摘要
高质量大尺寸氟化钙晶体是深紫外光刻、空天相机等高端应用不可或缺的光学材料,同时制备高质量大尺寸晶体也是晶体生长领域的难题。本文以数值手段分别模拟了3、7和20英寸(1英寸=2.54 cm)氟化钙晶体在不同生长阶段的传热、流动及相变过程。结果表明,晶体尺寸增加大幅加强熔体流动强度,而且造成坩埚外壁散热部分的面积急剧增加,由此引发固液界面局部凹陷、径向温差增大、晶体边缘-中心温差翻转、生长界面附近的轴向温梯大幅衰减等问题。此外,本文还就大尺寸氟化钙晶体生长中的坩埚下降速率和发热体功率的优化控制策略进行了探讨。
High-quality,large-size CaF_(2)crystals are urgently needed for advanced applications such as deep ultraviolet lithography and aerospace cameras.However,growing such crystals is a challenging task in the field of crystal growth.Heat transfer,flow,and phase change processes of 3,7,and 20 inch(1 inch=2.54 cm)CaF_(2)crystals at different growth stages on the vertical Bridgman growth were conducted by numerical simulation.The results show that as the crystal size increases,the melt flow strength and the area of heat dissipation on the crucible wall increase,resulting in problems such as local depression of the melt-crystal interface,increase in the radial temperature difference,reversal of the temperature difference between the crystal edge and center,and decrease in the axial temperature gradient near the melt-crystal interface.Furthermore,this article discusses optimization strategies for growth rate and power of heater in the growth of large-size CaF_(2)crystals.
作者
施宇峰
王鹏飞
穆宏赫
苏良碧
SHI Yufeng;WANG Pengfei;MU Honghe;SU Liangbi(Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 201899,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《人工晶体学报》
CAS
北大核心
2024年第6期973-981,共9页
Journal of Synthetic Crystals
基金
国家重点研发计划(2021YFE0104800)
国家自然科学基金(61925508)
上海市科委项目(23511102700,23YF1413400)
中国科学院稳定支持基础研究领域青年团队计划(YSBR-024)。
关键词
CaF_(2)晶体
坩埚下降法
尺寸效应
数值模拟
固液界面
温度梯度
CaF_(2) crystal
vertical Bridgman method
size effect
numerical simulation
melt-crystal interface
temperature gradient
