γ-LiAlO2晶体生长、改性和热学性质研究

采用快速提拉法生长出了透明、完整的γ-LiAlO₂晶体，但是晶体的高熔点和易 挥发性限制了γ-LiAlO₂晶体质量.采用气相传输平衡法（vapor transport equilibra tion technique,VTE）工艺对晶体改性，半高宽（FWHM）值从1169arcsec降至442arcsec，继续升高VTE处理温度至1300℃，FWHM值反而升高至552arcsec.快速提拉法生长出来晶体，100］方向和［001］方向的热膨胀系数分别为172398×10^-6/K，107 664×10^-6/K.经过三步VTE处理后［100］和［001］方向热膨胀系数降至16 6539×10^-6/K和101784×10^-6/K. 关键词： 2')" href="#">γ-LiAlO₂ 气相传输平衡法 热膨胀系数

Study on the growth, modification and thermal properties of γ-LiAlO2 single crystals

Transparent and crack-free γ-LiAlO₂ single crystal was grown by quic k Czochra lski technique. However, high melting point and easy volatilization degraded the quality of the crystal. The fall with at half maximum(FWHM) value dropped from 1169arcsec to 442arcsec when the crystal was modified by vapor transport equ ilibrium(VTE) technique. But when the temperature of VTE was 1300℃, the FWHM va lue increased to 552arcsec. The ［100］-orientation thermal expansion coeffici ent of the as-grown crystal was 176798×10^-6/K, while that alon g the ［0 01］-orientation was 107664×10^-6/K. After three VTE treatments , the cor responding thermal expansion coefficients decreased to 166539×10^{-6/K and 101784×10-6/K, respectively.}