Low-cost packaging bonding silver alloy wire and preparation method thereof

Abstract

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.

Description

technical field [0001] The invention relates to a low-cost packaging and bonding silver alloy wire and a preparation method thereof, belonging to the technical field of bonding wire processing technology. Background technique [0002] There are many kinds of microwires for bonding, such as gold wire, silver wire, copper wire, palladium-plated copper wire, silver-plated gold, etc., but the overall performance is still better than gold wire, especially for many years, various bonding equipment is also suitable for gold wire. The stability of the gold wire is also recognized. Although the cost of newly developed single crystal copper wire has been greatly reduced compared with gold wire in recent years, it is difficult to popularize and apply it at present due to the strong toughness of copper wire, especially its poor oxidation resistance. Palladium-plated copper wire, silver-plated gold, etc. have solved the oxidation problem of the bonding wire, but the electroplating cause...

AI Technical Summary

Problems solved by technology

[0005] The gold content in the currently developed silver alloy bonding wire reaches 20-55%, such as the CN102776405A patent, whose gold content reaches 20-30%, and the CN104388861A patent, whose gold content reaches 35-55%, and other trace elements are also added in these materials. relatively high cost

There are also inventions that use electroplating to plate gold on the surface of pure silver wire to improve material performance, but the stability of the coating and environmental protection requirements restrict the use and development of materials.

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