It is an object to provide a Cu alloy bonding wire for a semiconductor device that can satisfy required performance in high-density LSI applications. In the Cu alloy bonding wire for a semiconductor device according to the present invention, each of abundance ratios of crystal orientations <100>, <110> and <111> having an angular difference of 15 degrees or less from a direction perpendicular to one plane including a wire center axis out of crystal orientations on a wire surface is 3% or more and less than 27% in average area percentage.

It is an object to provide a Cu alloy bonding wire for a semiconductor device that can satisfy required performance in high-density LSI applications. In the Cu alloy bonding wire for a semiconductor device according to the present invention, each of abundance ratios of crystal orientations <100>, <110> and <111> having an angular difference of 15 degrees or less from a direction perpendicular to one plane including a wire center axis out of crystal orientations on a wire surface is 3% or more and less than 27% in average area percentage.

A method for manufacturing a bonding wire includes: putting a surface layer metal of a bonding wire in a crucible having a die cooler provided at the lower part thereof and melting the same; putting a main component metal core of the bonding wire in a core guide located at the upper part of the die cooler of the crucible and heating the core guide to the melting point or below of the metal core; transferring the metal core toward the die cooler so as to allow the molten surface layer metal to be injected to the surface of the metal core; and manufacturing a 50 m to 350 m bonding wire from the cast wire precursor by using a drawing die.

A method for manufacturing a bonding wire includes: putting a surface layer metal of a bonding wire in a crucible having a die cooler provided at the lower part thereof and melting the same; putting a main component metal core of the bonding wire in a core guide located at the upper part of the die cooler of the crucible and heating the core guide to the melting point or below of the metal core; transferring the metal core toward the die cooler so as to allow the molten surface layer metal to be injected to the surface of the metal core; and manufacturing a 50 m to 350 m bonding wire from the cast wire precursor by using a drawing die.

The present invention provides a bonding wire capable of simultaneously satisfying ball bonding reliability and wedge bondability required of bonding wires for memories, the bonding wire including a core material containing one or more of Ga, In, and Sn for a total of 0.1 to 3.0 at % with a balance being made up of Ag and incidental impurities; and a coating layer formed over a surface of the core material, containing one or more of Pd and Pt, or Ag and one or more of Pd and Pt, with a balance being made up of incidental impurities, wherein the coating layer is 0.005 to 0.070 m in thickness.

The present invention provides a bonding wire capable of simultaneously satisfying ball bonding reliability and wedge bondability required of bonding wires for memories, the bonding wire including a core material containing one or more of Ga, In, and Sn for a total of 0.1 to 3.0 at % with a balance being made up of Ag and incidental impurities; and a coating layer formed over a surface of the core material, containing one or more of Pd and Pt, or Ag and one or more of Pd and Pt, with a balance being made up of incidental impurities, wherein the coating layer is 0.005 to 0.070 m in thickness.

An assembly that includes a first substrate, a second substrate, and a stress mitigation layer disposed between the first and the second substrates. The stress mitigation layer is directly bonded onto the second substrate, and the second substrate is separated from the intermetallic compound layer by the stress mitigation layer. The stress mitigation layer has a high purity of at least 99% aluminum such that the stress mitigation layer reduces thermomechanical stresses on the first and second substrates. The assembly further includes an intermetallic compound layer disposed between the first substrate and the stress mitigation layer such that the stress mitigation layer is separated from the first substrate by the intermetallic compound layer.

An assembly that includes a first substrate, a second substrate, and a stress mitigation layer disposed between the first and the second substrates. The stress mitigation layer is directly bonded onto the second substrate, and the second substrate is separated from the intermetallic compound layer by the stress mitigation layer. The stress mitigation layer has a high purity of at least 99% aluminum such that the stress mitigation layer reduces thermomechanical stresses on the first and second substrates. The assembly further includes an intermetallic compound layer disposed between the first substrate and the stress mitigation layer such that the stress mitigation layer is separated from the first substrate by the intermetallic compound layer.

In a copper alloy bonding wire for semiconductor devices, the bonding longevity of a ball bonded part under high-temperature and high-humidity environments is improved. The copper alloy bonding wire for semiconductor devices includes in total 0.03% by mass or more to 3% by mass or less of at least one or more kinds of elements selected from Ni, Zn, Ga, Ge, Rh, In, Ir, and Pt (first element), with the balance Cu and inevitable impurities. The inclusion of a predetermined amount of the first element suppresses production of an intermetallic compound susceptible to corrosion under high-temperature and high-humidity environments at the wire bonding interface and improves the bonding longevity of a ball bonded part.

In a copper alloy bonding wire for semiconductor devices, the bonding longevity of a ball bonded part under high-temperature and high-humidity environments is improved. The copper alloy bonding wire for semiconductor devices includes in total 0.03% by mass or more to 3% by mass or less of at least one or more kinds of elements selected from Ni, Zn, Ga, Ge, Rh, In, Ir, and Pt (first element), with the balance Cu and inevitable impurities. The inclusion of a predetermined amount of the first element suppresses production of an intermetallic compound susceptible to corrosion under high-temperature and high-humidity environments at the wire bonding interface and improves the bonding longevity of a ball bonded part.