Growth of 2-inch diameter Mg₂Si crystal by the VGF method under Ar normal pressure

Abstract

A 2-inch diameter Mg₂Si crystal was synthesized via the vertical gradient freeze (VGF) method in an open-tube system using pyrolytic boron nitride crucibles coated with boron nitride. Using this open-tube system, Mg evaporation was significantly prevented under Ar gas flow. Many grain boundaries were observed at the crystal cross section. A 5-mm square wafer without grain boundaries was cut out from the crystal and characterized by X-ray rocking curve (XRC) analysis, exhibiting a sharp single peak with a full width at half maximum (FWHM) of 50.4 arcsec. This indicates good crystallinity of the single crystalline area of the synthesized crystal.