A core material including a core and a solder plating layer of a (SnBi)-based solder alloy made of Sn and Bi on a surface of the core. Bi in the solder plating layer is distributed in the solder plating layer at a concentration ratio in a predetermined range of, for example, 91.7% to 106.7%. Bi in the solder plating layer is homogeneous, and thus, a Bi concentration ratio is in a predetermined range over the entire solder plating layer including an inner circumference side and an outer circumference side in the solder plating layer.

A Cu core ball and a method of manufacturing such a Cu core ball. Purity of the Cu internal ball is at least 99.9% and not greater than 99.995%. A total contained amount of Pb and/or Bi in impurity contained in the Cu ball is equal to or larger than 1 ppm. Its sphericity is at least 0.95. A solder plating film coated on the Cu ball is of Sn solder or a lead free solder alloy whose primary component is Sn. In the solder plating film, a contained amount of U is not more than 5 ppb and that of Th is not more than 5 ppb. A total alpha dose of the Cu ball and the solder plating film is not more than 0./0200 cph/cm2. An arithmetic average roughness of the Cu core ball is equal to or less than 0.3 m.

A Cu core ball and a method of manufacturing such a Cu core ball. Purity of the Cu internal ball is at least 99.9% and not greater than 99.995%. A total contained amount of Pb and/or Bi in impurity contained in the Cu ball is equal to or larger than 1 ppm. Its sphericity is at least 0.95. A solder plating film coated on the Cu ball is of Sn solder or a lead free solder alloy whose primary component is Sn. In the solder plating film, a contained amount of U is not more than 5 ppb and that of Th is not more than 5 ppb. A total alpha dose of the Cu ball and the solder plating film is not more than 0./0200 cph/cm2. An arithmetic average roughness of the Cu core ball is equal to or less than 0.3 m.

The disclosure provides a SnIn electroplating bath that is Pb-free, environmentally safe, operates at room temperature, and does not require changes in existing plating assemblies. Room temperature aging and limited thermal cycling tests show that the electroplated SnIn alloy film on a Cu substrate effectively mitigates whisker growth.

The disclosure provides a SnIn electroplating bath that is Pb-free, environmentally safe, operates at room temperature, and does not require changes in existing plating assemblies. Room temperature aging and limited thermal cycling tests show that the electroplated SnIn alloy film on a Cu substrate effectively mitigates whisker growth.

A plating solution including a soluble salt containing at least a stannous salt; an acid selected from organic acid and inorganic acid or a salt thereof; and an additive containing sulfonium salt with one or more of aromatic rings is provided.

A plating solution including a soluble salt containing at least a stannous salt; an acid selected from organic acid and inorganic acid or a salt thereof; and an additive containing sulfonium salt with one or more of aromatic rings is provided.

A semiconductor apparatus includes a semiconductor device, on-semiconductor-device metal pad and metal interconnect each electrically connected to the semiconductor device, a through electrode and a solder bump each electrically connected to the metal interconnect, a first insulating layer on which the semiconductor device is placed, a second insulating layer formed on the semiconductor device, a third insulating layer formed on the second layer. The metal interconnect is electrically connected to the semiconductor device via the on-semiconductor-device metal pad at an upper surface of the second layer, penetrates the second layer from its upper surface, and is electrically connected to the through electrode at an lower surface of the second layer, and an under-semiconductor-device metal interconnect is between the first layer and the semiconductor device, and the under-semiconductor-device metal interconnect is electrically connected to the metal interconnect at the lower surface of the second layer.

A semiconductor apparatus includes a semiconductor device, on-semiconductor-device metal pad and metal interconnect each electrically connected to the semiconductor device, a through electrode and a solder bump each electrically connected to the metal interconnect, a first insulating layer on which the semiconductor device is placed, a second insulating layer formed on the semiconductor device, a third insulating layer formed on the second layer. The metal interconnect is electrically connected to the semiconductor device via the on-semiconductor-device metal pad at an upper surface of the second layer, penetrates the second layer from its upper surface, and is electrically connected to the through electrode at an lower surface of the second layer, and an under-semiconductor-device metal interconnect is between the first layer and the semiconductor device, and the under-semiconductor-device metal interconnect is electrically connected to the metal interconnect at the lower surface of the second layer.

An apparatus for continuous simultaneous electroplating of two metals having substantially different standard electrodeposition potentials (e.g., for deposition of SnAg alloys) comprises an anode chamber for containing an anolyte comprising ions of a first, less noble metal, (e.g., tin), but not of a second, more noble, metal (e.g., silver) and an active anode; a cathode chamber for containing catholyte including ions of a first metal (e.g., tin), ions of a second, more noble, metal (e.g., silver), and the substrate; a separation structure positioned between the anode chamber and the cathode chamber, where the separation structure substantially prevents transfer of more noble metal from catholyte to the anolyte; and fluidic features and an associated controller coupled to the apparatus and configured to perform continuous electroplating, while maintaining substantially constant concentrations of plating bath components for extended periods of use.