| abstract |
Provided is a Cu bonding wire having a Pd coating layer on the surface, which has improved bonding reliability at a ball joint in a high-temperature high-humidity environment, and which is suitable to devices for in-vehicle use. A bonding wire for semiconductor devices, which comprises a Cu alloy core material and a Pd coating layer that is formed on the surface of the Cu alloy core material, and wherein the bonding wire contains In in an amount of 0.011-1.2% by mass and the Pd coating layer has a thickness of 0.015-0.150 μm. Consequently, the bonding life in a ball joint in a high-temperature high-humidity environment is improved, and the bonding reliability is able to be improved. If the Cu alloy core material contains one or more elements selected from among Pt, Pd, Rh and Ni respectively in an amount of 0.05-1.2% by mass, the ball joint reliability in a high temperature environment at 175°C or more is able to be improved. In addition, if an Au superficial layer is additionally formed on the surface of the Pd coating layer, wedge bondability is improved. |