Plating film for metal sintering bonding, method for manufacturing the same, and semiconductor mounting substrate

Abstract

A plating film suitable for metal sintering bonding is provided, having excellent heat resistance and cold / thermal shock resistance. (A) A plating film for metal sintering bonding having an electroless nickel-phosphorus plating film, wherein the phosphorus content of the electroless nickel-phosphorus plating film (A) is 4 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film.

Description

Technology Field

[0001] The present invention relates to a plating film, a method for manufacturing the same, and a semiconductor mounting substrate. Background Technology

[0002] Recently, next-generation power modules equipped with wide bandgap power semiconductor devices such as SiC and GaN are being used. Since these next-generation power modules are capable of operating in high-temperature environments of, for example, 200°C or higher, high heat resistance is required for surrounding components as well.

[0003] Conventionally, solder is used when bonding semiconductor devices to a substrate, but there is a problem that it has poor heat resistance and cold / thermal shock resistance.

[0004] Metal sintering using silver or copper particles is attracting attention as a joining technology to replace solder. However, in order to perform metal sintering, surface treatment of the joining material, such as a substrate, is required, and heat resistance is also required for the film formed by the surface treatment.

[0005] The inventors have discovered that electroless nickel alloy plating is suitable as a surface treatment for silver sintering or copper sintering. Examples of electroless nickel alloy plating include electroless nickel-phosphorus plating and electroless nickel-boron plating, and in particular, electroless nickel-phosphorus plating films have been put into practical use in a wide range of fields.

[0006] However, the commonly used electroless nickel-phosphorus plating film with a phosphorus content of 6 to 12 mass% (see Patent Document 1) has poor heat resistance and cold shock resistance, and cracks occur when used in high-temperature environments, so there is a problem that it cannot be used as a peripheral component of next-generation power modules. Prior art literature

[0007] Patent Document 1: Japanese Patent Publication No. 2023-090169 The problem to be solved

[0008] The present invention aims to provide a plating film that has excellent heat resistance and cold shock resistance and is suitable for metal sintering bonding. means of solving the problem

[0009] The inventors, having conducted repeated research to solve the above problem, discovered that the above objective can be achieved by (A) a plating film having an electroless nickel-phosphorus plating film, wherein (A) the phosphorus content of the electroless nickel-phosphorus plating film is within a specific range, and thus completed the present invention.

[0010] That is, the present invention relates to the following plating film, a method for manufacturing the same, and a semiconductor mounting substrate.

[0011] 1. (A) A plating film for metal sintering bonding having an electroless nickel-phosphorus plating film, wherein

[0012] The phosphorus content of the above (A) electroless nickel-phosphorus plating film is 4 mass% or less, with the electroless nickel-phosphorus plating film being 100 mass%.

[0013] A plating film for metal sintering bonding characterized by

[0014] 2. A plating film for metal sintering bonding described in claim 1, wherein the sulfur content of the above (A) electroless nickel-phosphorus plating film is less than 0.0005 mass% with respect to 100 mass% of the electroless nickel-phosphorus plating film.

[0015] 3. A plating film for metal sintering bonding described in claim 1 or 2, wherein the sulfur content of the electroless nickel-phosphorus plating film (A) is 0.0001 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film.

[0016] 4. A plating film for metal sintering bonding described in any one of claims 1 to 3, wherein the thickness of the electroless nickel-phosphorus plating film (A) above is 0.1 to 20 μm.

[0017] 5. A plating film for metal sintering bonding described in any one of claims 1 to 4, having (B) an electroless silver plating film or an electroless gold plating film on the above (A) electroless nickel-phosphorus plating film.

[0018] 6. A plating film for metal sintering bonding described in claim 5, wherein the thickness of the above (B) electroless silver plating film or electroless gold plating film is 0.02 to 2 μm.

[0019] 7. A plating film for metal sintering bonding described in claim 5 or 6, further having (C) a barrier metal layer between (A) the electroless nickel-phosphorus plating film and (B) the electroless silver plating film or the electroless gold plating film.

[0020] 8. The above (C) barrier metal layer is an electroless palladium plating film or an electroless palladium-phosphorus plating film, a plating film for metal sintering bonding as described in claim 7.

[0021] 9. A plating film for metal sintering bonding described in any one of claims 1 to 8, which is for metal sintering materials containing silver and / or copper.

[0022] 10. A method for manufacturing a plating film for metal sintering bonding, wherein a plating film for metal sintering bonding is formed on a substrate,

[0023] (1) A process 1 of contacting an electroless nickel-phosphorus plating solution with the surface of a substrate to form (A) an electroless nickel-phosphorus plating film on the substrate, and

[0024] The phosphorus content of the above (A) electroless nickel-phosphorus plating film is 4 mass% or less, with the electroless nickel-phosphorus plating film being 100 mass%.

[0025] A method for manufacturing a plating film for metal sintering bonding, characterized by the following.

[0026] 11. (2) A manufacturing method described in claim 10, further comprising process 2 of contacting an electroless silver plating solution or an electroless gold plating solution on the surface of the electroless nickel-phosphorus plating film to form (B) an electroless silver plating film or an electroless gold plating film on the (A) electroless nickel-phosphorus plating film.

[0027] 12. A plating film for metal sintering bonding having (A) an electroless nickel-phosphorus plating film is laminated on a substrate, and

[0028] A semiconductor device is provided by interposing a metal sintering layer on the above-mentioned plating film for metal sintering bonding, and

[0029] The phosphorus content of the above (A) electroless nickel-phosphorus plating film is 4 mass% or less, with the electroless nickel-phosphorus plating film being 100 mass%.

[0030] A semiconductor mounting substrate characterized by the following: Effects of the invention

[0031] The plating film for metal sintering bonding according to the present invention has excellent heat resistance and cold / thermal shock resistance. For this reason, it can be suitably used for metal sintering bonding in next-generation power modules. Furthermore, the method for manufacturing the plating film according to the present invention can produce a plating film that has excellent heat resistance and cold / thermal shock resistance and can be suitably used for metal sintering bonding. In addition, the semiconductor mounting substrate according to the present invention has excellent heat resistance and cold / thermal shock resistance. Specific details for implementing the invention

[0032] The present invention will be described in detail below.

[0033] In addition, in the plating film for metal sintering bonding according to the present invention, when (A) an electroless nickel-phosphorus plating film is laminated on a substrate, the direction of the side opposite to the side in contact with the substrate is referred to as the "upper" or "surface," and the direction of the opposite side, that is, the side of (A) the electroless nickel-phosphorus plating film in contact with the substrate, is referred to as the "lower" or "back side."

[0034] 1. Plating film for metal sintering bonding

[0035] The plating film for metal sintering bonding according to the present invention (hereinafter also simply referred to as "plating film") is a plating film having (A) an electroless nickel-phosphorus plating film (hereinafter also referred to as "layer (A)"), wherein the phosphorus content of the electroless nickel-phosphorus plating film (A) is 4 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film. Because the plating film of the present invention has the above layer (A), the layer (A) can suppress oxidation of the substrate, and can dissipate heat generated from the semiconductor device while fixing the semiconductor device through the metal sintering material, and is suitable for mounting the semiconductor device. In addition, since the phosphorus content of the layer (A) is 4 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film, the plating film of the present invention has excellent heat resistance and cold / thermal shock resistance, and can be suitably used for metal sintering bonding.

[0036] Hereinafter, each plating film constituting the plating film for metal sintering bonding of the present invention will be described in detail.

[0037] ((A) Electroless nickel-phosphorus plating film)

[0038] The plating film for metal sintering bonding of the present invention has (A) an electroless nickel-phosphorus plating film.

[0039] The phosphorus content of the electroless nickel-phosphorus plating film is 4 mass% or less, with the electroless nickel-phosphorus plating film being 100 mass%. If the phosphorus content exceeds 4 mass%, the heat resistance and cold / thermal shock resistance are inferior, and cracks occur in the plating film, resulting in insufficient bonding with the metal sintered material and making it unsuitable for mounting semiconductor devices. The phosphorus content is preferably 3 mass% or less, more preferably 2 mass% or less, and even more preferably 1 mass% or less. In addition, the lower limit of the phosphorus content is not particularly limited and may be 0.1 mass%, 0.2 mass%, or 0.5 mass%. The phosphorus content of the electroless nickel-phosphorus plating film can be reduced by changing the composition of the electroless nickel-phosphorus plating or the plating conditions.

[0040] (A) layer preferably has a sulfur content of less than 0.0005 mass% with respect to 100 mass% of (A) electroless nickel-phosphorus plating film, more preferably 0.0002 mass% or less, even more preferably 0.0001 mass% or less, and particularly preferably contains no sulfur and is 0 mass%. Since the sulfur content of (A) layer is within the above range, the heat resistance and cold / thermal shock resistance of the plating film of the present invention are further improved, and the occurrence of cracks can be suppressed, making it suitable for mounting semiconductor devices through metal sintered materials. The sulfur content can be reduced by reducing the raw material containing divalent sulfur in the composition of the electroless nickel-phosphorus plating solution for forming (A) layer.

[0041] (A) The thickness of the layer is not particularly limited, but is preferably 0.1 to 20 μm, more preferably 0.2 to 10 μm, and even more preferably 0.5 to 5 μm.

[0042] ((B) Electroless silver plating, or electroless gold plating)

[0043] The plating film for metal sintering bonding according to the present invention may have (B) an electroless silver plating film or an electroless gold plating film (hereinafter also referred to as “layer (B)”) on layer (A). By having layer (B) of the plating film for metal sintering bonding according to the present invention, the bonding performance with the metal sintering material is further improved, and heat generated from the semiconductor device can be dissipated while fixing the semiconductor device through the metal sintering material, making it more suitable for mounting the semiconductor device.

[0044] (B) The thickness of the layer is not particularly limited, but is preferably 0.02 to 2 μm from the perspective of being able to fix the semiconductor device more securely through the metal sintered material and also making it easier to dissipate heat generated from the semiconductor device while fixing the semiconductor device.

[0045] When layer (B) is an electroless silver plating film, the thickness of layer (B) is preferably 0.02 to 1 μm, and more preferably 0.05 to 0.5 μm. In addition, when layer (B) is an electroless gold plating film, the thickness of layer (B) is preferably 0.02 to 1 μm, and more preferably 0.03 to 0.2 μm.

[0046] ((C) Barrier metal layer)

[0047] The plating film for metal sintering bonding according to the present invention may further have a barrier metal layer (C) (hereinafter also referred to as “layer (C)”) between layer (A) and layer (B). Since the plating film for metal sintering bonding according to the present invention has layer (C), surface diffusion of the underlying metal and corrosion of the nickel-phosphorus plating film by electroless silver plating or electroless gold plating can be further suppressed, so the bonding performance with the metal sintering material is further improved.

[0048] (C) The layer is not particularly limited and may be any known plating film. Examples of the (C) layer include an electroless palladium plating film, an electroless palladium-phosphorus plating film, an electroless platinum plating film, an electroless cobalt-phosphorus plating film, an electroless cobalt-boron plating film, etc. Among these, an electroless palladium plating film and an electroless palladium-phosphorus plating film are preferred from the view that they can further suppress surface diffusion of the underlying metal and corrosion of the nickel-phosphorus plating film by electroless silver plating or electroless gold plating.

[0049] When the (C) layer contains phosphorus, such as in an electroless palladium-phosphorus plating film, the phosphorus content in the (C) layer is preferably 0.1 to 2.0 mass% with respect to 100 mass% of the (C) layer, and more preferably 0.5 to 1.5 mass%. By having the phosphorus content in the (C) layer within the above range, surface diffusion of the underlying metal and corrosion of the nickel-phosphorus plating film by electroless silver plating or electroless gold plating can be further suppressed.

[0050] (Characteristics of plating films for metal sintering bonding)

[0051] The thickness of the plating film for metal sintering bonding according to the present invention is not particularly limited, but is preferably 1 to 10 μm, more preferably 1.5 to 8 μm, and even more preferably 2 to 5 μm. By having the thickness of the plating film for metal sintering bonding within the above range, the mounted semiconductor can be fixed more firmly, and oxidation is further suppressed.

[0052] The plating film for metal sintering bonding of the present invention described above has excellent heat resistance and cold / thermal shock resistance due to the aforementioned composition. For this reason, it can be suitably used as a metal sintering bonding material for next-generation power modules. The plating film for metal sintering bonding of the present invention can be suitably used, in particular, for silver sintering bonding or copper sintering bonding. That is, the plating film for metal sintering bonding of the present invention is suitable for use as a metal sintering material containing silver and / or copper.

[0053] 2. Method for manufacturing a plating film for metal sintering bonding

[0054] The method for manufacturing a plating film for metal sintering bonding according to the present invention is a method for manufacturing a plating film for metal sintering bonding that forms a plating film for metal sintering bonding on a substrate, comprising: (1) a process 1 of contacting an electroless nickel-phosphorus plating solution with the surface of a substrate to form (A) an electroless nickel-phosphorus plating film on the substrate, wherein the phosphorus content of (A) the electroless nickel-phosphorus plating film is 4 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film. According to the method of the present invention, a plating film for metal sintering bonding according to the present invention can be manufactured that has excellent heat resistance and cold / thermal shock resistance and can be suitably used for metal sintering bonding.

[0055] The following describes each process.

[0056] (Process 1)

[0057] Process 1 is a process of contacting an electroless nickel-phosphorus plating solution with the surface of a substrate to form (A) an electroless nickel-phosphorus plating film on the substrate.

[0058] Examples of substrates (workpieces) used in Process 1 include substrates used for electronic components such as semiconductors and circuits. Examples of such substrates include printed circuit boards, ceramic substrates, silicon substrates, and metal substrates. Specifically, examples include semiconductor chips (mainly back electrodes) such as SiC, GaN, and Si, metal lead frames, insulating heat dissipation circuit boards (ceramic substrates) such as DBC (Direct Bonded Copper) substrates, DBA (Direct Bonded Aluminum) substrates, and AMB (Active Metal Brazing) substrates, and heat dissipation substrates such as heat sinks. Examples of materials for the plated portion of the workpiece include copper, copper alloys, aluminum, and aluminum alloys.

[0059] The electroless nickel-phosphorus plating solution used in Process 1 is not particularly limited as long as the phosphorus content of the electroless nickel-phosphorus plating film produced in Process 1 can be adjusted to 4 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film. Examples of such an electroless nickel-phosphorus plating solution include, for instance, an electroless nickel-phosphorus plating solution containing a water-soluble nickel compound, a reducing agent, and a complexing agent, and, if necessary, other additives. Below, such an electroless nickel-phosphorus plating solution will be described by example.

[0060] (Water-soluble nickel compound)

[0061] The water-soluble nickel compound included in the electroless nickel-phosphorus plating solution used in the manufacturing method of the present invention is not particularly limited, and any known nickel compound used in electroless nickel-phosphorus plating solutions may be used. The water-soluble nickel compound is preferably, for example, a water-soluble nickel inorganic salt such as nickel sulfate, nickel chloride, nickel hypophosphorusate, nickel carbonate; a water-soluble nickel organic salt such as nickel acetate, nickel malate, etc., and their hydrates.

[0062] Water-soluble nickel compounds may be used as a single type or in combination of two or more types.

[0063] The concentration of the water-soluble nickel compound in the electroless nickel-phosphorus plating solution is not particularly limited and can be appropriately adjusted as long as it is within a range capable of forming an electroless nickel-phosphorus plating film. The concentration of the water-soluble nickel compound is preferably, for example, about 0.01 g / L to 100 g / L as nickel metal, more preferably 0.5 g / L to 50 g / L, and even more preferably 1 g / L to 10 g / L. Since the deposition rate may slow down if the concentration of the water-soluble nickel compound is less than 0.01 g / L as nickel metal, and bath stability may decrease if it exceeds 100 g / L, it is preferable to keep it within the above range.

[0064] (reducing agent)

[0065] It is preferable that the reducing agent be at least one selected from the group consisting of hypophosphoric acid and hypophosphoric acid (e.g., sodium salt, potassium salt, ammonium salt, etc.).

[0066] The reducing agent may be used as a single type or in combination of two or more types.

[0067] The concentration of a reducing agent (hypophosphorus acid, hypophosphorus salt, and its hydrate, etc.) in an electroless nickel-phosphorus plating solution is preferably about 0.5 g / L to 40 g / L, more preferably about 1 g / L to 20 g / L, and even more preferably about 2 g / L to 15 g / L. Since the upper limit of the concentration is within the above range, it becomes easier to adjust the phosphorus content of the formed electroless nickel-phosphorus plating film to 4 mass% or less. In addition, since the lower limit of the concentration is within the above range, the precipitation properties of the electroless nickel-phosphorus plating can be made more stable.

[0068] (Ignition agent)

[0069] The electroless nickel-phosphorus plating solution preferably includes glycine, gluconate, etc. as a complexing agent. The gluconate is preferably, for example, a sodium salt, a potassium salt, an ammonium salt, etc.

[0070] Other complexing agents are preferably monocarboxylic acids such as formic acid and acetic acid or their salts (e.g., sodium salt, potassium salt, ammonium salt, etc.); dicarboxylic acids such as malonic acid, succinic acid, adipic acid, maleic acid, fumaric acid or their salts (e.g., sodium salt, potassium salt, ammonium salt, etc.); hydroxycarboxylic acids such as malic acid, lactic acid, glycolic acid, and citric acid or their salts (e.g., sodium salt, potassium salt, ammonium salt, etc.); ethylenediaminediacetic acid, ethylenediaminetetraacetic acid or their salts (e.g., sodium salt, potassium salt, ammonium salt, etc.); amino acids such as alanine and arginine, etc.

[0071] The fire starter may be used as a single type or in combination of two or more types.

[0072] The concentration of the complexing agent in the electroless nickel-phosphorus plating solution is not particularly limited and can be appropriately adjusted. The electroless nickel-phosphorus plating solution preferably contains about 1 g / L to 100 g / L of the complexing agent, more preferably about 2 g / L to 50 g / L, and even more preferably about 5 g / L to 30 g / L. Since bath stability may decrease if the concentration of the complexing agent is less than 1 g / L and the deposition rate may decrease if it exceeds 100 g / L, it is preferable to keep it within the above range.

[0073] (Stabilizers, sulfur-based additives, pH adjusters, surfactants, etc.)

[0074] In addition to the aforementioned components, the above-mentioned electroless nickel-phosphorus plating solution may incorporate known additives used in electroless nickel-phosphorus plating solutions as needed. Examples of such additives include stabilizers, sulfur-based additives, pH adjusters, surfactants, etc.

[0075] Stabilizers include, for example, lead compounds (e.g., lead nitrate, lead acetate, etc.), cadmium compounds (e.g., cadmium nitrate, cadmium acetate, etc.), thallium compounds (e.g., thallium sulfate, thallium nitrate, etc.), antimony compounds (e.g., antimony chloride, potassium antimonyl tartrate, etc.), tellurium compounds (e.g., telluric acid, tellurium chloride, etc.), chromium compounds (e.g., chromium oxide, chromium sulfate, etc.), iron compounds (e.g., iron sulfate, iron chloride, etc.), manganese compounds (e.g., manganese sulfate, manganese nitrate, etc.), bismuth compounds (e.g., bismuth nitrate, bismuth acetate, etc.), tin compounds (e.g., tin sulfate, tin chloride, etc.), selenium compounds (e.g., selenic acid, selenic acid, etc.), cyanides (e.g., methyl cyanide, isopropyl cyanide, etc.), Examples include iodine compounds (e.g., potassium iodide, etc.).

[0076] Stabilizers may be used as a single type or in combination of two or more types.

[0077] The concentration of the stabilizer in the electroless nickel-phosphorus plating solution is not particularly limited and can be, for example, approximately 0.1 mg / L to 500 mg / L. For the purpose of improving the stability of the electroless nickel-phosphorus plating solution, it is desirable to set the concentration of the stabilizer to approximately 0.1 mg / L or higher. Since areas where the plating film is not formed (areas of non-precipitation) may occur if the concentration of the stabilizer exceeds 500 mg / L, it is desirable to keep it within the above range.

[0078] Preferably, a divalent sulfur compound, such as thiourea, is used as the sulfur additive. In order to further reduce the sulfur content of the electroless nickel-phosphorus plating film, it is desirable to use the minimum necessary amount or not add any at all.

[0079] The pH adjuster preferably uses an acid, such as hydrochloric acid, sulfuric acid, or phosphoric acid; or an alkali, such as sodium hydroxide, potassium hydroxide, or ammonia water.

[0080] The pH of the electroless nickel-phosphorus plating solution is preferably about 3 to 12, and more preferably about 4 to 9. The pH of the plating bath can be adjusted using the pH adjusting agent mentioned above. Since incomplete precipitation may occur if the pH is less than 3 and bath stability may decrease if it exceeds 12, it is preferable to keep it within the above range.

[0081] As surfactants, various types of surfactants such as nonionic, anionic, cationic, and amphoteric surfactants may be used. Examples include alkali salts of aromatic or aliphatic sulfonates, and alkali metal salts of aromatic or aliphatic sulfonates. Surfactants may be used individually or in a mixture of two or more types. When two or more surfactants are mixed, the mixing ratio is not particularly limited and can be appropriately determined.

[0082] The concentration of the surfactant in the electroless nickel-phosphorus plating solution is not particularly limited and can be, for example, 0.01 mg / L to 1000 mg / L. In order to further improve the pitting prevention effect of the electroless nickel-phosphorus plating solution, it is desirable to set the concentration of the surfactant to 0.01 mg / L or higher. If the concentration of the surfactant is 1000 mg / L or lower, the decrease in precipitation due to foaming is further suppressed.

[0083] (Electroless nickel-phosphorus plating method)

[0084] In process 1, the electroless nickel-phosphorus plating solution is brought into contact with the surface of the substrate.

[0085] The method of contacting the surface of a substrate with an electroless plating solution is not particularly limited and can be carried out according to conventional methods. In process 1, preferably, for example, a method of immersing the substrate to be plated in an electroless nickel-phosphorus plating solution may be used.

[0086] As for the plating treatment conditions (e.g., liquid temperature, plating treatment time, etc.), they are not particularly limited and can be appropriately determined as long as they are conditions under which an electroless nickel-phosphorus plating film is formed.

[0087] The liquid temperature of the electroless nickel-phosphorus plating solution in Process 1 can be appropriately determined according to the composition of the electroless nickel-phosphorus plating solution, etc. For example, the liquid temperature of the electroless nickel-phosphorus plating solution in the plating process can preferably be about 25°C or higher, more preferably about 40°C to 100°C, and even more preferably about 45°C to 95°C. Since the deposition rate of the plating film is slow if the liquid temperature is less than 25°C, which may result in a decrease in production efficiency, it is desirable to keep it within the above range.

[0088] The processing time in Process 1 is not particularly limited and can be the time required for an electroless plating film of the required thickness to be formed on the workpiece. Specifically, the processing time in the plating process can be appropriately determined according to the composition of the plating bath, the type of workpiece, etc., and, for example, can be preferably 1 minute to 120 minutes, more preferably 3 minutes to 60 minutes.

[0089] The electroless nickel-phosphorus plating film formed on the substrate by process 1 is the (A) electroless nickel-phosphorus plating film having the plating film for metal sintering bonding of the present invention, and the phosphorus content is 4 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film. The characteristics, etc. for the (A) electroless nickel-phosphorus plating film formed on the substrate by process 1 are the same as the characteristics, etc. described for the (A) electroless nickel-phosphorus plating film in the plating film for metal sintering bonding of the present invention.

[0090] (A) As a method for adjusting the phosphorus content in the electroless nickel-phosphorus plating film to 4 mass% or less, (i) a method of adjusting the content of the reducing agent in the electroless nickel-phosphorus plating solution may be cited. If the content of the reducing agent in the electroless nickel-phosphorus plating solution increases, the phosphorus content of the formed electroless nickel-phosphorus plating film increases, and if the content of the reducing agent in the electroless nickel-phosphorus plating solution decreases, the phosphorus content of the electroless nickel-phosphorus plating film decreases. In addition, as a method of the above adjustment, (ii) a method of adjusting the pH of the electroless nickel-phosphorus plating solution in Process 1 may be cited. If the pH is lowered, the phosphorus content of the formed electroless nickel-phosphorus plating film increases, and if the pH is raised, the phosphorus content of the electroless nickel-phosphorus plating film decreases. In addition, as a method of the above adjustment, (iii) a method of adjusting the liquid temperature of the electroless nickel-phosphorus plating solution in Process 1 may be cited. When the liquid temperature increases, the phosphorus content of the formed electroless nickel-phosphorus plating film decreases, and when the liquid temperature decreases, the phosphorus content of the electroless nickel-phosphorus plating film increases.

[0091] (A) As a method for adjusting the sulfur content in an electroless nickel-phosphorus plating film, one method is to adjust the content of divalent sulfur compounds, such as thiourea, in the electroless nickel-phosphorus plating solution. When the content of divalent sulfur compounds in the electroless nickel-phosphorus plating solution increases, the sulfur content of the formed electroless nickel-phosphorus plating film increases, and when the content of divalent sulfur compounds in the electroless nickel-phosphorus plating solution decreases, the sulfur content of the electroless nickel-phosphorus plating film decreases.

[0092] By the above-described process 1, (A) an electroless nickel-phosphorus plating film is formed on the substrate.

[0093] (Process 2)

[0094] The manufacturing method of the present invention may further include, after process 1, process 2, (2) contacting an electroless silver plating solution or an electroless gold plating solution to the surface of the electroless nickel-phosphorus plating film to form (B) an electroless silver plating film or an electroless gold plating film on the (A) electroless nickel-phosphorus plating film.

[0095] The electroless silver plating solution or electroless gold plating solution used in Process 2 is not particularly limited and conventionally known solutions may be used. Below, the electroless silver plating solution and electroless gold plating solution used in Process 2 will be described.

[0096] [Electroless Silver Plating Solution]

[0097] The electroless silver plating solution is not particularly limited, and, for example, a reduction precipitation type, a substitution reduction precipitation type, or a substitution precipitation type electroless silver plating solution may be used. As a reduction precipitation type or a substitution reduction precipitation type electroless silver plating solution, an electroless silver plating solution containing a silver compound, a reducing agent, and a complexing agent, and containing other additives as needed, may be used. Furthermore, as a substitution precipitation type electroless silver plating solution, an electroless silver plating solution containing a silver compound and a complexing agent, and containing other additives as needed, may be used. Below, such electroless silver plating solutions are described by example.

[0098] (Silver compound)

[0099] As for the silver compound, it is not particularly limited as long as it is a water-soluble silver compound, and known silver compounds used in electroless silver plating solutions may be used. Examples of silver compounds include inorganic salts such as silver nitrate, silver sulfate, and silver iodide; and organic acid salts such as silver acetate and silver methanesulfonic acid.

[0100] Silver compounds may be used as a single type or in combination of two or more types.

[0101] The concentration of the silver compound in the electroless silver plating solution is not particularly limited and can be appropriately adjusted as long as it is within a range capable of forming an electroless silver plating film. The concentration of the silver compound is preferably, as silver metal, about 0.01 g / L to 20 g / L, more preferably 0.1 to 10 g / L, and even more preferably 0.2 g / L to 5 g / L. Since the deposition rate may slow down if the concentration of the silver compound as silver metal is less than 0.01 g / L, and bath stability may decrease if it exceeds 20 g / L, it is preferable to keep it within the above range.

[0102] (reducing agent)

[0103] Preferably, the reducing agent is at least one selected from the group consisting of water-soluble aldehyde compounds, water-soluble hydrazine derivatives, boron hydride compounds, hypophosphorous acid, phosphoric acid, ascorbic acid, and salts thereof (e.g., sodium salt, potassium salt, ammonium salt, etc.). In addition, in the case of a substitutional precipitation type electroless silver plating solution, it is not necessary to contain a reducing agent.

[0104] The reducing agent may be used as a single type or in combination of two or more types.

[0105] The concentration of the reducing agent in the electroless silver plating solution is preferably about 0.5 g / L to 15 g / L, more preferably about 1 g / L to 13 g / L, and even more preferably about 1.5 g / L to 10 g / L.

[0106] (Ignition agent)

[0107] The electroless silver plating solution preferably includes, as a complexing agent, an amide compound, an imide compound, a thiosulfate compound, a sulfite compound, a sulfur-containing compound (a sulfur-containing compound other than a thiosulfate compound or a sulfite compound), a nitrogen-containing compound (a nitrogen-containing compound other than an amide compound or an imide compound), and more preferably includes an amide compound or an imide compound.

[0108] Examples of amide compounds include cyclic amide compounds such as benzamide, N-methylpyrrolidone, N-ethylpyrrolidone, N-vinylpyrrolidone, pyrrolidone, N-butylpyrrolidone, 5-methylpyrrolidone, and N-methylpiperidinone; and chain-like amide compounds such as acetamide, formamide, N,N-dimethylformamide, N-methyl-N-phenylformamide, and N,N-diphenylformamide. These may be used individually or in combination of two or more. Among these, chain-like amide compounds are preferred, and acetamide and formamide are more preferred.

[0109] As for the imide compound, it is not particularly limited, and cyclic imide compounds such as hydantoin, 5,5-dimethylhydantoin, 1-methylhydantoin, 1,3-dimethylhydantoin, glutarimide, and succinimide are preferred, hydantoin, 5,5-dimethylhydantoin, 1-methylhydantoin, succinimide, 1,3-methylhydantoin, and glutarimide are more preferred, and 1-methylhydantoin and succinimide are even more preferred.

[0110] The fire starter may be used as a single type or in combination of two or more types.

[0111] The concentration of the complexing agent in the electroless silver plating solution is not particularly limited and can be appropriately adjusted. The electroless silver plating solution preferably contains about 1 g / L to 100 g / L of the complexing agent, more preferably about 2 g / L to 50 g / L, and even more preferably about 5 g / L to 30 g / L. Since bath stability may decrease if the concentration of the complexing agent is less than 1 g / L and the deposition rate may decrease if it exceeds 100 g / L, it is desirable to keep it within the above range.

[0112] (Stabilizers, pH adjusters, surfactants, etc.)

[0113] In addition to the aforementioned components, the above-mentioned electroless silver plating solution may contain known additives used in electroless silver plating solutions as needed. Examples of additives include stabilizers, pH adjusters, surfactants, etc.

[0114] Stabilizers include, for example, lead compounds (e.g., lead nitrate, lead acetate, etc.), cadmium compounds (e.g., cadmium nitrate, cadmium acetate, etc.), thallium compounds (e.g., thallium sulfate, thallium nitrate, etc.), antimony compounds (e.g., antimony chloride, potassium antimonyl tartrate, etc.), tellurium compounds (e.g., telluric acid, tellurium chloride, etc.), chromium compounds (e.g., chromium oxide, chromium sulfate, etc.), iron compounds (e.g., iron sulfate, iron chloride, etc.), manganese compounds (e.g., manganese sulfate, manganese nitrate, etc.), bismuth compounds (e.g., bismuth nitrate, bismuth acetate, etc.), tin compounds (e.g., tin sulfate, tin chloride, etc.), selenium compounds (e.g., selenic acid, selenic acid, etc.), cyanides (e.g., methyl cyanide, isopropyl cyanide, etc.), Examples include iodine compounds (e.g., potassium iodide, etc.).

[0115] Stabilizers may be used as a single type or in combination of two or more types.

[0116] The concentration of the stabilizer in the electroless silver plating solution is not particularly limited and can be, for example, approximately 0.1 mg / L to 500 mg / L. For the purpose of improving the stability of the electroless silver plating solution, it is desirable to set the concentration of the stabilizer to approximately 0.1 mg / L or higher. Since areas where the plating film is not formed (areas of non-precipitation) may occur if the concentration of the stabilizer exceeds 500 mg / L, it is desirable to keep it within the above range.

[0117] The pH adjuster preferably uses an acid, such as nitric acid, sulfuric acid, or phosphoric acid; or an alkali, such as sodium hydroxide, potassium hydroxide, or ammonia water.

[0118] The pH of the electroless silver plating solution is preferably about 1 to 12, and more preferably about 1.5 to 11. The pH of the plating bath can be adjusted using the pH adjusting agent mentioned above. Since incomplete precipitation may occur if the pH is less than 1 and bath stability may decrease if it exceeds 12, it is preferable to keep it within the above range.

[0119] As surfactants, various types of surfactants such as nonionic, anionic, cationic, and amphoteric surfactants may be used. Examples include alkali salts of aromatic or aliphatic sulfonates, and alkali metal salts of aromatic or aliphatic sulfonates. Surfactants may be used individually or in a mixture of two or more types. When two or more surfactants are mixed, the mixing ratio is not particularly limited and can be appropriately determined.

[0120] The concentration of the surfactant in the electroless silver plating solution is not particularly limited and can be, for example, 0.01 mg / L to 1000 mg / L. In order to further improve the pitting prevention effect of the electroless silver plating solution, it is desirable to set the concentration of the surfactant to 0.01 mg / L or higher. If the concentration of the surfactant is 1000 mg / L or lower, the decrease in precipitation due to foaming is further suppressed.

[0121] (Electroless silver plating method)

[0122] In process 2, the method of forming an electroless silver plating film on an electroless nickel-phosphorus plating film is not particularly limited, and a method of contacting an electroless silver plating solution with the surface of the electroless nickel-phosphorus plating film formed in process 1 may be used.

[0123] The method of contacting the surface of the electroless nickel-phosphorus plating film with the electroless silver plating solution is not particularly limited and can be carried out according to conventional methods. In process 2, preferably, for example, a method of immersing a substrate on which an electroless nickel-phosphorus plating film is formed in the electroless silver plating solution may be used.

[0124] As for the plating treatment conditions (e.g., liquid temperature, plating treatment time, etc.), they are not particularly limited and can be appropriately determined as long as they are conditions under which an electroless silver plating film is formed.

[0125] The liquid temperature of the electroless silver plating solution in process 2 can be appropriately determined according to the composition of the electroless silver plating solution, etc. For example, the liquid temperature of the electroless silver plating solution in the plating process can preferably be about 25°C or higher, more preferably about 30°C to 80°C, and even more preferably about 40°C to 75°C. Since the deposition rate of the plating film is slow if the liquid temperature is below 25°C, which may lead to a decrease in production efficiency, it is desirable to keep it within the above range.

[0126] The processing time in process 2 is not particularly limited and can be the time required to form an electroless silver plating film of the required thickness. Specifically, the processing time in the plating process can be appropriately determined according to the composition of the electroless silver plating solution, and for example, preferably 1 minute to 40 minutes, more preferably 3 minutes to 20 minutes.

[0127] The electroless silver plating film formed by process 2 is an electroless silver plating film as a (B) layer that may be present in the plating film for metal sintering bonding of the present invention. The characteristics of the electroless silver plating film formed on the substrate by process 2 are the same as the characteristics described as a (B) layer in the plating film for metal sintering bonding of the present invention.

[0128] [Electroless Gold Plating Solution]

[0129] The electroless gold plating solution is not particularly limited, and, for example, an electroless gold plating solution of the reduction precipitation type, substitution reduction precipitation type, or substitution precipitation type may be used. As an electroless gold plating solution of the reduction precipitation type or substitution reduction precipitation type, an electroless gold plating solution containing a gold compound, a reducing agent, and a complexing agent, and containing other additives as needed, may be used. Furthermore, as an electroless gold plating solution of the substitution precipitation type, an electroless gold plating solution containing a gold compound and a complexing agent, and containing other additives as needed, may be used. Below, such electroless gold plating solutions will be described by example.

[0130] (Gold compounds)

[0131] As for the gold compound, any known gold compound used in electroless gold plating solutions may be used, provided that it is a water-soluble gold compound. Examples of gold compounds include potassium gold sulfite, sodium gold sulfite, ammonium gold sulfite, potassium gold cyanide, sodium gold cyanide, ammonium gold cyanide, etc.

[0132] Gold compounds may be used as a single type or in combination of two or more types.

[0133] The concentration of the gold compound in the electroless gold plating solution is not particularly limited and can be appropriately adjusted as long as it is within a range capable of forming an electroless gold plating film. The concentration of the gold compound is preferably, as gold metal, about 0.01 g / L to 10 g / L, more preferably 0.2 g / L to 5 g / L, and even more preferably 0.5 g / L to 2 g / L. Since the deposition rate may slow down if the concentration of the gold compound as gold metal is less than 0.01 g / L, and costs increase if it exceeds 10 g / L, it is preferable to keep it within the above range.

[0134] (reducing agent)

[0135] The reducing agent is not particularly limited, and the same reducing agent used in known electroless gold plating solutions may be used. For example, hydrazines such as hydrated hydrazine, hydrazine sulfate, neutral hydrazine sulfate, hydrazine maleate, and their salts; hydroxylamines and their salts; hydrazine derivatives such as adipyrate dihydrazide, isophthalate dihydrazide, and isopropylhydrazine sulfate; ascorbic acid and its salts (sodium, potassium, ammonium salts, etc.); boron hydride compounds such as trimethylamineborane (TMAB) and dimethylamineborane (DMAB); thiourea; hypophosphorous acid and its salts (sodium, potassium, ammonium salts, etc.) may be used.

[0136] The reducing agent may be used as a single type or in combination of two or more types. In addition, in the case of a displacement precipitation type electroless gold plating solution, it may not contain a reducing agent.

[0137] The concentration of the reducing agent in the electroless gold plating solution is preferably about 1 g / L to 15 g / L, more preferably about 2 g / L to 13 g / L, and even more preferably about 3 g / L to 10 g / L.

[0138] (Ignition agent)

[0139] The complexing agent is not particularly limited, and any complexing agent used in known electroless gold plating solutions may be used. For example, sulfites such as sodium sulfite, potassium sulfite, and ammonium sulfite; cyanides such as sodium cyanide and potassium cyanide; thiosulfates such as sodium thiosulfate, potassium thiosulfate, and ammonium thiosulfate; inorganic acids such as phosphoric acid and boric acid, and their salts (sodium salt, potassium salt, ammonium salt, etc.); hydroxycarboxylic acids such as citric acid, gluconic acid, tartaric acid, lactic acid, and malic acid, and their salts (sodium salt, potassium salt, ammonium salt, etc.); amine compounds such as ethylenediamine and triethanolamine; aminocarboxylic acids such as glycine, alanine, ethylenediaminetetraacetic acid, and nitrilotriacetic acid, and their salts (sodium salt, potassium salt, ammonium salt, etc.); Phosphonic acids such as aminotrimethylenephosphonic acid, 1-hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetramethylenephosphonic acid, and diethylenetriaminepenta(methylenephosphonic acid), and their salts (sodium salt, potassium salt, ammonium salt, etc.) can be used.

[0140] The fire starter may be used as a single type or in combination of two or more types.

[0141] The concentration of the complexing agent in the electroless gold plating solution is not particularly limited and can be appropriately adjusted. The electroless gold plating solution preferably contains about 1 g / L to 100 g / L of the complexing agent, more preferably about 2 g / L to 50 g / L, and even more preferably about 5 g / L to 30 g / L. Since bath stability may decrease if the concentration of the complexing agent is less than 1 g / L and the deposition rate may decrease if it exceeds 100 g / L, it is desirable to keep it within the above range.

[0142] (Stabilizers, pH adjusters, surfactants, etc.)

[0143] In addition to the aforementioned components, the above-mentioned electroless gold plating solution may incorporate known additives used in electroless gold plating solutions as needed. Examples of such additives include stabilizers, pH adjusters, surfactants, etc.

[0144] Stabilizers include, for example, lead compounds (e.g., lead nitrate, lead acetate, etc.), cadmium compounds (e.g., cadmium nitrate, cadmium acetate, etc.), thallium compounds (e.g., thallium sulfate, thallium nitrate, etc.), antimony compounds (e.g., antimony chloride, potassium antimonyl tartrate, etc.), tellurium compounds (e.g., telluric acid, tellurium chloride, etc.), chromium compounds (e.g., chromium oxide, chromium sulfate, etc.), iron compounds (e.g., iron sulfate, iron chloride, etc.), manganese compounds (e.g., manganese sulfate, manganese nitrate, etc.), bismuth compounds (e.g., bismuth nitrate, bismuth acetate, etc.), tin compounds (e.g., tin sulfate, tin chloride, etc.), selenium compounds (e.g., selenic acid, selenic acid, etc.), cyanides (e.g., methyl cyanide, isopropyl cyanide, etc.), Examples include iodine compounds (e.g., potassium iodide, etc.).

[0145] Stabilizers may be used as a single type or in combination of two or more types.

[0146] The concentration of the stabilizer in the electroless gold plating solution is not particularly limited and can be, for example, approximately 0.1 mg / L to 500 mg / L. For the purpose of improving the stability of the electroless gold plating solution, it is desirable to set the concentration of the stabilizer to approximately 0.1 mg / L or higher. Since areas where the plating film is not formed (areas of non-precipitation) may occur if the concentration of the stabilizer exceeds 500 mg / L, it is desirable to keep it within the above range.

[0147] The pH adjuster preferably uses an acid, such as hydrochloric acid, sulfuric acid, or phosphoric acid; or an alkali, such as sodium hydroxide, potassium hydroxide, or ammonia water.

[0148] The pH of the electroless gold plating solution is preferably about 3 to 12, and more preferably about 4 to 9. The pH of the plating bath can be adjusted using the pH adjusting agent mentioned above. Since a pH of less than 3 may result in incomplete precipitation and a pH of more than 12 may reduce bath stability, it is desirable to keep the pH within the above range.

[0149] As surfactants, various types of surfactants such as nonionic, anionic, cationic, and amphoteric surfactants may be used. Examples include alkali salts of aromatic or aliphatic sulfonates, and alkali metal salts of aromatic or aliphatic sulfonates. Surfactants may be used individually or in a mixture of two or more types. When two or more surfactants are mixed, the mixing ratio is not particularly limited and can be appropriately determined.

[0150] The concentration of the surfactant in the electroless gold plating solution is not particularly limited and can be, for example, 0.01 mg / L to 1000 mg / L. In order to further improve the pitting prevention effect of the electroless gold plating solution, it is desirable to set the concentration of the surfactant to 0.01 mg / L or higher. If the concentration of the surfactant is 1000 mg / L or lower, the decrease in precipitation due to foaming is further suppressed.

[0151] (Electroless gold plating method)

[0152] In process 2, the method of forming an electroless gold plating film on an electroless nickel-phosphorus plating film is not particularly limited, and a method of contacting an electroless gold plating solution with the surface of the electroless nickel-phosphorus plating film formed in process 1 may be used.

[0153] The method of contacting the surface of an electroless nickel-phosphorus plating film with an electroless gold plating solution is not particularly limited and can be carried out according to conventional methods. In process 2, preferably, for example, a method of immersing a substrate on which an electroless nickel-phosphorus plating film is formed in an electroless gold plating solution may be used.

[0154] As for the plating treatment conditions (e.g., liquid temperature, plating treatment time, etc.), they are not particularly limited and can be appropriately determined as long as they are conditions under which an electroless gold plating film is formed.

[0155] The liquid temperature of the electroless gold plating solution in process 2 can be appropriately determined according to the composition of the electroless gold plating solution, etc. For example, the liquid temperature of the electroless gold plating solution in the plating process can preferably be about 25°C or higher, more preferably about 40°C to 90°C, and even more preferably about 45°C to 85°C. Since the deposition rate of the plating film is slow if the liquid temperature is below 25°C, which may lead to a decrease in production efficiency, it is desirable to keep it within the above range.

[0156] The processing time in process 2 is not particularly limited and can be the time until an electroless gold plating film of the required thickness is formed. Specifically, the processing time in the plating process can be appropriately determined according to the composition of the electroless gold plating solution, and for example, preferably 1 minute to 40 minutes, more preferably 3 minutes to 20 minutes.

[0157] The electroless gold plating film formed by process 2 is an electroless gold plating film as a (B) layer that may be present in the plating film for metal sintering bonding of the present invention. The characteristics of the electroless gold plating film formed by process 2 are the same as the characteristics described as a (B) layer in the plating film for metal sintering bonding of the present invention.

[0158] By the above-described process 2, (A) an electroless silver plating film or an electroless gold plating film is formed on the electroless nickel-phosphorus plating film.

[0159] (Barrier metal layer formation process)

[0160] In the manufacturing method of the present invention, between processes 1 and 2, a barrier metal layer forming process may also be included, wherein a plating solution for forming a barrier metal layer is brought into contact with the surface of the electroless nickel-phosphorus plating film, thereby forming a barrier metal layer (C) on the electroless nickel-phosphorus plating film (A). By including the barrier metal layer forming process, a barrier metal layer (C) can be formed between layer (A) and layer (B).

[0161] (C) As a barrier metal layer, any known plating film may be used, and is not particularly limited. Examples of the (C) layer include an electroless palladium plating film, an electroless palladium-phosphorus plating film, an electroless platinum plating film, an electroless cobalt-phosphorus plating film, an electroless cobalt-boron plating film, etc. Among these, an electroless palladium plating film and an electroless palladium-phosphorus plating film are preferred from the view that they can further suppress surface diffusion of the underlying metal and corrosion of the electroless nickel-phosphorus plating film by electroless silver plating or electroless gold plating.

[0162] Hereinafter, an electroless palladium plating solution and an electroless palladium-phosphorus plating solution for forming an electroless palladium plating film and an electroless palladium-phosphorus plating film as a barrier metal layer will be described.

[0163] [Electroless Palladium Plating Solution, Electroless Palladium-Phosphorus Plating Solution]

[0164] Examples of electroless palladium plating solutions and electroless palladium-phosphorus plating solutions include, for instance, electroless palladium plating solutions and electroless palladium-phosphorus plating solutions containing a palladium compound, a reducing agent, and a complexing agent, and, if necessary, other additives. Below, electroless palladium plating solutions and electroless palladium-phosphorus plating solutions will be described by example.

[0165] (Palladium compound)

[0166] As for the palladium compound, it is not particularly limited as long as it is a water-soluble palladium compound, and known palladium compounds used in electroless palladium plating solutions and electroless palladium-phosphorus plating solutions may be used. Examples of palladium compounds include palladium chloride, palladium sulfate, palladium acetate, tetraammine palladium dichloride, etc.

[0167] Palladium compounds may be used as a single type or in combination of two or more types.

[0168] The concentration of the palladium compound in the electroless palladium plating solution and the electroless palladium-phosphorus plating solution is not particularly limited and can be appropriately adjusted as long as it is within a range capable of forming the plating film. The concentration of the palladium compound is preferably, as palladium metal, about 0.01 g / L to 10 g / L, more preferably 0.2 g / L to 5 g / L, and even more preferably 0.5 g / L to 2 g / L. Since the deposition rate may slow down if the concentration of the palladium compound as palladium metal is less than 0.01 g / L, and bath stability may decrease if it exceeds 10 g / L, it is preferable to keep it within the above range.

[0169] (reducing agent)

[0170] As a reducing agent used in an electroless palladium plating solution, it is preferable to use formic acid, a water-soluble aldehyde compound, a water-soluble hydrazine derivative, or a boron hydride compound. In addition, as a reducing agent used in an electroless palladium-phosphorus plating solution, it is preferable to use at least one selected from the group consisting of hypophosphorous acid and hypophosphorus salts (e.g., sodium salt, potassium salt, ammonium salt, etc.) and phosphorous acid and phosphorus salts (e.g., sodium salt, potassium salt, ammonium salt, etc.).

[0171] The reducing agent may be used as a single type or in combination of two or more types.

[0172] The concentration of the reducing agent in the electroless palladium plating solution and the electroless palladium-phosphorus plating solution is preferably about 1 g / L to 100 g / L, more preferably about 2 g / L to 50 g / L, and even more preferably about 5 g / L to 40 g / L.

[0173] (Ignition agent)

[0174] The complexing agent is not particularly limited, and any complexing agent used in known electroless palladium plating solutions and electroless palladium-phosphorus plating solutions may be used. As a complexing agent, for example, amines such as ethylenediamine and diethylenetriamine; aminopolycarboxylic acids such as ethylenediaminediacetic acid, ethylenediaminetetraacetic acid, and diethylenetriaminepentaacetic acid, or salts thereof (e.g., sodium salt, potassium salt, ammonium salt, etc.); amino acids such as glycine, alanine, iminodiacetic acid, nitrilotriacetic acid, L-glutamic acid, L-glutamic acid-diacetic acid, L-aspartic acid, and taurine, or salts thereof (e.g., sodium salt, potassium salt, ammonium salt); aminotrimethylenephosphonic acid, 1-hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetramethylenephosphonic acid, or salts thereof (e.g., sodium salt, potassium salt, ammonium salt); monocarboxylic acids such as acetic acid, or salts thereof (e.g., sodium salt, potassium salt, ammonium salt, etc.); Dicarboxylic acids such as malonic acid, succinic acid, adipic acid, maleic acid, fumaric acid, or their salts (e.g., sodium salt, potassium salt, ammonium salt, etc.); hydroxycarboxylic acids such as malic acid, lactic acid, glycolic acid, citric acid, or their salts (e.g., sodium salt, potassium salt, ammonium salt, etc.) may be used.

[0175] The fire starter may be used as a single type or in combination of two or more types.

[0176] The concentration of the complexing agent in the electroless palladium plating solution and the electroless palladium-phosphorus plating solution is not particularly limited and can be appropriately adjusted. The electroless palladium plating solution and the electroless palladium-phosphorus plating solution preferably contain about 1 g / L to 100 g / L of the complexing agent, more preferably about 2 g / L to 50 g / L, and even more preferably about 5 g / L to 30 g / L. Since bath stability may decrease if the concentration of the complexing agent is less than 1 g / L and the deposition rate may decrease if it exceeds 100 g / L, it is preferable to keep it within the above range.

[0177] (Stabilizers, pH adjusters, surfactants, etc.)

[0178] In addition to the aforementioned components, the above-mentioned electroless palladium plating solution and electroless palladium-phosphorus plating solution may, if necessary, incorporate known additives used in electroless palladium plating solutions and electroless palladium-phosphorus plating solutions. Examples of such additives include stabilizers, pH adjusters, surfactants, etc.

[0179] Stabilizers include, for example, lead compounds (e.g., lead nitrate, lead acetate, etc.), cadmium compounds (e.g., cadmium nitrate, cadmium acetate, etc.), thallium compounds (e.g., thallium sulfate, thallium nitrate, etc.), antimony compounds (e.g., antimony chloride, potassium antimonyl tartrate, etc.), tellurium compounds (e.g., telluric acid, tellurium chloride, etc.), chromium compounds (e.g., chromium oxide, chromium sulfate, etc.), iron compounds (e.g., iron sulfate, iron chloride, etc.), manganese compounds (e.g., manganese sulfate, manganese nitrate, etc.), bismuth compounds (e.g., bismuth nitrate, bismuth acetate, etc.), tin compounds (e.g., tin sulfate, tin chloride, etc.), selenium compounds (e.g., selenic acid, selenic acid, etc.), cyanides (e.g., methyl cyanide, isopropyl cyanide, etc.), Examples include iodine compounds (e.g., potassium iodide, etc.).

[0180] Stabilizers may be used as a single type or in combination of two or more types.

[0181] The concentration of the stabilizer in the electroless palladium plating solution and the electroless palladium-phosphorus plating solution is not particularly limited and can be, for example, 0.1 mg / L to 500 mg / L. For the purpose of improving the stability of the electroless palladium plating solution and the electroless palladium-phosphorus plating solution, it is preferable to set the concentration of the stabilizer to 0.1 mg / L or higher. Since areas where the plating film is not formed (areas of non-precipitation) may occur if the concentration of the stabilizer exceeds 500 mg / L, it is preferable to keep it within the above range.

[0182] The pH adjuster preferably uses an acid, such as hydrochloric acid, sulfuric acid, or phosphoric acid; or an alkali, such as sodium hydroxide, potassium hydroxide, or ammonia water.

[0183] The pH of the electroless palladium plating solution and the electroless palladium-phosphorus plating solution is preferably about 3 to 12, and more preferably about 4 to 9. The pH of the plating bath can be adjusted using the pH adjusting agent mentioned above. Since incomplete precipitation may occur if the pH is less than 3 and bath stability may decrease if it exceeds 12, it is preferable to keep it within the above range.

[0184] As surfactants, various types of surfactants such as nonionic, anionic, cationic, and amphoteric surfactants may be used. Examples include alkali salts of aromatic or aliphatic sulfonates, and alkali metal salts of aromatic or aliphatic sulfonates. Surfactants may be used individually or in a mixture of two or more types. When two or more surfactants are mixed, the mixing ratio is not particularly limited and can be appropriately determined.

[0185] The concentration of the surfactant in the electroless palladium plating solution and the electroless palladium-phosphorus plating solution is not particularly limited and can be, for example, 0.01 mg / L to 1000 mg / L. In order to further improve the pitting prevention effect of the electroless palladium plating solution and the electroless palladium-phosphorus plating solution, it is preferable to set the concentration of the surfactant to 0.01 mg / L or higher. If the concentration of the surfactant is 1000 mg / L or lower, the decrease in precipitation due to foaming is further suppressed.

[0186] (Method for forming a barrier metal layer)

[0187] In the process of forming a barrier metal layer, the method of forming, for example, an electroless palladium plating film and an electroless palladium-phosphorus plating film on an electroless nickel-phosphorus plating film is not particularly limited, and a method of contacting an electroless palladium plating solution and an electroless palladium-phosphorus plating solution with the surface of the electroless nickel-phosphorus plating film formed in process 1 may be used.

[0188] The method of contacting the surface of the electroless nickel-phosphorus plating film with the electroless palladium plating solution and the electroless palladium-phosphorus plating solution is not particularly limited and can be carried out according to conventional methods. In the barrier metal layer formation process, preferably, for example, a method of immersing a substrate on which an electroless nickel-phosphorus plating film is formed in the electroless palladium plating solution and the electroless palladium-phosphorus plating solution may be used.

[0189] As for the plating treatment conditions (e.g., liquid temperature, plating treatment time, etc.), they are not particularly limited and can be appropriately determined as long as they are conditions under which an electroless palladium plating layer and an electroless palladium-phosphorus plating layer are formed.

[0190] The liquid temperature of the electroless palladium plating solution and the electroless palladium-phosphorus plating solution in the barrier metal layer formation process can be appropriately determined according to the composition of the electroless palladium plating solution and the electroless palladium-phosphorus plating solution. For example, the liquid temperature of the electroless palladium plating solution and the electroless palladium-phosphorus plating solution in the plating process can preferably be about 25°C or higher, more preferably about 40°C to 90°C, and even more preferably about 45°C to 85°C. Since the deposition rate of the plating film is slow if the liquid temperature is less than 25°C, which may lead to a decrease in production efficiency, it is desirable to keep it within the above range.

[0191] The processing time in the barrier metal layer formation process is not particularly limited and can be the time required to form an electroless palladium plating layer or an electroless palladium-phosphorus plating layer of the required film thickness. Specifically, the processing time in the plating process can be appropriately determined according to the composition of the electroless palladium plating solution or the electroless palladium-phosphorus plating solution. For example, it can preferably be about 1 minute to 40 minutes, and more preferably 3 minutes to 20 minutes.

[0192] The electroless palladium plating film and the electroless palladium-phosphorus plating film formed by the barrier metal layer formation process are barrier metal layers that may be provided as (C) layers in the plating film for metal sintering bonding of the present invention. The characteristics of the barrier metal layer formed by the barrier metal layer formation process are identical to the characteristics described as (C) layers in the plating film for metal sintering bonding of the present invention.

[0193] By the barrier metal layer formation process described above, a barrier metal layer (C) is formed on the electroless nickel-phosphorus plating film (A). By having the barrier metal layer formation process, a barrier metal layer (C) can be formed between layer (A) and layer (B).

[0194] 3. Semiconductor Mounting Board

[0195] The semiconductor mounting substrate of the present invention has a semiconductor device having a metal sintering bonding plating film (A) having an electroless nickel-phosphorus plating film laminated on a substrate, and a metal sintering material layer interposed on the metal sintering bonding plating film, wherein the phosphorus content of the electroless nickel-phosphorus plating film (A) is 4 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film.

[0196] The semiconductor mounting substrate of the present invention has a plating film for metal sintering bonding of the present invention formed thereon on the substrate, and a semiconductor device is bonded thereto by interposing a metal sintering layer on the plating film for metal sintering bonding.

[0197] The characteristics of the plating film for metal sintering bonding are the same as the characteristics described in the description of the plating film for metal sintering bonding of the present invention above.

[0198] In the semiconductor mounting substrate of the present invention, the semiconductor device is bonded by interposing a metal sintered layer.

[0199] As a sintering material for forming a metal sintering layer, a sintering paste comprising metal powder and an organic solvent can be used.

[0200] The metal powder included in the sintered material paste is not particularly limited, and known metal powders used in conventional sintered materials may be used. Examples of such metals include silver, copper, and gold, and among these, copper and silver powders are preferred, and silver powder is more preferred.

[0201] The average particle diameter of the metal powder is not particularly limited, and metal powder of known sizes can be used. The average particle diameter of the metal powder is preferably on the order of several μm to mm.

[0202] The organic solvent included in the sintered material paste is not particularly limited, and known organic solvents used in conventional sintered material pastes may be used. Examples of such organic solvents include methanol, ethanol, 1-propanol, 2-propanol, 2-butanol, 1-butanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 1-pentanol, 1-octanol, toluene, diethylene glycol, triethylene glycol, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, diethylene glycol monohexyl ether, terpineol, diethylene glycol methyl ether acetate terpineol, diisopropyl ether, tetrahydrofuran, 1,4-dioxane, etc. Among these, toluene, diethylene glycol, triethylene glycol, diethylene glycol monomethyl ether, terpineol, diethylene glycol methyl ether acetate terpineol, etc. can be suitably used.

[0203] The heating temperature during metal sintering bonding is not particularly limited, and the heating temperature used when performing metal sintering bonding normally is acceptable, and is approximately 100 to 450°C.

[0204] The pressure during metal sintering bonding may be either no pressure or pressure. In the case of pressure, the pressure is preferably about 0.1 MPa to 50 MPa, and more preferably about 0.2 MPa to 5 MPa.

[0205] As a configuration of the semiconductor mounting substrate of the present invention, at least on the substrate, a plating film for metal sintering bonding having (A) an electroless nickel-phosphorus plating film is laminated, and a semiconductor device is provided by interposing a metal sintering layer on the plating film for metal sintering bonding. That is, as a configuration of the semiconductor mounting substrate of the present invention, it is preferable to have at least a substrate / plating film for metal sintering bonding / metal sintering layer / semiconductor device, but it is also preferable to have a configuration that further includes a plating film for metal sintering bonding on the semiconductor device side. That is, as a configuration of the semiconductor mounting substrate of the present invention, it may have a substrate / plating film for metal sintering bonding / metal sintering layer / plating film for metal sintering bonding / semiconductor device, and more specifically, it may have a substrate / layer (A) / metal sintering layer / layer (A) / semiconductor device.

[0206] The semiconductor mounting substrate of the present invention has excellent heat resistance and cold / thermal shock resistance because a plating film for metal sintering bonding of the present invention is formed on the substrate, and a semiconductor device is bonded to the plating film for metal sintering bonding with a metal sintering layer interposed therebetween. Such a semiconductor mounting substrate of the present invention can be suitably utilized as a next-generation power module capable of operating in a high-temperature environment.

[0207] The plating film for metal sintering bonding according to the present invention has excellent heat resistance and cold shock resistance due to the aforementioned composition. For this reason, it can be suitably used for metal sintering bonding and can also be used to form a bonded body between a substrate (e.g., an insulating heat dissipation circuit board such as a DBC substrate or DBA substrate) and a substrate (e.g., a heat sink). As a composition of such a bonded body, examples include a substrate (e.g., an insulating heat dissipation circuit board such as a DBC substrate or DBA substrate) / plating film for metal sintering bonding / metal sintering layer / plating film for metal sintering bonding / substrate (e.g., a heat sink).

[0208] Examples

[0209] The present invention will be explained in more detail below by presenting examples and comparative examples. However, the present invention is not limited to the examples.

[0210] In addition, in each example and comparative example, a copper bulk material (30×30×3 mm) was used as the substrate (to be plated). The substrate was pretreated by degreasing and acid activation treatment, and by applying a palladium catalyst.

[0211] (Example 1) Workpiece: Electroless nickel-phosphorus plating Film: Electroless silver plating Film

[0212] Formation of an electroless nickel-phosphorus plating film

[0213] The workpiece was brought into contact with an electroless nickel-phosphorus plating solution of the following formulation under the following plating conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0214] Formulation of electroless nickel-phosphorus plating

[0215] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 20 g / L of sodium hypophosphite, 20 g / L of glycine, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0216] Conditions for electroless nickel-phosphorus plating

[0217] Liquid temperature: 90℃

[0218] Contact time with plating solution: 20 minutes

[0219] Formation of an electroless silver plating film

[0220] An electroless nickel-phosphorus plating film formed on a workpiece was brought into contact with an electroless silver plating solution of the following formulation under the following plating conditions to form an electroless silver plating film on the electroless nickel-phosphorus plating film.

[0221] Formulation of electroless silver plating

[0222] As a basic composition, 1.7 g / L silver nitrate, 1.5 g / L water-soluble hydrazine derivative, 20 g / L 1-methylhydantoin, and 0.5 mg / L lead acetate were combined, and after adding other trace additives, the pH was adjusted to 10 using nitric acid and sodium hydroxide.

[0223] Conditions for electroless silver plating

[0224] Liquid temperature: 60℃

[0225] Contact time with plating solution: 20 minutes

[0226] According to the above, a plating film for metal sintering bonding was manufactured in which the following electroless nickel-phosphorus plating film and electroless silver plating film were formed in this order on a workpiece.

[0227] · Electroless nickel-phosphorus plating: Phosphorus content 4 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0228] · Electroless silver plating: Thickness 0.2 µm

[0229] (Example 2) Workpiece: Electroless nickel-phosphorus plating Film: Electroless silver plating Film

[0230] By changing the composition and plating conditions of the electroless nickel-phosphorus plating of Example 1 as follows, a plating film for metal sintering bonding was prepared in which the following electroless nickel-phosphorus plating film and electroless silver plating film were formed in this order on the workpiece.

[0231] Formulation of electroless nickel-phosphorus plating

[0232] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 10 g / L of sodium hypophosphite, 20 g / L of glycine, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0233] Conditions for electroless nickel-phosphorus plating

[0234] Liquid temperature: 90℃

[0235] Contact time with plating solution: 25 minutes

[0236] · Electroless nickel-phosphorus plating: Phosphorus content 2 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0237] · Electroless silver plating: Thickness 0.2 µm

[0238] (Example 3) Workpiece: Electroless nickel-phosphorus plating Film: Electroless silver plating Film

[0239] By changing the composition and plating conditions of the electroless nickel-phosphorus plating of Example 1 as follows, a plating film for metal sintering bonding was prepared in which the following electroless nickel-phosphorus plating film and electroless silver plating film were formed in this order on the workpiece.

[0240] Formulation of electroless nickel-phosphorus plating

[0241] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 8 g / L of sodium hypophosphite, 20 g / L of glycine, and 0.5 mg / L of lead acetate were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0242] Conditions for electroless nickel-phosphorus plating

[0243] Liquid temperature: 90℃

[0244] Contact time with plating solution: 25 minutes

[0245] · Electroless nickel-phosphorus plating: Phosphorus content 2 mass%, sulfur content 0.0001 mass%, thickness 4 µm

[0246] · Electroless silver plating: Thickness 0.2 µm

[0247] (Example 4) Workpiece: Electroless nickel-phosphorus plating Film: Electroless silver plating Film

[0248] By changing the composition and plating conditions of the electroless nickel-phosphorus plating of Example 1 as follows, a plating film for metal sintering bonding was prepared in which the following electroless nickel-phosphorus plating film and electroless silver plating film were formed in this order on the workpiece.

[0249] Formulation of electroless nickel-phosphorus plating

[0250] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 8 g / L of sodium hypophosphite, 20 g / L of glycine, and 0.5 mg / L of lead acetate were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0251] Conditions for electroless nickel-phosphorus plating

[0252] Liquid temperature: 90℃

[0253] Contact time with plating solution: 3.5 minutes

[0254] · Electroless nickel-phosphorus plating: Phosphorus content 2 mass%, sulfur content 0.0001 mass%, thickness 0.5 µm

[0255] · Electroless silver plating: Thickness 0.2 µm

[0256] (Example 5) Workpiece: Electroless nickel-phosphorus plating Film: Electroless silver plating Film

[0257] By changing the composition and plating conditions of the electroless silver plating of Example 2 as follows, a plating film for metal sintering bonding was prepared in which the following electroless nickel-phosphorus plating film and electroless silver plating film were formed in this order on the workpiece.

[0258] Formulation of electroless silver plating

[0259] As a basic composition, 1.7 g / L silver nitrate, 1.5 g / L water-soluble hydrazine derivative, 20 g / L 1-methylhydantoin, and 0.5 mg / L lead acetate were combined, and after adding other trace additives, the pH was adjusted to 10 using nitric acid and sodium hydroxide.

[0260] Conditions for electroless silver plating

[0261] Liquid temperature: 60℃

[0262] Contact time with plating solution: 10 minutes

[0263] · Electroless nickel-phosphorus plating: Phosphorus content 2 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0264] · Electroless silver plating film: Thickness 0.1 µm

[0265] (Example 6) Workpiece: Electroless nickel-phosphorus plating Film: Electroless gold plating Film

[0266] Formation of an electroless nickel-phosphorus plating film

[0267] The workpiece was brought into contact with an electroless nickel-phosphorus plating solution of the following formulation under the following plating conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0268] Formulation of electroless nickel-phosphorus plating

[0269] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 20 g / L of sodium hypophosphite, 20 g / L of glycine, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0270] Conditions for electroless nickel-phosphorus plating

[0271] Liquid temperature: 90℃

[0272] Contact time with plating solution: 20 minutes

[0273] Formation of an electroless gold plating film

[0274] An electroless nickel-phosphorus plating film formed on a workpiece was brought into contact with an electroless gold plating solution of the following formulation under the following plating conditions to form an electroless gold plating film on the electroless nickel-phosphorus plating film.

[0275] Electroless gold plating formulation

[0276] As a basic composition, 1.8 g / L of potassium gold cyanide and 15 g / L of sodium ethylenediaminetetraacetate were mixed, and after adding other trace additives, the pH was adjusted to 5.0 using sulfuric acid and ammonia water.

[0277] Conditions for electroless gold plating

[0278] Liquid temperature: 85℃

[0279] Contact time with plating solution: 10 minutes

[0280] Based on the above, a plating film for metal sintering bonding was manufactured in which the following electroless nickel-phosphorus plating film and electroless gold plating film were formed in this order on a workpiece.

[0281] · Electroless nickel-phosphorus plating: Phosphorus content 4 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0282] · Electroless gold plating film: Thickness 0.05 µm

[0283] (Example 7) Workpiece: Electroless nickel-phosphorus plating Film: Electroless gold plating Film

[0284] By changing the composition and plating conditions of the electroless nickel-phosphorus plating of Example 6 as follows, a plating film for metal sintering bonding was prepared in which the following electroless nickel-phosphorus plating film and electroless gold plating film were formed in this order on the workpiece.

[0285] Formulation of electroless nickel-phosphorus plating

[0286] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 10 g / L of sodium hypophosphite, 20 g / L of glycine, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0287] Conditions for electroless nickel-phosphorus plating

[0288] Liquid temperature: 90℃

[0289] Contact time with plating solution: 25 minutes

[0290] · Electroless nickel-phosphorus plating: Phosphorus content 2 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0291] · Electroless gold plating film: Thickness 0.05 µm

[0292] (Example 8) Workpiece: Electroless nickel-phosphorus plating film: Electroless palladium plating film - Electroless silver plating film

[0293] Formation of an electroless nickel-phosphorus plating film

[0294] The workpiece was brought into contact with an electroless nickel-phosphorus plating solution of the following formulation under the following conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0295] Formulation of electroless nickel-phosphorus plating

[0296] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 10 g / L of sodium hypophosphite, 20 g / L of glycine, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0297] Conditions for electroless nickel-phosphorus plating

[0298] Liquid temperature: 90℃

[0299] Contact time with plating solution: 25 minutes

[0300] Formation of an electroless palladium plating film

[0301] An electroless nickel-phosphorus plating film formed on a workpiece was brought into contact with an electroless palladium plating solution of the following formulation under the following conditions to form an electroless palladium plating film on the electroless nickel-phosphorus plating film.

[0302] Formulation of electroless palladium plating

[0303] As a basic composition, 1.5 g / L of palladium chloride, 10 g / L of sodium formate, and 15 g / L of ethylenediamine were mixed, and after adding other trace additives, the pH was adjusted to 6.0 using hydrochloric acid and ammonia water.

[0304] Conditions for electroless palladium plating

[0305] Liquid temperature: 55℃

[0306] Contact time with plating solution: 10 minutes

[0307] Formation of an electroless silver plating film

[0308] The electroless palladium plating film formed as described above was brought into contact with an electroless silver plating solution of the following formulation under the following conditions to form an electroless silver plating film on the electroless palladium plating film.

[0309] Formulation of electroless silver plating

[0310] As a basic composition, 1.7 g / L silver nitrate, 1.5 g / L water-soluble hydrazine derivative, 20 g / L 1-methylhydantoin, and 0.5 mg / L lead acetate were combined, and after adding other trace additives, the pH was adjusted to 10 using nitric acid and sodium hydroxide.

[0311] Conditions for electroless silver plating

[0312] Liquid temperature: 70℃

[0313] Contact time with plating solution: 20 minutes

[0314] According to the above, a plating film for metal sintering bonding was manufactured in which the following electroless nickel-phosphorus plating film, electroless palladium plating film, and electroless silver plating film were formed in this order on a workpiece.

[0315] · Electroless nickel-phosphorus plating: Phosphorus content 2 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0316] · Electroless palladium plating film: Thickness 0.1 µm

[0317] · Electroless silver plating: Thickness 0.2 µm

[0318] (Example 9) Workpiece: Electroless nickel-phosphorus plating film: Electroless palladium plating film: Electroless gold plating film

[0319] Formation of an electroless nickel-phosphorus plating film

[0320] The workpiece was brought into contact with an electroless nickel-phosphorus plating solution of the following formulation under the following conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0321] Formulation of electroless nickel-phosphorus plating

[0322] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 10 g / L of sodium hypophosphite, 20 g / L of glycine, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0323] Conditions for electroless nickel-phosphorus plating

[0324] Liquid temperature: 90℃

[0325] Contact time with plating solution: 25 minutes

[0326] Formation of an electroless palladium plating film

[0327] An electroless nickel-phosphorus plating film formed on a workpiece was brought into contact with an electroless palladium plating solution of the following formulation under the following conditions to form an electroless palladium plating film on the electroless nickel-phosphorus plating film.

[0328] Formulation of electroless palladium plating

[0329] As a basic composition, 1.5 g / L of palladium chloride, 10 g / L of sodium formate, and 15 g / L of ethylenediamine were mixed, and after adding other trace additives, the pH was adjusted to 6.0 using hydrochloric acid and ammonia water.

[0330] Conditions for electroless palladium plating

[0331] Liquid temperature: 55℃

[0332] Contact time with plating solution: 10 minutes

[0333] Formation of an electroless gold plating film

[0334] The electroless palladium plating film formed as described above was brought into contact with an electroless gold plating solution of the following formulation under the following conditions to form an electroless gold plating film on the electroless palladium plating film.

[0335] Electroless gold plating formulation

[0336] As a basic composition, 1.8 g / L of potassium gold cyanide and 15 g / L of sodium ethylenediaminetetraacetate were mixed, and after adding other trace additives, the pH was adjusted to 5.0 using sulfuric acid and ammonia water.

[0337] Conditions for electroless gold plating

[0338] Liquid temperature: 90℃

[0339] Contact time with plating solution: 10 minutes

[0340] Based on the above, a plating film for metal sintering bonding was manufactured in which the following electroless nickel-phosphorus plating film, electroless palladium plating film, and electroless gold plating film were formed in this order on a workpiece.

[0341] · Electroless nickel-phosphorus plating: Phosphorus content 2 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0342] · Electroless palladium plating film: Thickness 0.1 µm

[0343] · Electroless gold plating film: Thickness 0.05 µm

[0344] (Example 10) Workpiece: Electroless nickel-phosphorus plating film: Electroless palladium-phosphorus plating film: Electroless silver plating film

[0345] Formation of an electroless nickel-phosphorus plating film

[0346] The workpiece was brought into contact with an electroless Ni-P plating solution of the following formulation under the following conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0347] Formulation of electroless nickel-phosphorus plating

[0348] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 10 g / L of sodium hypophosphite, 20 g / L of glycine, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0349] Conditions for electroless nickel-phosphorus plating

[0350] Liquid temperature: 90℃

[0351] Contact time with plating solution: 25 minutes

[0352] Formation of electroless palladium-phosphorus plating film

[0353] An electroless nickel-phosphorus plating film formed on a workpiece was brought into contact with an electroless palladium-phosphorus plating solution of the following formulation under the following conditions to form an electroless palladium-phosphorus plating film on the electroless nickel-phosphorus plating film.

[0354] Formulation of electroless palladium-phosphorus plating

[0355] As a basic composition, 1.5 g / L of palladium chloride, 10 g / L of sodium hypophosphite, and 15 g / L of ethylenediamine were mixed, and after adding other trace additives, the pH was adjusted to 6.0 using hydrochloric acid and ammonia water.

[0356] Conditions for electroless palladium-phosphorus plating

[0357] Liquid temperature: 60℃

[0358] Contact time with plating solution: 10 minutes

[0359] Formation of an electroless silver plating film

[0360] The electroless palladium-phosphorus plating film formed as described above was brought into contact with an electroless silver plating solution of the following formulation under the following conditions to form an electroless silver plating film on the electroless palladium-phosphorus plating film.

[0361] Formulation of electroless silver plating

[0362] As a basic composition, 1.7 g / L silver nitrate, 1.5 g / L water-soluble hydrazine derivative, 20 g / L 1-methylhydantoin, and 0.5 mg / L lead acetate were combined, and after adding other trace additives, the pH was adjusted to 10 using nitric acid and sodium hydroxide.

[0363] Conditions for electroless silver plating

[0364] Liquid temperature: 70℃

[0365] Contact time with plating solution: 20 minutes

[0366] According to the above, a plating film for metal sintering bonding was prepared in which the following electroless nickel-phosphorus plating film, electroless palladium-phosphorus plating film, and electroless silver plating film were formed in this order on a workpiece.

[0367] · Electroless nickel-phosphorus plating: Phosphorus content 2 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0368] · Electroless palladium-phosphorus plating: Phosphorus content 1 mass%, thickness 0.1 µm

[0369] · Electroless silver plating: Thickness 0.2 µm

[0370] (Example 11) Workpiece: Electroless nickel-phosphorus plating film: Electroless palladium-phosphorus plating film: Electroless gold plating film

[0371] Formation of an electroless nickel-phosphorus plating film

[0372] The workpiece was brought into contact with an electroless Ni-P plating solution of the following formulation under the following conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0373] Formulation of electroless nickel-phosphorus plating

[0374] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 10 g / L of sodium hypophosphite, 20 g / L of glycine, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0375] Conditions for electroless nickel-phosphorus plating

[0376] Liquid temperature: 90℃

[0377] Contact time with plating solution: 25 minutes

[0378] Formation of electroless palladium-phosphorus plating film

[0379] An electroless nickel-phosphorus plating film formed on a workpiece was brought into contact with an electroless palladium-phosphorus plating solution of the following formulation under the following conditions to form an electroless palladium-phosphorus plating film on the electroless nickel-phosphorus plating film.

[0380] Formulation of electroless palladium-phosphorus plating

[0381] As a basic composition, 1.5 g / L of palladium chloride, 10 g / L of sodium hypophosphite, and 15 g / L of ethylenediamine were mixed, and after adding other trace additives, the pH was adjusted to 6.0 using hydrochloric acid and ammonia water.

[0382] Conditions for electroless palladium-phosphorus plating

[0383] Liquid temperature: 60℃

[0384] Contact time with plating solution: 10 minutes

[0385] Formation of an electroless gold plating film

[0386] The electroless palladium-phosphorus plating film formed as described above was brought into contact with an electroless gold plating solution of the following formulation under the following conditions to form an electroless gold plating film on the electroless palladium-phosphorus plating film.

[0387] Electroless gold plating formulation

[0388] As a basic composition, 1.8 g / L of potassium gold cyanide and 15 g / L of sodium ethylenediaminetetraacetate were mixed, and after adding other trace additives, the pH was adjusted to 5.0 using sulfuric acid and ammonia water.

[0389] Conditions for electroless gold plating

[0390] Liquid temperature: 90℃

[0391] Contact time with plating solution: 10 minutes

[0392] Based on the above, a plating film for metal sintering bonding was prepared in which the following electroless nickel-phosphorus plating film, electroless palladium-phosphorus plating film, and electroless gold plating film were formed in this order on a workpiece.

[0393] · Electroless nickel-phosphorus plating: Phosphorus content 2 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0394] · Electroless palladium-phosphorus plating: Phosphorus content 1 mass%, thickness 0.1 µm

[0395] · Electroless gold plating film: Thickness 0.05 µm

[0396] (Example 12) Workpiece: Electroless nickel-phosphorus plating film

[0397] Formation of an electroless nickel-phosphorus plating film

[0398] The workpiece was brought into contact with an electroless nickel-phosphorus plating solution of the following formulation under the following conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0399] Formulation of electroless nickel-phosphorus plating

[0400] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 20 g / L of sodium hypophosphite, 20 g / L of glycine, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0401] Conditions for electroless nickel-phosphorus plating

[0402] Liquid temperature: 90℃

[0403] Contact time with plating solution: 20 minutes

[0404] Based on the above, a plating film for metal sintering bonding was manufactured, wherein the following electroless nickel-phosphorus plating film was formed on a workpiece.

[0405] · Electroless nickel-phosphorus plating: Phosphorus content 4 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0406] (Example 13) Workpiece: Electroless nickel-phosphorus plating film

[0407] Formation of an electroless nickel-phosphorus plating film

[0408] The workpiece was brought into contact with an electroless nickel-phosphorus plating solution of the following formulation under the following conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0409] Formulation of electroless nickel-phosphorus plating

[0410] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 10 g / L of sodium hypophosphite, 20 g / L of glycine, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0411] Conditions for electroless nickel-phosphorus plating

[0412] Liquid temperature: 90℃

[0413] Contact time with plating solution: 25 minutes

[0414] Based on the above, a plating film for metal sintering bonding was manufactured, wherein the following electroless nickel-phosphorus plating film was formed on a workpiece.

[0415] · Electroless nickel-phosphorus plating: Phosphorus content 2 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0416] (Example 14) Workpiece: Electroless nickel-phosphorus plating film

[0417] Formation of an electroless nickel-phosphorus plating film

[0418] The workpiece was brought into contact with an electroless nickel-phosphorus plating solution of the following formulation under the following conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0419] Formulation of electroless nickel-phosphorus plating

[0420] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 8 g / L of sodium hypophosphite, 20 g / L of glycine, and 0.5 mg / L of lead acetate were mixed, and after adding other trace additives, the pH was adjusted to 6.5 using sulfuric acid and ammonia water.

[0421] Conditions for electroless nickel-phosphorus plating

[0422] Liquid temperature: 90℃

[0423] Contact time with plating solution: 25 minutes

[0424] Based on the above, a plating film for metal sintering bonding was manufactured, wherein the following electroless nickel-phosphorus plating film was formed on a workpiece.

[0425] · Electroless nickel-phosphorus plating: Phosphorus content 2 mass%, sulfur content 0.0001 mass%, thickness 4 µm

[0426] (Comparative Example 1) Workpiece: Electroless nickel-phosphorus plating film: Electroless silver plating film

[0427] Formation of an electroless nickel-phosphorus plating film

[0428] The workpiece was brought into contact with an electroless nickel-phosphorus plating solution of the following formulation under the following plating conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0429] Formulation of electroless nickel-phosphorus plating

[0430] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 25 g / L of sodium hypophosphite, 15 g / L of malic acid, and 0.5 mg / L of lead acetate were mixed, and after adding other trace additives, the pH was adjusted to 4.5 using sulfuric acid and ammonia water.

[0431] Conditions for electroless nickel-phosphorus plating

[0432] Liquid temperature: 90℃

[0433] Contact time with plating solution: 20 minutes

[0434] Formation of an electroless silver plating film

[0435] An electroless nickel-phosphorus plating film formed on a workpiece was brought into contact with an electroless silver plating solution of the following formulation under the following plating conditions to form an electroless silver plating film on the electroless nickel-phosphorus plating film.

[0436] Formulation of electroless silver plating

[0437] As a basic composition, 1.7 g / L silver nitrate, 1.5 g / L water-soluble hydrazine derivative, 20 g / L 1-methylhydantoin, and 0.5 mg / L lead acetate were combined, and after adding other trace additives, the pH was adjusted to 10 using nitric acid and sodium hydroxide.

[0438] Conditions for electroless silver plating

[0439] Liquid temperature: 60℃

[0440] Contact time with plating solution: 20 minutes

[0441] According to the above, a plating film for metal sintering bonding was manufactured in which the following electroless nickel-phosphorus plating film and electroless silver plating film were formed in this order on a workpiece.

[0442] · Electroless nickel-phosphorus plating: Phosphorus content 10 mass%, sulfur content 0.0001 mass%, thickness 4 µm

[0443] · Electroless silver plating: Thickness 0.2 µm

[0444] (Comparative Example 2) Workpiece: Electroless nickel-phosphorus plating Film: Electroless silver plating Film

[0445] By changing the composition and plating conditions of the electroless nickel-phosphorus plating of Comparative Example 1 as follows, a plating film for metal sintering bonding was produced in which the following electroless nickel-phosphorus plating film and electroless silver plating film were formed in this order on the workpiece.

[0446] Formulation of electroless nickel-phosphorus plating

[0447] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 25 g / L of sodium hypophosphite, 15 g / L of malic acid, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 4.8 using sulfuric acid and ammonia water.

[0448] Conditions for electroless nickel-phosphorus plating

[0449] Liquid temperature: 85℃

[0450] Contact time with plating solution: 20 minutes

[0451] · Electroless nickel-phosphorus plating: Phosphorus content 7 mass%, sulfur content 0.0001 mass%, thickness 4 µm

[0452] · Electroless silver plating: Thickness 0.2 µm

[0453] (Comparative Example 3) Workpiece: Electroless nickel-phosphorus plating Film: Electroless silver plating Film

[0454] By changing the composition and plating conditions of the electroless nickel-phosphorus plating of Comparative Example 1 as follows, a plating film for metal sintering bonding was produced in which the following electroless nickel-phosphorus plating film and electroless silver plating film were formed in this order on the workpiece.

[0455] Formulation of electroless nickel-phosphorus plating

[0456] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 25 g / L of sodium hypophosphite, 15 g / L of malic acid, 0.5 mg / L of lead acetate, and 0.2 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 4.5 using sulfuric acid and ammonia water.

[0457] Conditions for electroless nickel-phosphorus plating

[0458] Liquid temperature: 85℃

[0459] Contact time with plating solution: 20 minutes

[0460] · Electroless nickel-phosphorus plating: Phosphorus content 7 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0461] · Electroless silver plating: Thickness 0.2 µm

[0462] (Comparative Example 4) Workpiece: Electroless silver plating film

[0463] Formation of an electroless silver plating film

[0464] The workpiece to be plated was brought into contact with an electroless silver plating solution of the following formulation under the following plating conditions, and an electroless silver plating film was formed on the workpiece.

[0465] Formulation of electroless silver plating

[0466] As a basic composition, 1.7 g / L silver nitrate, 1.5 g / L water-soluble hydrazine derivative, 20 g / L 1-methylhydantoin, and 0.5 mg / L lead acetate were combined, and after adding other trace additives, the pH was adjusted to 10 using nitric acid and sodium hydroxide.

[0467] Conditions for electroless silver plating

[0468] Liquid temperature: 60℃

[0469] Contact time with plating solution: 20 minutes

[0470] By the above, a plating film for metal sintering bonding was manufactured, in which the following electroless silver plating film was formed on a workpiece.

[0471] · Electroless silver plating: Thickness 0.2 µm

[0472] (Comparative Example 5) Workpiece: Electroless silver plating film

[0473] Formation of an electroless silver plating film

[0474] The workpiece to be plated was brought into contact with an electroless silver plating solution of the following formulation under the following plating conditions, and an electroless silver plating film was formed on the workpiece.

[0475] Formulation of electroless silver plating

[0476] As a basic composition, 1.7 g / L silver nitrate, 1.5 g / L water-soluble hydrazine derivative, 20 g / L 1-methylhydantoin, and 0.5 mg / L lead acetate were combined, and after adding other trace additives, the pH was adjusted to 10 using nitric acid and sodium hydroxide.

[0477] Conditions for electroless silver plating

[0478] Liquid temperature: 70℃

[0479] Contact time with plating solution: 40 minutes

[0480] By the above, a plating film for metal sintering bonding was manufactured, in which the following electroless silver plating film was formed on a workpiece.

[0481] · Electroless silver plating: Thickness 1.0 µm

[0482] (Comparative Example 6) Workpiece: Electroless nickel-phosphorus plating film

[0483] Formation of an electroless nickel-phosphorus plating film

[0484] The workpiece was brought into contact with an electroless nickel-phosphorus plating solution of the following formulation under the following conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0485] Formulation of electroless nickel-phosphorus plating

[0486] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 25 g / L of sodium hypophosphite, 15 g / L of malic acid, and 0.5 mg / L of lead acetate were mixed, and after adding other trace additives, the pH was adjusted to 4.5 using sulfuric acid and ammonia water.

[0487] Conditions for electroless nickel-phosphorus plating

[0488] Liquid temperature: 90℃

[0489] Contact time with plating solution: 20 minutes

[0490] Based on the above, a plating film for metal sintering bonding was manufactured, wherein the following electroless nickel-phosphorus plating film was formed on a workpiece.

[0491] · Electroless nickel-phosphorus plating: Phosphorus content 10 mass%, sulfur content 0.0001 mass%, thickness 4 µm

[0492] (Comparative Example 7) Workpiece: Electroless nickel-phosphorus plating film

[0493] Formation of an electroless nickel-phosphorus plating film

[0494] The workpiece was brought into contact with an electroless nickel-phosphorus plating solution of the following formulation under the following conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0495] Formulation of electroless nickel-phosphorus plating

[0496] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 25 g / L of sodium hypophosphite, 15 g / L of malic acid, 0.5 mg / L of lead acetate, and 0.1 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 4.8 using sulfuric acid and ammonia water.

[0497] Conditions for electroless nickel-phosphorus plating

[0498] Liquid temperature: 85℃

[0499] Contact time with plating solution: 20 minutes

[0500] Based on the above, a plating film for metal sintering bonding was manufactured, wherein the following electroless nickel-phosphorus plating film was formed on a workpiece.

[0501] · Electroless nickel-phosphorus plating: Phosphorus content 7 mass%, sulfur content 0.0001 mass%, thickness 4 µm

[0502] (Comparative Example 8) Workpiece: Electroless nickel-phosphorus plating film

[0503] Formation of an electroless nickel-phosphorus plating film

[0504] The workpiece was brought into contact with an electroless nickel-phosphorus plating solution of the following formulation under the following conditions to form an electroless nickel-phosphorus plating film on the workpiece.

[0505] Formulation of electroless nickel-phosphorus plating

[0506] As a basic composition, 22.5 g / L of nickel sulfate·6H2O, 25 g / L of sodium hypophosphite, 15 g / L of malic acid, 0.5 mg / L of lead acetate, and 0.2 mg / L of thiourea were mixed, and after adding other trace additives, the pH was adjusted to 4.5 using sulfuric acid and ammonia water.

[0507] Conditions for electroless nickel-phosphorus plating

[0508] Liquid temperature: 85℃

[0509] Contact time with plating solution: 20 minutes

[0510] Based on the above, a plating film for metal sintering bonding was manufactured, wherein the following electroless nickel-phosphorus plating film was formed on a workpiece.

[0511] · Electroless nickel-phosphorus plating: Phosphorus content 7 mass%, sulfur content 0.0003 mass%, thickness 4 µm

[0512] (Comparative Example 9) Plated material as is (copper bulk material)

[0513] (Evaluation Method)

[0514] The following evaluation was performed on the examples and comparative examples.

[0515] Preparation of samples for measuring the bonding strength of silver sintered joints

[0516] In each example and comparative example, a semiconductor device was mounted on a metal sintering bonding plating film prepared using a silver sintering material. Specifically, as the silver sintering material, a paste material was used that mixed micron-sized silver flakes (manufactured by Kinzoku Hakufun Kogyo Co., Ltd., Fukuda) and an ether solvent (manufactured by Daicel Co., Ltd.). As the semiconductor device, a SiC dummy chip (3 mm × 3 mm × 1 mm) having a titanium / silver sputtered film (0.1 μm / 1.0 μm) formed on it was used. By bonding the metal sintering bonding plating film formed on the substrate and the SiC dummy chip having the titanium / silver sputtered film formed on it using the silver sintering material, a sample for evaluating silver sintering bonding was prepared. In addition, the bonding conditions of Examples 1 to 11 and Comparative Examples 1 to 5 were set to no pressure, atmospheric, 250°C, and 30 minutes, and the bonding conditions of Examples 12 to 14 and Comparative Examples 6 to 9 were set to 1 MPa pressure, atmospheric, 250°C, and 30 minutes.

[0517] Bond strength measurement

[0518] For the aforementioned evaluation samples, a shear test was performed using a bond tester (Nordson DAGE 4000 Plus) to measure the bonding strength between the plating film for metal sintering bonding and the silver sintered material. The shear test was performed immediately after silver sintering bonding and after heat treatment at 300°C for 500 hours, and the initial bonding performance and bonding performance after heat treatment were evaluated according to the following evaluation criteria.

[0519] 30 MPa or more: Good bonding strength

[0520] Less than 30 MPa: Insufficient bonding strength

[0521] The results are shown in Table 1.

[0522]

[0523] From the results of Table 1, it was found that in Examples 1 to 14, the initial bonding performance and bonding performance after heat treatment were excellent, and since the bonding strength did not decrease drastically even with heat treatment, the plating film had excellent heat resistance and cold shock resistance and was suitable for metal sintering bonding.

[0524] In this regard, in Comparative Examples 1 to 9, the bonding performance after heat treatment was significantly lower than the initial bonding performance, and it was found that the heat resistance and cold shock resistance were inferior compared to Examples 1 to 14.

Claims

Claim 1 (A) A plating film for metal sintering bonding having an electroless nickel-phosphorus plating film, wherein the phosphorus content of the (A) electroless nickel-phosphorus plating film is 4 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film, and further having (B) an electroless silver plating film on the (A) electroless nickel-phosphorus plating film. Claim 2 A plating film for metal sintering bonding according to claim 1, wherein the sulfur content of the electroless nickel-phosphorus plating film (A) is less than 0.0005 mass% with respect to 100 mass% of the electroless nickel-phosphorus plating film. Claim 3 A plating film for metal sintering bonding according to claim 1, wherein the sulfur content of the electroless nickel-phosphorus plating film (A) is 0.0001 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film. Claim 4 A plating film for metal sintering bonding according to claim 1, wherein the thickness of the (A) electroless nickel-phosphorus plating film is 0.1 to 20 μm. Claim 5 A plating film for metal sintering bonding according to claim 1, wherein the thickness of the (B) electroless silver plating film is 0.02 to 2 μm. Claim 6 A plating film for metal sintering bonding according to claim 1, further comprising (C) a barrier metal layer between (A) the electroless nickel-phosphorus plating film and (B) the electroless silver plating film. Claim 7 In claim 6, the above (C) barrier metal layer is an electroless palladium plating film or an electroless palladium-phosphorus plating film, a plating film for metal sintering bonding. Claim 8 A plating film for metal sintering bonding, wherein, in claim 1, it is for a metal sintering material containing silver and / or copper. Claim 9 A method for manufacturing a plating film for metal sintering bonding, wherein the plating film for metal sintering bonding is formed on a substrate, the method comprises: (1) a process 1 in which an electroless nickel-phosphorus plating solution is brought into contact with the surface of a substrate to form (A) an electroless nickel-phosphorus plating film on the substrate; (2) a process 2 in which an electroless silver plating solution is brought into contact with the surface of the electroless nickel-phosphorus plating film to form (B) an electroless silver plating film on the (A) electroless nickel-phosphorus plating film; and wherein the phosphorus content of the (A) electroless nickel-phosphorus plating film is 4 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film. Claim 10 A semiconductor mounting substrate characterized by having a metal sintering bonding plating film having (A) an electroless nickel-phosphorus plating film and (B) an electroless silver plating film on the (A) electroless nickel-phosphorus plating film, wherein the metal sintering bonding plating film is laminated thereon, and a semiconductor device having a metal sintering layer interposed on the metal sintering bonding plating film, wherein the phosphorus content of the (A) electroless nickel-phosphorus plating film is 4 mass% or less with respect to 100 mass% of the electroless nickel-phosphorus plating film. Claim 11 delete Claim 12 delete

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