| 摘要 |
Degradation in the oxidation resistance of a core material (1) is controlled to the utmost, even when cracks form in a coating layer (2). A bonding wire (W) has a wire diameter (L) between 12 µm and 50.8 µm for connecting an electrode (a) of an integrated circuit element and a conductive wire (c) of a circuit wiring board by means of ball bonding. At least one or more selected from Au or a platinum group metal is added to the core material (1), which comprises at least 99.99 mass% of copper, to improve oxidation resistance, P is added to the core material (1) to improve electrical resistivity, and a coating layer (2) having oxidation-resistant Pt or Pd thickness (t) of 0.02 µm to 0.09 µm is formed around the entire outer circumferential surface of the core material (1). The bonding wire has high electrical resistivity due to the addition of the P and can be used for stable FAB formation using a spark that has a low current and short duration. Because Au or a platinum group metal is added to the core material (1) at such time, a compound is not formed with the P and the improvement in oxidation resistance is ensured. As a result, even when cracks form in the coating layer, degradation in the oxidation resistance of the core material that is caused by such cracking is controlled to the utmost. |
