Chemical polishing solution used for surface treatment of copper or copper alloy and surface treatment method

Abstract

The present invention pertains to a treatment solution for appropriately removing natural oxide films or organic substances present on the surface of copper or copper alloys. The present invention provides a chemical polishing solution used for surface treatment of copper or copper alloys, the chemical polishing solution containing, on the basis of the total amount of the chemical polishing solution, (A) 0.1-3.5 mass% of hydrogen peroxide, (B) 1-20 mass% of at least one selected from the group consisting of sulfuric acid and nitric acid, (C) 0.05-0.8 mass% of a fluoride in terms of fluorine atoms, (D) 0.01-1 mass% of at least one selected from the group consisting of anthranilic acid, cyclohexylamine, cyclohexanol, and 1,5-pentanediol, (E) 0.0005-0.005 mass% of a fluorine-based surfactant, and (F) water.

Description

[Technical Field]

[0001] The present invention relates to a chemical polishing solution used for surface treatment of copper or copper alloys, a method for surface treatment of copper or copper alloys using the same, and a method for producing surface-treated copper or copper alloys. [Background technology]

[0002] Lead frames used in semiconductor packages are sometimes plated with nickel or gold on the copper or copper alloy surface. Natural oxide films and organic matter are usually present on the copper or copper alloy surface. Plating without removing these can result in uneven color (plating) or uneven plating thickness. Therefore, in order to prevent color unevenness during plating and to achieve a uniform plating thickness, it is desirable to properly remove the natural oxide film and organic matter from the surface of copper or copper alloy. However, with conventional chemical solutions (e.g., Patent Documents 1 to 3), some of the natural oxide film and organic matter remain unremoved, which can cause color unevenness after plating. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-184081 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-031502 [Patent Document 3] Japanese Patent Application Publication No. 2017-195311 Summary of the Invention [Problem to be solved by the invention]

[0004] In this situation, there is a need for a treatment solution that can adequately remove natural oxide films and organic matter present on the surface of copper or copper alloys. Although a portion of the copper or copper alloy may dissolve in the treatment solution when the surface of the copper or copper alloy is treated, it is more desirable to provide a treatment solution that has stable performance in removing natural oxide films and organic matter, regardless of the amount of dissolution. [Means for solving the problem]

[0005] The present invention relates to the following chemical polishing solution, surface treatment method, and method for producing surface-treated copper or copper alloy. [1] A chemical polishing solution used for surface treatment of copper or copper alloys, (A) hydrogen peroxide, 0.1 to 3.5 mass% based on the total amount of the chemical polishing solution; (B) one or more selected from the group consisting of sulfuric acid and nitric acid, in an amount of 1 to 20 mass % based on the total amount of the chemical polishing solution; (C) a fluoride content, calculated as fluorine atoms, of 0.05 to 0.8 mass% based on the total mass of the chemical polishing solution; (D) one or more selected from the group consisting of anthranilic acid, cyclohexylamine, cyclohexanol, and 1,5-pentanediol, in an amount of 0.01 to 4 mass% based on the total mass of the chemical polishing liquid; (E) a fluorosurfactant in an amount of 0.0005 to 0.005% by mass based on the total mass of the chemical polishing liquid; and (F)Water A chemical polishing solution comprising: [2] The chemical polishing solution according to [1], wherein the pH of the chemical polishing solution is 3 or less. [3] The chemical polishing liquid according to [1] or [2], wherein the component (C) is at least one selected from the group consisting of acid potassium fluoride, acid ammonium fluoride, and hydrogen fluoride. [4] The chemical polishing slurry according to any one of [1] to [3], wherein the component (B) is sulfuric acid. [5] The chemical polishing liquid according to any one of [1] to [4], wherein the component (D) comprises at least one member selected from the group consisting of cyclohexanol and cyclohexylamine. [6] The chemical polishing liquid according to any one of [1] to [5], 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 contacting the surface of copper or a copper alloy with the chemical polishing solution according to any one of [1] to [6] above, to treat the surface of the copper or copper alloy. [8] The surface treatment method according to [7] above, wherein the temperature of the chemical polishing solution during the surface treatment of copper or copper alloy is 25 to 50°C. [9] The surface treatment method according to [7] or [8], wherein the time for contacting the copper or copper alloy surface with the chemical polishing solution to perform the copper or copper alloy surface treatment is 1 second or more and 10 minutes or less.

[10] A method for producing a surface-treated copper or copper alloy, comprising contacting the surface of copper or a copper alloy with the chemical polishing solution according to any one of [1] to [6] above to treat the surface of the copper or copper alloy.

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

[0006] According to a preferred embodiment of the present invention, by treating the surface of copper or a copper alloy with the chemical polishing solution of the present invention, it is possible to appropriately remove native oxides and organic matter present on the surface of the copper or copper alloy while minimizing the amount of dissolution of the copper or copper alloy, thereby obtaining a copper or copper alloy surface that is free of color unevenness or in which the occurrence of color unevenness is suppressed. According to a further preferred embodiment of the present invention, the chemical polishing solution of the present invention is also excellent in terms of storage stability. Furthermore, according to a further preferred embodiment of the present invention, the chemical polishing solution of the present invention has stable performance in removing native oxides and organic matter even when the copper concentration in the chemical polishing solution increases with repeated use. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a photograph showing an example in which color unevenness was observed on an item surface-treated with a chemical polishing solution. [Figure 2] 1 is a photograph showing an example in which no color unevenness was observed on an item surface-treated with a chemical polishing solution. DETAILED DESCRIPTION OF THE INVENTION

[0008] 1.Chemical polishing liquid The chemical polishing liquid of the present invention is a chemical polishing liquid used for surface treatment of copper or copper alloy, (A) hydrogen peroxide, 0.1 to 3.5 mass% based on the total amount of the chemical polishing solution; (B) one or more selected from the group consisting of sulfuric acid and nitric acid in an amount of 1 to 20 mass% in total based on the total amount of the chemical polishing solution; (C) a fluoride content, calculated as fluorine atoms, of 0.05 to 0.8 mass% based on the total mass of the chemical polishing solution; (D) one or more selected from the group consisting of anthranilic acid, cyclohexylamine, cyclohexanol, and 1,5-pentanediol, in an amount of 0.01 to 4 mass% based on the total mass of the chemical polishing liquid; (E) a fluorosurfactant in an amount of 0.0005 to 0.005% by mass based on the total mass of the chemical polishing liquid; and (F)Water The present invention is characterized by comprising: The chemical polishing solution of the present invention is used to remove natural oxide films and organic substances present on the surface of copper or copper alloys. Here, the "copper alloy" is not particularly limited as long as it is an alloy containing copper as a main component. The copper content in the copper alloy is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more, and may even be 95% by mass or more.

[0009] (A) Hydrogen peroxide In the chemical polishing solution of the present invention, hydrogen peroxide (hereinafter also referred to as "component (A)") acts as an oxidizing agent to oxidize copper contained in copper or copper alloys. It is generally preferable to use hydrogen peroxide as an aqueous hydrogen peroxide solution in terms of availability and ease of use. There are no particular restrictions on the grade of the aqueous hydrogen peroxide solution, and various grades, such as those for industrial and electronics industries, can be used.

[0010] In the chemical polishing solution of the present invention, the content of hydrogen peroxide is 0.1 to 3.5 mass% based on the total amount of the chemical polishing solution, preferably 0.5 to 2.0 mass%, more preferably 0.7 to 1.6 mass%, and even more preferably 0.7 to 1.2 mass% from the viewpoint of copper solubility. If the content of hydrogen peroxide is within the above range, native oxide films and organic matter can be appropriately removed from the surface of copper or copper alloys. Furthermore, the amount of copper dissolved can be kept low, making localized corrosion of copper or copper alloys less likely to occur. Note that, when numerical ranges are given in this specification, the upper and lower limits can be freely combined.

[0011] (B) one or more selected from the group consisting of sulfuric acid and nitric acid In the chemical polishing solution of the present invention, sulfuric acid and nitric acid promote dissolution of copper oxidized by component (A) or copper or copper compounds contained in a copper alloy oxidized by component (A). 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% based on the total mass of the chemical polishing solution, preferably 3 to 18 mass%, more preferably 4 to 16 mass%, and even more preferably 5 to 15 mass%. When both sulfuric acid and nitric acid are used as component (B), their total amount should be within the above range. When the content of component (B) is within the above range, native oxide films and organic matter can be appropriately removed from the surface of copper or copper alloys. Furthermore, the amount of copper dissolved can be kept low, thereby preventing localized corrosion of copper or copper alloys. Sulfuric acid is particularly preferred as component (B) because it allows for a wider range of containers to be selected for storing the chemical polishing solution of the present invention.

[0012] (C) Fluoride In the chemical polishing solution 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 solution, but is preferably at least one selected from the group consisting of potassium acid fluoride, ammonium acid fluoride, and hydrogen fluoride. Among these, potassium acid fluoride and ammonium acid fluoride are more preferred, with potassium acid fluoride being particularly preferred, from the viewpoint of low toxicity.

[0013] In the chemical polishing solution of the present invention, the fluoride content, calculated as fluorine atoms, is 0.05 to 0.8 mass% based on the total mass of the chemical polishing solution, preferably 0.1 to 0.6 mass%, more preferably 0.15 to 0.5 mass%, and even more preferably 0.2 to 0.4 mass%. When two or more fluorides are used as component (C), the total amount of these fluorides should be within the above range. When the fluoride content is within the above range, native oxide films and organic matter can be adequately removed from the surface of copper or copper alloys. Furthermore, the amount of copper dissolved can be kept low, making localized corrosion of copper or copper alloys less likely to occur.

[0014] (D) one or more members selected from the group consisting of anthranilic acid, cyclohexylamine, cyclohexanol, and 1,5-pentanediol In the chemical polishing solution of the present invention, anthranilic acid, cyclohexylamine, cyclohexanol, and 1,5-pentanediol are adsorbed onto the surface of copper or copper alloys, and act to remove native oxide films and organic matter, as well as to dissolve copper. The content of one or more components selected from the group consisting of anthranilic 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 even more preferably 0.2 to 3 mass%, based on the total mass of the chemical polishing solution. When two or more components are used as component (D), the total amount of these components should be within the above range. The content of component (D) within the above range allows for adequate removal of native oxide films and organic matter from the surface of copper or copper alloys. Furthermore, the amount of copper dissolved can be kept low, thereby reducing the likelihood of localized corrosion of copper or copper alloys. In consideration of the storage stability of the chemical polishing liquid, cyclohexylamine, cyclohexanol, or a combination thereof is preferred as component (D).

[0015] (E) Fluorosurfactants In the chemical polishing solution of the present invention, the fluorochemical surfactant (hereinafter also referred to as "component (E)") is adsorbed to the surface of copper and copper alloys, and acts on the removal of native oxide films and organic matter and the solubility of copper. By including component (E), the chemical polishing solution of the present invention tends to have stable performance in removing native oxide films and organic matter, even if the copper concentration in the chemical polishing solution increases with repeated use. 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. Fluorine-based surfactants 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; perfluoroalkenyl carboxylates, perfluoroalkenyl sulfonates, perfluoroalkenyl quaternary ammonium salts, perfluoroalkenyl phosphates, perfluoroalkenyl phosphonates, perfluoroalkenyl ethylene oxide adducts, perfluoroalkenyl amine oxides, perfluoroalkenyl carboxylate esters, perfluoroalkenyl phosphate esters, perfluoroalkenyl phosphonate esters, perfluoroalkenyl-containing oligomers; Examples thereof include perfluorophenyl carboxylates, perfluorophenyl sulfonates, perfluorophenyl quaternary ammonium salts, perfluorophenyl phosphates, perfluorophenyl phosphonates, perfluorophenyl ethylene oxide adducts, perfluorophenyl amine oxide, perfluorophenyl carboxylates, perfluorophenyl phosphates, perfluorophenyl phosphonates, and perfluorophenyl-containing oligomers.

[0016] In the chemical polishing solution of the present invention, the content of the fluorosurfactant is 0.0005 to 0.005 mass% based on the total amount of the chemical polishing solution, preferably 0.0006 to 0.004 mass%, more preferably 0.0007 to 0.003 mass%, and even more preferably 0.0007 to 0.002 mass%. When two or more types of surfactants are used as component (E), the total amount of these surfactants should be within the above range. When the content of the fluorosurfactant is within the above range, the wettability of the copper or copper alloy surface is improved, allowing for more uniform surface treatment. Furthermore, even if the copper concentration in the chemical polishing solution increases with repeated use, the ability to remove native oxide films and organic matter tends to remain stable.

[0017] (F) Water The chemical polishing liquid of the present invention contains water (hereinafter also referred to as "component (F)") as a diluent. Water is preferably one from which metal ions, organic impurities, particulate particles, etc. have been removed by distillation, ion exchange treatment, filter treatment, various adsorption treatments, etc., and particularly preferably pure water or ultrapure water. The content of water is the remainder of the above components (A) to (E) and optional components, and based on the total amount of the chemical polishing liquid, it is preferably 40% by mass or more, more preferably in the range of 40 to 99% by mass, still more preferably 50 to 97% by mass, yet more preferably 60 to 95% by mass, and particularly preferably 70 to 95% by mass.

[0018] (G) Other components In addition to the components (A) to (F) described above, the chemical polishing liquid of the present invention can contain various additives such as known hydrogen peroxide stabilizers such as alcohols, urea, organic carboxylic acids, etc. that are usually used in chemical polishing liquids, as long as the effects of the chemical polishing liquid are not inhibited. <x

[0019] In addition, the chemical polishing liquid of the present invention is preferably a solution and does not contain solid particles such as polishing particles.

[0020] <pH range> The pH range of the chemical polishing liquid of the present invention is not particularly limited, but it is preferably 3 or less, more preferably 2 or less, and still more preferably 1 or less. 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 value of the pH of the chemical polishing liquid of the present invention is preferably -2. A pH adjuster may be added to the chemical polishing liquid of the present invention as necessary to adjust the pH range. As the pH adjuster, for example, potassium hydroxide, sodium hydroxide, lithium hydroxide, cesium hydroxide, triethylamine, ammonia, tetramethylammonium hydroxide, ethanolamine, 1-amino-2-propanol, etc. can be used. The pH adjuster may be used alone or in combination of two or more.

[0021] <Preparation method> The chemical polishing solution of the present invention can be prepared by uniformly stirring components (A) through (F), and optionally other components. The method for stirring these components is not particularly limited, and any stirring method commonly used in preparing chemical polishing solutions can be employed. Note that some or all of the water in component (F) may be added later. Alternatively, a solution containing components (A) through (E), a portion of component (F), and optionally other components may be prepared and stored in advance, and then diluted with the remainder of component (F) before use.

[0022] <Amount of copper or copper alloy dissolved> Surface treatment using the chemical polishing solution of the present invention can remove natural oxide films and organic matter present on the surface of copper or copper alloys. In this case, it is preferable to minimize the amount of dissolved copper or copper alloy. If the amount of dissolved copper or copper alloy is large, variations in the thickness of the copper or copper alloy are likely to occur, making it difficult to achieve a uniform plating thickness when a subsequent plating treatment is performed. Furthermore, if the amount of dissolved copper or copper alloy is large, color unevenness may occur on the surface of the copper or copper alloy, which is undesirable. For example, from an economical point of view, the amount of dissolved copper or copper alloy during surface treatment is preferably 4 μm or less, more preferably 2 μm or less, and even more preferably 1 μm or less. The amount of dissolved copper or copper alloy can be measured by the method described in the Examples. The dissolution rate of copper or copper alloys during surface treatment using the chemical polishing liquid of the present invention is not particularly limited, but in order to keep the treatment time within an appropriate range, it is preferably 0.1 to 24 μm / min, more preferably 0.2 to 10 μm / min, and even more preferably 0.4 to 5 μm / min.

[0023] According to a preferred embodiment of the present invention, by treating the surface of copper or a copper alloy with the chemical polishing solution of the present invention, it is possible to appropriately remove natural oxides and organic substances present on the surface of the copper or copper alloy while keeping the amount of copper or copper alloy dissolved to a minimum, and to obtain a copper or copper alloy surface that is free of color unevenness or in which the occurrence of color unevenness is suppressed.

[0024] 2. Surface treatment method The surface treatment method of the present invention comprises contacting the surface of copper or a copper alloy with the aforementioned chemical polishing solution of the present invention to treat the surface of copper or a copper alloy. According to a preferred embodiment of the present invention, by treating the surface of copper or a copper alloy with the chemical polishing solution of the present invention, it is possible to appropriately remove native oxides and organic substances present on the surface of the copper or copper alloy while suppressing the amount of copper or copper alloy dissolved, thereby obtaining a copper or copper alloy surface that is free of color unevenness or in which the occurrence of color unevenness is suppressed.

[0025] In the present invention, the method for contacting the copper or copper alloy surface with the chemical polishing solution is not particularly limited. For example, a method for contacting the copper or copper alloy surface with the chemical polishing solution by dropping (single wafer spin treatment) or spraying, or a method for immersing the copper or copper alloy surface in the chemical polishing solution, is preferably employed.

[0026] The temperature of the chemical polishing solution when performing surface treatment on copper or copper alloys is not particularly limited, but is typically, for example, 0 to 70°C, preferably 25 to 50°C, more preferably 25 to 45°C, and even more preferably 30 to 40°C. If the temperature of the chemical polishing solution is 25°C or higher, the chemical polishing rate does not become too slow, thereby preventing a decrease in production efficiency. On the other hand, if the temperature is 50°C or lower, changes in the solution composition can be suppressed, and surface treatment conditions can be maintained constant. Increasing the temperature of the chemical polishing solution increases the chemical polishing rate, but the optimal treatment temperature can be determined appropriately, taking into consideration factors such as minimizing changes in the composition of the chemical polishing solution.

[0027] The time (treatment time) for contacting the copper or copper alloy surface with the chemical polishing solution to perform the copper or copper alloy surface treatment is not particularly limited, but is usually preferably 1 second or more and 10 minutes or less, more preferably 10 seconds or more and 5 minutes or less, and even more preferably 20 seconds or more and 3 minutes or less. The optimum treatment time can be selected appropriately depending on the method for contacting the copper or copper alloy surface with the chemical polishing solution, the temperature of the chemical polishing solution, etc.

[0028] Before performing surface treatment of copper or copper alloy with the chemical polishing liquid of the present invention, the surface of the copper or copper alloy may be degreased with an organic solvent such as alcohol or acetone, if necessary. After the surface of copper or a copper alloy is treated by contacting the surface of the copper or copper alloy with the chemical polishing solution of the present invention, the surface may be washed appropriately with water or sulfuric acid, if necessary. In addition, neutralization treatment with sodium carbonate or rust prevention treatment with an aqueous solution containing a rust inhibitor may be performed.

[0029] 3. Method for producing surface-treated copper or copper alloy The present invention also includes a method for producing a surface-treated copper or copper alloy, which comprises contacting the surface of copper or a copper alloy with the chemical polishing liquid to perform surface treatment of the copper or copper alloy. By contacting the surface of copper or a copper alloy with the chemical polishing solution of the present invention to perform surface treatment of the copper or copper alloy, it is possible to remove the natural oxide film and organic matter present on the surface of the copper or copper alloy, and to obtain copper or a copper alloy that is free from surface color unevenness or in which the occurrence of surface color unevenness is suppressed. [Example]

[0030] Next, the present invention will be explained in more detail using examples and comparative examples, but the present invention is not limited to these examples in any way.

[0031] The methods for measuring the physical properties of the chemical polishing solution, the physical properties of copper and copper alloys, the methods for evaluating the amount of dissolved copper or copper alloy in the surface-treated product, and the methods for evaluating unevenness in the treatment of the surface-treated product in the examples and comparative examples are as follows.

[0032] (1) pH measurement of chemical polishing solution The pH of the chemical polishing solution at 25° C. was measured using a pH meter (Horiba Ltd., product name "D-53") in accordance with JIS Z8802.

[0033] (2) Types of copper and copper alloys The following four types of copper or copper alloys were used: (a) Corson alloy (NKC-4419-H): 0.2 mm thick, 50 mm long x 30 mm wide (manufactured by Test Piece Co., Ltd.), Co: 1.9% by mass, Si: 0.44% by mass, Cu: balance (b) Pure copper: 0.2 mm thick, 50 mm long x 30 mm wide (manufactured by Test Piece Co., Ltd.), Cu: 100% by mass (c) Phosphor bronze: 0.2 mm thick, 50 mm long x 30 mm wide (manufactured by Test Piece 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 (d) Be bronze: 0.2 mm thick, 50 mm long x 30 mm wide (manufactured by Test Piece 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

[0034] (3) Evaluation of the amount of copper or copper alloy dissolved during surface treatment Copper or copper alloy pieces were immersed in a chemical polishing solution at a temperature of 30°C for 30 seconds. The immersed copper or copper alloy pieces were then removed from the chemical polishing solution, thoroughly rinsed with ion-exchanged water, and thoroughly dried to obtain surface-treated pieces. The amount of dissolved material was calculated from the weight loss before and after surface treatment using the following formula. Dissolution amount [μm] = (mass before treatment [g] - mass after treatment [g]) / (treated area of ​​copper or copper alloy piece [m 2 ]×8.92[g / cm 3 ](Copper specific gravity))

[0035] (4) Evaluation of unevenness in surface treatment The surface condition of the surface-treated products was visually observed and evaluated for the presence or absence of treatment unevenness. Figure 1 is a photograph showing an example of a product treated with a chemical polishing solution where color unevenness was observed. Figure 2 is a photograph showing an example of a product treated with a chemical polishing solution where color unevenness was not observed.

[0036] Example 1 (1) Preparation of chemical polishing solution A chemical polishing solution was prepared by mixing 1.6 parts by weight of hydrogen peroxide (60% by weight aqueous solution, manufactured by Mitsubishi Gas Chemical Company, Inc.) (active ingredient ratio as hydrogen peroxide, referred to as "hydrogen peroxide" in the Examples and Comparative Examples), 14.1 parts by weight of sulfuric acid (46% by weight aqueous solution, manufactured by Mitsubishi Gas Chemical Company, Inc.) (active ingredient ratio as sulfuric acid), 0.9 parts by weight of potassium fluoride (manufactured by Daiwa Chemical Industry Co., Ltd.) (0.4 parts by weight in terms of fluorine atoms), 0.09 parts by weight of anthranilic acid (manufactured by Mitsubishi Chemical Co., Ltd.), and 0.0018 parts by weight of the fluorosurfactant "Surflon S-243" (a fluorochemical nonionic surfactant having a perfluoroalkyl group, manufactured by AGC Seimi Chemical Co., Ltd.). Water was then added to make the total weight of the chemical polishing solution 83.3 parts by weight (the remainder).

[0037] (2) Surface treatment of copper and copper alloys The copper or copper alloy pieces were immersed in a chemical polishing solution at a liquid temperature of 30° C. for 30 seconds. Then, the immersed copper or copper alloy pieces were taken out of the chemical polishing solution, thoroughly washed with ion-exchanged water, and thoroughly dried to obtain surface-treated products. The amount of copper or copper alloy dissolved in the surface treatment and the evaluation results of the unevenness of the treatment on the surface-treated products are shown in Table 1-2.

[0038] Examples 2 to 12 A chemical polishing solution was prepared in the same manner as in Example 1, except that the composition of the chemical polishing solution was changed to that shown in Table 1-1, and surface treatment of copper and copper alloys was carried out. In Table 1-1, (A), (B), (C), (D), (E), and (F) respectively represent the above-mentioned components (A), (B), (C), (D), (E), and (F). The same applies to Tables 2 to 5. The amount of copper or copper alloy dissolved in the surface treatment and the evaluation results of the unevenness of the treatment on the surface-treated products are shown in Table 1-2.

[0039] [Table 1-1]

[0040] [Table 1-2]

[0041] Examples 13 to 15 A chemical polishing solution was prepared in the same manner as in Example 1, except that the composition of the chemical polishing solution was changed to that shown in Table 2, and surface treatment of copper and copper alloys was carried out using the chemical polishing solution. Table 2 shows the evaluation results of the amount of copper or copper alloy dissolved in the surface treatment and the unevenness of the treatment of the surface-treated product.

[0042] [Table 2]

[0043] Comparative Examples 1 to 15 A chemical polishing solution was prepared in the same manner as in Example 1, except that the composition of the chemical polishing solution was changed to that shown in Table 3, and surface treatment of copper and copper alloys was carried out using the chemical polishing solution. Table 3 shows the evaluation results of the amount of copper or copper alloy dissolved in the surface treatment and the unevenness of the treatment of the surface-treated product.

[0044] [Table 3]

[0045] Examples 16 to 21 Surface-treated products were obtained by changing the composition of the chemical polishing solution to that shown in Table 4. Specifically, a storage solution 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 solution. Copper and copper alloys were surface-treated in the same manner as in Example 1 to obtain surface-treated products. The evaluation results of the amount of copper or copper alloy dissolved in the surface treatment and the unevenness of the treatment on the surface-treated product are shown in Table 4. For comparison, Table 4 also shows the evaluation results of the amount of copper or copper alloy dissolved in the surface treatment on the surface on the chemical polishing solution having the same composition except that the storage solution was not stored at room temperature for 3 months, and the unevenness of the treatment on the surface-treated product. As shown in Table 4, when cyclohexylamine or cyclohexanol was used as component (D), it was found that the storage stability was also excellent.

[0046] [Table 4]

[0047] Example 22 The chemical polishing solution was prepared in the same manner as in Example 1, except that the composition of the chemical polishing solution was changed to that shown in Table 5 and that the copper alloy (NKC-4419-H) was dissolved in an amount of 5 g / L. The copper alloy (NKC-4419-H) was then surface-treated to obtain a surface-treated product. The results of evaluation of the amount of copper dissolved in the surface treatment and the unevenness of the treatment on the surface-treated product are shown in Table 5. For comparison, Table 5 also shows the amount of copper dissolved in the surface treatment and the unevenness of the treatment on the surface-treated product evaluated using the chemical polishing solution of Example 5, which has the same composition as Example 22 except that it does not dissolve the copper alloy (NKC-4419-H).

[0048] Comparative Examples 16 and 17 The composition of the chemical polishing solution was changed to that shown in Table 5, and in Comparative Example 17, a copper alloy (NKC-4419-H) was further dissolved in an amount of 5 g / L. Except for this, a chemical polishing solution was prepared in the same manner as in Example 1, and surface treatment of the copper alloy (NKC-4419-H) was performed to obtain a surface-treated product. Table 5 shows the evaluation results of the amount of copper dissolved in the surface treatment and the unevenness of the treatment on the surface-treated products.

[0049] [Table 5]

[0050] As shown in Table 5, by comparing the results of Comparative Examples 16 and 17, it was found that when component (E) was not added, uneven processing occurred during copper dissolution. By adding component (E), the chemical polishing solution of the present invention can suppress the occurrence of uneven processing even when the amount of copper dissolved in the solution increases, and a chemical polishing solution with stable removal performance can be provided.

Claims

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

2. 2. The chemical polishing solution according to claim 1, wherein the pH of the chemical polishing solution is 3 or less.

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

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

5. 5. The chemical polishing liquid according to claim 1, wherein the component (D) comprises at least one selected from the group consisting of cyclohexanol and cyclohexylamine.

6. 6. The chemical polishing liquid according to claim 1, wherein the component (E) comprises 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 contacting the surface of copper or a copper alloy with the chemical polishing liquid according to claim 1 to perform surface treatment of the copper or copper alloy.

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

9. 9. The surface treatment method according to claim 7, wherein the time for contacting the surface of the copper or copper alloy with the chemical polishing solution to perform the surface treatment of the copper or copper alloy is from 1 second to 10 minutes.

10. A method for producing a surface-treated copper or copper alloy, comprising contacting a surface of copper or a copper alloy with the chemical polishing liquid according to claim 1 to perform surface treatment of the copper or copper alloy.

11. 7. The method for producing a chemical polishing liquid according to claim 1, comprising uniformly stirring at least the component (A), the component (B), the component (C), the component (D), the component (E), and the component (F).

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