Growth of Large Rutile Single Crystal by Heater-Inserted Floating Zone Method

插入加热器浮区法生长大金红石单晶

• 批准号: 08455401
• 负责人: KODAIRA Kohei
• 金额: $ 4.93万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08455401/
• 关键词: Rutile; Polarizing Material; Single Crystal; Floating Zone Method; Heater-Inserted Floating Zone Method; ルチル単結晶; 引き下げ法

Rutile single crystals have attracted much attention for their applications as polarizar. The single crystal have success fully grown by the floating zone (FZ) method, which is difficult to grow large size crystals because the molten zone is kept only by surface tension of the melt. In this study, we have grown large rutile single crystals by the heater-inserted floating zone (heater-inserted FZ) method, in which the melts were supported at the bottom of the iridium crucible and growing crystals The size of a hole at the crucible center should be 2mm in diameter to keep continuous feeding of the melt to the growth region. The use of heat insulating materials made of porous zirconia was effective to melt the rutile. A heat-shielding plate below the crucible was also effective to shallow temperature gradient.Continuous feeding of raw materials were possible to grow for long time by using granular TiO_n. Rutile single crystals with about 25mm in diameter were successfully grown by the heater-inserted FZ method. It will be possible to grow rutile single crystals having larger diameters by a larger crucible.

金红石单晶因其在偏振光方面的应用而备受关注。用浮区法生长单晶获得了成功，而浮区法仅靠熔体的表面张力维持熔区，难以生长出大尺寸的单晶。在本研究中，我们采用插入加热器浮动区（加热器-插入FZ）的方法生长了较大的金红石单晶，其中熔体被支撑在铱坩埚的底部，生长晶体在坩埚中心的孔的直径为2mm，以保持熔体连续馈送到生长区域。采用多孔氧化锆保温材料对金红石有较好的熔融效果。在坩埚下方加隔热板，对温度梯度较浅也有较好的抑制作用。采用颗粒状TiO_n可使原料长时间连续进料生长。采用热插拔法成功地生长出了直径约为25mm的金红石单晶。用更大的坩埚可以生长出直径更大的金红石单晶。