Finite element analysis for the wire bonding process and impact force variation

In this paper, a 2D model for the gold wire bonding process is created to simulate the processes of contacting, pressing and ultrasonic vibration applying through the LS-DYNA tool. The distribution of the stress and the strain of the bonding interface can be obtained. In order to describe the 3-D impact process which includes the golden ball, the lumped mass on the ball and on the bonding pad, the bonding head inertia moment is described by the lumped mass. The model is built to simulate the process of the capillary contacting the pad. The maximum impact force can be obtained and the impact force curve can also be obtained through various search velocities to approaching the pad. The results show that the FE model created for the bonding process including the impact process are correct and useful for the bonding structure design and bonding parameter setting.