【摘要】 研究了温度梯度法生长的γLiAlO2晶体在1100℃不同气氛处理的热稳定性。借助扫描电子显微镜和X射线衍射分析发现:1100℃/10h真空和空气处理后的样品表面分别形成了均匀微孔状和岛状LiAl5O8多晶;而富Li气氛处理后样品表面仍然光滑且仍为LiAlO2。用Leitz大视场显微镜观察重新抛光后样品内部宏观缺陷,发现空气和真空处理后样品缺陷增多,分别为岛状和条纹状缺陷;而富Li气氛处理后样品中缺陷明显减少。对比不同气氛处理的4块样品吸收光谱,确认了真空和空气处理产生的196nm吸收峰可能是Li空位吸收峰。更多还原

【Abstract】 The thermal stability of γLiAlO₂ crystal grown by temperature gradient technique at 1 100 ℃ in different ambient were investigated. The crystals obtained were examined by scanning electron microscope （SEM） and X-ray diffraction （XRD）. The results show that the islandish, micro-holes LiAl₅O₈ phase appear on the surface when they are annealed in air and vacuum at 1 100 ℃ for 10 h. The inner defects were observed by Leitz microscope. The punctual pits, disordered stripes are seen in the samples after annealed in air and vacuum. However the surface is almost unchanged for samples treated in Li-rich ambient and the inner defects disappear. Study on the absorption spectrum of the samples, it can be determined that the 196 nm absorption peak after annealed in air and vacuum is probably caused by lithium vacancies.更多还原