Chemical polishing liquid and surface treatment method for surface treatment of copper or copper alloy

Abstract

The present invention relates to a treatment liquid for appropriately removing a natural oxide film and organic matter present on the surface of copper or copper alloy. The present invention provides a chemical polishing liquid, which is a chemical polishing liquid for surface treatment of copper or copper alloy, comprising: (A) 0.1 to 3.5 mass % of hydrogen peroxide based on the total amount of the aforementioned chemical polishing liquid; (B) 1 to 20 mass % of one or more selected from the group consisting of sulfuric acid and nitric acid based on the total amount of the aforementioned chemical polishing liquid; (C) 0.05 to 0.8 mass % of fluoride as a content converted according to fluorine atoms based on the total amount of the aforementioned chemical polishing liquid; (D) 0.01 to 1 mass % of one or more selected from the group consisting of anthranilic acid, cyclohexylamine, cyclohexanol and 1,5-pentanediol based on the total amount of the aforementioned chemical polishing liquid; (E) 0.0005 to 0.005 mass % of a fluorine-based surfactant based on the total amount of the aforementioned chemical polishing liquid; and (F) water.

Description

Technical Field

[0001] The present invention relates to a chemical polishing liquid for surface treatment of copper or copper alloy, a surface treatment method of copper or copper alloy using the chemical polishing liquid, and a method for producing surface treated copper or copper alloy. Background Art

[0002] In lead frames used in semiconductor packaging, the surface of copper or copper alloy is sometimes plated with nickel, gold, etc. At this time, there are usually natural oxide films and organic matter on the surface of copper or copper alloy. If these are not removed and the plating process is performed, color unevenness (uneven plating) will occur and the plating thickness will become uneven.

[0003] Therefore, in order to suppress the occurrence of color unevenness accompanying the plating process and make the plating thickness uniform, it is desirable to appropriately remove the natural oxide film and organic matter on the surface of copper or copper alloy. However, using conventional chemical reagents (e.g., Patent Documents 1 to 3), there is a problem that a part of the natural oxide film and organic matter is not removed and remains, or color unevenness occurs after the plating process.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 9-184081

[0007] Patent Document 2: Japanese Patent Application Publication No. 2017-031502

[0008] Patent Document 3: Japanese Patent Application Publication No. 2017-195311 Summary of the invention

[0009] Problem that the invention aims to solve

[0010] Under such circumstances, a treatment solution for appropriately removing the natural oxide film and organic matter present on the surface of copper or copper alloy is required. When the surface of copper or copper alloy is treated, a part of copper or copper alloy can be dissolved in the treatment solution, but it is further desired to provide a treatment solution with stable removal performance of natural oxide film and organic matter regardless of their dissolved amount.

[0011] Solutions for solving problems

[0012] The present invention relates to the following chemical polishing liquid, surface treatment method and method for producing surface-treated copper or copper alloy.

[0013] [1] A chemical polishing liquid, which is a chemical polishing liquid for surface treatment of copper or copper alloy, comprising:

[0014] (A) 0.1 to 3.5 mass % of hydrogen peroxide based on the total amount of the chemical polishing liquid;

[0015] (B) 1 to 20% by mass of one or more selected from the group consisting of sulfuric acid and nitric acid, based on the total amount of the chemical polishing liquid;

[0016] (C) a fluoride having a content of 0.05 to 0.8% by mass based on the total amount of the chemical polishing liquid as converted to fluorine atoms;

[0017] (D) 0.01 to 4% by mass of one or more selected from the group consisting of anthranilic acid, cyclohexylamine, cyclohexanol and 1,5-pentanediol, based on the total amount of the chemical polishing liquid;

[0018] (E) 0.0005 to 0.005 mass % of a fluorine-based surfactant based on the total amount of the chemical polishing liquid; and

[0019] (F) Water.

[0020] [2] The chemical polishing liquid according to [1] above, wherein the pH of the chemical polishing liquid is 3 or less.

[0021] [3] The chemical polishing liquid according to [1] or [2], wherein the component (C) is one or more selected from the group consisting of acidic potassium fluoride, acidic ammonium fluoride and hydrogen fluoride.

[0022] [4] The chemical polishing liquid according to any one of [1] to [3] above, wherein the component (B) is sulfuric acid.

[0023] [5] The chemical polishing liquid according to any one of [1] to [4] above, wherein the component (D) contains one or more selected from the group consisting of cyclohexanol and cyclohexylamine.

[0024] [6] The chemical polishing liquid according to any one of [1] to [5] above, wherein the component (E) contains one or more groups selected from the group consisting of a perfluoroalkyl group, a perfluoroalkenyl group, and a perfluorophenyl group.

[0025] [7] A method for treating the surface of copper or a copper alloy, comprising the step of contacting the chemical polishing liquid described in any one of [1] to [6] with the surface of copper or a copper alloy to perform surface treatment on the copper or a copper alloy.

[0026] [8] The surface treatment method according to [7] above, wherein the temperature of the chemical polishing liquid during the surface treatment of copper or copper alloy is 25 to 50°C.

[0027] [9] The surface treatment method according to [7] or [8] above, wherein the time for contacting the chemical polishing liquid with the surface of the copper or copper alloy to perform the surface treatment of the copper or copper alloy is from 1 second to 10 minutes.

[0028]

[10] A method for producing surface-treated copper or copper alloy, comprising the step of contacting the chemical polishing liquid described in any one of [1] to [6] with the surface of copper or copper alloy to perform surface treatment of the copper or copper alloy.

[0029]

[11] A method for producing a chemical polishing liquid as described in any one of [1] to [6] above, comprising the step of uniformly stirring at least the component (A), the component (B), the component (C), the component (D), the component (E) and the component (F).

[0030] Effects of the Invention

[0031] According to a preferred embodiment of the present invention, by using the chemical polishing liquid of the present invention to treat the surface of copper or copper alloy, the amount of copper or copper alloy dissolved can be suppressed to a small amount, and the natural oxide and organic matter present on the surface of copper or copper alloy can be appropriately removed, and a copper or copper alloy surface without color unevenness or with suppressed color unevenness can be obtained. According to a further preferred embodiment of the present invention, the chemical polishing liquid of the present invention is also excellent in storage stability. In addition, according to a further preferred embodiment of the present invention, even if the copper concentration in the chemical polishing liquid increases due to repeated use, the removal performance of the natural oxide film and organic matter is stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a photograph showing an example in which color unevenness of a surface-treated product caused by a chemical polishing liquid was observed.

[0033] Figure 2 This is a photograph showing an example in which color unevenness of a surface-treated product due to a chemical polishing liquid is not observed. DETAILED DESCRIPTION

[0034] 1. Chemical polishing fluid

[0035] The chemical polishing liquid of the present invention is a chemical polishing liquid for surface treatment of copper or copper alloy, which comprises:

[0036] (A) 0.1 to 3.5% by weight of hydrogen peroxide based on the total amount of the chemical polishing liquid;

[0037] (B) 1 to 20% by mass of one or more selected from the group consisting of sulfuric acid and nitric acid, based on the total amount of the chemical polishing liquid;

[0038] (C) a fluoride having a content of 0.05 to 0.8% by mass based on the total amount of the chemical polishing liquid as converted to fluorine atoms;

[0039] (D) 0.01 to 4% by mass of one or more selected from the group consisting of anthranilic acid, cyclohexylamine, cyclohexanol and 1,5-pentanediol, based on the total amount of the chemical polishing liquid;

[0040] (E) 0.0005 to 0.005 mass % of a fluorine-based surfactant based on the total amount of the chemical polishing liquid; and

[0041] (F) Water.

[0042] The chemical polishing liquid of the present invention is used to remove natural oxide films and organic matter present on the surface of copper or copper alloys. Here, "copper alloy" is not particularly limited as long as it is an alloy containing copper as a main component. The content of copper in the copper alloy is preferably 50% by mass or more, more preferably 60% by mass or more, further preferably 70% by mass or more, particularly preferably 80% by mass or more, particularly preferably 90% by mass or more, and can be 95% by mass or more.

[0043] (A) Hydrogen peroxide

[0044] In the chemical polishing liquid of the present invention, hydrogen peroxide (hereinafter also referred to as "component (A)") as an oxidant has the effect of oxidizing copper contained in copper or copper alloy. In general, hydrogen peroxide is preferably used in the form of an aqueous hydrogen peroxide solution in view of availability and operability. The grade of the aqueous hydrogen peroxide solution is not particularly limited, and various grades of aqueous hydrogen peroxide solutions such as those for industrial use and electronic industry use can be used.

[0045] In the chemical polishing liquid of the present invention, the content of hydrogen peroxide is 0.1-3.5 mass %, preferably 0.5-2.0 mass %, more preferably 0.7-1.6 mass % based on the total amount of the chemical polishing liquid, and from the viewpoint of the solubility of copper, it is further preferably 0.7-1.2 mass %. If the content of hydrogen peroxide is within the above range, natural oxide film and organic matter can be appropriately removed from the surface of copper or copper alloy. In addition, the amount of copper dissolved can be suppressed to be less, and local corrosion of copper or copper alloy is not easy to occur. It should be noted that when the numerical range is shown in this specification, the upper limit and the lower limit can be freely combined.

[0046] (B) one or more selected from the group consisting of sulfuric acid and nitric acid

[0047] In the chemical polishing liquid of the present invention, sulfuric acid and nitric acid promote the dissolution of copper or copper compounds contained in copper oxidized by component (A) or copper alloy oxidized by component (A), and the content of one or more selected from the group consisting of sulfuric acid and nitric acid (hereinafter also referred to as "component (B)") is 1 to 20 mass %, preferably 3 to 18 mass %, more preferably 4 to 16 mass %, and further preferably 5 to 15 mass % based on the total amount of the chemical polishing liquid. When sulfuric acid and nitric acid are used as components (B), their total amount satisfies the above range. If the content of component (B) is within the above range, natural oxide film and organic matter can be appropriately removed from the surface of copper or copper alloy. In addition, the amount of copper dissolved can be suppressed to be less, and local corrosion of copper or copper alloy is not easy to occur. Considering the wide range of the selection of containers when storing the chemical polishing liquid of the present invention, sulfuric acid is particularly preferred as component (B).

[0048] (C) Fluoride

[0049] In the chemical polishing liquid of the present invention, the fluoride (hereinafter also referred to as "component (C)") is not particularly limited as long as it generates fluoride ions in the chemical polishing liquid, and is preferably selected from one or more of the group consisting of acidic potassium fluoride, acidic ammonium fluoride and hydrogen fluoride. Among these, acidic potassium fluoride and acidic ammonium fluoride are more preferred, and acidic potassium fluoride is particularly preferred from the viewpoint of low toxicity.

[0050] In the chemical polishing liquid of the present invention, the content of fluoride is 0.05-0.8 mass %, preferably 0.1-0.6 mass %, more preferably 0.15-0.5 mass %, and further preferably 0.2-0.4 mass % as the content converted according to fluorine atoms based on the total amount of chemical polishing liquid. When two or more fluorides are used as component (C), their total amount satisfies the above range. If the content of fluoride is within the above range, natural oxide film and organic matter can be appropriately removed from the surface of copper or copper alloy. In addition, the amount of copper dissolved can be suppressed to be less, and local corrosion of copper or copper alloy is not easy to occur.

[0051] (D) at least one selected from the group consisting of anthranilic acid, cyclohexylamine, cyclohexanol and 1,5-pentanediol

[0052] In the chemical polishing liquid of the present invention, o-aminobenzoic acid, cyclohexylamine, cyclohexanol and 1,5-pentanediol are adsorbed on the surface of copper and copper alloy, and play a role in the removal of natural oxide film, organic matter and the solubility of copper. The content of one or more selected from the group consisting of o-aminobenzoic acid, cyclohexylamine, cyclohexanol and 1,5-pentanediol (hereinafter also referred to as "component (D)") is 0.01 to 4 mass %, preferably 0.05 to 3.5 mass %, more preferably 0.1 to 3.3 mass %, and further preferably 0.2 to 3 mass % based on the total amount of chemical polishing liquid. When using two or more as component (D), their total amount satisfies the above range. If the content of component (D) is within the above range, natural oxide film and organic matter can be appropriately removed from the surface of copper or copper alloy. In addition, the amount of copper dissolved can be suppressed to be less, and local corrosion of copper or copper alloy is not easy to occur. If the storage stability of the chemical polishing liquid is considered, cyclohexylamine, cyclohexanol or a combination thereof is preferred as component (D).

[0053] (E) Fluorine-based surfactants

[0054] In the chemical polishing liquid of the present invention, the fluorine-based surfactant (hereinafter also referred to as "component (E)") is adsorbed on the surface of copper and copper alloys, and exerts effects on the removal of natural oxide film and organic matter and the solubility of copper. The chemical polishing liquid of the present invention contains component (E), so that even if the copper concentration in the chemical polishing liquid increases due to repeated use, the removal performance of natural oxide film and organic matter tends to be stable.

[0055] The fluorine-based surfactant preferably contains one or more groups selected from the group consisting of a perfluoroalkyl group, a perfluoroalkenyl group, and a perfluorophenyl group, and more preferably contains a perfluoroalkyl group.

[0056] Examples of the fluorine-based surfactant include perfluoroalkyl carboxylates, perfluoroalkyl sulfonates, perfluoroalkyl quaternary ammonium salts, perfluoroalkyl phosphates, perfluoroalkyl phosphonates, perfluoroalkyl ethylene oxide adducts, perfluoroalkyl amine oxides, perfluoroalkyl carboxylates, perfluoroalkyl phosphates, perfluoroalkyl phosphonates, and perfluoroalkyl-containing oligomers.

[0057] Perfluoroalkenyl carboxylates, perfluoroalkenyl sulfonates, perfluoroalkenyl quaternary ammonium salts, perfluoroalkenyl phosphates, perfluoroalkenyl phosphonates, perfluoroalkenyl ethylene oxide adducts, perfluoroalkenyl amine oxides, perfluoroalkenyl carboxylates, perfluoroalkenyl phosphates, perfluoroalkenyl phosphonates, and perfluoroalkenyl-containing oligomers;

[0058] Perfluorophenyl carboxylates, perfluorophenyl sulfonates, perfluorophenyl quaternary ammonium salts, perfluorophenyl phosphates, perfluorophenyl phosphonates, perfluorophenyl ethylene oxide adducts, perfluorophenyl amine oxides, perfluorophenyl carboxylates, perfluorophenyl phosphates, perfluorophenyl phosphonates, perfluorophenyl-containing oligomers, and the like.

[0059] In the chemical polishing liquid of the present invention, the content of the fluorine-based surfactant is 0.0005-0.005 mass %, preferably 0.0006-0.004 mass %, more preferably 0.0007-0.003 mass %, and further preferably 0.0007-0.002 mass % based on the total amount of the chemical polishing liquid. When two or more are used as component (E), their total amount satisfies the above range. If the content of the fluorine-based surfactant is within the above range, the wettability of the surface of the copper or copper alloy is improved, and surface treatment can be performed more uniformly. In addition, even if the copper concentration in the chemical polishing liquid increases due to repeated use, the removal performance of the natural oxide film and organic matter tends to be stable.

[0060] (F) Water

[0061] The chemical polishing liquid of the present invention contains water (hereinafter also referred to as "component (F)") as a diluent. The water is preferably water from which metal ions, organic impurities and particles have been removed by distillation, ion exchange treatment, filter treatment, various adsorption treatments, etc., and pure water or ultrapure water is particularly preferred. The content of water is the balance of the above-mentioned components (A) to (E) and any component, and is preferably 40% by mass or more, more preferably in the range of 40 to 99% by mass, further preferably 50 to 97% by mass, particularly preferably 60 to 95% by mass, and particularly preferably 70 to 95% by mass, based on the total amount of the chemical polishing liquid.

[0062] (G) Other ingredients

[0063] The chemical polishing liquid of the present invention may contain various additives such as alcohols, urea, organic carboxylic acids and other known hydrogen peroxide stabilizers commonly used in chemical polishing liquids, in addition to the above-mentioned components (A) to (F), within the range that does not impair the effect of the chemical polishing liquid.

[0064] It should be noted that the chemical polishing liquid of the present invention is preferably a dissolving liquid and does not contain solid particles such as abrasive particles.

[0065] <pH range>

[0066] The pH range of the chemical polishing liquid of the present invention is not particularly limited, but is preferably below 3, more preferably below 2, and further preferably below 1. The pH can be measured, for example, by the method described in the Examples. For example, when measured by the method described in the Examples, the lower limit of the pH of the chemical polishing liquid of the present invention is preferably -2.

[0067] In the chemical polishing liquid of the present invention, a pH adjusting agent may be added as needed to adjust the pH range. As the pH adjusting agent, for example, potassium hydroxide, sodium hydroxide, lithium hydroxide, cesium hydroxide, triethylamine, ammonia, tetramethylammonium hydroxide, ethanolamine, 1-amino-2-propanol, etc. may be used. The pH adjusting agent may be used alone or in combination of two or more.

[0068] <Preparation method>

[0069] The chemical polishing liquid of the present invention can be prepared by uniformly stirring component (A) to component (F) and further other components as needed. The stirring method of these components is not particularly limited, and the stirring method commonly used in the preparation of the chemical polishing liquid can be adopted. It should be noted that a part or all of the water of component (F) can be added later. In addition, a liquid containing component (A) to component (E), a part of component (F) and further other components as needed can also be prepared in advance and stored, and then used after diluting with the remainder of component (F) when used.

[0070] <Amount of copper or copper alloy dissolved>

[0071] The chemical polishing liquid of the present invention is used for surface treatment, so that the natural oxide film and organic matter present on the surface of copper or copper alloy can be removed. At this time, the dissolution amount of copper or copper alloy is preferably as little as possible. If the dissolution amount of copper or copper alloy is large, the thickness of copper or copper alloy is prone to differences, and it is difficult to make the plating thickness uniform when the plating treatment is then carried out. In addition, if the dissolution amount of copper or copper alloy is large, uneven color is produced on the surface of copper or copper alloy and it is not preferred. For example, the dissolution amount of copper or copper alloy accompanied by surface treatment is preferably less than 4 μm, more preferably less than 2 μm, and further preferably less than 1 μm from an economic point of view. The dissolution amount of copper or copper alloy can be measured by the method described in the embodiments.

[0072] The dissolution rate of copper or copper alloy accompanying the surface treatment using the chemical polishing liquid of the present invention is not particularly limited, but is preferably 0.1 to 24 μm / min, more preferably 0.2 to 10 μm / min, and further preferably 0.4 to 5 μm / min in order to make the treatment time within an appropriate range.

[0073] According to a preferred embodiment of the present invention, the surface of copper or copper alloy is treated by using the chemical polishing liquid of the present invention, so that the dissolution amount of copper or copper alloy can be suppressed to a small amount, the natural oxides and organic matter present on the surface of copper or copper alloy can be properly removed, and the surface of copper or copper alloy without color unevenness or with suppressed color unevenness can be obtained.

[0074] 2. Surface treatment method

[0075] The surface treatment method of the present invention comprises the step of contacting the chemical polishing liquid of the present invention with the surface of copper or copper alloy to perform surface treatment of copper or copper alloy. According to a preferred embodiment of the present invention, by using the chemical polishing liquid of the present invention to perform surface treatment of copper or copper alloy, the amount of copper or copper alloy dissolved can be suppressed, and natural oxides and organic matter present on the surface of copper or copper alloy can be appropriately removed, so that a copper or copper alloy surface without color unevenness or with suppressed color unevenness can be obtained.

[0076] In the present invention, the method for contacting the chemical polishing liquid with the surface of copper or copper alloy is not particularly limited. For example, preferably, a method for contacting the chemical polishing liquid with the surface of copper or copper alloy by dripping (single-wafer rotation processing), spraying, etc., a method for immersing the surface of copper or copper alloy in the chemical polishing liquid, etc.

[0077] The temperature of the chemical polishing liquid during the surface treatment of copper or copper alloy is not particularly limited, and is generally, for example, 0 to 70°C, preferably 25 to 50°C, more preferably 25 to 45°C, and further preferably 30 to 40°C. If the temperature of the chemical polishing liquid is above 25°C, the chemical polishing rate will not become too slow, thereby suppressing the reduction in production efficiency. On the other hand, if it is below 50°C, the liquid composition change can be suppressed, and the surface treatment conditions can be kept constant. By increasing the temperature of the chemical polishing liquid, the chemical polishing rate increases, but on the basis of also considering suppressing the composition change of the chemical polishing liquid to be smaller, the optimal treatment temperature can be appropriately determined.

[0078] The time (treatment time) for contacting the surface of copper or copper alloy with chemical polishing liquid to perform surface treatment of copper or copper alloy is not particularly limited, and is usually preferably 1 second or more and 10 minutes or less, more preferably 10 seconds or more and 5 minutes or less, and further preferably 20 seconds or more and 3 minutes or less. The best treatment time can be appropriately selected according to the contact method between the surface of copper or copper alloy and chemical polishing liquid, the temperature of chemical polishing liquid, etc.

[0079] Before using the chemical polishing liquid of the present invention to perform surface treatment on copper or copper alloy, the surface of copper or copper alloy may be degreased using an organic solvent such as alcohol or acetone as needed.

[0080] After the chemical polishing liquid of the present invention is contacted with the surface of copper or copper alloy to carry out the surface treatment of copper or copper alloy, it can be suitably cleaned with water or sulfuric acid as required. In addition, it is also possible to carry out the rust prevention treatment utilizing the neutralization treatment of sodium carbonate or utilizing the aqueous solution comprising rust inhibitor.

[0081] 3. Method for manufacturing surface-treated copper or copper alloy

[0082] The present invention also includes a method for producing surface-treated copper or copper alloy, which includes the step of contacting the chemical polishing liquid with the surface of the copper or copper alloy to perform surface treatment of the copper or copper alloy.

[0083] By bringing the chemical polishing liquid of the present invention into contact with the surface of copper or copper alloy to perform surface treatment on copper or copper alloy, the natural oxide film and organic matter present on the surface of copper or copper alloy can be removed, and copper or copper alloy without surface color unevenness or with suppressed surface color unevenness can be obtained.

[0084] Example

[0085] Hereinafter, the present invention will be described in further detail using Examples and Comparative Examples, but the present invention is not limited to these Examples at all.

[0086] The methods for measuring the physical properties of the chemical polishing liquid, the physical properties of copper and copper alloys, the method for evaluating the amount of copper or copper alloy dissolved in the surface-treated product, and the method for evaluating the uneven treatment of the surface-treated product in the Examples and Comparative Examples are as follows.

[0087] (1) pH determination of chemical polishing liquid

[0088] The pH of the chemical polishing liquid at 25° C. was measured using a pH meter (manufactured by Horiba, Ltd., product name “D-53”) in accordance with JIS Z8802.

[0089] (2) Types of copper and copper alloys

[0090] The following 4 types of copper or copper alloys are used.

[0091] (a) Corson copper-nickel-silicon alloy (NKC-4419-H): thickness 0.2 mm, length 50 × width 30 mm (manufactured by Testpiece Co., Ltd.), Co: 1.9 mass%, Si: 0.44 mass%, Cu: balance

[0092] (b) Pure copper: 0.2 mm thick, 50 mm long x 30 mm wide (manufactured by Testpiece Co., Ltd.), Cu: 100% by mass

[0093] (c) Phosphor bronze: thickness 0.2 mm, length 50 × width 30 mm (manufactured by Testpiece Co., Ltd.), Sn: 5.5 to 7.0 mass%, P: 0.03 to 0.35 mass%, Pb: 0.02 mass% or less, Fe: 0.1 mass% or less, Zn: 0.2 mass% or less, Cu: balance, Cu+Sn+P: 99.5 mass% or more

[0094] (d) Be bronze: 0.2 mm thick, 50 mm long x 30 mm wide (manufactured by Testpiece Co., Ltd.), Be: 1.8 to 2.0 mass%, Co+Ni: 0.2 mass% or more, Co+Ni+Fe: 0.6 mass% or less, Cu+Be+Co+Ni+Fe: 99.5 mass% or more

[0095] (3) Evaluation of the amount of copper or copper alloy dissolved during surface treatment

[0096] The copper sheet or copper alloy sheet was immersed in the chemical polishing liquid at a liquid temperature of 30°C for 30 seconds. Then, the copper sheet or copper alloy sheet after immersion was taken out from the chemical polishing liquid, washed with ion exchange water, and then dried to obtain a surface treated product. The amount of dissolution was calculated according to the following formula from the weight loss before and after the surface treatment.

[0097] Dissolved amount [μm] = (mass before treatment [g] - mass after treatment [g]) / (treatment area of ​​copper sheet or copper alloy sheet [m 2 ]×8.92[g / cm 3 ](Specific gravity of copper)

[0098] (4) Evaluation of treatment unevenness of surface treated products

[0099] The surface condition of the surface-treated product was visually observed to evaluate the presence or absence of uneven treatment. Figure 1 This is a photograph showing an example in which color unevenness of a surface-treated product caused by a chemical polishing liquid was observed. Figure 2 This is a photograph showing an example in which color unevenness of a surface-treated product due to a chemical polishing liquid is not observed.

[0100] Example 1

[0101] (1) Preparation of chemical polishing liquid

[0102] 1.6 parts by mass of hydrogen peroxide (manufactured by Mitsubishi Gas Chemical Co., Ltd., 60% by mass aqueous solution) (effective ingredient ratio calculated as hydrogen peroxide, described as "hydrogen peroxide solution" in the Examples and Comparative Examples table), 14.1 parts by mass of sulfuric acid (manufactured by Mitsubishi Gas Chemical Co., Ltd., 46% by mass aqueous solution) (effective ingredient ratio calculated as sulfuric acid), 0.9 parts by mass of potassium acid fluoride (manufactured by Yamato Chemical Co., Ltd.) (0.4 parts by mass in terms of fluorine atom conversion), 0.09 parts by mass of anthranilic acid (manufactured by Samsung Chemical Industries, Ltd.), and 0.0018 parts by mass of a fluorine-based surfactant "Surflon S-243" (manufactured by AGC SEIMI CHEMICAL CO., LTD., a fluorine-based nonionic surfactant having a perfluoroalkyl group) were mixed, and water was added so that the amount was 83.3 parts by mass (balance) in the chemical polishing liquid to prepare a chemical polishing liquid.

[0103] (2) Surface treatment of copper and copper alloys

[0104] The copper sheet or copper alloy sheet was immersed in the chemical polishing liquid at a liquid temperature of 30° C. for 30 seconds. Then, the immersed copper sheet or copper alloy sheet was taken out from the chemical polishing liquid, washed thoroughly with ion exchange water, and then dried thoroughly to obtain a surface treated product.

[0105] The evaluation results of the amount of copper or copper alloy dissolved during the surface treatment and the treatment unevenness of the surface treated product are shown in Table 1-2.

[0106] Embodiments 2 to 12

[0107] The chemical polishing liquid was prepared in the same manner as in Example 1, except that the composition of the chemical polishing liquid was changed to that described in Table 1-1, and the surface treatment of copper and copper alloy was performed. It should be noted that (A), (B), (C), (D), (E) and (F) in Table 1-1 represent the above-mentioned component (A), component (B), component (C), component (D), component (E) and component (F), respectively. The same applies to Tables 2 to 5.

[0108] The evaluation results of the amount of copper or copper alloy dissolved during the surface treatment and the treatment unevenness of the surface treated product are shown in Table 1-2.

[0109] [Table 1-1]

[0110]

[0111] [Table 1-2]

[0112]

[0113] Embodiments 13 to 15

[0114] Except that the composition of the chemical polishing liquid was changed to that described in Table 2, a chemical polishing liquid was prepared in the same manner as in Example 1, and the surface treatment of copper and copper alloy was carried out.

[0115] Table 2 shows the evaluation results of the amount of copper or copper alloy dissolved during the surface treatment and the treatment unevenness of the surface treated product.

[0116] [Table 2]

[0117]

[0118] Comparative Examples 1 to 15

[0119] Except that the composition of the chemical polishing liquid was changed to that described in Table 3, a chemical polishing liquid was prepared in the same manner as in Example 1, and the surface treatment of copper and copper alloy was carried out.

[0120] Table 3 shows the evaluation results of the amount of copper or copper alloy dissolved during the surface treatment and the treatment unevenness of the surface treated product.

[0121] [Table 3]

[0122]

[0123] Embodiments 16 to 21

[0124] The composition of the chemical polishing liquid was changed to that shown in Table 4 to obtain a surface-treated product. Specifically, a storage liquid prepared by mixing components (A) to (F) was stored at room temperature (20°C ± 5°C) for 3 months, and then diluted with water to prepare a chemical polishing liquid, and the surface treatment of copper and copper alloy was carried out in the same manner as in Example 1 to obtain a surface-treated product.

[0125] The evaluation results of the amount of copper or copper alloy dissolved during the surface treatment and the uneven treatment of the surface treated product are shown in Table 4. Table 4 also lists the evaluation results of the amount of copper or copper alloy dissolved during the surface treatment and the uneven treatment of the surface treated product using a chemical polishing solution having the same composition except that the storage solution was not stored at room temperature for 3 months for comparison.

[0126] As shown in Table 4, it can be seen that when cyclohexylamine or cyclohexanol is used as the component (D), it is excellent also in terms of storage stability.

[0127] [Table 4]

[0128]

[0129] Embodiment 22

[0130] The composition of the chemical polishing liquid was changed to that shown in Table 5, and the copper alloy (NKC-4419-H) was dissolved in an amount of 5 g / L. The chemical polishing liquid was prepared in the same manner as in Example 1, and the surface treatment of the copper alloy (NKC-4419-H) was performed to obtain a surface-treated product.

[0131] The evaluation results of the amount of copper dissolved in the surface treatment and the uneven treatment of the surface treated product are shown in Table 5. For comparison, Table 5 also records the results of the evaluation of the amount of copper dissolved in the surface treatment and the uneven treatment of the surface treated product of the chemical polishing liquid of Example 5 having the same composition as Example 22 except that the copper alloy (NKC-4419-H) is not dissolved.

[0132] Comparative Examples 16 and 17

[0133] The composition of the chemical polishing liquid was changed to that shown in Table 5. Regarding Comparative Example 17, the copper alloy (NKC-4419-H) was further dissolved in an amount of 5 g / L. Otherwise, the chemical polishing liquid was prepared in the same manner as in Example 1, and the surface treatment of the copper alloy (NKC-4419-H) was performed to obtain a surface-treated product.

[0134] Table 5 shows the evaluation results of the amount of copper dissolved during the surface treatment and the treatment unevenness of the surface treated product.

[0135] [Table 5]

[0136]

[0137] As shown in Table 5, by comparing the results of Comparative Examples 16 and 17, it can be seen that when component (E) is not mixed, uneven treatment occurs when copper is dissolved. The chemical polishing liquid of the present invention can suppress the occurrence of uneven treatment even if the amount of copper dissolved in the liquid increases by mixing component (E), and can provide a chemical polishing liquid with stable removal performance.

Claims

1. A chemical polishing liquid, which is a chemical polishing liquid for surface treatment of copper or copper alloy, comprising: (A) 0.1 to 3.5 mass % of hydrogen peroxide based on the total amount of the chemical polishing liquid; (B) 1 to 20% by mass of one or more selected from the group consisting of sulfuric acid and nitric acid, based on the total amount of the chemical polishing liquid; (C) a fluoride having a content of 0.05 to 0.8% by mass based on the total amount of the chemical polishing liquid as converted to fluorine atoms; (D) 0.01 to 4% by mass of one or more selected from the group consisting of cyclohexylamine, cyclohexanol and 1,5-pentanediol, based on the total amount of the chemical polishing liquid; (E) 0.0005 to 0.005 mass % of a fluorine-based surfactant based on the total amount of the chemical polishing liquid; and (F) Water.

2. The chemical polishing liquid according to claim 1, wherein The pH of the chemical polishing liquid is below 3.

3. The chemical polishing liquid according to claim 1 or 2, wherein: The component (C) is at least one selected from the group consisting of acidic potassium fluoride, acidic ammonium fluoride and hydrogen fluoride.

4. The chemical polishing liquid according to claim 1 or 2, wherein: The component (B) is sulfuric acid.

5. The chemical polishing liquid according to claim 1 or 2, wherein: The component (D) includes one or more selected from the group consisting of cyclohexanol and cyclohexylamine.

6. The chemical polishing liquid according to claim 1 or 2, wherein: The component (E) contains one or more groups selected from the group consisting of a perfluoroalkyl group, a perfluoroalkenyl group, and a perfluorophenyl group. 7 . A method for treating the surface of copper or a copper alloy, comprising the step of contacting the chemical polishing liquid according to claim 1 with a surface of copper or a copper alloy to treat the surface of the copper or the copper alloy.

8. The surface treatment method according to claim 7, wherein: The temperature of the chemical polishing liquid during the surface treatment of copper or copper alloy is 25 to 50°C.

9. The surface treatment method according to claim 7 or 8, wherein: The time for contacting the chemical polishing liquid with the surface of copper or copper alloy to perform surface treatment of copper or copper alloy is 1 second or longer and 10 minutes or shorter.

10. A method for producing surface-treated copper or copper alloy, comprising the step of contacting the chemical polishing liquid according to any one of claims 1 to 6 with the surface of copper or copper alloy to perform surface treatment on the copper or copper alloy.

11. A method for producing a chemical polishing liquid according to any one of claims 1 to 6, comprising the step of uniformly stirring at least component (A), component (B), component (C), component (D), component (E) and component (F).

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