大尺寸高质量γ-LiAlO2晶体的制备研究

采用提拉法快速（6mm／h）生长了透明、φ45mm×50mm完整的铝酸锂晶体，但晶体中下部出现了一个树状、乳白色的核芯．分别从透明和乳白色核芯部位取样，研磨作粉末X射线衍射测试，发现两个样品所有的衍射峰均可以用γ-LiAlO2指标化．双晶摇摆曲线显示晶体透明和乳白色部位的半高宽分别为116．9arcsec和132．0axcsec，结晶质量较差．通过三步气相传输平衡法（简称VTE）处理后，透明部位半高宽值（FWHM）降至44．2arcsec，乳白色部位FWHM值降至53．3arcsec．结合快速生长和VTE

Transparent gamma-LiAlO2 crystal was quickly grown by Cz technique. It was 45mm in dimension and 50mm long. However, it appeared a dendriform, milky core. The samples taken from transparent part and milky one, were ground for examining X-ray diffraction. The diffraction peaks of samples can be indexed by gamma-LiAlO2. The FWHM values shown by X-ray rocking curves were 116.9 and 132.0arcsec, respectively. The corresponding FWHM value was dropped to 44.2 and 53.3arcsec through three VTE processes. Through linking fast growth with Vapor Transport Equilibration (VTE) technique, high quality LAO slice with the dimension of Phi 40mmx40mm was obtained.