| 摘要 |
PROBLEM TO BE SOLVED: To provide a bonding wire which has high strength even when it is fined and suppress the deterioration of bonding strength even at a high temperature by processing an alloy, which is prepared by adding Pt or Pd or both and at least one of the following, Be, Ge, Ca, La, Y and Eu, by a specified ratio to highly pure gold, into fine wire which has a prescribed elongation percentage and Young's modulus. SOLUTION: At least Pt or Pd or both are added by 0.1-2.2wt.% and at least one of the following, Be, Ge, Ca, La, Y and Eu, by 0.0001-0.00005wt.% to a highly pure gold of 99.99wt.% or more, and the material is melted by high frequency in a tube-shaped graphite crucible 2. Then, high frequency heating coil 3 is shifted from the bottom edge of the graphite crucible 2 to the top edge at a speed of 50mm/min. so as to cool and solidify the melted material 1, and ingot is casted. After rolling the ingot by using a groove roll, the material is processed into a wire with a diameter of 20μm and is annealed to have an elongation percentage of 3-8% and a Young's modulus of 6800-9000 kgf/mm<2> . Thus, the fine wire which has a prescribed strength even it is fine, allows less bonding strength deterioration even at a high temperature and is strong against vibration is provided. |
