Technical Articles From National Chiao Tung University

Anisotropic grain growth and crack propagation in eutectic microstructure under cyclic temperature annealing in flip-chip SnPb composite solder joints

Jun 19, 2014 | Y.C. Liang, H.W. Lin, H.P. Chen, C. Chen, K.N. Tub, Y.S.Lai

For high-density electronic packaging,the application of flip-chip solder joints has been well received in the microelectronics industry. High-lead(Pb) solders such as Sn5Pb95 are presently granted immunity from the RoHS requirements for their use in high-end flip-chip devices, especially in military applications. In flip-chip technology for consumer electronic products, organic substrates have replaced ceramic substrates due to the demand for less weight and low cost. However, the liquidus temperatures of high-Pb solders are over 300°C which would damage organic substrates during reflow because of the low glass transition temperature. To overcome this difficulty, the composite solder approach was developed......