| 摘要 |
PURPOSE:To manufacture a fine copper wire excellent in deformability and having high wire strength, by casting an ingot in which trace amounts of Nb, Mg, Ca, etc., are added to high-purity Cu under vacuum or nonoxidizing atmosphere and then by applying wire drawing to the above at a proper draft. CONSTITUTION:The ingot consisting of 0.1-9ppm, in total, of 0.1-4.5ppm Nb and 0.1-9ppm of one or more elements among Mg, Ca, rare earth elements, Hf, V, Ta, Pd, Pt, Au, Cd, B, Al, In, Si, Ge, Pb, P, Sb, and Bi and the balance Cu is cast under vacuum or nonoxidizing atmosphere. It is preferable that, as the above Cu, that of >=99.999wt% purity, desirably >=about 99.9999%, is used. The above ingot is repeatedly subjected to wire drawing and annealing treatment to be formed into the prescribed wire diameter. At this time, at least final draft is regulated to 70-99.99% and 2-20% elongation is provided by means of annealing treatment. In this way, the fine copper wire combining superior deformability with high wire strength, causing neither softening at ordinary temp. nor sag of loop, having excellent shape of ball, and suitable for ball bonding wire can be obtained. |
