A bonding structure formed on a substrate includes an indium layer and a passivating nickel plating formed on the indium layer. The nickel plating serves to prevent a reaction involving the indium layer.

A surface-treated copper foil including a treating surface, where the root mean square height (Sq) of the treating surface is in a range of 0.20 to 1.50 μm and the texture aspect ratio (Str) of the treating surface is not greater than 0.65. When the surface-treated copper foil is heated at a temperature of 200° C. for 1 hour, the ratio of the integrated intensity of (111) peak to the sum of the integrated intensities of (111) peak, (200) peak, and (220) peak of the treating surface is at least 60%.

A Ni-plated steel sheet includes a base steel sheet and a Ni-based coating layer that is disposed on a surface of the base steel sheet. The Ni-based coating layer includes a Fe—Ni alloy region that is formed on the surface of the base steel sheet. The Fe—Ni alloy region includes a mixed phase composed of a bcc phase and an fcc phase, and a component of the Fe—Ni alloy region includes 5 mass % or more of Fe and a remainder including 90 mass % or more of Ni.

A Ni-plated steel sheet includes a base steel sheet and a Ni-based coating layer that is disposed on a surface of the base steel sheet. The Ni-based coating layer includes a Fe—Ni alloy region that is formed on the surface of the base steel sheet. The Fe—Ni alloy region includes a mixed phase composed of a bcc phase and an fcc phase, and a component of the Fe—Ni alloy region includes 5 mass % or more of Fe and a remainder including 90 mass % or more of Ni.

A Ni-plated steel sheet includes a base steel sheet and a Ni-based coating layer that is disposed on a surface of the base steel sheet. The distribution of carbon concentration in a depth direction obtained by performing GDS analysis on the Ni-plated steel sheet has a peak indicating the carbon concentration that is equal to or more than twice the carbon concentration of a thickness middle portion of the base steel sheet in the vicinity of an interface between the base steel sheet and the Ni-based coating layer.

A Ni-plated steel sheet includes a base steel sheet and a Ni-based coating layer that is disposed on a surface of the base steel sheet. The distribution of carbon concentration in a depth direction obtained by performing GDS analysis on the Ni-plated steel sheet has a peak indicating the carbon concentration that is equal to or more than twice the carbon concentration of a thickness middle portion of the base steel sheet in the vicinity of an interface between the base steel sheet and the Ni-based coating layer.

Techniques including methods and apparatuses for selective measurement and monitoring of halide concentrations in processing solutions for iron triad metals and their alloys are provided. Methods include monitoring of a halide ion, for example, based on a first analytical method such as conductivity with a compensation of the results for a main metal concentration such as a second analytical measurement of concentration of an iron triad metal (e.g., nickel (Ni)). From such measurements, a concentration of certain halide ions can be selectively determined.

Provided is a method for forming a metal film using a solid-state electrolyte membrane, and the method allows a metal film having a smooth surface to be formed and an additive to sufficiently serve its function. A method for forming a metal film includes the successive steps of (a) supplying a solution to a solution-housing space, the solution containing ions of the metal and an additive; (b) increasing a pressure of the solution in the solution-housing space in a state where the solution-housing space is uncommunicated with a solution tank and the substrate held by a holder is in contact with the solid-state electrolyte membrane; (c) decreasing the pressure of the solution in the solution-housing space; and (d) forming the film of the metal on the substrate by applying a voltage between an anode and the substrate while the solution is circulated between the solution-housing space and the solution tank.

In a terminal material with a silver coating film including a silver layer on a surface, a terminal and a terminal material having high reliability are easily manufactured with low cost without a heat treatment. A base material formed of copper or a copper alloy; and nickel layer, an intermediate layer, and a silver layer laminated on the base material in this order are included, the nickel layer has a thickness of 0.05 μm to 5.00 μm and is formed of nickel or a nickel alloy, the intermediate layer has a thickness of 0.02 μm to 1.00 μm and is an alloy layer containing silver (Ag) and a substance X, and the substance X includes one or more kinds of tin, bismuth, gallium, indium, and germanium.

In a terminal material with a silver coating film including a silver layer on a surface, a terminal and a terminal material having high reliability are easily manufactured with low cost without a heat treatment. A base material formed of copper or a copper alloy; and nickel layer, an intermediate layer, and a silver layer laminated on the base material in this order are included, the nickel layer has a thickness of 0.05 μm to 5.00 μm and is formed of nickel or a nickel alloy, the intermediate layer has a thickness of 0.02 μm to 1.00 μm and is an alloy layer containing silver (Ag) and a substance X, and the substance X includes one or more kinds of tin, bismuth, gallium, indium, and germanium.