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ＬｉＡｌＯ２和ＬｉＧａＯ２是目前找到的和ＧａＮ晶格失配率最小的两种晶体，其失配率分别为１．４％和０．２％．本研究分别利用温梯法和提拉法成功地生长出了ＬｉＡｌＯ２和ＬｉＧａＯ２单晶．通过化学侵蚀、光学显微镜、透射电子显微镜和Ｘ射线衍射貌相术对两种晶体中的缺陷特征进行了分析，研究了晶体特性、生长方法和缺陷形成的关系．用温梯法生长的ＬｉＡｌＯ２晶体质量良好，晶体中无气泡、包裹物．ＬｉＡｌＯ２晶体中的位错密度约为３．８×１０４—６．０×１０４／ｃｍ２，晶体中的主要缺陷为亚晶界或镶嵌，可能是由于温度场不稳定及生长速率太快造成的．而用普通的提拉法生长的ＬｉＧａＯ２晶体由于原料按非化学计量比挥发，致使组分偏离，容易产生γ－Ｇａ２Ｏ３包裹物，包裹物和位错的形成具有一定的相互促进作用，往往形成平行于（００１）面的亚晶界，通过调整原料配比及生长工艺参数可克服上述问题．测得ＬｉＧａＯ２晶体的位错密度为７．０×１０５—９．２×１０５／ｃｍ２．温梯法在生长有熔体组分挥发的晶体方面远优于提拉法
LiAlO2 and LiGaO2 are the two crystals found to have the least lattice mismatch rate with the mismatch rates of 1.4% and 0.2% respectively. In this study, LiAlO2 and LiGaO2 single crystals were successfully grown by the temperature gradient method and the Czochralski method respectively. The characteristics of defects in the two kinds of crystals were analyzed by chemical attack, optical microscope, transmission electron microscope and X-ray diffraction. The relationship between the crystal properties, growth method and defect formation was studied. The crystal of LiAlO2 grown by the warm step method is of good quality, no bubbles and inclusions in the crystal. The dislocation density in LiAlO2 crystals is about 3.8 × 104-6.0 × 104 / cm2. The main defects in the crystals are subgrain boundaries or inlays, which may be due to the unstable temperature field and too fast growth rate. However, due to the non-stoichiometric ratio of the raw materials, the LiGaO2 crystals grown by the conventional Czochralski method cause the components to deviate and easily produce γ-Ga2O3 inclusions. The formation of the inclusions and dislocations has a certain mutual promotion effect and tends to form parallel In the (001) plane of the subgrain boundaries, by adjusting the raw material ratio and growth process parameters can overcome the above problems. Dislocation density of the LiGaO2 crystal was measured to be 7.0 × 10 5 -9.2 × 10 5 / cm 2. The temperature-gradient method is far superior to the Czochralski method in growing volatile crystals of the melt component