Shape-controlled crystal growth of Sr<inf>3</inf>NbGa<inf>3</inf>Si<inf>2</inf>O<inf>14</inf> and Sr<inf>3</inf>TaGa<inf>3</inf>Si<inf>2</inf>O<inf>14</inf> piezoelectric single crystal by micro-pulling-down method

Abstract

We have grown the shape-controlled Sr ₃ NbGa ₃ Si ₂ O ₁₄ (SNGS) and Sr ₃ TaGa ₃ Si ₂ O ₁₄ (STGS) langasite-type crystals by the μ-PD method. Columnar-shaped SNGS and STGS crystals were grown using the Pt-Rh crucible with a columnar die in 3 mm diameter. Grown crystals indicated high transparency and approximately 3 mm diameter. Chemical phases of grown crystals were identified as a single phase of langasite-type structure. The lattice parameters of grown crystals were almost consistent with those of crystals grown by Czochralski (Cz) method. In the X-ray rocking curve measurements, the grown crystals indicated equivalent crystallinity to the crystal grown by Cz method.