| 摘要 |
PURPOSE:To inhibit the coarsening of the crystalline grains in a Cu material and to obtain a copper bonding wire capable of performing superior wire bonding by adding specific amounts of alkaline earth element or Zr to a high- purity copper material. CONSTITUTION:An electrodeposited material which is formed into >=99.9999wt.% purity by means of electrolytic refining is used, and at least one alkaline earth element or Zr is added by 0.0002-0.002% to the above. This addition is done by blending the previously refined copper alloy of alkaline earth element or Zr with the above copper material into the prescribed composition and performing refining by means of vacuum melting. Then, wire drawing and annealing are repeatedly applied to the resulting ingot by required times, by which the copper bonding wire is obtained. By this method, the growth of the crystalline grains in a ball neck part can be inhibited, and wire bonding excellent in bonding characteristics is made possible. |
