New Surface Treatment Method for Silver AlloyWire and Its Performance Evaluation

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.