The invention relates to a low-cost packaging bonding silver
alloy wire and a preparation method thereof and belongs to the technical field of bonding wire
processing. The silver
alloy wire is composed of the following
metal materials by weight ratio (wt%): less than 1% of Au, 1000-10000ppm of Pd, 10-200ppm of Pb, 5ppm of Mg and the balance of Ag. The method comprises the following steps: preparing materials; preparing intermediate
alloy; performing vacuum melting and pull
casting; making an alloy bar into a 2 to 4mm alloy
bus by using a coarse drawing
machine unit; performing intermediate on-line annealing on the alloy
bus; drawing the alloy
bus subjected to the intermediate on-line annealing into micro filaments with diameters of 0.015-0.030mm by a continuous drawing
machine unit; and performing stabilized on-line annealing on the micro filaments to make silver alloy wires. The method adopts a principle of
physical chemistry in
metallurgy to design a simple and easy alloying component, greatly improves the content of
palladium, adds the intermediate alloy to the liquid silver to significantly improve the
oxidation resistance of the silver alloy, The different amount of
magnesium is added by the method of the intermediate alloy to adjust the strong
plasticity of the alloy wire, and a trace of Pb elements are added to enhance ball stability.