In accordance with one embodiment of the present disclosure, a method for depositing metal on a reactive metal film on a workpiece includes electrochemically depositing a metallization layer on a seed layer formed on a workpiece using a plating electrolyte having at least one plating metal ion, a pH range of about 1 to about 6, and applying a cathodic potential in the range of about −0.5 V to about −4 V. The workpiece includes a barrier layer disposed between the seed layer and a dielectric surface of the workpiece, the barrier layer including a first metal having a standard electrode potential more negative than 0 V and the seed layer including a second metal having a standard electrode potential more positive than 0 V.

The present disclosure involves a method for partial gold plating of a metal packaging housing and a packaging housing thereof. The packaging housing may include a base. The base may be provided with at least one lead hole. A housing lead may be interspersed in the lead hole. The lead hole may be also provided with an insulator surrounding the housing lead. The method may include operations such as nickel plating, oxidation, gold plating, reduction, etc.

The present disclosure involves a method for partial gold plating of a metal packaging housing and a packaging housing thereof. The packaging housing may include a base. The base may be provided with at least one lead hole. A housing lead may be interspersed in the lead hole. The lead hole may be also provided with an insulator surrounding the housing lead. The method may include operations such as nickel plating, oxidation, gold plating, reduction, etc.

A metal nanolaminate includes a plurality of units stacked in a longitudinal direction of the metal nanolaminate. Each of the units includes a first layer and a second layer stacked in the longitudinal direction. The first layer includes a first metal material formed of a first metallic element and the second layer includes the first metal material and a second metal material formed of a second metallic element. Each of the first layer and the second layer has a thickness of at least 5 nm but less than 100 nm in the longitudinal direction.

A metal nanolaminate includes a plurality of units stacked in a longitudinal direction of the metal nanolaminate. Each of the units includes a first layer and a second layer stacked in the longitudinal direction. The first layer includes a first metal material formed of a first metallic element and the second layer includes the first metal material and a second metal material formed of a second metallic element. Each of the first layer and the second layer has a thickness of at least 5 nm but less than 100 nm in the longitudinal direction.

The surface of a substrate made of stainless steel foil is coated with a Sn alloy layer, with a strike layer in between. The coating weight of the strike layer is 0.001 g/m.sup.2 to 1 g/m.sup.2.

The surface of a substrate made of stainless steel foil is coated with a Sn alloy layer, with a strike layer in between. The coating weight of the strike layer is 0.001 g/m.sup.2 to 1 g/m.sup.2.

To provide a surface treatment solution and treatment method for gold or gold alloy plating that effectively suppresses corrosion of underlying metal or substrate metal from pinholes that develop on the gold or gold alloy plating film. [Solution] A surface treatment solution containing a disulfide compound is brought into contact with a gold or gold alloy plating film. A compound represented by the following formula (2) is preferred as the disulfide compound.
X.sup.1O.sub.3S—R.sup.3—S—S—R.sup.4—SO.sub.3X.sup.2  (2)
in the formula, R.sup.3 and R.sup.4 independently represent a linear or branched alkylene group having from 1 to 10 carbon atoms, cyclic alkylene group having from 3 to 10 carbon atoms, or phenylene group, R.sup.3 and R.sup.4 independently may be substituted by one or more substituents selected from an alkyl group, halogen atom, hydroxyl group, or alkoxy group, and X.sup.1 and X.sup.2 represent monovalent cations.

To provide a surface treatment solution and treatment method for gold or gold alloy plating that effectively suppresses corrosion of underlying metal or substrate metal from pinholes that develop on the gold or gold alloy plating film. [Solution] A surface treatment solution containing a disulfide compound is brought into contact with a gold or gold alloy plating film. A compound represented by the following formula (2) is preferred as the disulfide compound.
X.sup.1O.sub.3S—R.sup.3—S—S—R.sup.4—SO.sub.3X.sup.2  (2)
in the formula, R.sup.3 and R.sup.4 independently represent a linear or branched alkylene group having from 1 to 10 carbon atoms, cyclic alkylene group having from 3 to 10 carbon atoms, or phenylene group, R.sup.3 and R.sup.4 independently may be substituted by one or more substituents selected from an alkyl group, halogen atom, hydroxyl group, or alkoxy group, and X.sup.1 and X.sup.2 represent monovalent cations.

The invention relates to a cyanide-free formulation for the electrodeposition of a layer of gold and silver on electrically conductive substrates, wherein the formulation respectively contains a complexing agent from the group of sulfites and thiosulfates and is characterized in that at least one transition metal from the 5th or 6th sub-group is added in the form of the soluble oxygen acid thereof in order to increase the bath stability.