Gold alloy wire bonding

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PROBLEM TO BE SOLVED : To provide the gold-alloy thin wire for bonding the sufficient mechanical characteristics without decreasing the junction strength with chip electrodes even when the space between the chip electrodes and the external width of a lead frame are narrowed furthermore. SOLUTION : Adjustment is performed so than palladium has 0.02-2.0 wt.%, germanium has 0.01-1.5 wt.% and the remaining part becomes gold and the unavoidable impurities of these materials. In addition, one or more kinds of materials selected from the group comprising beryllium, magnesium, calcium, strontium, barium, gallium, indium, thallium, tin, lead, yttrium and other rare- earth elements are added so that the total amount becomes 1-20 ppm. Then the mechanical characteristics of the alloy thin wire are further improved. Furthermore, it is recommendable that the weight ratio of palladium and germanium is set at 1 : 0.2-1 : 0.8.