Microstructure of Electromagnetically Levitated Si Droplets Solidified on Copper Plate

Abstract

By combination of electromagnetic levitation and copper-plate quenching, deep undercooling and non-equilibrium solidification of Si melts were realized. Several different morphologies of Si solidified at different undercoolings were found on the quenched surfaces, including spherical non-faceted morphology, faceted dendritic morphology, octahedral morphology and other polyhedral morphology. The mixed microstructures consisting of non-faceted and faceted morphologies in one single sample provide direct evidence for the growth mode transition from a continuous form to a lateral form.