Catalyst additive solution for electroless plating, catalyst additive method, and electroless plating method.

Abstract

The invention relates to a catalyst addition solution which is useful for producing electroless plating films with excellent deposition properties and patterning properties on metallic materials. Specifically, the invention relates to a catalyst addition solution for electroless plating comprising (A) at least one cationic compound selected from the group of cationic polymers and cationic surfactants; and (B) a metal catalyst, wherein the metal catalyst (B) comprises at least one component selected from the group of Pd, Au, Ag, and Pt, the catalyst addition solution having a pH less than or equal to 5, the content of cationic compound (A) is from 0.01 mg / L to 1000 mg / L, and the content of metal catalyst (B) is from 0.01 mg / L to 100 mg / L.

Description

Electroless plating catalyst application solution, catalyst application method, and electroless plating method

[0001] The present invention relates to a catalyst application solution for electroless plating, a catalyst application method, and an electroless plating method.

[0002] In the field of electronics, such as printed wiring boards, semiconductor packages, and electronic components, one of the final processes during manufacturing is electroless plating of conductor circuits, terminal portions, etc. When electroless plating is performed on a metal material of a substrate, a catalyst application process is sometimes performed to deposit a metal catalyst, such as palladium, which serves as a catalyst nucleus, on the metal material by a substitution reaction in order to improve plating deposition properties, etc. (See, for example, Patent Document 1).

[0003] When performing electroless plating on a metal material such as a copper circuit, it is necessary to immerse the material to be plated in a catalyst application solution containing, for example, 10 to 100 mg / L of palladium. However, due to the recent rise in the price of metal catalysts such as palladium, there is a demand for lower concentrations of metal catalysts in catalyst application solutions.

[0004] JP 2011-058062 A

[0005] The present inventors have found that if the palladium concentration is reduced, sufficient catalytic nuclei are not formed on the copper circuit, and therefore the palladium does not function sufficiently as a catalyst for depositing electroless plating, resulting in a problem of reduced plating deposition properties.

[0006] Furthermore, the present inventors have found that, when the immersion time in the palladium catalyst application solution is extended in order to improve the deposition properties of the plating, it is possible to cause a sufficient amount of palladium catalyst to be adsorbed onto the copper circuit, but at the same time, the palladium catalyst also becomes more likely to be adsorbed onto the surface of the insulator, causing the plating to spread, making it difficult to obtain sufficient patterning.

[0007] As described above, in the case of a conventional catalyst application liquid, when the metal catalyst concentration in the catalyst application liquid is low, either the plating deposition property on the metal material or the plating patterning property is insufficient.

[0008] The present invention has been made in view of the current state of the prior art described above, and a main object of the present invention is to provide a catalyst imparting solution that is useful for forming an electroless plating film that has excellent plating deposition properties and patternability on a metal material.

[0009] The present inventors have conducted extensive research to achieve the above-mentioned object. As a result, they have found that an electroless plating film having excellent plating deposition properties and patternability on a metal material can be formed by using an electroless plating catalyst imparting solution containing (A) at least one cationic compound selected from the group consisting of a cationic polymer and a cationic surfactant, and (B) a metal catalyst. Based on this finding, the present inventors have conducted further research and have completed the present invention. That is, the present invention includes the following features.

[0010] Item 1. A catalyst application solution for electroless plating, comprising: (A) at least one cationic compound selected from the group consisting of a cationic polymer and a cationic surfactant; and (B) a metal catalyst, wherein the (B) metal catalyst comprises at least one selected from the group consisting of Pd, Au, Ag, and Pt, the pH is 5 or less, the content of the (A) cationic compound is 0.01 mg / L to 1000 mg / L, and the content of the (B) metal catalyst is 0.01 mg / L to 100 mg / L.

[0011] Item 2. The catalyst-imparting solution according to Item 1, wherein the (A) cationic compound includes at least one selected from the group consisting of polyethyleneimine, diallyldimethylammonium chloride sulfur dioxide copolymer, methyldiallylamine hydrochloride polymer, diallyldimethylammonium chloride polymer, dicyandiamide-polyalkylenepolyamine polycondensate, dicyandiamide-type cationic resin, allylamine hydrochloride-diallylamine hydrochloride polymer, allylamine hydrochloride polymer, allylamine polymer, O-[2-hydroxy-3-(trimethylammonio)propyl]hydroxyethyl cellulose chloride, polylysine, cationized guar gum, coconutamine acetate, tetradecylamine acetate, octadecylamine acetate, didecyldimethylammonium chloride, coconut alkyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, and stearyltrimethylammonium chloride.

[0012] Item 3. The catalyst imparting solution according to Item 1 or 2, wherein the metal catalyst (B) contains Pd.

[0013] Item 4. The catalyst application liquid according to any one of Items 1 to 3, further comprising (C) at least one acid selected from the group consisting of organic acids and inorganic acids.

[0014] Item 5. The catalyst-imparting solution according to Item 4, wherein the acid (C) includes at least one selected from the group consisting of acetic acid, malonic acid, succinic acid, adipic acid, maleic acid, fumaric acid, glycolic acid, lactic acid, malic acid, gluconic acid, hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, hydrofluoric acid, methanesulfonic acid, glutamic acid, aspartic acid, and boric acid.

[0015] Item 6. The catalyst-imparting solution according to any one of Items 1 to 5, further comprising (D) a chloride.

[0016] Item 7. The catalyst-imparting solution according to Item 6, wherein the (D) chloride includes at least one selected from the group consisting of potassium chloride, sodium chloride, ammonium chloride, calcium chloride, magnesium chloride, lithium chloride, trichloroacetaldehyde, and chlorine dioxide.

[0017] Item 8. The catalyst-imparting solution according to Item 6 or 7, wherein the content of the (D) chloride is 0.01 to 200 g / L.

[0018] Item 9. The catalyst application solution according to any one of Items 1 to 8, wherein the electroless plating is at least one selected from the group consisting of electroless palladium plating, electroless palladium alloy plating, electroless nickel plating, electroless nickel alloy plating, electroless silver plating, electroless silver alloy plating, electroless gold plating, and electroless gold alloy plating.

[0019] Item 10. The catalyst application liquid according to any one of Items 1 to 9, wherein the electroless plating is performed on a substrate having an insulating region and a conductive region on its surface.

[0020] Item 11. (1) A method for applying a catalyst for electroless plating, comprising a step of contacting an object to be plated with the catalyst application liquid according to any one of Items 1 to 10.

[0021] Item 12. An electroless plating method comprising the steps of: (1) contacting an object to be plated with the catalyst application liquid according to any one of Items 1 to 10; and (2) performing an electroless plating treatment.

[0022] Item 13. A substrate to which a catalyst has been applied by the catalyst application method according to Item 11.

[0023] Item 14. A substrate subjected to electroless plating treatment by the electroless plating method according to Item 12.

[0024] The electroless plating catalyst imparting solution of the present invention is useful for forming an electroless plating film having excellent plating deposition properties and patternability on a metal material.

[0025] In this specification, the expressions "contain" and "comprise" include any of "contain," "comprise," "consist only of," "consist essentially only of," and "consist only of."

[0026] In this specification, the expression "A to B" indicating a range of values ​​means "greater than or equal to A and less than or equal to B."

[0027] 1. Catalyst Application Solution The catalyst application solution for electroless plating of the present invention (hereinafter sometimes referred to as the "catalyst application solution of the present invention" or "catalyst application solution") contains (A) at least one cationic compound selected from the group consisting of a cationic polymer and a cationic surfactant (hereinafter sometimes simply referred to as "(A) cationic compound") and (B) a metal catalyst. The catalyst application solution of the present invention having the above configuration contains (A) at least one cationic compound selected from the group consisting of a cationic polymer and a cationic surfactant, in addition to (B) the metal catalyst. This allows for sufficient application of the catalyst to the surface of the substrate to be plated, thereby achieving excellent plating deposition properties. Furthermore, it is possible to suppress adsorption of the palladium catalyst to the surface of the insulator, thereby suppressing plating spreading, achieving sufficient patternability, and suppressing corrosion of the copper surface. The present invention will be described in detail below.

[0028] (A) Cationic Compound The (A) cationic compound is not particularly limited as long as it can be adsorbed onto the insulating part via electrostatic interaction. Specific examples of the (A) cationic compound include polyethyleneimine, diallyldimethylammonium chloride sulfur dioxide copolymer, methyldiallylamine hydrochloride polymer, diallyldimethylammonium chloride polymer, dicyandiamide-polyalkylene polyamine polycondensate, dicyandiamide-type cationic resin, allylamine hydrochloride-diallylamine hydrochloride polymer, allylamine hydrochloride polymer, allylamine polymer, O-[2-hydroxy-3-(trimethylammonio)propyl]hydroxyethyl cellulose chloride, polylysine, cationized guar gum, coconut amine acetate, tetradecylamine acetate, octadecylamine acetate, didecyldimethylammonium chloride, coconut alkyl trimethyl ammonium chloride, hexadecyl trimethyl ammonium chloride, and stearyl trimethyl ammonium chloride. Among these, from the viewpoint of forming an electroless plating film with excellent plating deposition properties and patterning properties on a metal material, cationic polymers are preferred, and diallyldimethylammonium chloride sulfur dioxide copolymer, methyldiallylamine hydrochloride polymer, diallyldimethylammonium chloride polymer, allylamine hydrochloride / diallylamine hydrochloride polymer, allylamine hydrochloride polymer, and allylamine polymer are more preferred.

[0029] Specific examples of the cationic compound (A) include compounds represented by the following general formula:

[0030] [In the formula, n represents an integer of 10 to 1500, l represents an integer of 1 or greater, and m represents an integer of 2 or greater. The upper limits of the numerical ranges of l and m are not particularly limited as long as they do not conflict with the numerical range of the preferred weight-average molecular weight of the cationic polymer described below. Furthermore, R represents an alkyl group having 8 to 18 carbon atoms.]

[0031] The molecular weight of the (A) cationic compound is not particularly limited. When the (A) cationic compound is a cationic polymer, the weight average molecular weight is preferably 1,000 to 1,000,000.

[0032] The cationic compound (A) can be used alone or in combination of two or more.

[0033] The content of the (A) cationic compound in the catalyst application solution of the present invention is 0.01 mg / L to 1000 mg / L. The catalyst application solution of the present invention, having the (A) cationic compound content within the above range, can suppress foaming of the plating solution and reduce production costs. From the viewpoint of forming an electroless plating film with better plating deposition properties and patternability on metal materials, the content of the (A) cationic compound is preferably 0.05 mg / L to 1000 mg / L, more preferably 0.1 mg / L to 1000 mg / L, and even more preferably 1 mg / L to 1000 mg / L.

[0034] (B) Metal Catalyst The metal contained in the (B) metal catalyst includes at least one metal selected from the group consisting of Pd, Au, Ag, and Pt. Among these, Pd is preferred from the viewpoint of forming an electroless plating film with excellent plating deposition properties and patternability on metal materials.

[0035] The metal catalyst (B) may be used alone or in combination of two or more.

[0036] The content of the (B) metal catalyst in the catalyst imparting solution of the present invention is 0.01 mg / L to 100 mg / L. From the viewpoint of forming an electroless plating film with superior plating deposition properties and patternability on a metal material, the content of the (B) metal catalyst is preferably 0.05 mg / L to 100 mg / L, and more preferably 0.1 mg / L to 100 mg / L. The catalyst imparting solution of the present invention can form an electroless plating film with superior plating deposition properties and patternability on a metal material even when the amount of metal catalyst used is small (for example, the content in the catalyst imparting solution is 20 mg / L or less), thereby reducing the cost of forming the electroless plating film.

[0037] From the viewpoint of forming an electroless plating film with more excellent plating deposition properties and patternability on a metal material, the content of the (B) metal catalyst in the catalyst application solution of the present invention is preferably 0.001 parts by mass to 100 parts by mass, more preferably 0.005 parts by mass to 50 parts by mass, and even more preferably 0.01 parts by mass to 10 parts by mass, relative to 1 part by mass of the (A) cationic compound.

[0038] In the catalyst application solution of the present invention, the (B) metal catalyst is preferably present in an ionic state. Furthermore, the (B) metal catalyst is preferably not in the form of a colloid. In this case, the (B) metal catalyst is prevented from being adsorbed onto the insulating regions of the substrate, and the (B) metal catalyst is more likely to be efficiently deposited by a substitution reaction on the conductive regions of the substrate, thereby forming an electroless plating film with superior plating deposition properties and patternability on the metal material.

[0039] (C) Acid The catalyst imparting solution of the present invention is preferably acidic. The acidic nature of the catalyst imparting solution of the present invention allows for more effective utilization of the cationicity of the (A) cationic compound, specifically, suppressing the (B) metal catalyst from being adsorbed (deposited) on an insulating material, thereby facilitating the formation of an electroless plating film with excellent plating deposition properties and patternability on a metal material. In this specification, "acidic" means a pH of less than 7, preferably a pH of 6.9 or less or 6.8 or less.

[0040] The pH of the catalyst application solution of the present invention is 5 or less. From the viewpoint of forming an electroless plating film that has excellent plating deposition properties and patternability on a metal material, the pH is preferably 3 or less, more preferably 1 or less. By having a pH of 5 or less, the catalyst application solution of the present invention can effectively utilize the cationicity of the (A) cationic compound, specifically, can suppress adsorption of the (B) metal catalyst onto an insulating material, and is therefore useful for forming an electroless plating film that has excellent plating deposition properties and patternability on a metal material.

[0041] From the viewpoint of making the catalyst application liquid of the present invention acidic as described above, the catalyst application liquid of the present invention may contain, in addition to the (A) cationic compound and the (B) metal catalyst, (C) at least one acid selected from the group consisting of organic acids and inorganic acids (also referred to herein simply as "(C) acid"). By containing the (C) acid, the catalyst application liquid of the present invention can effectively utilize the cationic property of the (A) cationic compound, specifically, can suppress adsorption of the (B) metal catalyst onto insulating regions, thereby facilitating the formation of an electroless plating film with excellent plating deposition properties and patternability on metal materials.

[0042] The acid (C) is not particularly limited as long as it is soluble in the catalyst-imparting solution. Specific examples of the acid (C) include acetic acid, malonic acid, succinic acid, adipic acid, maleic acid, fumaric acid, glycolic acid, lactic acid, malic acid, gluconic acid, hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, hydrofluoric acid, methanesulfonic acid, glutamic acid, aspartic acid, and boric acid. Among these, glycolic acid, sulfuric acid, hydrochloric acid, and methanesulfonic acid are preferred from the viewpoint of forming an electroless plating film that has excellent plating deposition properties and patternability on metal materials.

[0043] The (C) acid may be used alone or in combination of two or more.

[0044] When the acid (C) is contained, the content thereof is not particularly limited as long as the pH is within the above range.

[0045] (D) Chloride The catalyst imparting solution of the present invention may contain (D) chloride in addition to the above compounds. Normally, when a metal material is immersed in a catalyst imparting solution for a long period of time, corrosion due to the metal catalyst may occur. However, when the catalyst imparting solution of the present invention contains (D) chloride, it is possible to form an electroless plating film on the metal material that has excellent plating deposition properties and patternability while further suppressing corrosion of the metal material in the treatment process. Furthermore, when a catalyst imparting solution containing (D) chloride is used, the patternability of the electroless plating film on the metal material can be further improved compared to when (D) chloride is not used.

[0046] The (D) chloride is not particularly limited as long as it is soluble in the catalyst application liquid. Examples of the (D) chloride include potassium chloride, sodium chloride, ammonium chloride, calcium chloride, magnesium chloride, lithium chloride, trichloroacetaldehyde, and chlorine dioxide. Among these, sodium chloride, potassium chloride, and ammonium chloride are preferred from the viewpoint of forming an electroless plating film that is excellent in plating deposition property and patternability on metal materials.

[0047] The chlorides (D) may be used singly or in combination of two or more.

[0048] When the catalyst-imparting solution of the present invention contains (D) chloride, its content is not particularly limited, but is preferably 0.01 g / L to 200 g / L, more preferably 1 g / L to 100 g / L, and even more preferably 3 g / L to 50 g / L. If the chloride content is too high, the metal material itself becomes more likely to dissolve, which accelerates the progression of corrosion, or chlorides are formed on the metal material, which hinder the substitution reaction of the metal catalyst. If the chloride content is too low, the catalyst-imparting solution will contain insufficient chloride ions, making it difficult to sufficiently suppress corrosion of the metal material.

[0049] The catalyst imparting solution of the present invention preferably contains water as a main solvent. The catalyst imparting solution of the present invention may also contain a solvent other than water. The solvent other than water that can be contained in the catalyst imparting solution of the present invention is not particularly limited as long as it does not impair the effects of the present invention, and examples include alcohols such as methanol, ethanol, isopropanol, isobutanol, sec-butanol, tert-butanol, ethylene glycol, and glycerin; ethers such as ethylene glycol dimethyl ether, 1,4-dioxane, and tetrahydrofuran; and ketones such as acetone and methyl ethyl ketone. When a solvent other than water is contained, its content is not particularly limited, but is preferably 5% by mass or less, and more preferably 0.5% by mass or less, relative to 100% by mass of the solvent. When the upper limit of the content of the solvent other than water is within the above range, a decrease in the effect of the cationic compound due to the hydrophobicity of the solvent is further suppressed.

[0050] The catalyst imparting solution of the present invention may further contain various additives as required, such as stabilizers, pH buffers, surfactants, etc.

[0051] The stabilizer may be, for example, a lead salt such as lead nitrate or lead acetate; a bismuth salt such as bismuth nitrate or bismuth acetate; or a sulfur compound such as sodium thiosulfate, either singly or in combination. When a stabilizer is added, the amount added is not particularly limited, but may be, for example, about 0.01 mg / L to about 100 mg / L.

[0052] As the pH buffer, for example, acetic acid, boric acid, phosphoric acid, phosphorous acid, carbonic acid, phthalic acid, oxalic acid, or their sodium salts, potassium salts, ammonium salts, etc. may be added alone or in combination of two or more. When a pH buffer is added, the amount added is not particularly limited, but may be about 0.002 mol / L to 1 mol / L from the viewpoint of bath stability, etc.

[0053] In addition to the cationic surfactants described above, various surfactants such as nonionic, anionic, and amphoteric surfactants can be used as surfactants. Examples include aromatic or aliphatic alkali sulfonate salts, and aromatic or aliphatic alkali metal carboxylate salts. The surfactants can be used alone or in combination of two or more. When a surfactant is added, the amount added is not particularly limited, but can be, for example, about 0.01 mg / L to about 1000 mg / L.

[0054] The catalyst application solution of the present invention preferably does not contain a reducing agent. In this case, by suppressing colloid formation of the (B) metal catalyst, adsorption of the (B) metal catalyst onto insulating regions of the plated object is suppressed, and the (B) metal catalyst is more likely to be efficiently deposited by a substitution reaction onto conductive regions of the plated object, thereby forming an electroless plating film with superior plating deposition properties and patternability on the metal material.

[0055] 2. Catalyst Application Method In one aspect, the present invention relates to (1) a method for producing a material to be electrolessly plated containing catalytic nuclei, or a method for treating a material to be electrolessly plated with a catalyst, which comprises a step of contacting a substrate with the catalyst application solution of the present invention (sometimes referred to as "Method 1 of the present invention" in this specification). This will be described below.

[0056] The object to be plated is not particularly limited as long as it is a material having exposed metal on its surface, and may be made of, for example, glass fiber reinforced epoxy, polyimide, plastics such as PET, glass, ceramic, metal oxide, metal, paper, synthetic or natural fiber, or a combination of these materials, and may be in the form of a plate, film, cloth, fiber, tube, or the like.

[0057] Specific examples of the object to be plated include printed wiring boards, semiconductor packages, electronic components, ceramic substrates, etc. In these materials, the metal exposed on the surface can form wiring.

[0058] Examples of metals exposed on the surface include copper, copper alloys, nickel, nickel alloys, silver, silver alloys, gold, gold alloys, platinum, platinum alloys, molybdenum, tungsten, etc. Among these, copper alloys, silver alloys, gold alloys, and platinum alloys can be applied to alloys containing, for example, 50 mass % or more of copper, nickel, silver, gold, or platinum, respectively.

[0059] As described above, the object to be plated preferably has an insulating region and a conductive region on its surface. In this case, by Method 1 of the present invention, the (A) cationic compound is pre-adsorbed onto the insulating region, and part or all of the (B) metal catalyst used is efficiently deposited on the conductive region by a substitution reaction. That is, by Method 1 of the present invention, catalytic nuclei containing the (B) metal catalyst are efficiently formed on the conductive region (particularly the surface metal) of the object to be plated. Therefore, Method 1 of the present invention facilitates the formation of an electroless plating film with excellent patternability in the subsequent electroless plating treatment step while ensuring plating deposition properties on the metal material.

[0060] Method 1 of the present invention can provide a material to which such a catalyst has been applied, specifically, a substrate having an insulating region and a conductive region on its surface, and a material (substrate) having metal catalyst 1 on the conductive region, with adhesion of the metal catalyst 1 to the insulating region being suppressed. By subjecting an object to be plated, which is a material to which such a catalyst has been applied, to electroless plating, an electroless plating film with superior plating deposition properties and patternability (selective deposition properties) can be formed. The purpose of the catalyst core containing the metal catalyst is surface activation, and its thickness can be, for example, 0.05 μm or less, such as 0.005 μm to 0.05 μm.

[0061] The object to be plated is preferably subjected to pretreatment such as degreasing and soft etching.

[0062] The specific method for bringing the catalyst application solution of the present invention into contact with the object to be plated is not particularly limited, but typically involves immersing the object to be plated in the catalyst application solution of the present invention. Alternatively, the catalyst application treatment can be carried out by applying or spraying the catalyst application solution onto the surface of the object to be plated.

[0063] When the catalyst application liquid of the present invention is applied by the immersion method, the liquid temperature of the catalyst application liquid of the present invention is usually preferably about 10°C to 90°C, more preferably about 20°C to 40°C, and even more preferably 25°C to 35°C.

[0064] The treatment time is preferably about 10 seconds to 20 minutes, more preferably about 30 seconds to 5 minutes, and even more preferably 1 minute to 3 minutes.

[0065] 3. Electroless Plating Method In one aspect, the present invention relates to a method for producing a material including an electroless plated film or a method for electrolessly plating an object to be plated (sometimes referred to as "Method 2 of the present invention" in this specification), which comprises, in order, (1) a step of contacting an object to be plated with the catalyst application solution of the present invention, and (2) a step of electroless plating. This will be described below.

[0066] Step (1) is as described above in "2. Method for providing catalyst."

[0067] (2) The electroless plating treatment in the electroless plating treatment step can be carried out by bringing the material (subject to be plated) to which the catalyst obtained in step (1) has been applied into contact with an electroless plating solution.

[0068] Before the electroless plating treatment, the cationic compound (A) on the object to be plated may be partially or entirely removed by ordinary water washing treatment.

[0069] The electroless plating solution is not particularly limited, and an autocatalytic electroless plating solution can be used. For example, an electroless palladium plating solution, an electroless palladium alloy plating solution, an electroless copper plating solution, an electroless copper alloy plating solution, an electroless nickel plating solution, an electroless nickel alloy plating solution, an electroless silver plating solution, an electroless silver alloy plating solution, an electroless gold plating solution, an electroless gold alloy plating solution, etc. can be used. The specific composition of these electroless plating solutions is not particularly limited, and an autocatalytic electroless plating solution having a known composition containing a reducing agent component can be used. Plating conditions can also be in accordance with normal plating conditions depending on the type of plating solution used.

[0070] In step (2) of method 2 of the present invention, suitable electroless plating solutions include electroless palladium plating solution, electroless palladium alloy plating solution, electroless nickel plating solution, electroless nickel alloy plating solution, electroless silver plating solution, electroless silver alloy plating solution, electroless gold plating solution, and electroless gold alloy plating solution. When an electroless nickel plating solution or electroless nickel alloy plating solution is used in step (2), it is preferable to further perform electroless silver plating, electroless silver alloy plating, electroless gold plating, or electroless gold alloy plating. When an electroless nickel plating solution or electroless nickel alloy plating solution is used in step (2), it is preferable to further perform electroless palladium plating or electroless palladium alloy plating, and more preferably to further perform electroless gold plating or electroless gold alloy plating following this. When an electroless palladium plating solution or electroless palladium alloy plating solution is used in step (2), it is preferable to further perform electroless gold plating or electroless gold alloy plating. It is also possible to use only an electroless palladium plating solution, an electroless palladium alloy plating solution, an electroless nickel plating solution, an electroless nickel alloy plating solution, an electroless silver plating solution, an electroless silver alloy plating solution, an electroless gold plating solution, or an electroless gold alloy plating solution in step (2).

[0071] Method 2 of the present invention can form an electroless plating film with superior plating deposition properties and patternability (selective deposition properties). Method 2 of the present invention can provide a material that provides such an electroless plating film, specifically, a material (substrate) that has a base material with insulating and conductive regions on its surface, a metal catalyst 1 on the conductive regions, and a film 2 on the metal catalyst 1, in which formation of the metal catalyst 1 and / or the film 2 on the insulating regions is suppressed.

[0072] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0073] (Preparation of catalyst-imparting solution) The raw materials shown in Table 1 were added in order in the proportions shown in Table 1 to water as a solvent to prepare 500 mL of a catalyst-imparting solution for each of the Examples and Comparative Examples.

[0074] (Evaluation Tests) In the following evaluation tests, the object to be plated was pretreated (acid degreasing, soft etching), and then catalytic nuclei were formed on the metal surface using the catalyst application solution prepared above. This was followed by electroless nickel plating or electroless palladium plating, and finally electroless gold plating, in that order. Details of each treatment are as follows unless otherwise specified. A 1-minute rinse with running water was performed between each step.

[0075] (a) Acidic Degreasing The substrate was immersed in an acidic degreasing solution (trade name: ICP Clean S-135K) containing sulfuric acid and a surfactant at 40° C. for 5 minutes.

[0076] (b) Soft Etching The substrate was immersed in an aqueous solution containing 100 g / L of sodium persulfate and 10 mL / L of 98% sulfuric acid at room temperature for 1 minute.

[0077] (c) Catalyst Application Treatment The sample was immersed in the catalyst application solution under the conditions shown in Table 1. Specifically, the pH was 1 or less in Examples 1 to 41 and Comparative Examples 1 to 5, and 6.8 in Examples 42 to 48 and Comparative Example 6. The immersion time was 1 minute in Examples 1 to 34 and Comparative Examples 1 to 4, and 3 minutes in Examples 35 to 48 and Comparative Examples 5 and 6. The treatment temperature was 30°C in all catalyst application solutions.

[0078] (d-1) Electroless Nickel Plating The plated film was immersed in an electroless nickel plating solution (trade name: ICP Nicoron FPF, manufactured by Okuno Chemical Industries Co., Ltd.) at 84° C. for 25 minutes to obtain a plating film having a thickness of 4 μm.

[0079] (d-2) Electroless Palladium Plating The substrate was immersed in an electroless palladium plating solution (trade name: Top Pallas PD, manufactured by Okuno Chemical Industries Co., Ltd.) at 65° C. for 5 minutes to obtain a plating film having a thickness of 0.1 μm.

[0080] (e) Electroless Gold Plating The substrate was immersed in an electroless gold plating solution (trade name: Top Pallas AU, manufactured by Okuno Chemical Industries Co., Ltd.) at 80° C. for 1 minute to obtain a plating film having a thickness of 0.05 μm.

[0081] Test Example 1: Evaluation of plating deposition properties A BGA resin substrate having over-resist type micro copper pads (φ60-130 μm, 30 pads) on a resin base material was prepared as the object to be plated. Electroless plating was performed on the BGA resin substrate using the above-mentioned processing steps. After electroless plating, the micro pads were observed under a microscope (300x magnification) to check the state of electroless plating deposition. Evaluation was performed according to the following evaluation criteria. ◯: No undeposited deposits at all △: Slight undeposited deposits were observed ×: A large amount of undeposited deposits were observed

[0082] Test Example 2: Evaluation of Patternability A BGA resin substrate having fine wiring (L / S = 50 / 50 μm) on a resin base material was prepared as the object to be plated. Electroless plating was applied to the BGA resin substrate using the above-described processing steps. After electroless plating, the wiring pattern portion of L / S = 50 / 50 μm was observed under a microscope (1000x magnification) to check for the presence or absence of spreading of the electroless plating. Evaluation was made according to the following evaluation criteria: ◯: No plating spreading at all Δ: Slight plating spreading was observed ×: Numerous plating spreading occurred

[0083] The results are shown in Tables 1 to 7.

[0084]

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

Claims

1. An electroless plating catalyst imparting solution comprising: (A) at least one cationic compound selected from the group consisting of cationic polymers and cationic surfactants; and (B) a metal catalyst, wherein the (B) metal catalyst comprises at least one selected from the group consisting of Pd, Au, Ag, and Pt, the pH is 5 or less, the content of the (A) cationic compound is 0.01 mg / L to 1000 mg / L, and the content of the (B) metal catalyst is 0.01 mg / L to 100 mg / L.

2. The catalyst-imparting solution according to claim 1, wherein the (A) cationic compound comprises at least one selected from the group consisting of polyethyleneimine, diallyldimethylammonium chloride sulfur dioxide copolymer, methyldiallylamine hydrochloride polymer, diallyldimethylammonium chloride polymer, dicyandiamide-polyalkylenepolyamine polycondensate, dicyandiamide type cationic resin, allylamine hydrochloride-diallylamine hydrochloride polymer, allylamine hydrochloride polymer, allylamine polymer, O-[2-hydroxy-3-(trimethylammonio)propyl]hydroxyethylcellulose chloride, polylysine, cationized guar gum, coconut amine acetate, tetradecylamine acetate, octadecylamine acetate, didecyldimethylammonium chloride, coconut alkyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, and stearyltrimethylammonium chloride.

3. The catalyst imparting solution according to claim 1, wherein the metal catalyst (B) contains Pd.

4. The catalyst imparting solution according to claim 1, further comprising (C) at least one acid selected from the group consisting of organic acids and inorganic acids.

5. The catalyst imparting solution according to claim 4, wherein the acid (C) includes at least one selected from the group consisting of acetic acid, malonic acid, succinic acid, adipic acid, maleic acid, fumaric acid, glycolic acid, lactic acid, malic acid, gluconic acid, hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, hydrofluoric acid, methanesulfonic acid, glutamic acid, aspartic acid, and boric acid.

6. The catalyst imparting solution according to claim 1, further comprising (D) a chloride.

7. The catalyst imparting solution according to claim 6, wherein the (D) chloride comprises at least one selected from the group consisting of potassium chloride, sodium chloride, ammonium chloride, calcium chloride, magnesium chloride, lithium chloride, trichloroacetaldehyde, and chlorine dioxide.

8. The catalyst imparting solution according to claim 6, wherein the content of the chloride (D) is 0.01 g / L to 200 g / L.

9. The catalyst imparting solution according to claim 1, wherein the electroless plating is at least one selected from the group consisting of electroless palladium plating, electroless palladium alloy plating, electroless nickel plating, electroless nickel alloy plating, electroless silver plating, electroless silver alloy plating, electroless gold plating, and electroless gold alloy plating.

10. The catalyst imparting solution according to claim 1, wherein the electroless plating is performed on a substrate having an insulating region and a conductive region on its surface.

11. (1) A method for applying a catalyst for electroless plating, comprising the step of contacting an object to be plated with the catalyst application liquid according to any one of claims 1 to 10.

12. An electroless plating method comprising the steps of: (1) contacting an object to be plated with the catalyst imparting solution according to any one of claims 1 to 10; and (2) performing an electroless plating process.

13. A substrate to which a catalyst has been applied by the method for applying a catalyst according to claim 11.

14. A substrate that has been electrolessly plated by the electroless plating method according to claim 12.