KR20180110102A - Soluble copper anode, electrolytic copper plating apparatus, electrolytic copper plating method, and preservation method of acid electrolytic copper plating solution - Google Patents

Abstract

An electrolytic copper plating apparatus, an electrolytic copper plating method, and a method of preserving an acidic electrolytic copper plating liquid which can stably inhibit the generation of an anode sludge. In order to achieve this object, there is employed a soluble copper anode comprising a titanium case containing a copper material and an oxidized iridium member contacting the titanium case, as a soluble copper anode to be used for electrolytic copper plating. Here, the iridium oxide member is made of iridium oxide alone or iridium oxide composite at least on the surface thereof, so that generation of the anode sludge is suppressed and the plating property is not deteriorated.

Description

Soluble copper anode, electrolytic copper plating apparatus, electrolytic copper plating method, and preservation method of acid electrolytic copper plating solution

The present invention relates to a soluble copper anode, an electrolytic copper plating apparatus, an electrolytic copper plating method, and a method for preserving an acid electrolytic copper plating solution.

BACKGROUND ART [0002] Electrolytic copper plating is conventionally used to form a copper wiring on a printed wiring board or the like. This electrolytic copper plating has recently been used for damascene plating of wafers, and is expected to be applied to through silicon vias (TSV) and through glass vias (TGV). With regard to electrolytic copper plating, plating techniques such as via filling and through hole filling have also been established, and demand is increasing.

In the case of conducting electrolytic copper plating, there are a method of using a soluble anode made of a copper material as an anode and a method of using an insoluble anode made of platinum, titanium, iridium oxide or the like. Here, when the soluble anode is used for electrolytic copper plating, the facility is simple and easy compared with the case where electrolytic copper plating is performed using an insoluble anode, and the anode itself is comparatively inexpensive because it does not incur maintenance cost, . In addition, when electrolytic copper plating is performed using a soluble anode, the problem of plating failure due to decomposition of the additive in the plating liquid under the influence of anodic oxidation does not occur as in the case of using an insoluble anode. For this reason, it is common to use a soluble anode when performing electrolytic copper plating at present.

However, when electrolytic copper plating is carried out using a soluble anode, a large amount of anode sludge composed of metallic copper or copper oxide due to the disproportionation reaction of monovalent copper ion is generated at the time of dissolving the anode, There is a problem of deteriorating the plating characteristics of the electrode.

As to this problem, for example, as described in Patent Document 1, attempts have been made to reduce the anode sludge by a method using a medicine or a device. Specifically, in Patent Document 1, the generation of anode sludge is suppressed by adding alkenes and alkynes to an electrolytic copper plating solution using phosphorus-containing copper as an anode.

Japanese Patent No. 5659411

However, the method disclosed in Patent Document 1 is troublesome in the concentration control of the additive, and it is difficult to maintain the effect of stably suppressing the generation of the anode sludge. Further, by the addition of these additives, the dissolution of the copper anode is accelerated to raise the copper concentration in the plating solution, which causes problems such as lowered throwing power and deterioration of plating appearance.

From the above, it is an object of the present invention to provide a soluble copper anode, an electrolytic copper plating apparatus, an electrolytic copper plating method, and a method of preserving an acidic electrolytic copper plating solution which can stably suppress the generation of anode sludge.

Accordingly, as a result of intensive studies, the present inventors have accomplished the above object by adopting the following method.

Soluble copper anode according to the present invention: The soluble copper anode according to the present invention is a soluble copper anode used for electrolytic copper plating, characterized by comprising a titanium casing containing a copper material and an iridium oxide member contacted with the titanium casing do.

The soluble copper anode according to the present invention preferably has a shape of the copper material in a ball shape.

Preferably, the soluble copper anode according to the present invention is the copper ash-containing copper material.

It is preferable that the plating solution in the electrolytic copper plating using the soluble copper anode according to the present invention is an acidic electrolytic copper plating solution containing a disulfide compound.

Preferably, the soluble copper anode according to the present invention further comprises an anode bag covering the periphery of the titanium case and the iridium oxide member.

 The soluble copper anode according to the present invention preferably has an area ratio of the surface of the copper material immersed in the acidic electrolytic copper plating solution of the oxidized iridium member to 1000: 10-1000: 200.

 In the soluble copper anode according to the present invention, it is preferable that at least the surface material of the iridium oxide member is iridium oxide or iridium oxide composite.

 The soluble copper anode according to the present invention preferably has a coating containing iridium oxide or iridium oxide composite on the surface of the substrate made of any one of titanium, zirconium, stainless steel and nickel alloy.

 In the soluble copper anode according to the present invention, it is preferable that the iridium oxide composite is one in which 30 to 70% of iridium oxide, tantalum oxide, titanium oxide and platinum are mixed.

 It is preferable that the shape of the substrate is a mesh, a sheet, a tube, a plate, a line, a rod and a ball shape in the soluble copper anode according to the present invention.

 Electrolytic copper plating apparatus according to the present invention: The electrolytic copper plating apparatus according to the present invention is characterized by having the soluble copper anode described above.

 Electrolytic Copper Plating Method According to the Present Invention: The electrolytic copper plating method according to the present invention is characterized by using a direct current or a PPR current when electrolytic copper plating is performed on an object to be plated using the electrolytic copper plating apparatus described above do.

In the electrolytic copper plating method according to the present invention, it is preferable to use a printed wiring board or a wafer as the plating object.

Method of Preserving Acidic Electrolytic Copper Liquid According to the Present Invention: A method of preserving an acidic electrolytic copper plating liquid according to the present invention is a method of preserving an acidic electrolytic copper plating liquid immersed in a soluble copper anode containing a titanium case containing a copper material And the iridium oxide member is brought into contact with the titanium case at least during electrolytic stoppage.

According to the soluble copper anode, the electrolytic copper plating apparatus, the electrolytic copper plating method, and the method of preserving the acidic electrolytic copper plating solution according to the present invention, the generation of the anode sludge can be effectively suppressed, so that the plating property can be stably improved have. Further, according to the preservation method of the acidic electrolytic copper plating solution according to the present invention, the dissolution of the copper material of the soluble copper anode can be suppressed even during the electrolytic stoppage, so that the generation of the anode sludge can be effectively suppressed.

1 is a schematic cross-sectional view illustrating a case where a soluble copper anode according to the present invention is used in an electrolytic copper plating apparatus.
Fig. 2 is a cross-sectional view illustrating a via filling state in the first embodiment. Fig.
3 is a cross-sectional view illustrating a via filling state in the second embodiment.
4 is a cross-sectional photograph illustrating the via filling state in the third embodiment.
5 is a cross-sectional view illustrating the via filling state in the fourth embodiment.
6 is a cross-sectional photograph illustrating the via filling state in the fifth embodiment.
FIG. 7 is a cross-sectional view illustrating a via filling state in the sixth embodiment. FIG.
8 is a cross-sectional photograph illustrating the via filling state in Comparative Example 1. Fig.
9 is a cross-sectional photograph illustrating the via filling state in Comparative Example 2. Fig.
10 is a cross-sectional photograph illustrating the via filling state in Comparative Example 3. Fig.

Hereinafter, a method of preserving a soluble copper anode, an electrolytic copper plating apparatus, an electrolytic copper plating method, and an acidic electrolytic copper plating solution according to the present invention will be described with reference to the drawings. 1 is a schematic cross-sectional view illustrating a case where a soluble copper anode according to the present invention is used in an electrolytic copper plating apparatus.

An electrolytic copper plating apparatus according to the present invention comprises a soluble copper anode according to the present invention. The soluble copper anode is used for electrolytic copper plating and is characterized in that it includes a titanium case 3 containing a copper material 2 and an oxidized iridium member 4 brought into contact with the titanium case 3. Hereinafter, these configurations will be described.

The copper material 2 constituting the soluble copper positive electrode 1 employing the soluble copper positive electrode according to the present invention is used for generating copper ions during electrolysis to coat the surface of the plated member 20 with copper plating do. The copper material 2 is preferably in a ball shape. Since the shape of the copper material 2 is a ball shape, the surface area of the copper anode can be maximized, and more copper ions can be generated at the time of electrolysis to further enhance the plating efficiency.

Further, the copper material 2 constituting the soluble copper anode according to the present invention is preferably phosphorus-containing copper material. By using a phosphorus-containing copper member on the soluble copper anode, a coating of a compound called " black film " Cu ₂ P is formed on the surface of the phosphorus-containing copper member during electrolysis to suppress the generation of monovalent copper ions, The occurrence of sludge can be suppressed. In order to further suppress the generation of the anode sludge of the phosphorus-containing copper member, the phosphorus content is preferably set to about 0.02% to 0.06%. Use of the phosphorus-containing copper member in the soluble copper anode 1 is advantageous in that copper dissolution during electrolysis can be performed smoothly.

The titanium case 3 constituting the soluble copper anode according to the present invention may be of any shape that can hold the copper material 2 in the state in which the copper material 2 is immersed in the plating liquid 11. For example, (Mesh shape or the like) may be used. The length of the titanium case 3 is related to the surface area of the copper material 2 to be accommodated. For example, when electrolytic copper plating is performed on the surface of a standard substrate (1.0 m x 1.0 m) at a mass production site, a titanium case of about 60 mm x (1100 to 1300 mm) is used. Regarding the length and the number of the titanium cases 3, the current density of the cathode and the anode to be used and the film thickness distribution of the copper plating coated on the surface of the plating target 20 are considered. The titanium case 3 in the present invention can be a general-purpose one, and is not particularly limited.

The iridium oxide member (4) constituting the soluble copper anode according to the present invention is preferably at least a surface material of iridium oxide or iridium oxide complex. The provision of the oxidized iridium member (4) having such a constitution in the soluble copper anode prevents the generation of the anode sludge and does not cause deterioration of the plating property. Here, the iridium oxide member 4 may be made of a coating containing iridium oxide on the surface of any one of titanium, zirconium, stainless steel and nickel alloy. The base material of the iridium oxide member 4 is preferably a material which is not dissolved by electrolysis like the above-described material. It is preferable that the iridium oxide composite contains 30% to 70% of iridium oxide, one or more of tantalum oxide, titanium oxide and platinum. By providing a coating made of such an iridium oxide composite, durability as an electrode and oxygen generating effect can be greatly improved.

In the soluble copper anode according to the present invention, the base material of the iridium oxide member 4 is preferably any one of a mesh, a sheet, a tube, a plate, a wire, a rod and a ball. The size of the iridium oxide member 4 is preferably the length of the titanium case to be used except for the ball shape in consideration of suppressing the generation of the anode sludge. The iridium oxide member 4 is a shape and dimension that efficiently generates a small amount of oxygen without interfering with the dissolving of the soluble copper anode during electrolysis, so that monovalent copper ions generated in the vicinity of the iridium oxide member 4 are instantaneously To convert it into a divalent copper ion, so that generation of anode sludge can be suppressed.

It is further preferable that the soluble copper anode according to the present invention further comprises an anode bag 5 covering the periphery of the titanium case 3 and the iridium oxide member 4. [ The soluble copper anode is further provided with the anode bag 5 so that the copper material 2 contained in the titanium case 3 is stably maintained in an oxidizing atmosphere and monovalent copper ions which are the cause of the sludge, Ions can be effectively converted. Further, the soluble copper anode includes the anode bag 5, thereby preventing the formed anode sludge from diffusing into the plating liquid 11, thereby preventing deterioration of the plating characteristics. On the other hand, the anode bag 5 can be a general-purpose one, and the shape and materials are not particularly limited.

An acidic copper plating solution is used for the plating solution 11 used in the electrolytic copper plating apparatus according to the present invention. Usually, as the acidic copper plating solution 11, a copper sulfate plating solution composed of copper sulfate · 5 sulfate, sulfuric acid, chloride ions and additives is used. For example, the composition of the acidic copper plating solution 11 can be used in the range of 30 g / L to 250 g / L of copper sulfate · 5 sulfate, 30 g / L to 250 g / L of sulfuric acid and 30 mg / L to 75 mg / L of chloride ion . The temperature of the acidic copper plating solution 11 is usually in the range of 15 캜 to 60 캜, preferably 25 캜 to 35 캜. Precipitation of both copper sulfate and 5 hydrate may be precipitated on the copper anode due to an increase in sulfate concentration or an increase in sulfuric acid concentration.

Here, the acidic copper plating solution 11 used in the electrolytic copper plating apparatus according to the present invention preferably contains a disulfide compound. In recent years, when electrolytic copper plating is performed, for example, bis (3-sulfopropyl) disulfide (hereinafter simply referred to as "SPS") is used as a brightener component. However, in this case, since SPS is changed to 3-mercaptopropane-1-sulfonic acid (hereinafter simply referred to as " MPS "), in a through-hole bath, poor throwing power, poor plating appearance, There arises a problem that the appearance of one plating is defective. Especially, when the acidic copper plating solution 11 was left to stand by electrolysis, it was confirmed that SPS was reduced in the vicinity of the positive electrode to generate MPS. The generation of the MPS may cause the generation of the anode sludge composed of the MPS-Cu ⁺ complex. However, when the soluble copper anode (1) according to the present invention is used, generation of MPS due to decomposition of SPS is prevented, thereby suppressing the generation of anode sludge and eliminating adverse effects of MPS. Do not.

As described above, when the soluble copper anode 1 having the anode bag 5 is used, a very high concentration of MPS can be present in the anode bag 5. Therefore, the electrolytic solution of the iridium oxide member 4 is brought into contact with the titanium case 3 filled with the copper material 2 and electrolyzed, whereby the MPS can be detoxified very efficiently.

From the viewpoint of inhibiting the generation of MPS, it is preferable that the area ratio of the surface immersed in the acidic electrolytic copper plating solution 11 of the copper material 2 and the iridium oxide member 4 is 1000: 10 to 1000: 200. If the area ratio of the surface immersed in the acidic electrolytic copper plating solution 11 of the copper material 2 and the oxidized iridium member 4 is less than 1000: 10, oxygen generation from the surface of the iridium oxide member 4 is very small. Can not be effectively suppressed. If the area ratio exceeds 1000: 200, the generation of oxygen from the surface of the iridium oxide member 4 remarkably increases, so that the additive in the plating liquid 11 is oxidized and decomposed to increase the consumed amount of the additive. Therefore, the area ratio is more preferably 1000: 50 to 1000: 100, and still more preferably 1000: 75 to 1000: 125. On the other hand, if necessary, it may be masked by silicone rubber or the like in order to adjust the surface area immersed in the acidic electrolytic copper plating solution 11 of the iridium oxide member 4.

Further, in the electrolytic copper plating apparatus according to the present invention, it is preferable that the applicable cathode current density is in a range using a phosphorus-containing copper member normally used for plating the printed circuit board. Specifically, the cathode current density is about 0.1 A / dm ² to 10 A / dm ² , preferably 0.5 A / dm ² to 6 A / dm ² , and more preferably 1 A / dm ² to 5 A / dm ² . The anode current density is usually from 0.1 A / dm ² to 3 A / dm ² , but more preferably from 1 A / dm ² to 3 A / dm ² . The copper concentration in the acidic copper plating solution 11 tends to rise when the anode current density is too low and tends to decrease when the anode current density is too high, so that the anode area needs to be adjusted in accordance with the cathode current density used .

Here, effects obtained when the soluble copper anode according to the present invention is used and when electrolysis is stopped and electrolysis is described. When the electrolytic solution is stopped and the acidic copper plating solution 11 is left standing, the copper material 2 is dissolved by contact corrosion with the titanium case 3 to form a solution It happens. In the case where the acidic copper plating solution 11 contains a disulfide compound, SPS is reduced as shown by the formula (3) in the following formula (1) to generate MPS. Therefore, the MPS concentration in the acidic copper plating solution 11 is increased. The resulting MPS is partially oxidized and converted to SPS as shown by the following formula (4). However, the Cu (I) MPS combined with the monovalent copper ion becomes MPS as shown in the following formula (5).

The dissolvable copper anode according to the present invention is a titanium case containing a copper material (2), and the copper material (2) 3 is brought into contact with the iridium oxide member 4 so that the corrosion potential of the copper material 2 can be made to fall within the copper material 2 when it is brought into contact with the titanium case 3 and indirectly brought into contact with the iridium oxide member 4, It is possible to suppress the dissolution of the copper material 2 into the acidic electrolytic copper plating solution 11. [ As a result, the dissolution of the copper material 2 during the electrolytic stop can be suppressed and the generation of MPS can be suppressed.

When the electrolytic solution is used, the oxidized iridium member 4 of the present invention is brought into contact with the titanium case 3 to generate oxygen of the generator that is higher in activity than the surface of the iridium oxide member 4 during electrolysis, ) Is converted into an oxidizing atmosphere and monovalent copper ions are converted into divalent copper ions to suppress generation of anode sludge composed of CuCl, Cu ₂ O, and the like.

From the above, the electrolytic copper plating apparatus according to the present invention has the soluble copper anode 1 according to the present invention, so that a high quality plating film can be formed at a low cost while improving the plating efficiency.

The electrolytic copper plating method according to the present invention is characterized by using a direct current or a pulse periodic reverse (PPR) current when electrolytic copper plating is performed on the object to be plated 20 by using the electrolytic copper plating apparatus described above do.

In the copper plating method according to the present invention, when a direct current is used to conduct the electrolytic copper plating treatment on the object to be plated 20, generally used conditions can be suitably employed. For example, when a direct current is used when carrying out the electrolytic copper plating process, a direct current power source which can obtain a constant stable current value can be used. As a means for obtaining a direct current, a three-phase full-wave rectifier (ripple of 5% or less) can be used.

Further, in the copper plating method according to the present invention, a PPR current may be used when electrolytic copper plating treatment is applied to the object 20 to be plated. Here, "PPR current" refers to a current in which the direction of current is periodically changed to a pulse waveform so as to repeat electrostatic electrolysis (electrolysis for depositing plating) and reverse electrolysis in a short cycle. According to the PPR current, since a high resistance overvoltage which can not be obtained with a direct current can be obtained, a high plating throwing performance can be ensured. Therefore, it is most suitable for filling a through hole substrate having a Gauss spectrum ratio (plate thickness / hole diameter) or a via hole having a small hole diameter. When the PPR current is used, the period of the current can be arbitrarily set, but it is preferable that the electrostatic charge time is longer than the reversal charge time. For example, the electrostatic charge time is preferably 0.1 msec to 50 msec, and more preferably 1 msec to 20 msec. The inversion time is preferably 0.1 msec to 5 msec, and more preferably 0.5 msec to 2 msec.

Further, in the copper plating method according to the present invention, it is preferable to use a printed wiring board or a wafer as the plating object 20 described above. In general, the printed wiring board is electrically connected to the interlayer by a through hole and a blind via hole (BVH). This through hole is generally used as a through hole diameter of 0.15 mm to 2.8 mm and a plate thickness of 0.6 mm to 3.2 mm, for example. The blind via hole generally has a via diameter of about 20 占 퐉 to 200 占 퐉 and a depth of about 10 占 퐉 to 100 占 퐉. In the semiconductor wafer, a damascene process is employed in which a copper wiring having excellent conductivity is formed by copper sulfate plating. This process is to fill the submicron vias and trenches on the semiconductor wafer by copper sulfate plating. In these stable via filling, suppression of the formation of MPS by decomposition of SPS used as a brightener component is required. However, according to the copper plating method of the present invention, such deterioration of SPS can be effectively suppressed.

A method of preserving an acidic electrolytic copper plating solution according to the present invention is a method of preserving an acidic electrolytic copper plating solution 11 in which a soluble copper anode 1 containing a titanium case 3 containing a copper material 2 therein is immersed , Characterized in that the titanium oxide (3) is brought into contact with the iridium oxide member (4) during at least electrolytic stoppage. The iridium oxide member 4 is brought into contact with the titanium case 3 at least during electrolytic stop so that generation of monovalent copper ions during the electrolytic stoppage and generation of MPS when SPS is used in the plating solution can be suppressed have. Therefore, according to the method of preserving the acidic electrolytic copper plating solution according to the present invention, even when the electrolytic solution is started using the acidic copper plating solution 11 which has been left for a long time as it is, the appearance of the plating appearance is poor and maintenance is unnecessary.

While the present invention has been described in detail with reference to the preferred embodiments of the invention, it will be understood by those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention. do. On the other hand, the present invention is not limited to these examples.

Example 1

In Example 1, a test was conducted to confirm the filling state of vias when electrolytic copper plating was performed in a state that the iridium oxide member was in contact with the titanium case filled with the phosphorus-containing copper anode. Hereinafter, a description will be given with reference to Fig.

In this Embodiment 1, a plated member (printed substrate) 20 having a plate thickness of 1.0 mm, a via diameter of 100 m and a depth of 80 m is subjected to a desmear treatment by a MELT plate MLB-6001 process (manufactured by Meltex Co., Ltd.) . Subsequently, electroless copper plating was carried out by a Melpet CU-390 process (manufactured by Meltex Co., Ltd.). The printed board 20 was degreased, washed with water, treated with 10% sulfuric acid, and rinsed with MELPHIL CL-1000S (manufactured by Meltex Co., Ltd.), and electrolytic copper plating was performed under the following conditions.

The acidic copper plating solution 11 used in Example 1 was a solution prepared by dissolving 0.5 g of LUCENT CAPER SVF-A (manufactured by Meltex Co., Ltd., disulfide type) in a plating solution containing 220 g / L of copper sulfate · 5 hydrate, 220 g / L of sulfuric acid, 1.5 mL of a via lysing bath prepared by adding 20 mL / L of LUCENT CAPER SVF-B (Meltex Co., Ltd.) and 15 mL / L of LUCENT CAPER SVF-L (Meltex Co., Ltd.) was used. In the plating tank 10, the soluble copper anode 1 was placed in a state of being immersed in the vias laden bath 11 accommodated therein. The soluble copper anode 1 was made of an iridium oxide member (iridium oxide-coated rod (5 mm x 1.5 mm x 3 mm)) was attached to a titanium case (30 mm x 150 mm) 3 in which a copper (5 phosphorus- 100 mm) (4). Further, an anode bag 5 covering the periphery of the titanium case 3 and the iridium oxide member 4 was further provided. On the other hand, although different from the structure shown in Fig. 1, in Example 1, two sets of the soluble copper positive electrode 1 were immersed.

In Example 1, the area ratio of the surface immersed in the acidic electrolytic copper plating solution 11 of the copper material 2 and the iridium oxide member 4 was 1000: 100. Further, the printed board 20 on which 5 mm x 130 mm of electroless copper plating was applied as a negative electrode was immersed in the acidic copper plating solution 11 so as to be ¹ dm ² . This was electrolyzed at a current density of 2 A / dm ² until the electrolysis amount reached 5 AH / L, and then left overnight. After the electrolysis and left overnight, the additive was analyzed and adjusted by the CVS method using a plating solution, and was plated in a thickness of 15 탆 at ^{2 A} / dm ² . After plating, the filling conditions in the vias were observed by a cross-section method.

Fig. 2 shows a cross-sectional photograph of the via filling state in Example 1. Fig. Here, FIG. 2 (a) shows a cross-sectional photograph when electrolysis was carried out until the electrolysis amount reached 5 AH / L. Fig. 2 (b) is a cross-sectional photograph of a case where electrolytic copper plating is carried out again using a plating solution after left overnight after electrolysis. 2 (a) and 2 (b), the via filling conditions in Example 1 were as follows: electrolytic copper plating was carried out using electrolytic plating until the electrolytic amount reached 5 AH / L, When we did, there was no particular change. Table 1 shows the evaluation results of Example 1.

Example 2

In Example 2, as in Example 1, a test was conducted to confirm the via filling state in the case where the electrolytic copper plating was performed in the state that the iridium oxide member was in contact with the titanium case filled with the phosphorus-containing copper anode.

In the second embodiment, the same plating member 20 as in the first embodiment is used. In Example 2, the same treatment as in Example 1 was conducted under the same conditions as before electrolytic copper plating. Then, electrolytic copper plating was performed under the following conditions.

The acidic copper plating solution 11 used in Example 2 was a solution prepared by dissolving 0.5 g of LUCENT CAPHER HCS-A (disulfide (trade name) manufactured by Meltex Co., Ltd.) in a plating solution containing 150 g / L of copper sulfate · 5 hydrate, 150 g / L of sulfuric acid, 1.5 L of a half-lysing bath for flexible substrates was prepared by adding 15 mL / L of LUCENT CAPER HCS-B (manufactured by Meltex Co., Ltd.) and 6 mL / L of Lucentcopher HCS-L (manufactured by Meltex Co., Respectively. Then, the soluble copper anode 1 was placed in the plating bath 10 in a state of being immersed in the half-fill bath 11 for flexible substrate accommodated therein. The soluble copper anode (1) used here was the same as that of Example 1.

In Example 2, the area ratio of the surface immersed in the acidic electrolytic copper plating solution 11 of the copper material 2 and the iridium oxide member 4 was 1000: 100, which was the same as that in Example 1. In the same manner as in Example 1, the printed board 20 on which 5 mm x 130 mm of electroless copper plating was applied as the negative electrode was immersed in the acidic copper plating solution 11 so as to be ¹ dm ² . This was electrolyzed at a current density of 3 A / dm ² until the electrolysis amount reached 5 AH / L, and then left overnight. The additive was analyzed and adjusted by the CVS method using the plating solution after left for one night after electrolysis, and was plated with 15 탆 at 3 A / dm ² . After plating, the filling state of the wife was observed by cross-section method.

3 is a cross-sectional photograph of the via filling state in the second embodiment. Here, FIG. 3 (a) shows a cross-sectional photograph when electrolysis was conducted until the electrolysis amount reached 5 A / L. Fig. 3 (b) is a cross-sectional photograph of the electrolytic copper plating process using the plating solution after left overnight after electrolysis. 3 (a) and 3 (b), the via filling state in Example 2 was electrolytic copper plating using a plating solution when electrolysis was carried out until the electrolysis amount became 5 AH / L and after the plating solution was left overnight after electrolysis There was no change in particular. Table 1 shows the evaluation results of Example 2.

Example 3

In Example 3, as in Example 1, a test was conducted to confirm the via filling state when electrolytic copper plating was performed in a state in which the iridium oxide member was in contact with the titanium case filled with the phosphorus-containing copper anode.

In the third embodiment, the same plating member 20 as in the first embodiment is used. In Example 3, the same treatment as in Example 1 was conducted under the same conditions before conducting electrolytic copper plating. Then, electrolytic copper plating was performed under the following conditions.

The acidic copper plating solution 11 used in Example 3 was the same as that used in Example 1. The soluble copper anode 1 used in Example 3 was the same as Example 1 except that a plate (20 mm x 120 mm x 1 mm) coated with iridium oxide was used as the iridium oxide member 4 Respectively.

In Example 3, the area ratio of the surface immersed in the acidic electrolytic copper plating solution 11 of the copper material 2 and the iridium oxide member 4 was 1000: 200. Then, similarly to Example 1, the printed board 20 on which 5 mm x 130 mm of electroless copper plating was applied as the negative electrode was immersed in the acidic copper plating solution 11 so as to be 1 dm ² . This was electrolyzed under the same conditions as in Example 1, and after plating, the fill state of the cavity was observed by a cross-section method.

4 is a cross-sectional photograph of the via filling state in the third embodiment. Here, FIG. 4 (a) shows a cross-sectional photograph when electrolysis was conducted until the electrolysis amount reached 5 A / L. 4 (b) is a cross-sectional photograph of the electrolytic copper plating process using the plating solution after left overnight after electrolysis. 4A and 4B, the via filled state in Example 3 was evaluated by electrolytic copper plating using electrolytic plating until the electrolytic amount reached 5 AH / L and electrolytic plating overnight. When it did, there was no change in particular. Table 1 shows the evaluation results of Example 3.

Example 4

In Example 4, as in Example 1, a test was conducted to confirm the via filling state in the case where the electrolytic copper plating was performed in the state that the iridium oxide member was in contact with the titanium case filled with the phosphorus-containing copper anode.

In the fourth embodiment, the same plating member 20 as in the first embodiment is used. In Example 4, the same treatment as in Example 1 was performed under the same conditions before conducting electrolytic copper plating. Then, electrolytic copper plating was performed under the following conditions.

The same acidic copper plating solution 11 as used in Example 4 was used. The soluble copper anode 1 used in Example 4 was the same as Example 1 except that a line (1 mm x 120 mm) coated with IrO ₂ -Pt (0.3) as the iridium oxide member 4 was used Were used.

In Example 4, the area ratio of the surface immersed in the acidic electrolytic copper plating solution 11 of the copper material 2 and the iridium oxide member 4 was 1000: 10. Then, in the same manner as in Example 1, the printed board 20 on which 5 mm x 130 mm of electroless copper plating was applied as the negative electrode was immersed in the acidic copper plating solution 11 so as to be ¹ dm ² . This was electrolyzed under the same conditions as in Example 1, and after plating, the filling state in the via was observed by a cross section method.

5 shows a cross-sectional photograph of the via filling state in the fourth embodiment. Here, FIG. 5 (a) shows a cross-sectional photograph of the electrolytic solution when it was electrolyzed until it reached 5 AH / L. Fig. 5 (b) is a cross-sectional photograph of the electrolytic copper plating process using the plating solution after left overnight after electrolysis. 5A and 5B, the via filling state in Example 4 was electrolytic copper plating using the plating solution when electrolysis was carried out until the electrolysis amount became 5AH / L and after the plating solution was left overnight after electrolysis There was no change in particular. Table 1 shows the evaluation results of Example 4.

Example 5

In Example 5, as in Example 1, a test was conducted to confirm the filling state of vias in the case where electrolytic copper plating was carried out with the iridium oxide member in contact with the titanium case filled with the phosphorus-containing copper anode.

In the fifth embodiment, the same plating member 20 as in the first embodiment is used. In Example 5, the same treatment as in Example 1 was performed under the same conditions before electrolytic copper plating. Then, electrolytic copper plating was performed under the following conditions.

The same acidic copper plating solution 11 as used in Example 5 was used. The soluble copper anode 1 used in Example 5 was the same as Example 1 except that a plate (10 mm x 120 mm x 1 mm) coated with IrO ₂ -TiO ₂ (0.7) as the iridium oxide member 4 was used. The same configuration was used.

In Example 5, the area ratio of the surface immersed in the acidic electrolytic copper plating solution 11 of the copper material 2 and the iridium oxide member 4 was 1000: 100, which was the same as that in Example 1. In the same manner as in Example 1, the printed board 20 on which 5 mm x 130 mm of electroless copper plating was applied as the negative electrode was immersed in the acidic copper plating solution 11 so as to be ¹ dm ² . This was electrolyzed under the same conditions as in Example 1, and after plating, the filling state in the via was observed by a cross section method.

6 is a cross-sectional photograph of the via filling state in the fifth embodiment. Here, FIG. 6 (a) shows a cross-sectional photograph when electrolysis was carried out until the electrolysis amount became 5 AH / L. FIG. 6 (b) is a cross-sectional photograph of a case where electrolytic copper plating is performed again using a plating solution after left overnight after electrolysis. 6A and 6B, the via filling state in Example 5 is the same as in Example 5 except that the electrolytic copper electrolytic copper plating was carried out by electrolytic copper electrolysis using electrolytic electrolysis until the electrolytic amount reached 5 AH / L, When it did, there was no change in particular. Table 1 shows the evaluation results of Example 5.

Example 6

In Example 6, as in Example 1, a test was conducted to confirm the via filling state in the case where the electrolytic copper plating was performed in the state that the iridium oxide member was in contact with the titanium case filled with the phosphorus-containing copper anode.

In the sixth embodiment, the same plating member 20 as that in the first embodiment is used. In Example 6, the same treatment as in Example 1 was conducted under the same conditions before electrolytic copper plating. Then, electrolytic copper plating was performed under the following conditions.

The same acidic copper plating solution 11 as used in Example 6 was used. The dissolvable copper anode 1 used in Example 6 was prepared in the same manner as Example 1 except that a plate (5 mm x 100 mm x 1 mm) coated with IrO ₂ -Ta ₂ O ₅ (0.3) as the iridium oxide member 4 was used The same structure as in Example 1 was used.

In Example 6, the area ratio of the surface immersed in the acidic electrolytic copper plating solution 11 of the copper material 2 and the iridium oxide member 4 was 1000: 50. In the same manner as in Example 1, the printed board 20 on which 5 mm x 130 mm of electroless copper plating was applied as the negative electrode was immersed in the acidic copper plating solution 11 so as to be ¹ dm ² . This was electrolyzed under the same conditions as in Example 1, and after plating, the filling state in the via was observed by a cross section method.

7 shows a cross-sectional photograph of the via filling state in the sixth embodiment. Here, FIG. 7 (a) shows a cross-sectional photograph of the electrolytic solution when it was electrolyzed until the electrolytic amount became 5 AH / L. Fig. 7 (b) is a cross-sectional photograph showing electrolytic copper plating using a plating solution after left overnight after electrolysis. 7A and 7B, electrolytic copper plating is carried out again using the plating solution when electrolysis is performed until the electrolysis amount reaches 5 AH / L and after the electrolytic solution is left overnight after electrolysis, When it did, there was no change in particular. Table 1 shows the evaluation results of Example 6.

[Comparative Example 1]

In Comparative Example 1, a test was carried out to confirm the via filling state in the case where the titanium case filled with the phosphorus-containing copper anode was subjected to electrolytic copper plating in a state in which the iridium oxide member was not brought into contact with the titanium case.

In Comparative Example 1, the test was performed under the same conditions as in Example 1 except that the titanium case filled with the phosphorus-containing copper anode was subjected to electrolytic copper plating in a state in which the iridium oxide member was not brought into contact with the titanium case. .

 8 is a cross-sectional photograph of a via filling state in Comparative Example 1. Fig. Here, FIG. 8 (a) shows a cross-sectional photograph when electrolysis was carried out until the electrolysis amount reached 5 A / L. 8 (b) is a cross-sectional photograph of a case where electrolytic copper plating is performed again using a plating solution after left overnight after electrolysis. 8A and 8B, the via filling state in Comparative Example 1 is the same as that in the case where electrolytic water is electrolyzed until the electrolytic amount reaches 5AH / L, and electrolytic copper plating The charge condition of the via was remarkably deteriorated. Table 1 shows the evaluation results of Comparative Example 1.

[Comparative Example 2]

In Comparative Example 2, as in Comparative Example 1, a test was performed to confirm the via filling state in the case where electrolytic copper plating was performed in a state that the iridium oxide member was not brought into contact with the titanium case filled with the phosphorus-containing copper anode.

In Comparative Example 2, the test was carried out under the same conditions as in Example 2 except that the titanium case filled with the phosphorus-containing copper anode was subjected to electrolytic copper plating in a state in which the iridium oxide member was not brought into contact with the titanium case. .

9 is a cross-sectional photograph of the via filling state in Comparative Example 2. Fig. Here, FIG. 9 (a) shows a cross-sectional photograph of the electrolytic solution when it was electrolyzed until it reached 5 AH / L. Fig. 9 (b) shows a cross-sectional photograph of the electrolytic copper plating process using the plating solution after left overnight after electrolysis. 9A and 9B, the via filling state in Comparative Example 2 is the same as that in the electrolytic copper electrolytic copper plating solution obtained by electrolytic copper plating The charge condition of the via was remarkably deteriorated. Table 1 shows the evaluation results of Comparative Example 2.

[Comparative Example 3]

In Comparative Example 3, as in Comparative Example 1, a test was conducted to confirm the filling state of vias in the case where electrolytic copper plating was performed without contacting the iridium oxide member with the titanium case filled with the phosphorus-containing copper anode.

In Comparative Example 3, except that the titanium case filled with the phosphorus-containing copper anode was not contacted with the iridium oxide member, and electrolytic copper plating was performed by adding 5 g / L of maleic acid to the via-hole bath described in Japanese Patent Registration No. 5659411 Since the test was carried out under the same conditions as in Example 1, the description thereof is omitted here.

Fig. 10 shows a cross-sectional photograph of the via filling state in Comparative Example 3. Fig. Here, FIG. 7 (a) shows a cross-sectional photograph of the electrolytic solution when it was electrolyzed until the electrolytic amount became 5 AH / L. Fig. 7 (b) is a cross-sectional photograph showing electrolytic copper plating using a plating solution after left overnight after electrolysis. 7A and 7B, the via filling state in Comparative Example 3 is the same as that in the electrolytic copper electrolytic copper plating bath in which electrolytic copper is electrolyzed again using a plating solution after left overnight after electrolysis, When the plating was performed, the charging condition of the via was remarkably deteriorated. The evaluation results obtained in Comparative Example 3 are shown in Table 1.

From the above results, it is possible to suppress the dissolution of the copper material during electrolysis stop and suppress the generation of MPS by making the soluble copper anode used for the electrolytic copper plating to contact the titanium case containing the copper material with the oxidized iridium member And it was found. Thus, when electrolytic copper plating is performed using a soluble copper anode having a structure in which an iridium oxide member is brought into contact with a titanium case containing a copper material, generation of anode sludge can be suppressed and adverse effects of MPS can be effectively eliminated I can understand.

According to the soluble copper anode, the electrolytic copper plating apparatus, the electrolytic copper plating method, and the method of preserving the acidic electrolytic copper plating solution according to the present invention, the generation of the anode sludge can be stably suppressed. Further, since the soluble copper anode according to the present invention can be used by attaching it to a structure formed by housing a phosphorus-containing copper ball in a titanium case, which is conventionally used, it is economical to introduce a new facility.

1: soluble copper anode 2: copper
3: titanium case 4: absence of iridium oxide
5: Anode bag 10: Plating tank
11: plating solution (acidic copper plating solution) 20: plating member (plating object)

Claims (14)

As a soluble copper anode used for electrolytic copper plating,
A titanium case housing a copper material, and an oxidized iridium member contacting the titanium case. The method according to claim 1,
Wherein the shape of the copper material is a ball shape. 3. The method according to claim 1 or 2,
Wherein the copper-based copper-containing copper material is copper-containing phosphorus-containing copper material. 4. The method according to any one of claims 1 to 3,
Wherein the plating solution used for the electrolytic copper plating is an acidic electrolytic copper plating solution containing a disulfide compound. 5. The method according to any one of claims 1 to 4,
And an anode bag covering the periphery of the titanium case and the oxidized iridium member. 6. The method according to any one of claims 1 to 5,
Wherein an area ratio of the surface of the copper material and the surface immersed in the acidic electrolytic copper plating solution of the oxidized iridium member is 1000: 10 to 1000: 200. 7. The method according to any one of claims 1 to 6,
Wherein the oxidized iridium member is at least a surface material of an iridium oxide or iridium oxide complex. 8. The method of claim 7,
The above-mentioned iridium oxide member is provided with a coating containing iridium oxide or iridium oxide complex on the surface of a substrate made of any one of titanium, zirconium, stainless steel and nickel alloy. 9. The method according to claim 7 or 8,
Wherein the iridium oxide composite is characterized in that 30 to 70% of one or more materials selected from the group consisting of tantalum oxide, titanium oxide and platinum is mixed with iridium oxide. 10. The method according to claim 8 or 9,
Wherein the shape of the substrate is one of a mesh, a sheet, a tube, a plate, a line, a rod and a ball shape. An electrolytic copper plating apparatus characterized by comprising the soluble copper anode according to any one of claims 1 to 10. 11. An electrolytic copper plating apparatus according to claim 11,
Wherein a direct current or a PPR current is used when electrolytic copper plating is performed on the object to be plated. 13. The method of claim 12,
Wherein the object to be plated is a printed wiring board or a wafer. A method for preserving an acidic electrolytic copper plating solution immersed in a soluble copper anode comprising a titanium casing containing a copper material,
Wherein the titanium case is brought into contact with the iridium oxide member during at least electrolytic stoppage of the acidic electrolytic copper plating solution.

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