Pure silver wire bonding on palladium finishing for automotive application

Abstract

Material selection in wire bonding requires the best match of electrical characteristics, mechanical properties and material cost to reach high performance and competitiveness in automotive market. Silver alloy is emerging to replace gold and copper thanks to its softness, however it reveals high resistivity when bigger wire diameter is needed for high current applications. The aim of this work is to introduce pure silver wire bonding on palladium finished pads as new alternative able to combine low electrical resistivity and excellent reliability performance. For this purpose, process capability and reliability tests outcome are reported to characterize the new material during product operating life.