β-Zn_3BPO_7晶体的提拉法生长研究

Study on Pulling Growth of β-Zn_3BPO_7 Crystal

采用提拉法生长 β Zn3BPO7(简称ZBP)晶体。研究了生长工艺 ,用 [2 10 ]方向的籽晶 ,获得了尺寸为 35mm× 2 0mm× 10mm的单晶 ,该晶体无色透明 ,不开裂 ,呈现发育完好的 { 0 0 1}板面。通过设计特殊的温场以及在生长结束后采用适当的热条件有效地抑制了相变的发生。生长过程中靠近液面的温度梯度为 30～ 6 0℃ /cm ,晶体转速为 15～ 2 5r/min ,提拉速度不大于 1mm/h。ZBP晶体有宽的透光范围 ,它的紫外吸收边为 2 4 0nm。ZBP晶体不潮解 ,其莫氏硬度为 5Mohs。

Single crystals of β Zn 3BPO 7(ZBP) have been grown by Czochralski method.The growth conditions were investigated,the transparent and crack free crystal of 35mm×20mm×10mm with well developed {001} pinacoid was obtained using a [210] seed.The phase transition was effectively suppressed by adopting special temperature distribution and after growth heat treatment.The pulling rate is less than 1mm/h,the temperature gradient near the solid liquid interface is 30-60℃/cm and the rotation rate is 15-25r/min.ZBP crystals exhibits wide transparent range,its absorption edge is 240nm.ZBP crystal is insensitive to water,its hardness is 5Mohs.