Alloy phase formation in nanometer-sized particles in the In-Sn system

Alloy phase formation in the In-Sn binary system has been studied as a function of the particle size by in situ transmission electron microscopy at room temperature. In approximately 16-nm-sized particles, alloy phases formed were essentially the same as for those in bulk material. However, in particles less than approximately 10 nm in size, the formation of a liquid phase, which is not an equilibrium phase in bulk at room temperature, was confirmed. The formation of the liquid phase can be ascribed to the large suppression of the eutectic temperature associated with the size reduction.