2000 年 27 巻 2 号 p. 76-81
A Macro defect-free langasite (La_3Ga_5SiO_<14>) crystal 3" in diameter was grown along its Z-axis by the conventional Czochralski technique. The grown crystal represents clear faceting on (0001) and (011^^-0) faces, forming a basal Z plane and hexagonal columnar Y plane, respectively. Holding melt at the temperature close to the equilibrium melting temperature makes the supercooling degree appropriate for the development of the (0001) facet plane. A good balance between convection and surface stability of (0001) plane leads to the uniform interface during growth. The homogeneity in composition was investigated two-dimensionally by the X-ray Bond diffraction method. The congruent melt composition for langasite is also discussed relative to the stoichiometric composition.