| 摘要 |
PURPOSE:To manufacture a lead frame material causing no deformation to a wire bonding part resulting from blanking by applying compressive stress in the longitudinal direction of the surface layer part of an alloy material and also applying tensile stress in the longitudinal direction of the central part contiguous to the surface layer part, respectively, at the time of manufacturing lead frame. CONSTITUTION:A lead frame material consisting of a cold-rolled sheet-like Ni alloy is subjected to cold tension and cold repeated bending simultaneously by means of a tension leveler, by which compressive stress is established in the longitudinal direction of the surface layer part, and simultaneously, tensile stress is applied in the longitudinal direction of the central part contiguous to the surface layer part. At this time, the maximum difference in sheet thickness-direction distribution between the applied longitudinal-direction stresses are regulated to >=2kg/mm<2>. By this method, the lead frame material causing no deformation, such as difference in level, to the wire bonding part at the time of blanking can be obtained. |
