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铌酸锂 (LiNbO3 )单晶是目前在声表面波和声体波等器件制作方面应用得十分广泛的一种晶体。经激光探针研究证实 ,Y41°铌酸锂单晶在此方向上具有优良的漏声表面波特性 ,其漏声表面波机电耦合系数大 (约为 1 7.2 % ) ,传播损耗较低以及良好的温度系数 ,引起器件制作方面极大的关注。Y41°铌酸锂单晶的生长 ,改变了靠旋转切割c轴、Y 1 2 8°铌酸锂晶体 ,得到Y41°铌酸锂基片的现状 ,提高晶体的利用率 ,切割加工更方便可靠 ,更有效地满足漏声表面波器件制作的要求。本研究采用电阻加热提拉法生长Y41°铌酸锂单晶 ,借鉴我所其他方向铌酸锂单晶生长的成熟工艺措施 ,经过多炉次的试验 ,设计制作出适宜Y41°铌酸锂单晶生长的温场结构 ,寻找到合适的温度梯度 ( 2 0～ 1 0 0℃ /cm)进行生长 ,并确定相应的关键工艺参数 ,解决了Y41°铌酸锂单晶生长中 ,易出现孪晶、尾部易扭曲、易开裂等技术问题 ,成功生长出77mm× 70mm以上宏观完整性好的优质Y41°铌酸锂单晶。
Lithium niobate (LiNbO3) single crystal is currently a very wide range of applications in the production of surface acoustic wave and acoustic wave devices such as a crystal. The laser probe study confirmed that the Y41 ° lithium niobate single crystal has excellent characteristics of surface acoustic wave leakage in this direction, the leakage acoustic surface wave electromechanical coupling coefficient (about 1 7.2%), low propagation loss and Good temperature coefficient, causing great concern in the production of devices. The growth of Y41 ° lithium niobate single crystal changes the current state of Y41 ° lithium niobate substrate by rotating the c-axis and Y 1 2 8 ° lithium niobate crystals to improve the utilization of the crystal and make the cutting more convenient and reliable , More effectively meet the requirements of the surface acoustic wave device production. In this study, the Y41 ° lithium niobate single crystal was grown by resistance heating and pulling method. Based on the mature technology measures of growing LiNbO3 single crystal in other directions, after more heat tests, the Y41 ° lithium niobate single Crystal growth temperature field structure, looking for a suitable temperature gradient (20 ~ 100 ℃ / cm) growth, and to determine the corresponding key process parameters to solve the Y41 ° lithium niobate single crystal growth, prone to twin Crystal, the tail easily twisted, easy to crack and other technical problems, the successful growth of 77mm × 70mm above the macro-integrity of good quality Y41 ° lithium niobate single crystal.