Ta2O5单晶激光法生长及其介电性质研究

Growth and dielectric properties of Ta2O5 single crystals grown by laser heated pedestal growth technique

Ta2O5 single crystals have been grown by the laser heated pedestal growth (LHPG) technique up to several centimeters length with diameter of 1.1 mm. The crystal, characterized by X-ray diffraction, dielectric measurement, and thermal expansion analysis, has Htri-Wa2O5 symmetry. Dielectric permittivity, loss tangent along 001] and 110] direction were investigated over the temperature range from -180℃ to 100℃. Large dielectric anisotropy in 2O5 single crystal was observed. At room temperature, the dielectric permittivities (1 MHz) along 001] and 110] are 33.2 and 231.9, respectively. The reason of dielectric enhancement in Ta2O5 crystal grown by LHPG was also discussed.