There is provided a bonding wire for a semiconductor device including a coating layer having Pd as a main component on a surface of a Cu alloy core material and a skin alloy layer containing Au and Pd on a surface of the coating layer, the bonding wire further improving 2nd bondability on a Pd-plated lead frame and achieving excellent ball bondability even in a high-humidity heating condition. The bonding wire for a semiconductor device including the coating layer having Pd as a main component on the surface of the Cu alloy core material and the skin alloy layer containing Au and Pd on the surface of the coating layer has a Cu concentration of 1 to 10 at % at an outermost surface thereof and has the core material containing either or both of Pd and Pt in a total amount of 0.1 to 3.0% by mass, thereby achieving improvement in the 2nd bondability and excellent ball bondability in the high-humidity heating condition. Furthermore, a maximum concentration of Au in the skin alloy layer is preferably 15 at % to 75 at %.

A micro-coaxial wire has an overall diameter in a range of 0.1 m-550 m, a conductive core of the wire has a cross-sectional diameter in a range of 0.05 m-304 m, an insulator is disposed on the conductive core with thickness in a range of 0.005 m-180 m, and a conductive shield layer is disposed on the insulator with thickness in a range of 0.009 m-99 m.

A micro-coaxial wire has an overall diameter in a range of 0.1 m-550 m, a conductive core of the wire has a cross-sectional diameter in a range of 0.05 m-304 m, an insulator is disposed on the conductive core with thickness in a range of 0.005 m-180 m, and a conductive shield layer is disposed on the insulator with thickness in a range of 0.009 m-99 m.

There is provided a bonding wire for a semiconductor device including a coating layer having Pd as a main component on a surface of a Cu alloy core material and a skin alloy layer containing Au and Pd on a surface of the coating layer, the bonding wire further improving 2nd bondability on a Pd-plated lead frame and achieving excellent ball bondability even in a high-humidity heating condition. The bonding wire for a semiconductor device including the coating layer having Pd as a main component on the surface of the Cu alloy core material and the skin alloy layer containing Au and Pd on the surface of the coating layer has a Cu concentration of 1 to 10 at % at an outermost surface thereof and has the core material containing either or both of Pd and Pt in a total amount of 0.1 to 3.0% by mass, thereby achieving improvement in the 2nd bondability and excellent ball bondability in the high-humidity heating condition. Furthermore, a maximum concentration of Au in the skin alloy layer is preferably 15 at % to 75 at %.

A method for attaching a prefabricated miniature coaxial wire to a first electrical connection point, the prefabricated miniature coaxial wire having an electrically conductive core disposed within an electrical insulation layer disposed within an electrically conductive shield layer, includes attaching an exposed portion of the electrically conductive core at a distal end of the prefabricated miniature coaxial wire to the first electrical connection point, thereby establishing electrical conductivity between the electrically conductive core and the first electrical connection point, depositing a layer of electrically insulating material onto the exposed portion of the electrically conductive core such that the exposed portion of the electrically conductive core and the first electrical connection point is encased in the layer of electrically insulating material, and connecting the electrically conductive shield layer to a second electrical connection point using a connector formed from an electrically conductive material.

A method for attaching a prefabricated miniature coaxial wire to a first electrical connection point, the prefabricated miniature coaxial wire having an electrically conductive core disposed within an electrical insulation layer disposed within an electrically conductive shield layer, includes attaching an exposed portion of the electrically conductive core at a distal end of the prefabricated miniature coaxial wire to the first electrical connection point, thereby establishing electrical conductivity between the electrically conductive core and the first electrical connection point, depositing a layer of electrically insulating material onto the exposed portion of the electrically conductive core such that the exposed portion of the electrically conductive core and the first electrical connection point is encased in the layer of electrically insulating material, and connecting the electrically conductive shield layer to a second electrical connection point using a connector formed from an electrically conductive material.

A bonding wire for a semiconductor device including a coating layer having Pd as a main component on the surface of a Cu alloy core material and a skin alloy layer containing Au and Pd on the surface of the coating layer has a Cu concentration of 1 to 10 at % at an outermost surface thereof and has the core material containing a metallic element of Group 10 of the Periodic Table of Elements in a total amount of 0.1 to 3.0% by mass, thereby achieving improvement in 2nd bondability and excellent ball bondability in a high-humidity heating condition. Furthermore, a maximum concentration of Au in the skin alloy layer is preferably 15 at % to 75 at %.

There is provided a bonding wire for a semiconductor device including a coating layer having Pd as a main component on a surface of a Cu alloy core material and a skin alloy layer containing Au and Pd on a surface of the coating layer, the bonding wire further improving 2nd bondability on a Pd-plated lead frame and achieving excellent ball bondability even in a high-humidity heating condition. The bonding wire for a semiconductor device including the coating layer having Pd as a main component on the surface of the Cu alloy core material and the skin alloy layer containing Au and Pd on the surface of the coating layer has a Cu concentration of 1 to 10 at % at an outermost surface thereof and has the core material containing either or both of Pd and Pt in a total amount of 0.1 to 3.0% by mass, thereby achieving improvement in the 2nd bondability and excellent ball bondability in the high-humidity heating condition. Furthermore, a maximum concentration of Au in the skin alloy layer is preferably 15 at % to 75 at %.

A bonding wire for a semiconductor device including a coating layer having Pd as a main component on the surface of a Cu alloy core material and a skin alloy layer containing Au and Pd on the surface of the coating layer has a Cu concentration of 1 to 10 at % at an outermost surface thereof and has the core material containing a metallic element of Group 10 of the Periodic Table of Elements in a total amount of 0.1 to 3.0% by mass, thereby achieving improvement in 2nd bondability and excellent ball bondability in a high-humidity heating condition. Furthermore, a maximum concentration of Au in the skin alloy layer is preferably 15 at % to 75 at %.