近化学计量比LiNbO_3晶体的坩埚下降法生长  

BRIDGMAN GROWTH OF NEAR-STOICHIOMETRIC LiNbO_3 SINGLE CRYSTALS

作　　者：陆宝亮[1] 徐家跃[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,浙江德清313216

出　　处：《硅酸盐学报》2004年第3期255-258,共4页Journal of The Chinese Ceramic Society

摘　　要：报道了化学计量比LiNbO3(stoichiometriclithiumniobate ,SLN)晶体的坩埚下降法生长。采用一致融熔成分铌酸锂籽晶 ,以K2 O为助熔剂 ,在自制的坩埚下降炉内生长SLN晶体。最高炉温控制在 13 0 0℃附近 ,固液界面处的纵向温度梯度为 40～ 60℃ /cm ,坩埚下降速率小于5mm/d ,在密闭的铂坩埚中 ,成功地生长出尺寸为2 5mm× 40mm的近化学计量比铌酸锂单晶。测得晶体的Curie温度为 190℃ ,利用有关公式计算出所得晶体的n(Li) /n(Li+Nb)为 0 .495 6,研究了熔体的析晶行为及晶体的宏观缺陷。The Bridgman growth of stoichiometric lithium niobate (SLN) single crystal was introduced. Using congruent lithium niobate (LN) as seed and K2O as flux, SLN was grown in a home-made Bridgman furnace. The SLN crystal with the size of φ25 mm × 40 mm was successfully obtained in a sealed Pt crucible under the growth conditions of the maximum furnace temperature 1300°C, the axial temperature gradient at the solid-liquid interface 40-60°C/cm, and the pulling-down rate less than 5 mm per day. The Curie temperature measured of as-grown SLN crystal is 190°C, and the n(Li)/n(Li+Nb) is calculated to be 0.4956. The crystallization behavior of high-temperature solution and the macro-defects of as-grown SLN crystal were also investigated.

关 键 词：铌酸锂 化学计量比 晶体生长 坩埚下降法 助熔剂 

分 类 号：O782[理学—晶体学]