Interfacial Microstructures and Kinetics of Sn2.5Ag0.7Cu/Cu
The interfacial microstructures and kinetics of low Ag content Sn2.5Ag0.7Cu/Cu solder joint were investigated by the X-ray diffraction, scanning electronic microscope and energy spectrum analysis during the isothermal aging. The results show that the interfacial microstructures of the Sn2.5Ag0.7Cu/Cu solder joint are composed of Cu3Sn and Cu6Sn5 after soldering. With the aging time increasing, the intermetallic compound (IMC) pattern of the solder joint interface can be changed from the scallop-like to the shape-layer, and the growing dynamics is coincidence with the law of parabola and its growing behavior is controlled by diffusion. The growing activation energies values of Cu3Sn and Cu6Sn5 layer at the Sn2.5Ag0.7Cu/Cu solder joint are 82.4kJ/mol and 69.6kJ/mol respectively.
Chengming Li, Chengbao Jiang, Zhiyong Zhong and Yichun Zhou
Y. L. Wang et al., "Interfacial Microstructures and Kinetics of Sn2.5Ag0.7Cu/Cu", Materials Science Forum, Vol. 687, pp. 112-116, 2011