JP2005264304A - Electrolytic processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrolytic processing apparatus where an electrically conductive material provided on the surface of a substrate can be flatly processed, and further, depositions deposited on the surface of the object to be processed such as a substrate can be subjected to removing (washing) while, e.g., obviating CMP (Chemical Mechanical Polishing) or reducing the load in the CMP treatment as possible. <P>SOLUTION: The electrolytic processing apparatus is equipped with: an electrode part 46 provided with an electrode member 92 containing an electrode 86 and an ion exchanger 90 covering the surface of the electrode 86; a holding part for bringing the object to be processed into contact with the ion exchanger 90 in the electrode member 92 or holding the object to be processed thereto freely proximately; and a power source connected to an electrode 86 of the electrode member 92 in the electrode part 46, and at least an edge part in the face confronted with the object to be processed in the electrode 86 is provided with a roundness (chamfered part 102). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electrolytic processing apparatus, and more particularly to an electrolytic processing apparatus used for processing a conductive material formed on the surface of a substrate such as a semiconductor wafer or removing impurities adhering to the surface of the substrate. About.

  In recent years, as a wiring material for forming a circuit on a substrate such as a semiconductor wafer, the movement of using copper (Cu) having low electrical resistivity and high electromigration resistance instead of aluminum or aluminum alloy has become prominent. . This type of copper wiring is generally formed by embedding copper in a fine recess provided on the surface of the substrate. Methods for forming this copper wiring include chemical vapor deposition (CVD), sputtering, and plating, but in any case, copper is deposited on almost the entire surface of the substrate, and chemical mechanical polishing is performed. Unnecessary copper is removed by (CMP).

FIG. 1A to FIG. 1C show a manufacturing example of this type of copper wiring board W in the order of steps. As shown in FIG. 1A, an insulating film 2 such as an oxide film made of SiO ₂ or a low-k material film is deposited on a conductive layer 1a on a semiconductor substrate 1 on which a semiconductor element is formed. A contact hole 3 and a wiring groove 4 are formed by an etching technique. A barrier layer 5 made of TaN or the like is formed thereon, and a seed layer 7 is formed thereon as a power feeding layer for electrolytic plating by sputtering or CVD.

  Then, by plating the surface of the substrate W with copper, the contact hole 3 and the wiring groove 4 of the semiconductor substrate 1 are filled with copper as shown in FIG. A film 6 is deposited. Thereafter, the copper film 6 and the seed layer 7 on the insulating film 2 are removed by chemical mechanical polishing (CMP), and the surface of the copper film 6 filled in the contact hole 3 and the wiring groove 4 and the surface of the insulating film 2 Are almost coplanar. As a result, a wiring made of the copper film 6 is formed as shown in FIG.

  In recent years, as the miniaturization and high precision have progressed in the components of all devices, and the manufacturing in the submicron region has become common, the influence of the processing method itself on the characteristics of the material has been increasing. Under such circumstances, the machining method in which the tool removes the workpiece while physically destroying it, as in conventional machining, because many defects are generated in the workpiece by machining. As a result, the properties of the workpiece are deteriorated. Therefore, it becomes a problem how the processing can be performed without impairing the characteristics of the material.

  Special processing methods developed as means for solving this problem include chemical polishing, electrolytic processing, and electrolytic polishing. In contrast to conventional physical processing, these processing methods perform removal processing and the like by causing a chemical dissolution reaction. Therefore, defects such as work-affected layers and dislocations due to plastic deformation do not occur, and the problem of performing processing without impairing the properties of the above-described materials is achieved.

  In recent years, white metal or its oxide has been proposed as an electrode material for forming a capacitor using a ferroelectric on a semiconductor substrate. Among these, ruthenium has a good film forming property, and thus is being studied as a highly feasible material.

  Here, ruthenium deposited or adhered to the peripheral edge and the back surface of the substrate other than the circuit forming portion is not only unnecessary, but also causes cross-contamination in the subsequent substrate transport, storage, and various processing steps. Degradation of the dielectric performance can also occur. Therefore, it is necessary to completely remove these after the ruthenium film forming process and the ruthenium film are subjected to some treatment. Furthermore, for example, when ruthenium is used as the electrode material of the capacitor, a step of removing a part of the ruthenium film formed on the circuit forming portion is necessary.

  For example, the CMP process generally requires a considerably complicated operation, is complicated in control, and has a considerably long processing time. Furthermore, not only is it necessary to sufficiently perform post-cleaning of the substrate after polishing, but there are also problems such as a large load for waste liquid treatment of slurry and cleaning liquid. Therefore, there is a strong demand for omitting CMP itself or reducing this load. In the future, it is expected that the insulating film will also be changed to a low-k material having a low dielectric constant. This low-k material is weak in strength and cannot withstand the stress caused by CMP. Therefore, there is a demand for a process that enables planarization without applying stress to the substrate.

  In addition, a process of cutting with CMP while plating, such as chemical mechanical electropolishing, has been announced, but by adding machining to the plating growth surface, it will also promote abnormal growth of plating. , Causing problems with film quality.

Further, in the above-described electrolytic processing and electrolytic polishing, it is assumed that processing proceeds by electrochemical interaction between the workpiece and an electrolytic solution (aqueous solution of NaCl, NaNO ₃ , HF, HCl, HNO ₃ , NaOH, etc.). . Therefore, as long as an electrolytic solution containing such an electrolyte is used, it is inevitable that the workpiece is contaminated with the electrolytic solution.

  The present invention has been made in view of such problems of the prior art. For example, the conductive material provided on the substrate surface is flattened while omitting the CMP process itself or reducing the load of the CMP process as much as possible. It is another object of the present invention to provide an electrolytic processing apparatus that can process (or wash) deposits adhered to the surface of a workpiece such as a substrate.

  According to a first aspect of the present invention, there is provided an electrode portion having an electrode member having an electrode and an ion exchanger covering the surface of the electrode, and a workpiece to be held in contact with or close to the ion exchanger of the electrode member. And a power source connected to the electrode of the electrode member of the electrode portion, and at least an edge portion of a surface of the electrode facing the workpiece is rounded. This is an electrolytic processing apparatus.

  FIG. 2 shows the processing principle of the present invention. 2 shows that the ion exchanger 12a attached to the machining electrode 14 and the ion exchanger 12b attached to the feeding electrode 16 are brought into contact with or close to the surface of the workpiece 10 so that the machining electrode 14 and the feeding electrode 16 A state in which a liquid 18 such as ultrapure water is supplied from the liquid supply unit 19 between the processing electrode 14 and the power supply electrode 16 and the workpiece 10 while a voltage is applied therebetween via the power source 17 is shown.

  When using a liquid having a large resistance value, such as ultrapure water, it is preferable to “contact” the ion exchanger 12a with the surface of the workpiece 10, and thus the ion exchanger 12a is covered with the ion exchanger 12a. By bringing the workpiece 10 into contact with the surface, the electrical resistance can be reduced, the applied voltage can be reduced, and the power consumption can be reduced. Therefore, the “contact” in the processing according to the present invention is not “pressing” in order to give physical energy (stress) to the workpiece as in CMP, for example.

  Thereby, the water molecules 20 in the liquid 18 such as ultrapure water are dissociated into the hydroxide ions 22 and the hydrogen ions 24 by the ion exchangers 12a and 12b. For example, the generated hydroxide ions 22 are converted into the workpiece. The electric field between the electrode 10 and the processing electrode 14 and the flow of a liquid 18 such as ultrapure water are supplied to the surface of the workpiece 10 facing the processing electrode 14, and the hydroxylation in the vicinity of the workpiece 10 here. The density of the object ions 22 is increased, and the atoms 10a of the workpiece 10 and the hydroxide ions 22 are reacted. The reactant 26 produced by the reaction is dissolved in the ultrapure water 18 and removed from the workpiece 10 by the flow of the liquid 18 such as ultrapure water along the surface of the workpiece 10. Further, the reactant 26 produced by the reaction is immediately captured by the ion exchangers 12a and 12b by the ion exchange reaction. Thereby, the removal process of the surface layer of the to-be-processed object 10 is performed.

  As described above, this processing method purely performs the removal processing of the work piece only by the electrochemical interaction with the work piece, and the physical interaction between the polishing member such as CMP and the work piece. The processing principle is different from processing by mixing action and chemical interaction with chemical species in the polishing liquid. In this method, the part of the workpiece 10 that faces the machining electrode 14 is machined, and therefore the surface of the workpiece 10 can be machined into a desired surface shape by moving the machining electrode 14.

  In addition, since the electrolytic processing apparatus according to the present invention performs removal processing of a workpiece only by a dissolution reaction by electrochemical interaction, physical interaction and polishing between a polishing member such as CMP and the workpiece. The processing principle is different from processing by mixing chemical interaction with chemical species in the liquid. Therefore, it is possible to perform removal processing without damaging the properties of the material. For example, even a material having a low mechanical strength such as the above-mentioned Low-k material can be removed without exerting a physical interaction. Processing is possible. Further, even when compared with an ordinary electrolytic processing apparatus, a liquid of 500 μS / cm or less, preferably pure water, more preferably ultrapure water is used as the electrolytic solution, so that contamination on the surface of the workpiece is greatly reduced. In addition, the waste liquid after processing can be easily treated.

  When the ion exchanger is placed in a form that covers the electrodes, when applying a voltage between the electrodes (working electrode / feeding electrode), the electric field concentrates on the edge of the electrode, especially the surface facing the workpiece Will occur. The processed products (copper ions and copper hydroxide) generated by the reaction are preferentially captured and accumulated from the portion of the ion exchanger that contacts the edge where this electric field concentration occurs, Compared to other parts, the amount of accumulated processed product increases at the edge part. When the accumulated amount of processed product in a part of the ion exchanger reaches the ion exchange capacity or more, the electrons used for the ion exchange reaction are not covered via the reaction product accumulated in the ion exchanger, not on the surface of the ion exchanger. Since it is supplied to the work piece, the dissociation reaction of water molecules does not take place or is greatly reduced, and not only the desired work piece removal ability cannot be exhibited, but also the accumulated amount of reaction products of the ion exchanger. Therefore, it becomes impossible to use the ion exchange capacity of a part having a small amount to the maximum.

  In the present invention, the lifetime of the ion exchanger is reduced by reducing electric field concentration by rounding at least the edge of the surface of the electrode facing the workpiece, and by reducing local accumulation of the processed product. Can be extended.

  It is preferable that the electrode has a rectangular cross section and is arranged in parallel with the electrode portion, and a surface facing the workpiece is formed in a semicircular shape. When an electrode having a narrow width and extending in a long shape is used as an electrode, the entire surface facing the workpiece is made semicircular, whereby the processed product is locally applied to the ion exchanger covering the electrode. And the area close to or close to the workpiece of the ion exchanger can be reduced.

  The electrode may have a circular cross section and be arranged in parallel with the electrode portion. By using an electrode having a circular cross section and extending in a long shape as an electrode, local accumulation of processed products in the ion exchanger covering the electrode is reduced, and the workpiece of the ion exchanger is also reduced. The area in contact with or close to can be reduced.

  According to a second aspect of the present invention, there is provided an electrode portion having an electrode member having an electrode and an ion exchanger covering the surface of the electrode, and a workpiece to be held in contact with or close to the ion exchanger of the electrode member. And a power source connected to the electrode of the electrode member of the electrode part, and an insulator is covered with the ion exchanger on the surface of the electrode facing the workpiece. It is the electrolytic processing apparatus characterized by being equipped.

  When the ion exchanger is arranged so as to cover the electrodes, the portion where the distance between the electrodes and the workpiece is the shortest when processing is performed by applying a voltage between the electrodes (processing electrode-feeding electrode), that is, the workpiece Concentration of the electric field occurs on the surface facing the. Processed products (copper ions and copper hydroxides) generated by the reaction are preferentially captured and accumulated on the surface of the ion exchanger facing the workpiece where electric field concentration occurs. The amount of accumulated processed product increases on the surface opposite to that of the other part of the ion exchanger. When the accumulated amount of processed product in a part of the ion exchanger reaches the ion exchange capacity or more, the electrons used for the ion exchange reaction are not covered via the reaction product accumulated in the ion exchanger, not on the surface of the ion exchanger. Since it is supplied to the work piece, the dissociation reaction of water molecules does not take place or is greatly reduced, and not only the desired work piece removal ability cannot be exhibited, but also the accumulated amount of reaction products of the ion exchanger. Therefore, it becomes impossible to use the ion exchange capacity of a part having a small amount to the maximum.

  In the present invention, by interposing an insulator between the surface of the electrode facing the workpiece and the ion exchanger, electric field concentration is eliminated from the surface of the electrode facing the workpiece, and the above processed product is obtained. By relaxing the local accumulation of ions, the lifetime of the ion exchanger can be extended. Furthermore, if necessary, the distance between the contact point of the ion exchanger where the electric field concentration of the electrode occurs and the work piece is increased through the insulator, and the volume of the ion exchanger from the electric field concentration part to the work piece is increased. By doing so, the lifetime of the ion exchanger can be extended.

  The invention according to claim 3 is the electrolytic processing apparatus according to claim 2, wherein the electrode and the insulator are integrally formed. Thereby, the convenience of manufacture of the electrode provided with the insulator which has arbitrary height (thickness) or an arbitrary distance from an electric field concentration part to a to-be-processed object can be aimed at.

  According to a fourth aspect of the present invention, there is provided an electrode portion having an electrode member having an electrode and an ion exchanger covering the surface of the electrode, and a workpiece to be held in contact with or close to the ion exchanger of the electrode member. And a power source connected to the electrode of the electrode member of the electrode unit, the ion exchanger includes an ion exchanger in contact with or close to the workpiece and another ion exchanger, In the electrolytic processing apparatus, the ion exchanger in contact with or close to the electrode and the workpiece is at least partially insulated from each other via an insulator.

In the case of using an ion exchanger having a plurality of ion exchangers, if an ion exchanger that is in contact with or close to the workpiece and the electrode are directly in contact with each other, current is given priority to the ion exchanger. Therefore, the processed product accumulates intensively and locally, and the total amount of ion exchange of the ion exchanger including other ion exchangers cannot be utilized to the maximum. In particular, in the case of a thin ion exchange membrane such as Nafion (trademark of DuPont), the tendency becomes remarkable because the ion exchange capacity is small.
In the present invention, the electrode and the ion exchanger that is in contact with or close to the surface to be processed are at least partially insulated from each other via an insulator, and current is preferentially applied to the ion exchanger that is in contact with or close to the work piece. By preventing the flow of the ion exchanger, the effect of extending the life of the ion exchanger can be obtained.

According to a fifth aspect of the present invention, the insulator is interposed between an edge portion of a surface of the electrode facing the workpiece and an ion exchanger in contact with or close to the workpiece. The electrolytic processing apparatus according to claim 4, wherein:
The invention according to claim 6 is the electrolytic processing apparatus according to claim 4 or 5, wherein the electrode and the insulator are integrally formed. Thereby, the convenience of manufacture of the electrode provided with the insulator can be aimed at.

  According to a seventh aspect of the present invention, there is provided an electrode portion having an electrode member having an electrode and an ion exchanger covering the surface of the electrode, and a workpiece to be held in contact with or proximate to the ion exchanger of the electrode member. And a power source connected to the electrode of the electrode member of the electrode unit, the ion exchanger includes an ion exchanger in contact with or close to the workpiece and another ion exchanger, The electrolytic processing apparatus is characterized in that an ion exchanger in contact with or close to a workpiece and another ion exchanger are insulated from each other at least partially via an insulator.

  When an ion exchanger having a plurality of ion exchangers is used, processing products accumulate and grow in order from the ion exchanger in contact with the electrode. At this time, if the ion exchanger in contact with or close to the workpiece is in contact with another ion exchanger (for example, an ion exchanger in contact with the electrode), the processed product accumulated in the other ion exchanger is When the contact product spreads from the contact point to the ion exchanger that is in contact with or close to the workpiece and the processed product grows on the surface of the ion exchanger until it contacts the workpiece, a short circuit of the current occurs, which causes the ion exchanger. Cannot fully utilize the ion exchange capacity.

  In the present invention, the ion exchanger in contact with or close to the workpiece and the other ion exchanger are at least partially insulated from each other, and the processed product accumulated in the other ion exchanger contacts or approaches the workpiece. By preventing diffusion to the ion exchanger, the effect of extending the life of the ion exchanger can be obtained.

  The invention according to claim 8 is the electrolytic processing according to claim 7, wherein the periphery of the other ion exchanger excluding the surface facing the workpiece is integrally surrounded by the insulator. Device.

  According to the present invention, it is possible to perform, for example, electrolytic processing instead of CMP by electrochemical action while preventing physical damage to a workpiece such as a substrate and damaging the properties of the workpiece. Thus, the CMP process itself can be omitted, the load of the CMP process can be reduced, and further, deposits adhering to the surface of the workpiece such as a substrate can be removed (cleaned). In addition, the substrate can be processed using only pure water or ultrapure water, which eliminates the possibility of extra impurities, such as electrolytes, remaining on the surface of the substrate and remaining. Not only can the cleaning process after processing be simplified, but also the waste liquid treatment load can be extremely reduced. Furthermore, the lifetime of the ion exchanger covering the surface of the electrode can be extended and the production efficiency can be increased.

  Embodiments of a substrate processing apparatus according to the present invention will be described below in detail with reference to the drawings. In the following description, an example is shown in which a substrate is used as a workpiece and the substrate is processed by an electrolytic processing apparatus, but it goes without saying that the present invention can be applied to other than the substrate.

  FIG. 3 is a plan view showing the configuration of the substrate processing apparatus including the electrolytic processing apparatus according to the embodiment of the present invention. As shown in FIG. 3, this substrate processing apparatus includes, for example, a cassette containing a substrate W having a copper film 6 as a conductor film (workpiece) and a barrier layer 5 on its surface, as shown in FIG. A pair of load / unload units 30 as a loading / unloading unit for loading / unloading, a first cleaning device 31a for performing primary cleaning of the substrate, a second cleaning device 31b for performing secondary cleaning (finish cleaning) of the substrate, A reversing machine 32 for reversing the substrate W and an electrolytic processing apparatus 34 are provided. These devices are arranged in series, and a transfer robot 36 as a transfer device that transfers the substrate W between these devices and transfers is arranged in parallel with these devices. In addition, a monitor unit 38 that monitors a voltage applied between a processing electrode and a power supply electrode, which will be described later, or a current flowing between them, is adjacent to the load / unload unit 30 during electrolytic processing by the electrolytic processing apparatus 34. Are arranged.

  4 is a plan view showing the electrolytic processing apparatus 34 in the substrate processing apparatus, and FIG. 5 is a longitudinal sectional view of FIG. As shown in FIGS. 4 and 5, the electrolytic processing apparatus 34 includes an arm 40 that can move up and down and can reciprocate along a horizontal plane, and is suspended from the free end of the arm 40 so that the substrate W faces downward (face down). And a movable frame 44 to which the arm 40 is attached, a rectangular electrode portion 46, and a power source 48 connected to the electrode portion 46. In this embodiment, the size of the electrode portion 46 is set to be slightly larger than the outer diameter of the substrate W held by the substrate holding portion 42.

  As shown in FIGS. 4 and 5, a vertical movement motor 50 is installed on the upper part of the movable frame 44, and a ball screw 52 extending in the vertical direction is connected to the vertical movement motor 50. A base 40 a of the arm 40 is attached to the ball screw 52, and the arm 40 moves up and down via the ball screw 52 as the vertical movement motor 50 is driven. The movable frame 44 itself is also attached to a ball screw 54 that extends in the horizontal direction, and the movable frame 44 and the arm 40 reciprocate along a horizontal plane as the reciprocating motor 56 is driven.

  The substrate holding portion 42 is connected to a rotation motor 58 installed at the free end of the arm 40, and rotates (spins) as the rotation motor 58 is driven. Further, as described above, the arm 40 can move up and down and reciprocate in the horizontal direction, and the substrate holding part 42 can move up and down and reciprocate in the horizontal direction integrally with the arm 40. .

  A hollow motor 60 is installed below the electrode portion 46, and a drive end 64 is provided on the main shaft 62 of the hollow motor 60 at a position eccentric from the center of the main shaft 62. The electrode portion 46 is rotatably connected to the drive end 64 via a bearing (not shown) at the center thereof. Further, three or more rotation prevention mechanisms are provided in the circumferential direction between the electrode portion 46 and the hollow motor 60.

  FIG. 6A is a plan view showing a rotation prevention mechanism in this embodiment, and FIG. 6B is a cross-sectional view taken along line AA of FIG. As shown in FIGS. 6 (a) and 6 (b), there are three or more rotation prevention mechanisms (four in FIG. 6 (a)) in the circumferential direction between the electrode portion 46 and the hollow motor 60. 66 is provided. As shown in FIG. 6B, a plurality of recesses 68 and 70 are formed at equal intervals in the circumferential direction at corresponding positions on the upper surface of the hollow motor 60 and the lower surface of the electrode portion 46. Bearings 72 and 74 are mounted at the locations 68 and 70, respectively. One end portions of two shaft bodies 76 and 78 that are shifted by a distance “e” are inserted into the bearings 72 and 74, respectively, and the other end portions of the shaft bodies 76 and 78 are connected to each other by a connecting member 80. Here, the amount of eccentricity of the drive end 64 with respect to the center of the main shaft 62 of the hollow motor 60 is also the same as the distance “e” described above. Accordingly, as the hollow motor 60 is driven, the electrode portion 46 has a revolving motion that does not rotate, that is, a so-called scroll motion (translational rotation) with a distance “e” between the center of the main shaft 62 and the drive end 64 as a radius. Exercise).

  Next, the electrode part 46 in this embodiment will be described. The electrode part 46 in this embodiment includes a plurality of electrode members 82. 7 is a plan view showing the electrode portion 46 in this embodiment, FIG. 8 is a cross-sectional view taken along the line BB of FIG. 7, and FIG. 9 is a partially enlarged view of FIG. As shown in FIGS. 7 and 8, the electrode portion 46 includes a plurality of electrode members 82 extending in the X direction (see FIGS. 4 and 7), and these electrode members 82 are formed on a flat base 84. They are arranged in parallel.

  As shown in FIG. 9, each electrode member 82 includes an electrode 86 connected to a power source 48 (see FIGS. 4 and 5), an ion exchanger (ion exchange membrane) 90 that integrally covers the surface of the electrode 86, and It has. The ion exchanger 90 is attached to the electrode 86 by holding plates 85 disposed on both sides of the electrode 86.

Here, the following four points are required for the ion exchanger 90.
(1) Removal of processing product (including gas) This is because it affects the stability of the processing rate and the uniformity of the processing rate distribution. For this reason, it is preferable to use an ion exchanger having “water permeability” and “water absorption”. Here, “water permeability” means macroscopic permeability. That is, even if the material itself does not have water permeability, water can be passed by cutting holes and grooves in the member, and water permeability can be given. On the other hand, “water absorption” means the property of water soaking into the material.

(2) Stability of processing rate In order to stabilize the processing rate, it is considered preferable to stack a large number of ion exchange materials to ensure ion exchange capability.
(3) Flatness of work surface (step-resolving ability)
In order to ensure the flatness of the work surface, it is considered preferable that the surface smoothness of the work surface of the ion exchanger is good. Furthermore, it is considered that the harder the member, the higher the flatness of the processed surface (step difference elimination ability).
(4) Long life In terms of mechanical life, ion exchange materials with high wear resistance are considered preferable.

  It is preferable that the ion exchanger 90 has high hardness and good surface smoothness. In this embodiment, 0.2 mm thick Nafion (a trademark of Dupont) is used. Here, “high hardness” means that the rigidity is high and the compression elastic modulus is low. By using a material having high hardness, it becomes difficult for the processing member to follow the fine irregularities on the surface of the workpiece, such as a wafer having a wiring pattern, so that only the convex portions of the pattern are easily selectively removed. Further, “having surface smoothness” means that surface irregularities are small. That is, the ion exchanger is less likely to come into contact with a concave portion such as a wafer having a wiring pattern as a workpiece, so that only the convex portion of the pattern is easily selectively removed.

  It is more preferable to use an ion exchanger 90 having excellent water permeability. By flowing pure water or ultrapure water so as to pass through the ion exchanger 90, sufficient water is supplied to the functional group (sulfonic acid group in the case of a strongly acidic cation exchange material) that promotes the dissociation reaction of water. The amount of molecular dissociation can be increased, and the processing products (including gas) generated by the reaction with hydroxide ions (or OH radicals) can be removed by the flow of water, thereby increasing the processing efficiency. Therefore, a flow of pure water or ultrapure water is required, and the flow of pure water or ultrapure water is preferably uniform and uniform. In this way, by making the flow uniform and uniform, it is possible to achieve the uniformity and uniformity of the supply of ions and the removal of the processed product, and consequently the uniformity and uniformity of the processing efficiency.

  Such an ion exchanger 90 is comprised by the nonwoven fabric which provided the anion exchange group or the cation exchange group, for example. The cation exchanger is preferably one that bears a strongly acidic cation exchange group (sulfonic acid group), but may be one that bears a weak acid cation exchange group (carboxyl group). The anion exchanger is preferably one carrying a strong basic anion exchange group (quaternary ammonium group), but may be one carrying a weak basic anion exchange group (tertiary or lower amino group).

  Here, for example, a nonwoven fabric provided with a strongly basic anion exchange group is a so-called radiation graft polymerization method in which a polyolefin nonwoven fabric having a fiber diameter of 20 to 50 μm and a porosity of about 90% is subjected to graft polymerization after γ-ray irradiation. Thus, a graft chain is introduced, and then the introduced graft chain is aminated to introduce a quaternary ammonium group. The capacity of the ion exchange group to be introduced is determined by the amount of graft chains to be introduced. In order to perform the graft polymerization, for example, using monomers such as acrylic acid, styrene, glycidyl methacrylate, sodium styrenesulfonate, chloromethylstyrene, and the like, by controlling the monomer concentration, reaction temperature, and reaction time, The amount of grafting to be polymerized can be controlled. Therefore, the ratio of the weight after graft polymerization to the weight of the material before graft polymerization is called the graft ratio. This graft ratio can be up to 500%, and the ion exchange groups introduced after graft polymerization are A maximum of 5 meq / g is possible.

  The nonwoven fabric provided with the strongly acidic cation exchange group was irradiated with γ-rays on a polyolefin nonwoven fabric having a fiber diameter of 20 to 50 μm and a porosity of about 90%, in the same manner as the method of providing the strongly basic anion exchange group. The graft chain is introduced by a so-called radiation graft polymerization method in which post-graft polymerization is performed, and then the introduced graft chain is treated with, for example, heated sulfuric acid to introduce a sulfonic acid group. Moreover, a phosphoric acid group can be introduce | transduced if it processes with the heated phosphoric acid. Here, the graft ratio can be 500% at the maximum, and the ion exchange group introduced after the graft polymerization can be 5 meq / g at the maximum.

  Examples of the material of the ion exchanger 90 include polyolefin polymers such as polyethylene and polypropylene, and other organic polymers. Moreover, as a raw material form, a woven fabric, a sheet | seat, a porous material, a short fiber, etc. other than a nonwoven fabric are mentioned.

  Here, polyethylene and polypropylene can be subjected to graft polymerization by generating radicals in the material by first irradiating the material with radiation (γ rays and electron beams) (pre-irradiation) and then reacting with the monomer. . Thereby, a graft chain having high uniformity and few impurities can be formed. On the other hand, other organic polymers can be radically polymerized by impregnating the monomer and irradiating (simultaneously irradiating) radiation (γ rays, electron beams, ultraviolet rays). In this case, it is not uniform, but can be applied to most materials.

  In this way, by forming the ion exchanger 90 with a nonwoven fabric having anion exchange capacity or cation exchange capacity, liquid such as pure water or ultrapure water or an electrolyte solution can freely move inside the nonwoven fabric, and the nonwoven fabric It becomes possible to easily reach an active site having an internal water decomposition catalytic action, and many water molecules are dissociated into hydrogen ions and hydroxide ions. Further, since the hydroxide ions generated by the dissociation are efficiently transferred to the surface of the processing electrode as the liquid such as pure water, ultrapure water, or electrolytic solution moves, a high current can be obtained even at a low applied voltage.

  Here, when the ion exchanger 90 is composed only of an anion exchange group or a cation exchange group, not only the work material that can be electrolytically processed but also the impurities are likely to be generated depending on the polarity. Therefore, an anion exchanger having an anion exchange group and a cation exchanger having a cation exchange group are superposed, or both anion exchange groups and cation exchange groups are added to the ion exchanger 90 itself. In this case, the range of the material to be processed can be expanded, and impurities can be hardly generated.

  In this embodiment, the cathode and the anode of the power source 48 are alternately connected to the electrode 86 of the adjacent electrode member 82. For example, the electrode 86a (see FIG. 8) is connected to the cathode of the power supply 48, and the electrode 86b (see FIG. 8) is connected to the anode. For example, in the case of processing copper, an electrolytic processing action occurs on the cathode side, so that the electrode 86a connected to the cathode of the power supply 48 becomes a processing electrode, and the electrode 86b connected to the anode becomes a power supply electrode. Thus, in this embodiment, the processing electrodes and the power feeding electrodes are alternately arranged in parallel.

  Depending on the processing material, the electrode connected to the cathode of the power supply 48 may be used as a feeding electrode, and the electrode connected to the anode may be used as a processing electrode. That is, when the material to be processed is, for example, copper, molybdenum, or iron, an electrolytic processing action occurs on the cathode side. Therefore, the electrode 86a connected to the cathode of the power supply 48 becomes a processing electrode, and the electrode 86b connected to the anode supplies power. It becomes an electrode. On the other hand, when the material to be processed is, for example, aluminum or silicon, an electrolytic processing action occurs on the anode side. Therefore, the electrode 86b connected to the anode of the power supply 48 becomes a processing electrode, and the electrode 86a connected to the cathode serves as a feeding electrode. Become.

  When the workpiece is a conductive oxide such as tin oxide or indium tin oxide (ITO), electrolytic processing is performed after reducing the workpiece. That is, in FIG. 5, the electrode connected to the anode of the power supply 48 is a reduction electrode, and the electrode connected to the cathode is a power supply electrode to reduce the conductive oxide. Subsequently, the reduced conductive oxide is processed using the electrode that was previously the power supply electrode as the processing electrode. Alternatively, the reduction electrode may be a processed electrode by reversing the polarity when the conductive oxide is reduced. Also, the conductive oxide can be removed by using the workpiece as a cathode and facing the anode electrode.

  In the above example, the copper film 6 as the conductor film formed on the surface of the substrate is subjected to electrolytic processing. However, unnecessary ruthenium (Ru) deposited or adhered to the surface of the substrate. Similarly, the film can be electrolytically processed (etched away) using the ruthenium film as the anode and the electrode connected to the cathode as the processing electrode.

  As described above, the processing electrode and the feeding electrode are alternately provided in the Y direction of the electrode portion 46 (direction perpendicular to the longitudinal direction of the electrode member 82), thereby feeding power to the conductor film (workpiece) of the substrate W. There is no need to provide a power feeding section to be performed, and the entire surface of the substrate can be processed. Further, by changing the polarity of the voltage applied between the electrodes 86 in a pulse shape, the electrolytic product can be dissolved, and the flatness can be improved by the multiplicity of processing repetition.

  Here, oxidation or elution of the electrode 86 of the electrode member 82 generally causes a problem due to an electrolytic reaction. For this reason, it is preferable to use carbon, a comparatively inactive noble metal, a conductive oxide, or a conductive ceramic rather than the metal and metal compound which are widely used for an electrode as a raw material of an electrode. As an electrode made of this noble metal, for example, titanium is used as the base electrode material, platinum or iridium is attached to the surface by plating or coating, and sintering is performed at a high temperature to maintain stability and strength. Can be mentioned. Ceramic products are generally obtained by heat treatment using inorganic materials as raw materials, and products having various characteristics are made using various nonmetals, metal oxides, carbides and nitrides as raw materials. Some of these are conductive ceramics. When the electrode is oxidized, the electrical resistance value of the electrode increases, leading to an increase in applied voltage. Thus, by protecting the electrode surface with a material that is difficult to oxidize such as platinum or a conductive oxide such as iridium, the electrode is protected. A decrease in conductivity due to oxidation of the material can be prevented.

  As shown in FIG. 8, a channel 92 for supplying pure water, more preferably ultrapure water to the surface to be processed is formed inside the base 84 of the electrode unit 46. A pure water supply source (not shown) is connected via a pure water supply pipe 94. On both sides of each electrode member 82, pure water injection nozzles 96 for injecting pure water or ultrapure water supplied from the channel 92 between the substrate W and the ion exchanger 90 of the electrode member 82 are installed. ing. The pure water injection nozzle 96 has an injection port 98 for injecting pure water or ultrapure water toward a processing surface of the substrate W facing the electrode member 82, that is, a contact portion between the substrate W and the ion exchanger 90. It is provided at a plurality of locations (see FIG. 7) along the X direction. Pure water or ultrapure water in the flow path 92 is supplied from the injection port 98 of the pure water injection nozzle 96 to the entire processing surface of the substrate W. Here, as shown in FIG. 9, the height of the pure water injection nozzle 96 is lower than the height of the ion exchanger 90 of the electrode member 82, and the substrate W contacts the ion exchanger 90 of the electrode member 82. Also when it is made to do, the pure water injection nozzle 96 does not contact the substrate W.

  As shown in FIG. 9, rounded chamfered portions 102 are provided at both edge portions of each electrode member 82 facing the substrate W of the electrode 86, and the ion exchanger 90 includes the chamfered portion 102. The surface of the chamfered portion 102 is covered with a roundness along the shape. In this way, by providing the chamfered portion 102 having a rounded edge at the surface of the electrode 86 facing the substrate W, the electric field concentration generated at the edge of the surface of the electrode 86 facing the substrate W can be reduced. Thus, the lifetime of the ion exchanger 90 can be extended.

  That is, the electrode 86a connected to the cathode of the power supply 48 becomes the processing electrode in a state where the surface of the electrode 86 having no roundness at the edge portion of the surface facing the substrate W is covered with the ion exchanger 90, and the electrode connected to the anode When processing is performed by applying a predetermined voltage so that 86b becomes a power supply electrode, electric field concentration occurs at the edge portion A of the electrode 86, particularly the surface facing the substrate W, as shown in FIG. Then, processed products (copper ions and copper oxide) accumulate preferentially from the portion of the ion exchanger 90 in contact with the edge portion A of the electrode 86 where the electric field concentration occurs, resulting in a short circuit of current. The ion exchange capacity of the entire ion exchanger 90 cannot be used up. This is because when the processed product accumulates inside the ion exchanger 90 and the processed product reaches the surface to be processed and a short circuit of current occurs, the processing does not proceed or the processing uniformity cannot be maintained. It is difficult to regenerate (it is difficult to remove the precipitate by regeneration), and even if there is a margin in the ion exchange capacity of the ion exchanger 90 at this time, it must be regarded as a lifetime as an ion exchanger. This is because it is necessary to replace the exchanger.

  On the other hand, in this embodiment, by providing a chamfered portion 102 having a roundness at the edge portion of the surface facing the substrate W of the electrode 86, the electric field concentration generated in the chamfered portion 102 is reduced, and the above-mentioned The lifetime of the ion exchanger 90 can be extended by reducing local accumulation of the processed product in the ion exchanger 90.

  Further, a through hole 100 that leads from the flow path 92 to the ion exchanger 90 is formed inside the electrode 86 of each electrode member 82. With such a configuration, pure water or ultrapure water in the flow path 92 is supplied to the ion exchanger 90 through the through hole 100. Here, the pure water is, for example, water having an electric conductivity of 10 μS / cm or less, and the ultrapure water is, for example, water having an electric conductivity of 0.1 μS / cm or less. By performing electrolytic processing using pure water or ultrapure water that does not contain an electrolyte in this way, it is possible to prevent the impurities such as the electrolyte from adhering to or remaining on the surface of the substrate W. . Furthermore, since copper ions and the like dissolved by electrolysis are immediately captured by the ion exchanger 90 by an ion exchange reaction, the dissolved copper ions and the like are deposited again on other parts of the substrate W or oxidized to form fine particles. The surface of the substrate W is not contaminated.

Further, instead of pure water or ultrapure water, a liquid having an electric conductivity of 500 μS / cm or less, or an arbitrary electrolytic solution, for example, an electrolytic solution obtained by adding an electrolyte to pure water or ultrapure water may be used. By using the electrolytic solution, electric resistance can be reduced and power consumption can be reduced. As this electrolytic solution, for example, a neutral salt such as NaCl or Na ₂ SO ₄ , an acid such as HCl or H ₂ SO ₄ , or an alkali such as ammonia can be used. Depending on the characteristics, it can be appropriately selected and used.

  Furthermore, instead of pure water or ultrapure water, a surfactant or the like is added to pure water or ultrapure water, and the electric conductivity is 500 μS / cm or less, preferably 50 μS / cm or less, more preferably 0. A liquid having a specific resistance of 10 MΩ · cm or less may be used. Thus, by adding a surfactant to pure water or ultrapure water, a layer having a uniform suppressing action to prevent the movement of ions at the interface between the substrate W and the ion exchanger 90 is formed. The flatness of the work surface can be improved by reducing the concentration of ion exchange (dissolution of metal). Here, the surfactant concentration is preferably 100 ppm or less. If the value of the electrical conductivity is too high, the current efficiency is lowered and the processing speed is slowed down. However, the electrical conductivity is 500 μS / cm or less, preferably 50 μS / cm or less, more preferably 0.1 μS / cm or less. A desired processing speed can be obtained by using a liquid having

  Next, substrate processing (electrolytic processing) using the substrate processing apparatus in this embodiment will be described. First, for example, as shown in FIG. 1B, a cassette containing a substrate W on which a copper film 6 is formed as a conductor film (processed portion) on the surface is set in a load / unload unit 30. A single substrate W is taken out by the transfer robot 36. The transfer robot 36 transfers the taken out substrate W to the reversing machine 32 as necessary, and reverses the substrate W so that the surface on which the conductive film (copper film 6) is formed faces downward.

  The transfer robot 36 receives the inverted substrate W, transfers it to the electrolytic processing apparatus 34, and holds it by suction by the substrate holder 42. The arm 40 is moved to move the substrate holding portion 42 holding the substrate W to a processing position directly above the electrode portion 46. Next, the vertical movement motor 50 is driven to lower the substrate holding portion 42, and the substrate W held by the substrate holding portion 42 is brought into contact with or close to the surface of the ion exchanger 90 of the electrode portion 46. In this state, the rotation motor 58 is driven to rotate the substrate W, and at the same time, the hollow motor 60 is driven to scroll the electrode portion 46. At this time, pure water or ultrapure water is jetted between the substrate W and the electrode member 82 from the jet port 98 of the pure water jet nozzle 96, and pure water or ultrapure water is passed through the through holes 100 of the electrode portions 46. Is included in the ion exchanger 90. In this embodiment, pure water or ultrapure water supplied to the ion exchanger 90 is discharged from the longitudinal ends of the electrode members 82.

  Then, a predetermined voltage is applied so that the electrode 86a connected to the cathode of the power supply 48 serves as a processing electrode and the electrode 86b connected to the anode serves as a power supply electrode. Electrolytic processing of the conductor film (copper film 6) on the surface of the substrate W is performed at the processing electrode (cathode) by the product ions. In this embodiment, during the electrolytic processing, the reciprocating motor 56 is driven to move the arm 40 and the substrate holder 42 in the Y direction. As described above, in this embodiment, the electrode portion 46 is scrolled and processed while moving the substrate W in a direction perpendicular to the longitudinal direction of the electrode member 82. The substrate W may be scrolled while moving in a direction perpendicular to the longitudinal direction. Moreover, it is good also as replacing with a scrolling motion and performing the rectilinear reciprocating motion to a Y direction.

  As the electrolytic processing proceeds, processing products such as copper ions and copper oxides are taken in and stored in the ion exchanger 90. As described above, the electrode 86 and the substrate W are connected to each other. By providing a chamfered portion 102 with a rounded edge on the opposite surface and reducing the concentration of the electric field generated in the chamfered portion 102, local accumulation of the processed product in the ion exchanger 90 is reduced. Thus, the lifetime of the ion exchanger 90 can be extended.

  During the electrolytic machining, the voltage applied between the machining electrode and the feeding electrode or the current flowing therebetween is monitored by the monitor unit 38 to detect the end point (machining end point). That is, when electrolytic processing is performed in the state where the same voltage (current) is applied, a difference occurs in the current (applied voltage) flowing depending on the material. For example, as shown in FIG. 10 (a), when the current flowing when electrolytic processing is performed on the surface of the substrate W on which the material B and the material A are sequentially formed is monitored, the material A is electrolytically processed. While a constant current flows during the process, the current that flows at the time of transition to processing of a different material B changes. Similarly, even if the voltage is applied between the machining electrode and the feeding electrode, as shown in FIG. 10B, a constant voltage is applied while the material A is electrolytically processed. The voltage applied at the time of shifting to processing of a different material B changes. 10A shows a case where the current is less likely to flow when the material B is electrolytically processed than when the material A is electrolytically processed. FIG. 10B shows the case where the material B is electrolytically processed. Shows an example where the voltage is higher than when the material A is electrolytically processed. Thus, the end point can be reliably detected by monitoring the change in the current or voltage.

  In addition, although the monitor part 38 demonstrated the example which monitored the voltage applied between a process electrode and a feeding electrode, or the electric current which flows between this, and detected the process end point, in this monitor part 38, it is under processing. A change in the state of the substrate may be monitored to detect an arbitrarily set processing end point. In this case, the processing end point indicates a point in time when a desired processing amount is reached or a parameter having a correlation with the processing amount reaches an amount corresponding to the desired processing amount for a specified portion of the processing surface. As described above, even during the machining, the machining end point can be arbitrarily set and detected so that the electrolytic machining can be performed in a multistage process.

  After the completion of the electrolytic processing, the connection with the electrode 86 of the power supply 48 is disconnected, the rotation of the substrate holding part 42 and the electrode part 46 is stopped, and then the substrate holding part 42 is raised and the arm 40 is moved to move the substrate W. Delivered to the transfer robot 36. The transport robot 36 that has received the substrate W transports it to the reversing machine 32 and reverses it if necessary, transports it to the first cleaning machine 31a and transports the primary cleaning of the substrate to the second cleaning machine 31b. Substrate secondary cleaning (finish cleaning) is sequentially performed and dried, and the dried substrate W is returned to the cassette of the load / unload unit 30.

  Here, when using a liquid having a large resistance value such as ultrapure water, the electrical resistance can be reduced by bringing the ion exchanger 90 into contact with the substrate W, and the applied voltage is also small. Power consumption can be reduced. This “contact” does not mean “pressing” in order to apply physical energy (stress) to the workpiece as in CMP, for example. Therefore, in the present electrolytic processing apparatus in this embodiment, the vertical movement motor 50 is used for contact or proximity of the substrate W to the electrode portion 46. For example, a pressing mechanism that positively presses the substrate and the polishing member in the CMP apparatus. Is not provided. That is, in CMP, the substrate is generally pressed against the polishing surface with a pressing force of about 20 to 50 kPa. In the electrolytic processing apparatus of this embodiment, for example, the ion exchanger 90 is applied to the substrate W with a pressure of 20 kPa or less. What is necessary is just to contact, and even if it is the pressure of 10 kPa or less, a sufficient removal process effect is acquired.

  In the above example, as shown in FIG. 12A, the electrode member 82 is provided with chamfered portions 102 having rounded edges at both edges of the surface of the electrode 86 facing the substrate W. Although what was covered integrally with the ion exchanger 90 is used, you may use the electrode member shown in FIG.12 (b) and FIG.12 (c). That is, the electrode member 182 shown in FIG. 12B extends as an electrode 186 connected to the power source 48 (see FIGS. 4 and 5) in a rectangular shape with a narrow width S and a long shape. The surface of the electrode 186 is integrally covered with an ion exchanger 190. As described above, when the electrode 186 having a narrow width and extending in a long shape is used, the ion exchanger 190 covering the electrode 186 is formed by making the entire surface 188 facing the substrate W semicircular. As a result, local accumulation of processed products on the substrate can be reduced and the area of the ion exchanger 190 in contact with or close to the substrate W can be reduced.

  The electrode member 182a shown in FIG. 12 (c) uses an electrode 186a connected to the power supply 48 (see FIGS. 4 and 5) having a circular cross section and extending in a long shape. The surface of the electrode 186a Are integrally covered with an ion exchanger 190a. Also in this example, local accumulation of the processed product on the ion exchanger 190a covering the electrode 186a can be reduced, and the area of the ion exchanger 190a in contact with or close to the substrate W can be reduced.

  13 (a) to 13 (d) show the main parts of different electrode members of the electrolytic processing apparatus in still another embodiment of the present invention. That is, in the electrode member 282 shown in FIG. 13A, an insulator 292 is integrally formed on the surface of the electrode 286 connected to the power source 48 (see FIGS. 4 and 5) facing the substrate W, and this electrode 286 is formed. The surface of the insulator 292 is integrally covered with an ion exchanger 290. Chamfered portions 294 having roundness are formed at both edge portions of the surface of the insulator 292 facing the substrate W.

  Similarly to the above, when the ion exchanger 290 is disposed so as to cover the electrode 286 and a voltage is applied between the electrodes (processing electrode-feeding electrode) and processing is performed, the electrode 286 faces the surface facing the substrate W. Electric field concentration occurs, and processed products (copper ions and copper oxides) accumulate preferentially in portions of the ion exchanger 290 that are in contact with or close to the surface of the electrode 286 facing the substrate W. As in this example, by interposing the insulator 292 between the surface of the electrode 286 facing the substrate W and the ion exchanger 290, electric field concentration is eliminated on the surface of the electrode 286 facing the substrate W, and The ion exchange of the ion exchanger 290 located between the surface of the electrode 286 facing the substrate W and the substrate W is made farther from the substrate W with the surface of the electrode 286 facing the substrate W through the insulator 292. The capacity can be used up. Thereby, the lifetime of the ion exchanger 290 can be extended.

  The electrode member 282a shown in FIG. 13B has a rectangular shape with a narrow cross section as the electrode 286a connected to the power supply 48 (see FIGS. 4 and 5), as in the example shown in FIG. 12B. The insulator 292a having a semicircular top is integrally formed on the surface of the electrode 286a facing the substrate W, and the surfaces of the electrode 286a and the insulator 292a are formed. The ion exchanger 290a is integrally covered.

  The electrode member 282b shown in FIG. 13 (c) has a semicircular cross section and is long as an electrode 286b connected to the power supply 48 (see FIGS. 4 and 5), as in the example shown in FIG. 12 (c). Using an elongated one, the insulator 292b is integrally formed on the surface of the electrode 286b facing the substrate W so as to form a perfect circle between the electrode 286b and a semicircular cross section. The surfaces of the electrode 286b and the insulator 292b are integrally covered with an ion exchanger 290b.

  The electrode member 282c shown in FIG. 13 (d) uses an electrode 286c connected to the power source 48 (see FIGS. 4 and 5) having a rectangular shape with a narrow cross section and extending in a long shape. An insulator 292c having a semi-circular top is integrally formed on the surface of the 286c facing the substrate W, and the top of the insulator 292c is removed, and a region covering both sides of the electrode 286c is formed in, for example, C An ion exchanger 296 made of a membrane is arranged, and the top portion of the insulator 292b and the side of the ion exchanger 296 are integrally covered with an ion exchanger 290c made of, for example, Nafion (a trademark of Dupont). As described above, the ion exchange capacity can be increased by disposing the other ion exchanger 296 between the electrode 286c and the ion exchanger 290c in contact with the substrate W.

  In the example shown in FIGS. 13B to 13D, as in the example shown in FIG. 13A, electric field concentration is eliminated on the surface of the electrodes 286a, 286b, and 286c facing the substrate W. Further, the opposing surfaces of the electrodes 286a, 286b, and 286c facing the substrate W are separated from the substrate W via the insulators 292a, 292b, and 292c, and the opposing surfaces of the electrodes 286a, 286b, and 286c and the substrate W are separated from each other. The lifetime of the ion exchangers 290a, 290b, and 290c can be extended by using up the ion exchange capacity of the ion exchangers 290a, 290b, and 290c positioned between the ion exchangers.

  In FIGS. 13A to 13D, insulators 292, 292a, 292b, and 292c having an arbitrary height (thickness) are formed integrally with the electrodes 286, 286a, 286b, and 286c. Thus, the manufacturing process is facilitated, and the surfaces of the electrodes 286, 286a, 286b, and 286c facing the substrate W are separated from the substrate W by a desired distance via the insulators 292, 292a, 292b, and 292c. In this example, the surfaces of the electrodes 286, 286a, 286b, and 286c facing the substrate W may be covered with a highly insulating vinyl tape or the like.

  FIG. 14 shows an electrode member of a substrate processing apparatus according to still another embodiment of the present invention. In this example, as the ion exchanger 390, the first ion exchanger 390a stacked on the upper portion of the electrode 386, and the second ion exchanger that integrally covers the surfaces of the electrode 386 and the first ion exchanger 390a. (Ion exchange membrane) What is provided with 390b is used. Then, the entire periphery (that is, the electrode edge portion and the electrode side surface) excluding the central portion of the surface of the electrode 386 facing the substrate W is covered with the insulator 392, and the electrode 386 and the second ion exchanger 390b are insulated from each other. Thus, an electrode member 382 is configured.

  Here, as the first ion exchanger 390a, it is preferable to use an ion exchanger having a high ion exchange capacity. In this embodiment, the total ion exchange capacity of the ion exchanger 390 is increased by using a nonwoven fabric ion exchanger having a thickness of 1 mm. By comprising in this way, the total amount accumulate | stored in the ion exchanger 390 of the processed product (copper oxide or copper ion) generated by the electrolytic reaction can be increased.

  Further, at least the second ion exchanger 390b facing the workpiece preferably has high hardness and good surface smoothness as in the above example. In this embodiment, 0.2 mm thick Nafion (a trademark of Dupont) is used. As described above, the ion exchanger 390 is configured by combining the second ion exchanger 390b having surface smoothness and the first ion exchanger 390a having a large ion exchange capacity, so that the ion exchange capacity is small. The disadvantage of the second ion exchanger 390b can be compensated by the first ion exchanger 390a, so that the ion exchange capacity of the ion exchanger 390 as a whole can be increased.

  Here, as in this example, an ion exchanger 390 having a plurality of ion exchangers 390a and 390b is used, and as shown in FIG. When the second ion exchanger 390b is brought into contact with each other, for example, a current flows preferentially to the second ion exchanger (ion exchange membrane) 390b made of Nafion on the outside, and this ion exchanger (ion exchange membrane) 390b. In other words, the processed product accumulates intensively and locally, and the total ion exchange amount of the ion exchanger 390 including the other ion exchanger 390a cannot be used up. In particular, in the case of a thin ion exchange membrane such as Nafion, the tendency becomes remarkable because the ion exchange capacity is small.

  In this example, the electrode 386 and the second ion exchanger 390b in contact with or in proximity to the substrate W are insulated from each other via the insulator 392, and have priority over the second ion exchanger 390b in contact with or in proximity to the substrate W. By preventing the current from flowing, the effect of extending the lifetime of the entire ion exchanger 390 including the other ion exchanger 390a can be obtained.

  FIGS. 16A to 16C show different electrode members of an electrolytic processing apparatus in still another embodiment of the present invention. In the example shown in FIG. 16A, the ion exchanger 490 includes a first layer made of, for example, a C membrane (nonwoven fabric ion exchanger) having a high ion exchange capacity, in which a plurality (four layers in the drawing) are stacked on the electrode 486. A device including an ion exchanger 490a and a second ion exchanger (ion exchange membrane) 490b made of, for example, Nafion that integrally covers the electrode 486 and the plurality of first ion exchangers 490a is used. The electrode member 482 is configured by covering the entire periphery except for the central portion of the surface of the electrode 486 facing the substrate W with an insulator 492 and insulating the electrode 486 and the second ion exchanger 490b from each other.

  Thus, for example, by stacking a large number of first ion exchangers 490a made of C membranes (nonwoven cloth ion exchangers) having a high ion exchange capacity, the ion exchange capacity of the ion exchanger 490 as a whole can be further increased. it can.

  16 (b) is different from the example shown in FIG. 16 (a) in that a plurality of stacked first ion exchangers 490a are surrounded by a second insulator 492a except for the surface facing the substrate W. Thus, the electrode member 482a is configured by insulating the first ion exchanger 490a and the second ion exchanger 490b from each other via the second insulator 492a. Other configurations are substantially the same as the example shown in FIG.

In the case of using a plurality of membrane ion exchangers 490a and 490b, accumulation and growth of processed products proceed in order from the first ion exchanger 490a in contact with the electrode 486 and positioned at the lowest layer. At this time, when the outer peripheral portion of the first ion exchanger 490a located in the lowermost layer and the second exchanger 490b are in contact with each other as in the example shown in FIG. The processed product P1 accumulated in the _first ion exchanger 490a is spread from the contact toward the second ion exchanger 490b that is in contact with or close to the substrate, and the first ion exchanger 490a and the first ion exchanger 490a processed product at the interface between the second ion exchanger 490b _{P 2} accumulates. Then, the processed product P ₃ internally accumulated in the first ion exchanger 490b, leading to a short circuit.

  On the other hand, according to the example shown in FIG. 16B, the second ion exchange 490b is brought into contact with or close to the electrode member 486 and the substrate W via the insulator 492. The body 490b and the first ion exchanger 490a are insulated from each other via the second insulator 492a, so that the processed product accumulated in the first ion exchanger 490a located at the bottom layer is Without being diffused to the second ion exchanger 490b in contact with or in proximity to W, it is accumulated in the first ion exchanger 490a positioned thereon, and the processed product is accumulated in all of the first ion exchanger 490a. After that, the lifetime of the entire ion exchanger 490 can be increased by accumulating it in the second ion exchanger 490b.

  As shown in FIG. 16C, the second ion exchanger 490b in contact with or close to the electrode member 486 and the substrate W, and the second ion exchanger 490b and the first ion exchanger 490a are cylindrical. It is also possible to insulate it integrally through an insulator 492c that extends integrally.

  Although one embodiment of the present invention has been described so far, it is needless to say that the present invention is not limited to the above-described embodiment, and may be implemented in various forms within the scope of the technical idea.

It is a figure which shows one manufacture example of a copper wiring board in order of a process. The processing electrode and the feeding electrode are brought close to the substrate (workpiece), and pure water or a liquid having an electric conductivity of 500 μS / cm or less is supplied between the processing electrode and the feeding electrode and the substrate (workpiece). It is a figure attached | subjected to description of the principle of the electrolytic processing by this invention when doing. It is a top view which shows the structure of the substrate processing apparatus provided with the electrolytic processing apparatus in embodiment of this invention. It is a top view which shows the electrolytic processing apparatus of the substrate processing apparatus shown in FIG. It is a longitudinal cross-sectional view of FIG. 6A is a plan view showing a rotation prevention mechanism in the electrolytic processing apparatus of FIG. 4, and FIG. 6B is a cross-sectional view taken along line AA of FIG. 6A. It is a top view which shows the electrode part in the electrolytic processing apparatus of FIG. It is the BB sectional view taken on the line of FIG. It is the elements on larger scale of FIG. FIG. 10 (a) shows the relationship between the current flowing when electrolytic processing is performed on the surface of the substrate on which a different material is deposited, and FIG. 10 (b) shows the relationship between the applied voltage and time, respectively. It is a graph to show. It is sectional drawing which shows the electrode member which covered the surface of the electrode which does not have roundness in the edge part of the surface facing the board | substrate W with the ion exchanger as a comparative example of this invention. It is sectional drawing which shows the principal part of each different electrode member in other embodiment of this invention. It is sectional drawing which shows the principal part of each different electrode member in other embodiment of this invention. It is sectional drawing which shows the principal part of the electrode member in other embodiment of this invention. As a comparative example of the present invention, a cross-sectional view showing an electrode member in which an ion exchanger having a plurality of ion exchangers is used and an electrode and an outer ion exchanger in contact with or close to the substrate are brought into contact with each other It is. It is sectional drawing which shows the principal part of each different electrode member in other embodiment of this invention.

Explanation of symbols

6 Copper film (conductor film)
7 Seed layer 10 Workpieces 12a, 12b Ion exchanger 14 Processing electrode 16 Feed electrode 18 Ultrapure water 20 Water molecule 22 Hydroxide ion 24 Hydrogen ion 26 Reactant 30 Load / unload unit 32 Reversing machine 34 Electrolytic processing device 36 Transfer robot 38 Monitor unit 40 Arm 42 Substrate holding unit 44 Movable frame 46, 46a Electrode unit 48 Power supply 50 Motor for vertical movement 52 Ball screw 54 Ball screw 56 Motor for reciprocating motion 58 Motor for rotation 60 Hollow motor 62 Main shaft 64 Drive end 66 Rotation Prevention mechanism 68, 70 Recess 72, 74 Bearing 76, 78 Shaft body 80 Connecting member 82, 182, 182a, 282, 282a, 282b, 282c, 382, 482, 482a, 482b Electrode member 84 Base 85 Holding plate 86, 186 , 186a, 286, 286a, 286b 286c, 386, 486 Electrodes 90, 190, 190a, 290, 390, 490 Ion exchanger 92 Channel 94 Pure water supply pipe 96 Pure water injection nozzle 98 Injection port 100 Through hole 102 Chamfered portions 292, 292a, 292b, 292c, 392, 492, 492a, 492b insulator

Claims (8)

An electrode part comprising an electrode member having an electrode and an ion exchanger covering the surface of the electrode;
A holding part for holding the workpiece in contact with or close to the ion exchanger of the electrode member; and
A power source connected to the electrode of the electrode member of the electrode portion,
An electrolytic processing apparatus, wherein at least an edge portion of a surface of the electrode facing the workpiece is rounded. An electrode part comprising an electrode member having an electrode and an ion exchanger covering the surface of the electrode;
A holding part for holding the workpiece in contact with or close to the ion exchanger of the electrode member; and
A power source connected to the electrode of the electrode member of the electrode portion,
An electrolytic processing apparatus, wherein a surface of the electrode facing the workpiece is provided with an insulator covered with the ion exchanger.   The electrolytic processing apparatus according to claim 2, wherein the electrode and the insulator are integrally formed. An electrode part comprising an electrode member having an electrode and an ion exchanger covering the surface of the electrode;
A holding part for holding the workpiece in contact with or close to the ion exchanger of the electrode member; and
A power source connected to the electrode of the electrode member of the electrode portion,
The ion exchanger includes an ion exchanger in contact with or close to the workpiece and another ion exchanger, and the ion exchanger in contact with or close to the electrode and the workpiece is at least partially insulated. Electrolytic processing apparatus characterized by being insulated from each other via   5. The insulator is interposed between an edge portion of a surface of the electrode facing the workpiece and an ion exchanger in contact with or close to the workpiece. Electrolytic processing equipment.   The electrolytic processing apparatus according to claim 4, wherein the electrode and the insulator are integrally formed. An electrode part comprising an electrode member having an electrode and an ion exchanger covering the surface of the electrode;
A holding part for holding the workpiece in contact with or close to the ion exchanger of the electrode member; and
A power source connected to the electrode of the electrode member of the electrode portion,
The ion exchanger includes an ion exchanger in contact with or close to the workpiece and another ion exchanger, and the ion exchanger and other ion exchanger in contact with or close to the workpiece are at least partially The electrolytic processing apparatus is characterized in that they are insulated from each other through an insulator.   8. The electrolytic processing apparatus according to claim 7, wherein the periphery of the other ion exchanger excluding the surface facing the workpiece is integrally surrounded by the insulator.

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