| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve adhesion between a copper core 1 and a coating layer 2. <P>SOLUTION: A bonding wire W has a wire diameter L in a range of 12 μm or more and 50.8 μm or less, serving to connect an electrode a for an integrated circuit element and a conductor wire c of a circuit wiring board using a ball bonding method. The circumference surface of a core 1, made of copper 99.99% wt.% or more, is roughened to Ra:0.1-0.4 μm by a treatment, such as bead blasting, shot-blasting, acid treatment or strike plating. A coating layer 2, which has oxidation resistance based on Pd and Pt, is formed on the roughened core circumference surface. The adhesion is improved because the adhesion area between the core circumference surface and the coating layer 2 is increased by the roughening. Hence, the cracking of the coating layer, due to the bending of the wire, does not readily occur, and a Cu surface is difficult to be exposed on the surface of the coating layer. This prevention of exposure allows the coating layer to be thinner. Accordingly, the hardening of FAB being less likely, and economic efficiency is improved. <P>COPYRIGHT: (C)2012,JPO&INPIT |
