中文摘要：

四硼酸锂（Li2B4O7，LBO）晶体是一种性能优异的压电基片材料，坩埚下降法生长的直径为76mm LBO晶体已成功应用于声表面波（SAW）和体波（BW）器件。由于硼酸盐熔体粘度大、晶体易开裂，生长直径为102mm的LBO晶体产业化还有很大难度。本工作根据坩埚下降法技术特点，提出了转向生长LBO晶体的工艺方案，成功生长出60mm×110mm×120mm板状晶体。晶体沿[001]方向快速生长，侧面主面为（110）。生长的板状晶体经准确定向、加工后即可获得高度60mm、直径为102mm（4in）的[110]取向LBO晶体，生长速率和晶体产率较传统方法都有显著提高。

英文摘要：

Lithium tetraborate （Li2B4O7： LBO） single crystal is a superior substrate material for surface acoustic wave （SAW） and body acoustic wave （BAW） devices. LBO crystals with the diameter of 76 mm have been mass-produced by the modified vertical Bridgman method. However, the yield is rather low for LBO crystals with the diameter of 102 mm due to high viscosity of its melt and cracking. In this paper, LBO crystals with the diameter of 102 mm were prepared by an alternative method based on the characteristic feature of the vertical Bridgman method. LBO block with the sizes of 60 mm× 110 mm×120 mm was grown along [001] direction with （110） main face, and the as-grown block was cut and ground to a [110]-oriented LBO boule with the diameter of 102 mm. The growth rate and the yield are improved.