We have grown shape-controlled langasite-type crystals by the micro-pulling-down (μ-PD) method. Columnar shaped La 3Ta 0.5Ga 5.5O 14 (LTG), Ca 3NbGa 3Si 2O 14 (CNGS), Ca 3TaGa 3Si 2O 14 (CTGS), Sr 3NbGa 3Si 2O 14 (SNGS), and Sr 3Ta- Ga 3Si 2O 14 (STGS) crystals were grown using a Pt-Rh crucible with a 3-mm-diameter columnar die at the bottom. All grown crystals showed high transparency except for the peripheral area and diameter of approximately 3 mm. The chemical phases at the central parts of the grown crystals were identified as a single phase of langasite-type structure and their lattice parameters were almost the same as those of crystals grown by the Czochralski (Cz) method; however, some impurity phases were observed in the peripheral area. In X-ray rocking curve measurements, the grown crystals indicated equivalent crystallinity to the crystal grown by the Cz method. The piezoelectric constant d 11 of the CNGS crystal was 3.98 pC/N; this value is well correlated with those of previous reports.
|Number of pages||4|
|Journal||IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control|
|Publication status||Published - 2012|
ASJC Scopus subject areas
- Acoustics and Ultrasonics
- Electrical and Electronic Engineering