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

Abstract The surface tension of Ga 2 O 3 melt is successfully measured using a drop-weight method in an optical floating-zone furnace that we have developed. The method is verified to be feasible by measuring the surface tension value of TiO 2 melt and then comparing it with values in previous reports determined by other methods. We find that the surface tension of Si-doped Ga 2 O 3 melt increases with the decrease in the Si doping concentration and reaches 527.9 mN m −1 for pure Ga 2 O 3 melt. The surface tension of the unintentionally doped Ga 2 O 3 melt is also measured to be 519.3 mN m −1 in the presence of some common contaminants appearing in Czochralski and edge-defined film-fed growth methods, including Ir, Al, and Si.