Abstract: An electroless plating process that enables reduction in production costs and a two-layer plating film obtained by the process including an electroless plating process for forming a nickel plating film and a gold plating film in this order on a surface of a copper material by a electroless plating method. The electroless plating process includes a step of forming a nickel plating film containing boron by a reductive electroless nickel strike plating method, and a step of forming a gold plating film by a reductive electroless gold plating method. The two-layer plating film according to the present disclosure is formed by this process.

Abstract: An object of the present invention is to provide an electroless nickel plating solution that can form a nickel film which can surely cover a surface of a copper material even when the film thickness is thin, and a method for forming a nickel film using the electroless nickel plating solution. In order to solve the above-mentioned problems, the electroless nickel strike plating solution used for forming the nickel film on the surface of the copper material includes: a water-soluble nickel salt in a concentration of 0.002 to 1 g/L in terms of nickel; one or more carboxylic acids or salts thereof; and one or more reducing agents selected from the group of dimethylamine borane, trimethylamine borane, hydrazine and hydrazine derivatives.

Abstract: An object is to provide an electroless plating process which can thin a film thickness of a nickel film and can obtain a film having excellent mounting characteristics, when the nickel film and a gold film are sequentially formed on a surface of a copper material. In order to solve the above-mentioned problems, provided is an electroless plating process which sequentially forms a nickel film and a gold film on a surface of a copper material by an electroless plating method and includes: a step of forming the nickel film on the surface of the copper material by an electroless strike plating method; and a step of forming the gold film by a reduction-type electroless plating method.

Abstract: A controller according to the present disclosure includes a target current controller, a dither controlling unit, an output-duty generating unit, and a Pulse-Width-Modulation-pulse (PWM-pulse) converting unit. The dither controlling unit generates a dither duty for providing, to a target current duty of a load, a dither having predetermined dither period. The target current controller calculates, for each predetermined feedback period, an average value of a feedback current from the load and generates the target current duty based on the average value. The output-duty generating unit generates an output duty obtained by adding the dither duty generated by the dither controlling unit to the target current duty generated by the target current controller. The PWM-pulse converting unit converts the output duty generated by the output-duty generating unit to PWM pulses.

Abstract: Provided is an electroless platinum plating solution that can exhibit solution stability without the use of heavy metal ions or thiol compounds and can prevent the generation of ammonia gas. The electroless platinum plating solution is characterized by comprising a water-soluble platinum compound, and one or more reducing agents selected from the group consisting of formalin, glucose, formic acid and formates. The water-soluble platinum compound is preferably one or more water-soluble platinum compounds selected from the group consisting of platinous chloride (II), hydrogen tetrachloroplatinate (II), tetrachloroplatinate (II), platinic chloride (IV), hydrogen hexachloroplatinate (IV), hexachloroplatinate (IV), hydrogen hexahydroxoplatinate (IV), hexahydroxoplatinate (IV) and dichlorotetraammineplatinum (II). The electroless platinum plating solution preferably comprises an organic acid.

Abstract: A controller according to the present disclosure includes a target current controller, a dither controlling unit, an output-duty generating unit, and a Pulse-Width-Modulation-pulse (PWM-pulse) converting unit. The dither controlling unit generates a dither duty for providing, to a target current duty of a load, a dither having predetermined dither period. The target current controller calculates, for each predetermined feedback period, an average value of a feedback current from the load and generates the target current duty based on the average value. The output-duty generating unit generates an output duty obtained by adding the dither duty generated by the dither controlling unit to the target current duty generated by the target current controller. The PWM-pulse converting unit converts the output duty generated by the output-duty generating unit to PWM pulses.

Abstract: The present invention has an object to provide an electroless gold plating solution capable of suppressing the corrosion of a substrate metal and realizing excellent wire bondability, and containing no hazardous substance. In order to achieve the object, as a reductive electroless gold plating solution used for formation of an electroless plated gold film on a surface of a plating target by electroless plating, an electroless plating solution containing a water-soluble gold compound, citric acid or a citrate salt, ethylenediaminetetraacetic acid or an ethylenediaminetetraacetate salt, hexamethylenetetramine, and a chain polyamine having an alkyl group having 3 or more carbon atoms and 3 or more amino groups is adopted.