声表面波用压电晶体的新进展(英文)  

Recent Developments of Piezoelectric Crystals for SAW Applications

作　　者：徐家跃[1] 武安华[1] 陆宝亮[1] 张爱琼[1] 范世■ 夏宗仁[2] 

机构地区：[1]中国科学院上海硅酸盐研究所,上海200050 [2]中电科技德清华莹电子有限公司,德清313216

出　　处：《人工晶体学报》2004年第4期553-558,共6页Journal of Synthetic Crystals

摘　　要：报道了我们在Li2 B4O7、Sr3 Ga2 Ge4O14 、LiNbO3 、LiTaO3 等声表面波用压电晶体材料方面的最新研究进展。采用改进型坩埚下降法成功生长了直径 3～ 4英寸的Li2 B4O7晶体 ,并实现了批量生产。作为硅酸镓镧系列新型压电晶体之一 ,Sr3 Ga2 Ge4O14 晶体具有最大的压电系数。报道了直径 2英寸Sr3 Ga2 Ge4O14 晶体的生长结果 ,测试了该晶体的压电性能。在CO2 (90 % )、H2 (10 % )混合气氛中 ,分别在 70 0℃和 4 5 0℃下对LN和LT晶片进行化学还原处理 ,成功制备了 3英寸LN和LT低静电黑片 ,不仅减少了器件制作工序 ,而且使成品率提高了 5～ 8百分点。此外 ,在密封坩埚中生长了低静电LiNbO3 晶体 ,观察到一些新的现象。Recent developments of piezocrystals, Li_2B_4O_7, Sr_3Ga_2Ge_4O_(14), LiNbO_3 and LiTaO_3 in our laboratory were reported in this paper. Li_2B_4O_7 single crystals of 3 to 4 inches in diameter have been grown successfully by the modified vertical Bridgman method and mass production of large size Li_2B_4O_7 crystals has been realized. Sr_3Ga_2Ge_4O_(14) (SGG) crystal is a novel piezoelectric crystal with the largest piezoelectric constants among the langasite family. Bridgman growth of SGG crystal up to 2 inches in diameter has been reported and its piezoelectric properties have been measured. In order to improve the yield of SAW devices, pyro-free LiNbO_3 and LiTaO_3 wafers were prepared by chemical reduction at 700℃ and 450℃ respectively under a mixed atmosphere of CO_2 and H_2. Bridgman growth of LiNbO_3 crystals was also investigated and some new phenomena were observed.

关 键 词：声表面波 压电晶体 改进型坩埚下降法 晶体生长 LiB4O7 硼酸锂 低静电黑片 Sr3Ga2Ge4O14晶体 

分 类 号：O799[理学—晶体学]