Simulation of bonding wire deformation in random vibration

Compared with plastic package, the reliability of ceramic package is very high. With the ever-increasing capabilities of integration, circuits using ceramic package have come the requirements on electronic packaging for providing higher density, higher I/O. For ceramic package using wire bonding, there will be more and more bonding wires because of higher density, higher I/O and input/output pins. In order to give a reasonable design of these bonding wires, there will be three even four layers bonding fingers. Thus, the space between two bonding wires nearby is very small and there loops are very high. Also, bonding wires are very long. However, bonding wires with high loop and long distance have very low reliability. It is very important to know how bonding wires will act when the circuits include these bonding wires are undergoing reliability test. And there will be deformation when bonding wire is tested in random vibration. Therefore, giving simulation results of deformation is necessary to investigate the reliability of bonding wires. Finite Element (FE) simulation is an effective approach to investigate the deformation trend of bonding wires in random vibration. And simulation of bonding wires in random vibration will be proposed using FE software in this paper. Instead of building full package model, the longest bonding wire is built to evaluate deformation and power spectral density (PSD) is applied in the modeling. By comparing the simulation results, the deformation of single wire can be used to investigate the full package model. In addition, deformation of bonding wires with different distance, different loops, different elastic modulus and different wire diameters is compared. Simulation shows that wires with short distance, low loop, high elastic modulus and big wire diameter will have smaller deformation in random vibration. High-Speed micro-camera test is used to verify the simulation results. According to the results we can see that the simulation - esults are fit to the test very well. Finally, constructive suggestion is proposed, which will improve the reliability of bonding wire.