Risk assessment for bonding wires instantaneous touch in high density packaging

This paper studies the risk assessment method of bonding wires instantaneous touch during mechanical shock tests. Under-damping vibration motion is used to describe bonding wire's motion state with mechanical shock loads. The influence of loop span, wire diameter and loop height on the amplitude and frequency of wire's vibration are analysed based on the results of finite element analysis and design of experiments. The detection experiments of bonding wire's instantaneous touch are conducted to get the vibration amplitude and vibration damping coefficient. Then, the risk assessment method is built by the analysis of simulation data and experiments data to evaluate the probability of adjacent wire's transient touch under mechanical shock load.