| 摘要 |
PROBLEM TO BE SOLVED: To provide a bonding wire in which copper is not exposed to the ball surface, when forming a ball of a palladium coated copper bonding wire.SOLUTION: In a bonding wire where the outside of a core material 10 mainly composed of copper is coated with palladium, an oxidation discoloration part 50 occurring on the surface, when copper is heated in the atmosphere at a heating temperature and for a heating time that cause red oxidation discoloration, has a maximum width of 1 μm or less in the circumferential direction. |
