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As one of the four key basic materials in the field of microelectronic packaging, Bonding wire is the internal lead to realize the electrical interconnection between chip and lead frame. Its quality directly determines the performance of microelectronic packaging products. As a non-traditional bonding wire, silver alloy wire has excellent conductivity, ductility, high reflectivity and excellent performance. It is the main direction to replace traditional bonding wire in the future. However, the bonded wire with high silver content is prone to silver ion migration under wet conditions, and is prone to surface discoloration caused by sulfide and oxygen corrosion in the air, which affects the reflectivity, long-term reliability and service life of the silver wire. In this paper, EDS, tensile tester, Color difference spectrometer were used to analyze the anti-corrosion ability and wire pull of 98.5% Ag / 1.5% Pd alloy silver bonding wire before and after treatment, and spectroradiometer was used to compare the reflectance of silver alloy wire in the air after one month of corrosion before and after treatment. Finally, after 85 °C /85%RH constant temperature / humidity experiment, test its conductivity and luminous flux. The results showed that the wire pull of the silver alloy wire before and after treatment was 9.60gf and 9.30gf, and after 85 ° C / 85% RH experiments, the difference in conductivity between the silver alloy wires before and after treatment was only 0.27%, and the difference in light attenuation was 0.72%. Finally, based on the new environmental protection passivation process of trivalent chromium cathode, a kind of smooth and compact silver based bonding wire coated with nano biofilm can be obtained, and its standards are in line with the national standards.

With excellent conductivity, ductility, reflectivity and low-cost advantages, silver bonding wire is a more competitive material which can replace the gold wire. It is widely used in display LED and storage fields. However, the key to the application of silver bonding wire is to solve the problem of sulfidation, which causes failure and discoloration. In this paper, a kind of anti-sulfidation film of the silver bonding wire is prepared by using the self-formulated passivation process, with different current densities. The results show that the a smooth and dense passive film covers the surface of the silver bonding wires after the treatment; TEM shows that the thickness of the anti-sulfidation passive film is about 3 nm, which provides excellent anti-sulfidation performance. In addition, the lumen reaches 123.45lm, rising by 1.2% over untreated in LED device; lumen increases by 1.1% compared with unpassivated silver bonding wire after sulfidation test. Therefore, passivation process can solve the application of anti-sulfidation of silver alloy bonding wire.

Silver bonding wire has excellent electrical conductivity, ductility and Reflective performance, the price is much lower than conventional gold wire, could be widely used in LED, IC and other fields. However, Silver bonding wire is very easy to react with oxygen and hydrogen sulfid, so as to lose its original reflective and reduce product performance. In this study, a kind of environmentally friendly organic treatment solution is employed to the surface of different silver alloy wires with high content of silver (>98%) by cathodic passivation, and the silver alloy wire before and after the treatment was examined for surface stability and wire bondability. In the result, the untreated silver alloys were significantly improved in surface stability than those of untreated silver alloy wires. It was also found that no any impurities was introduced after the treatment. As a result, a silver wire with silver content of 99% is used to check the wire bonding performance on the FAB and wire pull stress, it is found that the bonding performance of the treated silver alloy wire is the same as that of untreated, indicating that the treatment is a good suitable for improving in LED&IC package.