硅酸镓镧结构的新型压电晶体的研究进展

新型压电晶体La3Ga5SiO14因其低声速、零温度切向和良好的高温稳定性受到关注，但是昂贵的Ga2O3原料阻碍了它的工业应用。通过离子置换可获得具有langasite结构的多种新型压电晶体。综述介绍了置换La，Ga，Si形成的新型压电晶体的最新研究进展，比较分析了不同晶体的优势及其存在的问题。在这些新晶体中，由于Sr3Ga2Ge4O14（SGG)具有熔点较低、性能较高的综合优势，它有可能成为新一代表面波器件的重要候选材料。与提拉法相比，采用增蜗密封的下降法生长SGG单晶；可以显著提高晶体产率，降低成本。

RECENT DEVELOPMENTS OF NEW PIEZOELECTRIC SINGLE CRYSTALS WITH La3Ga5SiO14 STRUCTURE

New piezoelectric crystal La 3Ga 5SiO 14 has attracted much attention due to its low acoustic velocity, zero temperature coefficient delay and excellent thermal stability at high temperature. The disadvantage for industrial application is the expensive price of raw materials, especially for Ga 2O 3. A series of new piezoelectric single crystals with langasite structure can be obtained by ion replacement. Progress on the research of single crystals with La 3Ga 5SiO 14 structure formed by the replacements of La, Ga and Si are reviewed in this paper. The growth methods, growth parameters and piezoelectric properties are comparatively discussed. Compared with other crystals, Sr 3Ga 2Ge 4O 14 (SGG) has lower melting point and better performance. Thus, SGG is the most potential candidate material for the new type SAW devices. Compared with Czochralski method SGG single crystal growth with crucible capsuled vertical Bridgman method can improve crystal production and lower the cost efficiently.