EFFECT OF THE INTERMETALLIC COMPOUNDS ON THE JOINT STRENGTH OF THE OPTICAL MODULE

摘要

Al / Au stud bumps and Cu / Sn-Pb solders were adopted, and aged for up to 900 hours to analyze the effect of intermetallic compound (IMC). The joint strength decreased with aging time. The diffraction patterns of Ci_6Sn_5, scallop-shape IMC and planar-shape Cu_3Sn were observed by transmission electron microscopy (TEM). IMC between Au stud bump and Al pad was identified as AlAu_2. The formation of Kirkendall voids with the growth of IMC at the interface between solder and under bump metallurgy (UBM) was confirmed.