3:30 PM - 3:45 PM
▼ [14p-2K-8] Piezoelectric Ca3TaAl3Si2O14 (CTAS) Single Crystals for High Temperature Sensors
Keywords:Piezoelectric,Langasite,High temperature sensors
The piezoelectric langasite family is attracting much attention for high temperature sensor applications. These crystals do not present any phase transition up to their melting point (1300-1500oC), exhibit good piezoelectric properties, are not pyroelectric, and can be grown by the Czochralski technique. Among them, the ordered Ca3TaAl3Si2O14 (CTAS) crystal is of particular interest, since it is Ga-free and exhibits high resistivity and thermal stability of dielectric and electromechanical properties. In this work, high quality CTAS single crystals have been grown successfully by the Cz method. The effect of growth conditions on their piezoelectric, electric and optical properties has been examined for the first time in detail. A notable influence is observed, especially in resistivity, which could be increased beyond the reported values for the same CTAS single crystals.