Temperature and chemical effects on the interfacial energy between a Ga-In-Sn eutectic liquid alloy and nanoscopic asperities.

The interfacial energies between a eutectic Ga-In-Sn liquid alloy and single nanoscopic asperities of SiO , Au, and PtSi have been determined in the temperature range between room temperature and 90 °C by atomic force spectroscopy. For all asperities used here, we find that the interfacial tension of the eutectic Ga-In-Sn liquid alloy is smaller than its free surface energy by a factor of two (for SiO ) to eight (for PtSi). Any significant oxide growth upon heating studied was not detected here, and the measured interfacial energies strongly depend on the chemistry of the asperities. We also observe a weak increase of the interfacial energy as a function of the temperature, which can be explained by the reactivity between SiO and Ga and the occurrence of chemical segregation at the liquid alloy surface.