Recently, FIB (Focused Ion Beam) technology is used for preparation of TEM specimen.  On the other hand, the cross-sectional microstructure at the soft metal interface with FIB technology was different from the cross-sectional microstructure with conventional polishing and etching method.  Therefore the cross-sectional microstructure at the soft metal interface such as Cu/Sn interface with FIB technology was investigated as compared with conventional polishing and etching method.
In this study, 2 kinds of specimen were prepared.  One was Cu/Cu diffusion bonding specimen.  Another was Cu/Sn soldering specimen.
First step of FIB technology was making the thin leaf.  Second step of FIB was polishing with using FIB equipment.
And first step of conventional polishing and etching method was polishing with emery paper.  Second step was polishing with alumina powder.  Final step was etching with using etchant.
Sound cross-sectional microstructure at the soft metal interface was obtained with FIB technology.  As compared with conventional polishing and etching method, this sound cross-sectional microstructure at the soft metal interface made the joining mechanism clear.