Quantitative characterization of 96.5Sn3.5Ag and 80Au20Sn optical fiber solder bond joints on silicon micro-optical bench substrates

Stress analysis of optical fiber solder bond joints on silicon micro-optica l bench substrates under thermal cycle loading was investigated using two-d imensional (2-D) and three-dimensional (3-D) finite element analyses. Finit e element simulations were carried out to investigate the effect of the dis tance between the fiber and the silicon substrate for planar and v-groove s older attachment geometries. It was found that the maximum stress-strain al ong the interface of the solder and silicon substrate increases as the dist ance between the fiber and substrate decreases for both geometries. The sol der bond strength under thermal loading was also examined to determine the influence of alternative solder material. Favorable results were obtained f or 96.5Sn3.5Ag solder as compared to 80Au20Sn solder. If adequate space is provided between the fiber and silicon v-groove inclined walls, the reliabi lity of the v-groove geometry is projected to be comparable to an optimally designed planar bond joint geometry.