Structural Assessment of Lead Free Solder Joint of Miniaturized Electronics Assembly

This paper presents a study on structural assessment of ultra-fine package assembly with nanocomposites lead free solder joint after reflow soldering process.In this work, various nanoparticles (i.e.TiO 2 , Fe 2 O 3 and NiO) with different weight percentage (i.e., 0.01, 0.05 and 0.15 wt.%) were successfully incorporated into SAC305 solder paste using a mechanical solder paste mixer to synthesize novel lead-free composite solders.Effects of the nanoparticles addition on quality of joining and fillet height between various weightage (wt.%) for the ultra-fine package assembly in the reflow soldering process have been investigated by using a scanning electron microscope (SEM) system equipped with an energy dispersive X-ray spectroscopy (EDS) and XTV 160 xray inspection system.Experimental results show the addition of TiO 2 , Fe 2 O 3 and NiO nanoparticles with 0.15wt.%,0.05wt.%and 0.01wt.%,respectively, produce the best fillet height of each composition of nanoparticles solder paste.Among all these new composition of nanoparticles solder paste, NiO nanoparticles reinforced solder paste with 0.01wt.%yielded the highest fillet height.The miniaturized solder joints do not cause any problem in terms of solder voids.The findings show the capability of the reflow soldering process in assembling miniaturized electronics assembly and expected to provide a reference in electronic package industry.