This study focused on the Au Au junction, using a sub-micron gold particle with low temperature sintering. The mechanical properties and the micro-structures were measured with the microbumps of the Au sintered compact, and mechanical shear fatigue tests for flip-chip specimens were then carried out. The cluster structure of the sintered bump heated at 220°C possessed ductility and turned to a grain growth structure with thermo-compression, resulting in a densely packed structure. In the mechanical shear fatigue test for the flip-chip specimens, the number of cycles to failure for the sintered bump was superior to that of a Sn-Ag alloy solder.
