diagram showing a first example of the plating method according to the second embodiment. [Figure 11I] FIG. 11I is a diagram showing a first example of the plating method according to the second embodiment. [Figure 12A] FIG. 12A is a diagram showing a second example of the plating method according to the second embodiment. [Figure 12B] FIG. 12B is a diagram showing a second example of the plating method according to the second embodiment. [Figure 12C] FIG. 12C is a diagram showing a second example of the plating method according to the second embodiment. [Figure 12D] FIG. 12D is a diagram showing a second example of the plating method according to the second embodiment. [Figure 12E] FIG. 12E is a diagram showing a second example of the plating method according to the second embodiment. [Figure 12F] FIG. 12F is a diagram showing a second example of the plating method according to the second embodiment. [Figure 12G] FIG. 12G is a diagram showing a second example of the plating method according to the second embodiment. [Figure 12H] FIG. 12H is a diagram showing a second example of the plating method according to the second embodiment. [Figure 12I] FIG. 12I is a diagram showing a second example of the plating method according to the second embodiment. [Figure 13A] FIG. 13A is a diagram showing a third example of the plating method according to the second embodiment. [Figure 13B]FIG. 13B is a diagram showing a third example of the plating method according to the second embodiment. [Figure 13C] FIG. 13C is a diagram showing a third example of the plating method according to the second embodiment. [Figure 13D] FIG. 13D is a diagram showing a third example of the plating method according to the second embodiment. [Figure 13E] FIG. 13E is a diagram showing a third example of the plating method according to the second embodiment. [Figure 13F] FIG. 13F is a diagram showing a third example of the plating method according to the second embodiment. [Figure 13G] FIG. 13G is a diagram showing a third example of the plating method according to the second embodiment. [Figure 13H] FIG. 13H is a diagram showing a third example of the plating method according to the second embodiment. [Figure 13I] FIG. 13I is a diagram showing a third example of the plating method according to the second embodiment. [Figure 14A] FIG. 14A is a plan view showing an electrode facing surface of a second electrode according to a first modified example. [Figure 14B] FIG. 14B is a diagram showing a processing unit according to the first modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] An embodiment of the present disclosure will be described with reference to the drawings.

[0012] Fig. 1 is a diagram showing an outline of an example of a processing system 80. The processing system 80 shown in Fig. 1 has a loading / unloading station 91 and a processing station 92. The loading / unloading station 91 includes a placement section 81 equipped with a plurality of carriers C, and a transport section 82 in which a first transport mechanism 83 and an exchange section 84 are provided. Each carrier C accommodates a plurality of substrates W in a horizontal state. The processing station 92 is provided with a plurality of processing units 10 installed on both sides of a transport path 86, and a second transport mechanism 85 that reciprocates along the transport path 86.

[0013] The substrate W is taken out of the carrier C by the first transport mechanism 83 and placed on the delivery section 84, and is taken out of the delivery section 84 by the second transport mechanism 85. The substrate W is then carried into the corresponding processing unit 10 by the second transport mechanism 85, and various processes are performed in the corresponding processing unit 10. Thereafter, the substrate W is taken out of the corresponding processing unit 10 by the second transport mechanism 85 and placed on the delivery section 84, and then returned to the carrier C of the placement section 81 by the first transport mechanism 83.

[0014] The processing system 80 includes a control unit 93. The control unit 93 is configured, for example, by a computer, and includes an arithmetic processing unit and a storage unit. The storage unit of the control unit 93 stores programs and data for various processes performed in the processing system 80. The arithmetic processing unit of the control unit 93 appropriately reads out and executes the programs stored in the storage unit, thereby controlling various mechanisms of the processing system 80 and performing various processes.

[0015] The programs and data stored in the storage unit of the control unit 93 may be those recorded in a computer-readable storage medium and installed into the storage unit from the storage medium. Examples of computer-readable storage media include a hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnet optical disk (MO), and a memory card.

[0016] FIG. 2 is a diagram illustrating an example of the processing unit 10. As shown in FIG.

[0017] The processing unit 10 includes a substrate holding section 11, a first electrode 12, a second electrode 13, a sealing section 14, a plating solution supply section 15, a current carrying section 16, and a processing solution supply section 17.

[0018] The substrate holding part 11 rotatably holds the substrate W under the control of the control part 93 (see FIG. 1). The substrate holding part 11 receives the substrate W from the second transport mechanism 85 (see FIG. 1) and holds it, and transfers the substrate W to the second transport mechanism 85 after all processing in the processing unit 10 is completed.

[0019] There is no limitation on the manner in which the substrate holding part 11 holds the substrate W. Typically, the substrate holding part 11 holds the substrate W by suctioning the back surface (particularly the central part) of the substrate W. When the substrate W is held by the substrate holding part 11, a processing surface Ws formed by the upper surface of the substrate W extends in the horizontal direction.

[0020] In this example, while a plating process described below is being performed, the substrate holding part 11 holds the substrate W without rotating it, but it may also rotate the substrate W. Also, while other processes (e.g., cleaning process, rinsing process, or drying process) are being performed on the substrate W, the substrate holding part 11 may or may not rotate the substrate W.

[0021] The first electrode (negative electrode) 12 is provided so as to be able to come into contact with the substrate W held by the substrate holding part 11. The first electrode 12 shown in FIG. 2 is supported by a first electrode support part 25, and is positioned closer to the outer periphery of the substrate W than the seal part 14.

[0022] The first electrode support part 25 is movably supported by the first electrode moving part 27. The first electrode moving part 27 moves the first electrode support part 25 under the control of the control part 93, so that the first electrode 12 can be disposed at a position (retracted position) away from the substrate W and at a position (processing position) in contact with the outer periphery of the substrate W (particularly the upper surface of the substrate W). The movement direction of the first electrode 12 is not limited, and it may move in the height direction (up and down direction in FIG. 2) or in the horizontal direction.

[0023] The second electrode (positive electrode) 13 has an electrode facing surface 13s. The electrode facing surface 13s is disposed at a position facing a processing surface Ws of the substrate W held by the substrate holding part 11 during plating processing.

[0024] 2, for the sake of convenience, the second electrode 13 is depicted as having a flat plate shape, and the electrode facing surface 13s is depicted as extending parallel to the horizontal direction. However, as described below, the second electrode 13 may have a shape other than a flat plate. Also, the electrode facing surface 13s may extend non-parallel to the horizontal direction.

[0025] The second electrode 13 is supported by a second electrode support part 26. The second electrode support part 26 is movably supported by a second electrode moving part 28. The second electrode moving part 28 moves the second electrode support part 26 under the control of the control part 93, so that the electrode facing surface 13s of the second electrode 13 can be disposed at a position (retracted position) away from the processing surface Ws of the substrate W and at a position (processing position) close to the processing surface Ws. The movement direction of the second electrode 13 is not limited, and it may move in the height direction or the horizontal direction.

[0026] The second electrode moving part 28 may rotate the second electrode support part 26 and the second electrode 13. The second electrode support part 26 and the second electrode 13 may be rotated by the second electrode moving part 28 about the rotation axis of the substrate W held by the substrate holding part 11 (the central axis of the substrate W).

[0027] The current-carrying unit 16 has a current-carrying terminal and a power source 37. The power source 37 is connected to the first electrode 12, and is connected to the second electrode 13 via the current-carrying terminal .

[0028] Under the control of the control unit 93, the current supply unit 16 applies electricity to the processing surface Ws of the substrate W held by the substrate holding unit 11 via the first electrode 12 and the second electrode 13. That is, as described below, the power source 37 applies electricity to the substrate W (particularly the processing surface Ws) in a state in which the first electrode 12 is in contact with the substrate W and the second electrode 13 is connected to the substrate W via a plating solution. The voltage value and current value of the electricity supplied by the current supply unit 16 can be freely set according to a prepared recipe.

[0029] Although the power source 37 is connected to the second electrode 13 via a single current-carrying terminal 35 in the example shown in FIG. 2, the power source 37 may be connected to the second electrode 13 via a plurality of current-carrying terminals 35 .

[0030] As the distance from the current-carrying terminal 35 increases, the degree of voltage drop due to the electrical resistance of the second electrode 13 increases, and the deposition rate of the plating metal on the processing surface Ws of the substrate W tends to decrease. Therefore, when multiple current-carrying terminals 35 are provided, by distributing the multiple current-carrying terminals 35 discretely over the entire second electrode 13, it is possible to suppress the voltage drop over the entire second electrode 13 and promote uniformity of the deposition rate of the plating metal over the entire processing surface Ws.

[0031] 3 shows an enlarged plan view of a portion of the second electrode 13, illustrating an example of the arrangement of a plurality of current-carrying terminals 35. In the example shown in Fig. 3, the second electrode 13 is divided into a plurality of virtual partitioned regions, each of which has a regular hexagonal planar shape, and a corresponding current-carrying terminal 35 is connected to the center of each virtual partitioned region. The size of each virtual partitioned region is appropriately determined taking into consideration the electrical resistance of the second electrode 13.

[0032] In this way, by arranging corresponding current-carrying terminals 35 at the generating points of multiple virtual partition areas having polygonal planar shapes, it is possible to reduce voltage drop in the second electrode 13 and apply a uniform voltage across the entire second electrode 13.

[0033] The seal portion 14 (see FIG. 2) is disposed so as to surround the processing surface Ws of the substrate W held by the substrate holding portion 11, thereby preventing leakage of liquid (particularly plating solution) from above the processing surface Ws.

[0034] 2 has an annular planar shape and is pressed against and comes into contact with the outer periphery of the upper surface of the substrate W, thereby surrounding the entire processing surface Ws formed by the upper surface (excluding the outer periphery) of the substrate W. The sealing unit 14 in this example is movably supported by the first electrode support part 25, and moves integrally with the first electrode 12.

[0035] The plating solution supply unit 15 supplies a plating solution to the processing surface Ws of the substrate W held by the substrate holding unit 11. In the processing unit 10 of the present embodiment, since electrolytic plating processing is performed on the substrate W, a plating solution not containing a reducing agent is supplied from the plating solution supply unit 15 to the processing surface Ws of the substrate W.

[0036] The plating solution supply section 15 shown in FIG. 2 includes a plating solution supply source 31, a plating solution supply nozzle 33 connected to the plating solution supply source 31 via a plating solution supply path 30, and a plating solution supply valve 32 provided in the plating solution supply path 30.

[0037] 2 is positioned so as to penetrate the central parts of the second electrode 13 and the second electrode support part 26, is supported by the second electrode support part 26, and is provided so as to be movable integrally with the second electrode 13. However, the installation manner of the plating solution supply nozzle 33 is not limited, and the plating solution supply nozzle 33 may be positioned at a location other than the central part of the second electrode 13 (for example, the outer edge part of the second electrode 13). In addition, a mesh-shaped second electrode 13 or a second electrode 13 having a plurality of holes formed by a punching process may be provided at the tip (i.e., the discharge port) of the plating solution supply nozzle 33.

[0038] The plating solution supply valve 32 adjusts the opening and closing and the opening degree of the plating solution supply path 30 under the control of the control unit 93, thereby changing whether or not the plating solution is discharged from the plating solution supply nozzle 33 and the amount of plating solution discharged.

[0039] With the sealing portion 14 pressed against the processing surface Ws of the substrate W, plating solution is ejected from the plating solution supply nozzle 33 toward the area of ​​the processing surface Ws surrounded by the sealing portion 14 (e.g., the center of the processing surface Ws), thereby forming a liquid film of plating solution on the processing surface Ws.

[0040] The processing liquid supply unit 17 supplies a processing liquid other than a plating liquid to the processing surface Ws of the substrate W held by the substrate holding unit 11. The processing liquid supply unit 17 is movably supported by the processing liquid moving unit 29, and is arranged at a position where the processing liquid is supplied to the processing surface Ws, and at a standby position where the processing liquid is not supplied to the processing surface Ws.

[0041] The composition and use of the processing liquid discharged from the processing liquid supply unit 17 are not limited. The processing liquid supply unit 17 can discharge multiple types of processing liquid for multiple uses. When the processing liquid supply unit 17 discharges multiple types of processing liquid, the processing liquid supply unit 17 may discharge two or more types of processing liquid from separate nozzles or from a common nozzle. When the processing liquid supply unit 17 discharges multiple types of processing liquid, a separate processing liquid supply unit 17 and processing liquid moving unit 29 may be provided for each processing liquid. The processing liquid discharged from the processing liquid supply unit 17 and supplied to the processing surface Ws of the substrate W may be, for example, a pre-processing liquid used in a pre-processing of the substrate W performed prior to plating processing, or a post-processing liquid used in a post-processing of the substrate W performed after plating processing.

[0042] In the above-described processing unit 10, the control unit 93 outputs a control signal to control the plating solution supply unit 15 and the current supply unit 16 so as to perform a second electrolytic plating process after performing a first electrolytic plating process.

[0043] The first electrolytic plating process is a plating process performed by passing electricity through the processing surface Ws of the substrate W while the plating solution is in contact with only a first opposing range, which is a portion of the electrode opposing surface 13s of the second electrode 13.

[0044] On the other hand, the second electrolytic plating process is a plating process performed by passing electricity through the processing surface Ws of the substrate W while a plating solution is in contact with a second opposing range (particularly the range including the first opposing range) of the electrode opposing surface 13s of the second electrode 13, which is wider than the first opposing range.

[0045] In the first electrolytic plating process, the plating process in the first processing region facing the first opposing range of the processing surface Ws of the substrate W can be promoted more than the plating process in other regions of the processing surface Ws. Therefore, by setting the region of the substrate W located far from the position where the first electrode 12 contacts (the central region of the processing surface Ws in this example) as the first processing region, the difference in film thickness of the plating metal on the processing surface Ws caused by the voltage drop can be reduced.

[0046] Next, a specific embodiment of the plating method (substrate solution processing method) will be described.

[0047] [First embodiment] Fig. 4 is a diagram showing an example of the processing unit 10 according to the first embodiment. Fig. 5 is a diagram showing another example of the processing unit 10 according to the first embodiment. Figs. 4 and 5 show only some elements constituting the processing unit 10, and other elements are omitted from the illustration.

[0048] In this embodiment, the area of ​​the electrode facing surface 13s of the second electrode 13 that faces the central region of the processing surface Ws of the substrate W held by the substrate holding part 11 protrudes relative to the processing surface Ws of the substrate W. That is, the central region of the electrode facing surface 13s is positioned relatively close to the processing surface Ws, and the peripheral region of the electrode facing surface 13s is positioned relatively far from the processing surface Ws.

[0049] 4 and 5 has a linearly inclined flat portion between the central region and the outer circumferential region, but the shape of the portion between the central region and the outer circumferential region of the second electrode 13 is not limited. For example, in the cross section of the second electrode 13, the electrode facing surface 13s may have a smoothly curved portion or a stepped portion between the central region and the outer circumferential region.

[0050] In this embodiment, the supply position of the plating solution Lp from the plating solution supply nozzle 33 (plating solution supply unit 15) is not limited, and the number of plating solution supply nozzles 33 that supply the plating solution Lp to the processing surface Ws of the substrate W is also not limited.

[0051] 4, the plating solution Lp may be supplied to the central region of the processing surface Ws of the substrate W from a single plating solution supply nozzle 33 provided in the central region (particularly on the central axis) of the second electrode 13. The plating solution supply nozzle 33 positioned to face the central region of the processing surface Ws of the substrate W held by the substrate holding part 11 can eject the plating solution Lp in the vertical direction toward the central region (e.g., on the central axis) of the processing surface Ws.

[0052] Alternatively, the plating solution Lp may be supplied to the outer circumferential region of the processing surface Ws of the substrate W from a plurality of plating solution supply nozzles 33 provided in the outer circumferential region of the second electrode 13 as shown in Fig. 5. The plating solution supply nozzle 33 positioned to face the outer circumferential region of the processing surface Ws of the substrate W held by the substrate holding part 11 can eject the plating solution Lp toward the outer circumferential region of the processing surface Ws. As shown in Fig. 5, ejecting the plating solution Lp from a plurality of plating solution supply nozzles 33 arranged at positions spaced apart from each other is advantageous in raising the liquid level of a puddle of the plating solution Lp formed on the processing surface Ws uniformly over the entire processing surface Ws.

[0053] 6A to 6I are diagrams showing an example of a plating method (substrate solution processing method) according to the first embodiment.

[0054] 6A to 6I show only some of the elements constituting the processing unit 10, and the other elements are omitted. Although Fig. 6A to 6I show the processing unit 10 shown in Fig. 4, the plating method can be carried out in a similar manner when another processing unit 10 (for example, the processing unit 10 shown in Fig. 5) is used.

[0055] The plating method described below is performed by appropriately operating each device constituting the processing unit 10 (substrate liquid processing apparatus) under the control of the control unit 93.

[0056] First, the substrate W is received and held by the substrate holding part 11 (FIG. 6A). At this time, the first electrode 12, the second electrode 13, the seal part 14 and the plating solution supply nozzle 33 are disposed at retracted positions away from the substrate W.

[0057] Thereafter, if necessary, a processing liquid is supplied from the processing liquid supply unit 17 to the processing surface Ws of the substrate W, and pre-processing (eg, cleaning) of the processing surface Ws is performed (FIG. 6B).

[0058] Thereafter, if necessary, the processing liquid is removed from the processing surface Ws, and the processing surface Ws is dried (FIG. 6C). In this example, the processing liquid is removed and the processing surface Ws is dried by rotating the substrate W by the substrate holder 11.

[0059] During the above-mentioned pretreatment and drying treatment of the treatment surface Ws, the first electrode 12, the second electrode 13, the seal portion 14, and the plating solution supply nozzle 33 remain disposed at the retreated positions.

[0060] Thereafter, the first electrode 12, the second electrode 13, the seal portion 14, and the plating solution supply nozzle 33 are placed at the processing position (FIG. 6D). As a result, the first electrode 12 and the seal portion 14 are positioned so as to contact the outer periphery of the substrate W, and the electrode facing surface 13s of the second electrode 13 faces the processing surface Ws of the substrate W at a position close to but distant from the processing surface Ws. As a result, a closed space is created above the processing surface Ws, partitioned by the substrate W, the seal portion 14, and the second electrode 13. In particular, the seal portion 14 is pressed against the upper surface of the substrate W, and the seal portion 14 and the substrate W are placed in a liquid-tight state.

[0061] Thereafter, the plating solution Lp is discharged from the plating solution supply nozzle 33 arranged at the processing position toward the closed space above the processing surface Ws, and the plating solution Lp is supplied to the processing surface Ws of the substrate W. The supply speed (flow rate) of the plating solution Lp from the plating solution supply nozzle 33 can be changed by the plating solution supply unit 15 (plating solution supply valve 32 (see FIG. 2)) under the control of the control unit 93, and can be freely set according to a recipe prepared in advance.

[0062] The plating solution Lp supplied from the plating solution supply nozzle 33 onto the processing surface Ws is blocked by the seal portion 14 and accumulates on the processing surface Ws to form a liquid film.

[0063] During application of the plating solution Lp to the processing surface Ws of the substrate W, the surface layer (seed layer) of the processing surface Ws may react with the plating solution Lp and dissolve. From the viewpoint of suppressing such dissolution of the surface layer of the processing surface Ws, it is preferable to pass electricity through the processing surface Ws from the initial stage of supplying the plating solution Lp to the processing surface Ws to promote the growth of the plating metal on the processing surface Ws.

[0064] For example, the control unit 93 may output a control signal to control the plating solution supply unit 15 and the current supply unit 16 to start supplying the plating solution Lp to the processing surface Ws after starting current supply to the processing surface Ws. In this case, deposition of plating metal due to a plating reaction is promoted on the processing surface Ws at the same time as the supply of the plating solution Lp to the processing surface Ws starts. As a result, it is possible to suppress the surface layer of the processing surface Ws from dissolving into the plating solution Lp.

[0065] As the plating solution Lp is supplied from the plating solution supply nozzle 33, the liquid level of the puddle of the plating solution Lp on the processing surface Ws gradually rises, and the plating solution Lp reaches a height position where it contacts the electrode facing surface 13s of the second electrode 13 (FIG. 6E). As described above, the electrode facing surface 13s in this embodiment is positioned relatively close to the processing surface Ws in its central region. Therefore, only a part of the electrode facing surface 13s (i.e., the central region) is locally immersed in the plating solution Lp first.

[0066] In this manner, with the electrode facing surface 13s of the second electrode 13 partially in contact with the plating solution Lp, electricity is passed through the processing surface Ws of the substrate W by the current conductor 16, and a first electrolytic plating process is performed. That is, with the first electrode 12 in contact with the substrate W and with the plating solution Lp in contact with a partial range (first facing range) of the electrode facing surface 13s of the second electrode 13 disposed at a position facing the processing surface Ws, electricity is passed through the processing surface Ws via the first electrode 12 and the second electrode 13.

[0067] As a result, deposition of plating metal by electrolytic plating reaction progresses locally in the area of ​​the treatment surface Ws facing the first facing area of ​​the electrode facing surface 13s.

[0068] The position and size of the first facing range of the electrode facing surface 13s are not limited. However, the first facing range is determined so as to cover the range of the processing surface Ws where the deposition of the plating metal is relatively slow due to a voltage drop. Therefore, the range including the center of the electrode facing surface 13s (i.e., the range facing the central region of the processing surface Ws of the substrate W) is set as the first facing range.

[0069] In reality, electricity also flows over the entire treatment surface Ws during the first electrolytic plating process, and plating metal may also be deposited on the portion of the treatment surface Ws that faces the portion of the electrode facing surface 13s that is not immersed in the plating solution Lp. However, deposition of plating metal progresses more actively on the portion of the treatment surface Ws that faces the portion of the electrode facing surface 13s that is immersed in the plating solution Lp than on the portion of the treatment surface Ws that faces the portion of the electrode facing surface 13s that is not immersed in the plating solution Lp.

[0070] The control unit 93 may output a control signal to control the plating solution supply unit 15 and the current supply unit 16 to stop the supply of the plating solution Lp to the processing surface Ws for at least a part of the time during which the first electrolytic plating process is performed. That is, the supply of the plating solution Lp to the closed space above the processing surface Ws may be stopped once before the plating solution Lp comes into contact with a maximum electrode contact area, which is the maximum area of ​​the electrode facing surface 13s that comes into contact with the plating solution Lp.

[0071] Alternatively, the control unit 93 may output a control signal to control the plating solution supply unit 15 and the current supply unit 16 to continue the supply of the plating solution Lp to the processing surface Ws without interruption while the first electrolytic plating process is being performed. In this case, the first opposing range of the electrode opposing surface 13s that is in contact with the plating solution Lp while the first electrolytic plating process is being performed varies over time and gradually expands.

[0072] Then, while electricity is being applied to the processing surface Ws of the substrate W, further plating solution Lp is supplied from the plating solution supply nozzle 33 to the processing surface Ws. This causes the area of ​​the electrode facing surface 13s of the second electrode 13 that is immersed in the plating solution Lp to gradually expand. As the supply of the plating solution Lp from the plating solution supply nozzle 33 proceeds in this manner, the area of ​​the electrode facing surface 13s that is immersed in the plating solution Lp gradually expands, and as a result, the area of ​​the processing surface Ws on which the plating metal is actively deposited gradually expands.

[0073] Then, when the plating solution Lp comes into contact with the maximum electrode contact area of ​​the electrode facing surface 13s, the discharge of the plating solution Lp from the plating solution supply nozzle 33 is stopped, and the supply of the plating solution Lp to the closed space above the processing surface Ws is terminated (Figure 6F).

[0074] The maximum electrode contact area referred to here is typically the entire electrode opposing surface 13s, and the entire electrode opposing surface 13s comes into contact with the plating liquid Lp by filling the closed space above the treatment surface Ws with the plating liquid Lp without any gaps.

[0075] However, the maximum electrode contact area does not necessarily have to be the entire electrode facing surface 13s. The supply of the plating solution Lp from the plating solution supply nozzle 33 to the closed space above the processing surface Ws may be terminated in a state in which the closed space partially includes a space. In this case, the outer edge of the electrode facing surface 13s does not come into contact with the plating solution Lp.

[0076] The control unit 93 in this embodiment outputs a control signal to control the plating solution supply unit 15 (plating solution supply valve 32) so as to bring the plating solution into contact with the entire maximum electrode contact area over a period of 5 seconds or more from the start of supply of the plating solution Lp to the processing surface Ws. For example, the plating solution Lp may come into contact with the entire maximum electrode contact area over a period of 10 seconds or more, 1 minute or more, or 10 minutes or more (usually about 10 seconds to 5 minutes) from the start of supply of the plating solution Lp to the processing surface Ws.

[0077] In this example, from the start of supply of the plating solution Lp to the processing surface Ws until a predetermined time has elapsed after the supply of the plating solution Lp to the processing surface Ws is stopped, electricity is continuously applied to the processing surface Ws by the current supply unit 16, and deposition of the plating metal on the processing surface Ws continues. In this manner, the state in which the plating solution Lp is in contact with the maximum electrode contact area of ​​the electrode facing surface 13s and electricity is applied to the processing surface Ws continues for a while.

[0078] Then, when the plating metal has been sufficiently deposited on the treatment surface Ws, the current flow to the treatment surface Ws is stopped, and the plating process of the treatment surface Ws is completed.

[0079] The control unit 93 of this embodiment outputs control signals so that the above-mentioned series of plating processes are carried out as follows.

[0080] That is, the time during which electricity flows through the processing surface Ws in a state where the plating solution Lp is in contact with the maximum electrode contact area of ​​the electrode opposing surface 13s is represented by "Tm". Also, the time during which electricity flows through the processing surface Ws in a state where the plating solution Lp is in contact with an area of ​​the electrode opposing surface 13s narrower than the maximum electrode contact area is represented by "Tn". In this case, the control unit 93 performs plating by controlling the current supply unit 16 (e.g., the power source 37) so that the time Tn is longer than the time Tm (i.e., so that "Tn>Tm" is satisfied).

[0081] When the plating process is completed, the first electrode 12, the second electrode 13, the seal portion 14 and the plating solution supply nozzle 33 are placed in the retreated positions (FIG. 6G).

[0082] Thereafter, a rinsing liquid Lr (eg, DIW (deionized water)) is supplied to the processing surface Ws of the substrate W by the processing liquid supply unit 17, and the plating liquid Lp is washed away from the processing surface Ws (FIG. 6H; rinsing process).

[0083] Thereafter, the substrate W is rotated by the substrate holder 11 to dry (spin-dry) the processing surface Ws (FIG. 6I; drying process). The second electrode 13 (particularly the electrode facing surface 13s), the seal portion 14, and the first electrode 12 are appropriately washed at the retreated position.

[0084] As described above, according to this embodiment, in the initial stage of plating, while only a portion (central region) of the electrode facing surface 13s of the second electrode 13 is in contact with the plating solution Lp, the formation of a plating metal film in the central region of the processing surface Ws of the substrate W can be intensively promoted. Then, by gradually supplying the plating solution Lp to the closed space above the processing surface Ws while the processing surface Ws is energized, the area of ​​the second electrode 13 immersed in the plating solution Lp gradually expands toward the outer periphery, and the area of ​​the second electrode 13 contributing to electrolytic plating gradually expands toward the outer periphery. Then, in the final stage of plating, the formation of a plating metal film is promoted over the entire processing surface Ws.

[0085] This allows the effect of "a slowdown in the deposition rate of the plating metal in the central region of the processing surface Ws" caused by a voltage drop during plating to be mitigated by "local promotion of deposition of the plating metal in the central region of the processing surface Ws" in the initial stage of plating. In this way, by gradually expanding the area in which the plating metal is deposited from the center to the outer periphery of the processing surface Ws, the plating metal can ultimately be deposited with an appropriate film thickness over the entire processing surface Ws. In other words, at the stage where the plating process is completed, the difference in the film thickness of the plating metal between the central region and the outer periphery of the processing surface Ws can be reduced, and the uniformity of the film thickness of the plating metal deposited on the substrate W can be improved.

[0086] In addition, by adjusting the supply speed of the plating solution Lp from the plating solution supply nozzle 33 to the closed space above the processing surface Ws in accordance with the voltage drop characteristics in the plating process, the uniformity of the plating metal film thickness on the processing surface Ws can be improved even more effectively.

[0087] Conventionally, the uniformity of the plating metal film thickness has been improved by reducing the difference in plating reaction time between regions of the processing surface Ws, and the plating liquid Lp is spread over the entire processing surface Ws in a short time from the start of the supply of the plating liquid Lp. In other words, conventionally, the uniformity of the plating metal film thickness on the processing surface Ws has been achieved by shortening as much as possible the time from the start of the supply of the plating liquid Lp to the processing surface Ws to the time when the entire processing surface Ws is covered with the plating liquid Lp.

[0088] On the other hand, in this embodiment, the area of ​​the second electrode 13 (electrode facing surface 13s) in contact with the plating solution Lp on the processing surface Ws is expanded stepwise or continuously over time. This actively changes the substantial plating reaction time between regions of the processing surface Ws based on the inherent strength of the electrolytic plating reaction according to the voltage drop characteristics, and the film thickness of the plating metal on the processing surface Ws is made uniform.

[0089] Furthermore, even in cases where it is difficult to deposit sufficient plating metal in the center of the treatment surface Ws using conventional methods due to the high electrical resistance of the surface layer (seed layer) of the treatment surface Ws, according to this embodiment, it is possible to deposit sufficient plating metal in the center of the treatment surface Ws.

[0090] [Second embodiment] In this embodiment, elements that are the same as or correspond to those in the above-described first embodiment are given the same reference numerals, and detailed description thereof will be omitted.

[0091] Fig. 7A is a diagram showing an example of a processing unit 10 according to the second embodiment. Fig. 7A shows only some elements constituting the processing unit 10, and other elements are not shown. Fig. 7B is a diagram showing an example of a planar state of the substrate W, showing how the plating solution Lp spreads on the substrate W in the processing unit 10 shown in Fig. 7A.

[0092] 7A, the second electrode 13 has a flat plate shape, and the electrode facing surface 13s extends parallel to the horizontal direction. However, the specific shape of the second electrode 13 (for example, the electrode facing surface 13s) is not limited.

[0093] 8 and 9 are diagrams showing another example of the processing unit 10 according to the second embodiment.

[0094] For example, as shown in FIG. 8, the central region of the electrode facing surface 13s may have a downwardly convex shape compared to the outer edge of the electrode facing surface 13s. In this case, the area of ​​the electrode facing surface 13s facing the central region of the processing surface Ws of the substrate W held by the substrate holding unit 11 protrudes with respect to the processing surface Ws. According to the example shown in FIG. 8, the closed space directly above the central region of the processing surface Ws of the substrate W is small, so that the plating solution Lp supplied from the plating solution supply nozzle 33 can be easily spread over the processing surface Ws. Also, according to the example shown in FIG. 8, the distance between the central region of the processing surface Ws of the substrate W and the second electrode 13 can be shortened, so that the deposition of the plating metal in the central region of the processing surface Ws can be effectively promoted.

[0095] Alternatively, as shown in Fig. 9, the central region of the electrode facing surface 13s may have a downwardly concave shape compared to the outer edge portion of the electrode facing surface 13s. In this case, the area of ​​the electrode facing surface 13s facing the central region of the processing surface Ws of the substrate W held by the substrate holding part 11 is concave with respect to the processing surface Ws. According to the example shown in Fig. 9, since the closed space directly above the central region of the processing surface Ws of the substrate W is large, the plating solution Lp supplied from the plating solution supply nozzle 33 can be spread slowly on the processing surface Ws, and the spreading state of the plating solution Lp on the processing surface Ws can be easily controlled.

[0096] The plating solution supply nozzle 33 is provided in the central region of the second electrode 13, as in the example shown in FIG. 4, and supplies the plating solution Lp onto the central region of the processing surface Ws. As a result, the plating solution Lp gradually spreads from the central region of the processing surface Ws outward while contacting the processing surface Ws and the electrode opposing surface 13s. That is, the plating solution Lp supplied to the processing surface Ws partially contacts both the central region of the electrode opposing surface 13s and the central region of the processing surface Ws before spreading over the entire surface of the processing surface Ws. Then, the plating solution Lp gradually expands the contact area between the processing surface Ws and the electrode opposing surface 13s while maintaining a state of contact with the processing surface Ws and the electrode opposing surface 13s.

[0097] The distance between the second electrode 13 (electrode opposing surface 13s) and the substrate W (processing surface Ws) is set to a distance (e.g., about 1 to 3 mm) that maintains a pool of plating liquid Lp between the processing surface Ws and the electrode opposing surface 13s due to the surface tension of the plating liquid Lp.

[0098] In this example, with the first electrode 12, the second electrode 13, the seal portion 14, and the plating solution supply nozzle 33 disposed at the processing position, the plating solution Lp is supplied from the plating solution supply nozzle 33 to the closed space above the processing surface Ws, and the first electrolytic plating process is performed. That is, with the plating solution Lp in contact with the first opposing range, which is a part of the electrode opposing surface 13s, electricity is applied to the processing surface Ws, and the first electrolytic plating process is performed.

[0099] In the above-described first embodiment, the control unit 93 outputs a control signal to perform the first electrolytic plating process in a state in which the plating liquid Lp is in contact with the entire maximum range (maximum substrate contact range) of the processing surface Ws that is in contact with the plating liquid Lp, as shown in FIG. 4.

[0100] On the other hand, in this embodiment, as shown in Figures 7A to 9, the control unit outputs a control signal to perform the first electrolytic plating process in a state in which the plating solution Lp is in contact with only a portion of the maximum substrate contact range of the processing surface Ws.

[0101] In this embodiment, as in the first embodiment described above, dissolution of the surface layer (seed layer) of the treatment surface Ws into the plating solution Lp can be suppressed by starting the flow of current to the treatment surface Ws prior to application of the plating solution Lp to the treatment surface Ws.

[0102] Thereafter, the plating solution Lp is further supplied onto the processing surface Ws from the plating solution supply nozzle 33, and in a state in which the plating solution Lp is supplied to the entire processing surface Ws, electricity is passed through the processing surface Ws to perform plating. In this embodiment, the plating solution Lp is filled in the entire closed space above the processing surface Ws, and the plating solution Lp is in contact with the entire electrode opposing surface 13s of the second electrode 13 (maximum electrode contact range), and then plating is performed.

[0103] In addition, the electrode facing surface 13s of the second electrode 13 may have a configuration that promotes uniform spreading of the plating solution Lp on the processing surface Ws of the substrate W (i.e., the plating solution Lp on the electrode facing surface 13s) in a radial direction from the center of the processing surface Ws.

[0104] Fig. 10A is a plan view showing an example of the second electrode 13. Fig. 10B is an enlarged view showing an example of the concave-convex pattern 40 shown in Fig. 10A.

[0105] The electrode facing surface 13s may have, for example, a concave-convex pattern 40 arranged concentrically around the central axis (rotation axis) of the second electrode 13. In the example shown in Fig. 10A and Fig. 10B, the concave-convex pattern 40 is formed by a collection of punched holes formed in the second electrode 13. The specific configuration of the concave-convex pattern 40 is not limited, and for example, each punched hole may have a diameter of about 0.5 to 1 mm. Also, instead of a plurality of punched holes, the concave-convex pattern 40 may be formed by a collection of a plurality of minute protrusions (for example, a plurality of minute protrusions having a protrusion height of about 0.5 mm or less).

[0106] The second electrode 13 (particularly the electrode facing surface 13s) may contain a plurality of materials having different surface properties, instead of the physical uneven pattern 40, which may promote uniform spreading of the plating solution Lp in the radial direction on the processing surface Ws. For example, the second electrode 13 may contain a plurality of materials having different contact angles with the plating solution Lp and arranged concentrically, and the plurality of materials may be arranged concentrically around the central axis of the second electrode 13.

[0107] Other configurations of the processing unit 10 shown in FIG. 7A are similar to those of the processing unit 10 shown in FIG. 4 according to the above-described first embodiment.

[0108] Next, an example of a plating method according to this embodiment will be described.

[0109] In the following, first to third examples of a plating method performed by the processing unit 10 shown in Fig. 7A will be described. Processing units 10 having other configurations (see Figs. 8 to 10B) can also perform the following plating methods in a similar manner.

[0110] 11A to 11I are diagrams showing a first example of a plating method according to the second embodiment.

[0111] 11A to 11I show only some of the elements constituting the processing unit 10, and the other elements are omitted. In this example, each device constituting the processing unit 10 (substrate liquid processing apparatus 1) operates appropriately under the control of the control unit 93 to perform each processing step.

[0112] First, the substrate W is received and held by the substrate holder 11 (FIG. 11A).

[0113] Thereafter, as necessary, a processing liquid is supplied from the processing liquid supply unit 17 to the processing surface Ws of the substrate W to perform pre-processing of the processing surface Ws (FIG. 11B), and the processing liquid is removed from the processing surface Ws to dry the processing surface Ws (FIG. 11C). In the pre-processing of this example, a chemical reaction of the processing liquid is utilized to perform pre-processing of the processing surface Ws.

[0114] Thereafter, the first electrode 12, the second electrode 13, the seal portion 14, and the plating solution supply nozzle 33 are placed at the processing position (FIG. 11D). Then, the plating solution Lp is discharged from the plating solution supply nozzle 33 toward the closed space above the processing surface Ws of the substrate W, and the plating solution Lp is supplied to the processing surface Ws (FIG. 11E). As a result, only a part of the processing surface Ws and only a part of the electrode facing surface 13s are locally in contact with the plating solution Lp.

[0115] In this state in which the electrode facing surface 13s of the second electrode 13 is partially in contact with the plating solution Lp, electricity is applied to the processing surface Ws of the substrate W by the current conductor 16, and a first electrolytic plating process is carried out.

[0116] Then, the plating solution Lp is further supplied from the plating solution supply nozzle 33 to the processing surface Ws of the substrate W, so that the area of ​​the electrode facing surface 13s covered with the plating solution Lp gradually expands.

[0117] While the plating solution Lp is being spread on the processing surface Ws as described above, the substrate holder 11 may rotate the substrate W, and the second electrode moving unit 28 may rotate the second electrode 13 via the second electrode support unit 26. By rotating the substrate W and / or the second electrode 13 in this manner, the plating solution Lp can be encouraged to be uniformly spread in the radial direction while being in contact with the processing surface Ws and the electrode facing surface 13s. In this case, the rotation speed of the substrate W and the rotation speed of the second electrode 13 are not limited, but are usually lower (e.g., several rpm to several tens of rpm) than the rotation speed of the spin drying process of the substrate W (e.g., 1000 rpm).

[0118] Then, when the plating solution Lp comes into contact with the maximum electrode contact area of ​​the electrode opposing surface 13s, the discharge of the plating solution Lp from the plating solution supply nozzle 33 is stopped, and the supply of the plating solution Lp to the closed space above the processing surface Ws is terminated (Figure 11F).

[0119] In this example, from the start of the supply of plating solution Lp to the treatment surface Ws until a predetermined time has elapsed after the supply of plating solution Lp to the treatment surface Ws is stopped, electricity is continuously passed through the treatment surface Ws by the current carrying section 16, and plating metal continues to accumulate on the treatment surface Ws.

[0120] Then, when the plating metal has been sufficiently deposited on the treatment surface Ws, the current to the treatment surface Ws is stopped, the plating process of the treatment surface Ws is terminated, and the first electrode 12, the second electrode 13, the seal portion 14 and the plating solution supply nozzle 33 are positioned to the retracted position (Figure 11G).

[0121] Thereafter, the processing liquid supply unit 17 supplies a rinsing liquid Lr to the processing surface Ws of the substrate W to rinse the plating liquid Lp from the processing surface Ws (FIG. 11H), and the substrate holder 11 rotates the substrate W to dry the processing surface Ws (FIG. 11I). Meanwhile, the second electrode 13 (particularly the electrode facing surface 13s), the seal unit 14, and the first electrode 12 are appropriately washed at the retracted position.

[0122] 12A to 12I are diagrams showing a second example of the plating method according to the second embodiment. In Fig. 12A to 12I, only some of the elements constituting the processing unit 10 are shown, and other elements are omitted.

[0123] In this example, after the substrate holder 11 holds the substrate W (FIG. 12A), pre-treatment is performed with the second electrode 13 and the plating solution supply nozzle 33 positioned at the treatment position (FIG. 12B).

[0124] That is, the pretreatment is performed in a state where the pretreatment liquid Lt1 is in contact with the processing surface Ws of the substrate W and the electrode facing surface 13s of the second electrode 13. This makes it possible to perform the pretreatment of both the processing surface Ws and the electrode facing surface 13s at the same time. In the pretreatment of this example, the chemical reaction of the processing liquid is utilized to perform the pretreatment of the processing surface Ws and the electrode facing surface 13s.

[0125] In the example shown in FIG. 12B, the sealing portion 14 and the first electrode 12 are placed in the retracted position while the pre-treatment is being performed.

[0126] 12B, the pretreatment liquid Lt1 used in the pretreatment is supplied onto the treatment surface Ws not through the treatment liquid supply unit 17 (see FIG. 2) but through the plating liquid supply nozzle 33. In this manner, the plating liquid supply nozzle 33 of this example functions not only as the plating liquid supply unit 15 but also as the treatment liquid supply unit 17.

[0127] A supply system (not shown) for the pretreatment liquid Lt1 can be connected in any manner to the plating solution supply nozzle 33. As an example, a flow path switching valve may be provided in a common flow path connected to the plating solution supply nozzle 33, and the flow path switching valve may switch the liquid supplied to the plating solution supply nozzle 33 between the plating solution Lp and the pretreatment liquid Lt1.

[0128] Thereafter, the substrate holder 11 rotates the substrate W to remove the pre-treatment liquid Lt1 from the treatment surface Ws, and the treatment surface Ws is dried (FIG. 12C). In this drying process, in the example shown in FIG. 12C, the second electrode 13 and the plating solution supply nozzle 33 remain positioned at the treatment position, and the sealer 14 and the first electrode 12 remain positioned at the retracted position.

[0129] Thereafter, the first electrode 12, the second electrode 13, the seal portion 14, and the plating solution supply nozzle 33 are disposed at the processing position (FIG. 12D). Then, the plating solution Lp is discharged from the plating solution supply nozzle 33 toward the closed space above the processing surface Ws of the substrate W, and the plating solution Lp is supplied to the processing surface Ws (FIG. 12E).

[0130] Then, in a state in which only a portion of the electrode facing surface 13s and only a portion of the processing surface Ws are in local contact with the plating solution Lp, electricity is applied to the processing surface Ws by the current conductor 16, and a first electrolytic plating process is performed.

[0131] Then, the plating solution Lp is further supplied from the plating solution supply nozzle 33 to the processing surface Ws of the substrate W, and the area of ​​the electrode facing surface 13s covered with the plating solution Lp gradually expands. When the plating solution Lp contacts the maximum electrode contact area of ​​the electrode facing surface 13s, the discharge of the plating solution Lp from the plating solution supply nozzle 33 is stopped, and the supply of the plating solution Lp to the closed space above the processing surface Ws is terminated (FIG. 12F).

[0132] In this example, from the start of the supply of plating solution Lp to the treatment surface Ws until a predetermined time has elapsed after the supply of plating solution Lp to the treatment surface Ws is stopped, electricity is continuously passed through the treatment surface Ws by the current carrying section 16, and plating metal continues to accumulate on the treatment surface Ws.

[0133] When the plating metal is sufficiently deposited on the processing surface Ws, the current to the processing surface Ws is stopped, the plating process of the processing surface Ws is completed, and the first electrode 12 and the seal part 14 are placed in the retreated position (FIG. 12G). In the example shown in FIG. 12G, the second electrode 13 and the plating solution supply nozzle 33 remain placed in the processing position.

[0134] Thereafter, the post-processing liquid Lt2 (rinsing liquid) is supplied to the processing surface Ws of the substrate W by the plating solution supply nozzle 33, and the plating solution Lp is washed away from the processing surface Ws (FIG. 12H). In the example shown in FIG. 12H, the second electrode 13 and the plating solution supply nozzle 33 remain disposed at the processing position. Therefore, the plating solution Lp adhering to the processing surface Ws as well as the electrode opposing surface 13s is washed away by the post-processing liquid Lt2.

[0135] In the example shown in FIG. 12H, the post-processing liquid Lt2 used in the post-processing is supplied onto the processing surface Ws via the plating solution supply nozzle 33, not via the processing solution supply unit 17 (see FIG. 2). A supply system (not shown) for the post-processing liquid Lt2 used in the post-processing can be connected to the plating solution supply nozzle 33 in any manner. As an example, a flow path switching valve may be provided in a common flow path connected to the plating solution supply nozzle 33, and the flow path switching valve may switch the liquid supplied to the plating solution supply nozzle 33 between the plating solution Lp and the post-processing liquid Lt2. The post-processing liquid Lt2 may be the same as the pre-processing liquid Lt1, and the pre-processing liquid Lt1 and the post-processing liquid Lt2 may be supplied to the plating solution supply nozzle 33 using a common supply system.

[0136] Thereafter, with the first electrode 12, the second electrode 13, the seal part 14, and the plating solution supply nozzle 33 in the retracted position, the substrate W is rotated by the substrate holder 11 to dry the processing surface Ws (FIG. 12I). Meanwhile, the second electrode 13 (particularly the electrode facing surface 13s), the seal part 14, and the first electrode 12 are appropriately washed in the retracted position.

[0137] 13A to 13I are diagrams showing a third example of the plating method according to the second embodiment. In Fig. 13A to 13I, only some of the elements constituting the processing unit 10 are shown, and other elements are omitted.

[0138] In this example, after the substrate holding part 11 holds the substrate W, the first electrode 12, the second electrode 13, the seal part 14, and the plating solution supply nozzle 33 are placed at the processing position (FIG. 13A). Then, with the first electrode 12, the second electrode 13, the seal part 14, and the plating solution supply nozzle 33 placed at the processing position, pre-processing is performed using the pre-processing liquid Lt1 (FIGS. 13B and 13C).

[0139] That is, the pre-treatment liquid Lt1 is supplied from the plating solution supply nozzle 33 to the processing surface Ws of the substrate W (FIG. 13B), the entire closed space above the processing surface Ws is filled with the pre-treatment liquid Lt1, and the pre-treatment liquid Lt1 is applied to the entire processing surface Ws and the entire electrode opposing surface 13s (FIG. 13C).

[0140] The pretreatment in this example is performed by applying electricity to the treatment surface Ws by the current conductor 16 via the first electrode 12 and the second electrode 13 while the pretreatment liquid Lt1 is in contact with a part or the whole of each of the treatment surface Ws and the electrode opposing surface 13s. This causes an electrochemical reduction reaction in the pretreatment liquid Lt1, and oxides on the treatment surface Ws and the electrode opposing surface 13s are reduced and removed. Prior to the pretreatment of the treatment surface Ws by this electrochemical reduction reaction, the treatment surface Ws may be chemically pretreated with any treatment liquid.

[0141] Thereafter, a rinsing liquid Lr (eg, DIW) is supplied from the plating liquid supply nozzle 33 to the processing surface Ws, and the pretreatment liquid Lt1 is washed away from the processing surface Ws and the electrode opposing surface 13s (FIG. 13D).

[0142] 13A to 13I, a liquid draining portion 45 is provided so as to penetrate the seal portion 14, and the closed space above the processing surface Ws is communicated with the outside via the liquid draining portion 45. Therefore, as the rinsing liquid Lr is supplied to the closed space, the pre-processing liquid Lt1 in the closed space is pushed out to the outside via the liquid draining portion 45.

[0143] Thereafter, the plating solution Lp is discharged from the plating solution supply nozzle 33 toward the closed space above the processing surface Ws of the substrate W, and the plating solution Lp is supplied to the processing surface Ws (FIG. 13E). As the plating solution Lp is supplied to the closed space, the rinsing solution Lr in the closed space is pushed out to the outside via the liquid drainage section 45.

[0144] Then, with a portion of the electrode facing surface 13s (i.e., the central area near the plating solution supply nozzle 33) in contact with the plating solution Lp, electricity is passed through the processing surface Ws of the substrate W by the current conductor 16, and a first electrolytic plating process is performed.

[0145] In addition, since the plating solution supply nozzle 33 in this example discharges the plating solution Lp toward the rinsing solution Lr in the closed space, a part of the plating solution Lp on the processing surface Ws is mixed with the rinsing solution Lr. Therefore, although a part of the plating solution Lp in the closed space is mixed with the rinsing solution Lr, the first electrolytic plating process in this example is performed in a state in which most of the plating solution Lp remains at a position facing the first facing range of the electrode facing surface 13s.

[0146] Then, the plating solution Lp is further supplied from the plating solution supply nozzle 33 to the processing surface Ws of the substrate W, so that the area of ​​the electrode facing surface 13s covered with the plating solution Lp gradually expands.

[0147] Then, the entire closed space above the processing surface Ws is filled with the plating solution Lp, and the plating solution Lp comes into contact with the maximum electrode contact area of ​​the electrode opposing surface 13s. When the plating solution Lp comes into contact with the maximum electrode contact area of ​​the electrode opposing surface 13s, the discharge of the plating solution Lp from the plating solution supply nozzle 33 is stopped, and the supply of the plating solution Lp to the closed space above the processing surface Ws is terminated (FIG. 13F).

[0148] In this example, from the start of the supply of plating solution Lp to the treatment surface Ws until a predetermined time has elapsed after the supply of plating solution Lp to the treatment surface Ws is stopped, electricity is continuously passed through the treatment surface Ws by the current carrying section 16, and plating metal continues to accumulate on the treatment surface Ws.

[0149] When the plating metal is sufficiently deposited on the processing surface Ws, the current to the processing surface Ws is stopped, the plating process of the processing surface Ws is completed, and the first electrode 12, the seal unit 14, and the liquid drain unit 45 are placed in the retreated position (FIG. 13G). In the example shown in FIG. 13G, the second electrode 13 and the plating solution supply nozzle 33 remain placed in the processing position.

[0150] Thereafter, the post-processing liquid Lt2 (rinsing liquid) is supplied to the processing surface Ws of the substrate W by the plating liquid supply nozzle 33, and the plating liquid Lp is washed away from the processing surface Ws and the electrode facing surface 13s (FIG. 13H).

[0151] Thereafter, with the second electrode 13 and the plating solution supply nozzle 33 in the retracted position, the substrate W is rotated by the substrate holder 11 to dry the processing surface Ws (FIG. 13I). Meanwhile, the second electrode 13 (particularly the electrode facing surface 13s), the sealer 14, and the first electrode 12 are appropriately washed in the retracted position.

[0152] As described above, in this embodiment as well, in the initial stage of the plating process, only the central region of the electrode facing surface 13s of the second electrode 13 is in contact with the plating solution Lp, and thus the formation of a plating metal film in the central region of the processing surface Ws of the substrate W can be promoted in a concentrated manner.

[0153] In particular, in the initial stage of the plating process, the surface to be treated Ws is energized to perform the plating process in a state in which the plating solution Lp is not attached to the outer periphery of the surface to be treated Ws, so that deposition of plating metal on the outer periphery of the surface to be treated Ws can be reliably prevented in the initial stage of the plating process.

[0154] [First Modification] Fig. 14A is a plan view showing an electrode facing surface 13s of a second electrode 13 according to the first modified example, and Fig. 14B is a diagram showing a processing unit 10 according to the first modified example.

[0155] Although second electrode 13 shown in FIGS. 14A and 14B has a flat plate shape, this modification is also applicable to second electrode 13 having a non-flat plate shape (electrode opposing surface 13s extending in a non-horizontal direction).

[0156] The electrode opposing surface 13s may be divided into a plurality of divided surfaces 13sm. The current supply unit 16 may be configured to change the electricity flowing through each of the plurality of divided surfaces 13sm among the plurality of divided surfaces 13sm under the control of the control unit 93 (see FIG. 1).

[0157] In the example shown in FIG. 14A, the electrode opposing surface 13s is divided into concentric circles around the central axis (axis of rotation) of the second electrode 13, and each concentric region is divided into a plurality of regions to define a plurality of partition surfaces 13sm.

[0158] Each of the partition surfaces 13sm is connected to a corresponding current-carrying terminal 35. Under the control of the control unit 93, the current-carrying unit 16 can change the voltage applied to each of the current-carrying terminals 35 independently of one another.

[0159] In the example shown in Figure 14B, each current terminal 35 is connected to a power source 37 via a current adjustment unit 50, and each current adjustment unit 50 adjusts the voltage of electricity flowing to the corresponding current terminal 35 under the control of the control unit 93.

[0160] For example, each energization adjustment unit 50 may include a variable resistor, and the resistance value of the variable resistor may be appropriately changed by the control unit 93. In this case, even if the same voltage is applied to each energization adjustment unit 50 by the energizing unit 16, the effective voltage applied to each energization terminal 35 is changed individually by the corresponding energization adjustment unit 50.

[0161] During plating, the effective voltage applied to each current-carrying terminal 35 is adjusted by the corresponding current-carrying adjusting unit 50 so that a relatively high voltage acts on the divided surface 13sm on the central side and a relatively low voltage acts on the divided surface 13sm on the outer periphery side. This allows plating to be performed so as to reduce the effect of the voltage drop of the second electrode 13, and makes it possible to make the thickness of the plating metal uniform over the entire treatment surface Ws.

[0162] The number of the energization terminals 35 and the energization adjustment units 50 assigned to each partition surface 13sm may be one or more.

[0163] The current supply unit 16 may individually change the voltage (effective voltage) directly applied to each current supply terminal 35, instead of providing the current supply adjustment unit 50. In this case as well, plating can be performed in such a way as to reduce the effect of voltage drop on the substrate W, and the thickness of the plating metal deposited on the treatment surface Ws can be made uniform.

[0164] [Other variations] In the above example, during the plating process, the second electrode 13 is positioned above the substrate W, but the second electrode 13 may be positioned below the substrate W. In this case as well, during the plating process, the processing surface Ws of the substrate W and the electrode opposing surface 13s of the second electrode 13 face each other via the plating solution Lp.

[0165] It should be noted that the embodiments and modifications disclosed in this specification are merely illustrative in all respects and are not to be construed as limiting. The above-mentioned embodiments and modifications can be omitted, substituted, and modified in various forms without departing from the scope and spirit of the appended claims. For example, the above-mentioned embodiments and modifications may be combined in part or in whole, and an embodiment other than the above-mentioned may be combined in part or in whole with the above-mentioned embodiment or modification.

[0166] Furthermore, the technical category in which the above-mentioned technical idea is embodied is not limited. For example, the above-mentioned substrate liquid processing apparatus may be applied to other apparatuses. Furthermore, the above-mentioned technical idea may be embodied by a computer program for causing a computer to execute one or more procedures (steps) included in the above-mentioned substrate liquid processing method. Furthermore, the above-mentioned technical idea may be embodied by a computer-readable non-transitory recording medium on which such a computer program is recorded.

Claims

1. a substrate holder that rotatably holds the substrate; a first electrode in contact with the substrate held by the substrate holder; a second electrode having an electrode facing surface disposed at a position facing a processing surface of the substrate held by the substrate holding portion; A seal portion surrounding the treatment surface; a plating solution supply unit that supplies a plating solution to the processing surface of the substrate held by the substrate holding unit; an electric current supply unit that supplies electricity to the processing surface of the substrate held by the substrate holding unit through the first electrode and the second electrode; A control unit, The control unit is outputting a control signal to control the plating solution supply unit and the current supply unit to cause electricity to flow through the treatment surface in a state in which the plating solution is in contact with a first opposing range, which is a portion of the electrode opposing surface, to perform a first electrolytic plating process; A substrate liquid processing apparatus that controls the plating solution supply unit and the current collector to output a control signal so as to pass electricity through the processing surface to perform a second electrolytic plating process after the first electrolytic plating process, while the plating solution is in contact with a second opposing range of the electrode opposing surface that is wider than the first opposing range.

2. The substrate liquid processing apparatus of claim 1, wherein the control unit outputs a control signal so that the time during which electricity flows through the processing surface while the plating liquid is in contact with a maximum electrode contact range, which is the maximum area of ​​the electrode opposing surface that contacts the plating liquid, is longer than the time during which electricity flows through the processing surface while the plating liquid is in contact with a range of the electrode opposing surface that is narrower than the maximum electrode contact range.

3. The substrate liquid processing apparatus of claim 2, wherein the control unit controls the plating solution supply unit to output a control signal so as to bring the plating solution into contact with the entire maximum electrode contact range for a period of 5 seconds or more after starting to supply the plating solution to the processing surface.

4. The substrate liquid processing apparatus according to any one of claims 1 to 3, wherein the control unit controls the plating solution supply unit and the current collector to output a control signal so as to stop the supply of the plating solution to the processing surface for at least a portion of the time while the first electrolytic plating process is being performed.

5. A substrate liquid processing apparatus according to any one of claims 1 to 3, wherein the area of ​​the electrode opposing surface that faces the central region of the processing surface of the substrate held by the substrate holding portion protrudes or recesses relative to the processing surface.

6. 4. The substrate liquid processing apparatus according to claim 1, wherein the plating solution supply unit discharges the plating solution toward a central region of the processing surface of the substrate held by the substrate holding unit.

7. 4. The substrate liquid processing apparatus according to claim 1, wherein the plating solution supply unit discharges the plating solution toward an outer periphery region of the processing surface of the substrate held by the substrate holding unit.

8. The substrate liquid processing apparatus according to any one of claims 1 to 3, wherein the control unit controls the plating solution supply unit and the electrical current supply unit to output a control signal so as to start supplying the plating solution to the processing surface after starting electrical current to the processing surface.

9. The electrode facing surface is divided into a plurality of divided surfaces, 4. The substrate liquid processing apparatus according to claim 1, wherein the current supplying section is capable of changing the amount of electricity flowing through each of the plurality of divided surfaces among the plurality of divided surfaces under the control of the control section.

10. The substrate liquid processing apparatus according to any one of claims 1 to 3, wherein the control unit outputs a control signal so as to perform the first electrolytic plating process while the plating solution is in contact with the entire maximum substrate contact range, which is the maximum range of the processing surface that comes into contact with the plating solution.

11. The substrate liquid processing apparatus according to any one of claims 1 to 3, wherein the control unit outputs a control signal so as to perform the first electrolytic plating process in a state in which the plating solution is in contact with only a portion of a maximum substrate contact range, which is the maximum range of the processing surface that comes into contact with the plating solution.

12. a step of performing a first electrolytic plating process by passing electricity through the processing surface via the first electrode and the second electrode in a state in which a first electrode is in contact with a substrate held by a substrate holding unit and a plating solution is in contact with a first opposing range, which is a partial range of an electrode opposing surface of a second electrode disposed at a position facing a processing surface of the substrate; A substrate liquid processing method, comprising: a second electrolytic plating process being performed by passing electricity through the processing surface while the plating solution is in contact with a second opposing area of ​​the electrode opposing surface that is wider than the first opposing area.

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