The surface tension of Ga₂O₃ melt measured by a drop-weight method in an optical floating-zone furnace

Abstract

The surface tension of Ga2O3 melt is successfully measured by drop weight method in optical floating-zone furnace (DW-OFZ method) that we have developed. Such method is verified to be feasible by measuring the surface tension value of TiO2 melt and then comparing it with the ones in the previous reports determined by other methods. We found that the surface tension of Si-doped Ga2O3 melt increases with the decrease of Si doping concentration and reaches 529.5 mN/m for pure Ga2O3 melt. The surface tension of the unintentionally doped (UID) Ga2O3 melt is also measured to be 515.6 mN/m in the presence of some common contaminants appeared in Czochralski (CZ) and edge-defined film-fed growth (EFG) methods, including Ir, Al, Si and so on.