Modeling and reliability characterization of micro-coil springs for ceramic grid array integrated circuits

Micro-coil spring is a new technology for large-scale integrated circuit interconnection to replace traditional solder columns due to its ability to absorb the mechanical stress generated by external vibration and withstand the shear force caused by CTE mismatch. In this paper, the simulation platform was built to predict the thermal fatigue life, durable vibration capacity and high impact life of the solder joints of MCS interconnected structures, respectively. In the thermal cycling process, flexible micro-springs bear the lateral displacement, which effectively alleviated the thermal mismatch problem. In addition, longitudinal cracks of the solder joints of micro-springs were generated by S11. Based on the Darveaux model, the thermal cycling life of the micro-spring board-level interconnect was predicted to be 9934 cycles. The vibration fatigue simulation results showed that the RMISES were 4.969MPa and 3.629MPa for the MCS and solder, respectively.