Bonding wire for semiconductor devices

Abstract

There is provided a novel Cu bonding wire that achieves a favorable FAB shape and achieves a favorable bond reliability of the 2nd bonded part even in a rigorous high-temperature environment. The bonding wire for semiconductor devices is characterized in that the bonding wire includes: a core material of Cu or Cu alloy; and a coating layer containing conductive metal other than Cu formed on a surface of the core material, wherein the coating layer has a region containing Pd as a main component on a core material side, and has a region containing Ni and Pd in a range from a wire surface to a depth of 0.5d when a thickness of the coating layer is defined as d (nm) in a thickness direction of the coating layer, the thickness d of the coating layer is 10 nm or more and 130 nm or less, a ratio C/Cof a concentration C(mass %) of Ni to a concentration C(mass %) of Pd relative to the entire wire is 0.02 or more and 0.7 or less, a position indicating a maximum concentration of Ni is present in the range from the wire surface to a depth of 0.5d in a concentration profile in a depth direction of the wire, and the maximum concentration of Ni is 10 atomic % or more, and at least one of the following conditions (i) and (ii) is satisfied: