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本文从结晶化学角度出发，结合晶体的生长工艺研究了顶部籽晶溶盐法（ＴＳＳＧ）生长ＢａＴｉＯ３晶体中的包裹体形成机理及其对电畴结构的影响。在ｃ轴籽晶生长的晶体中，包裹体主要是沿着籽晶分布在晶体的放肩起始区域里。通过显微观察发现，通常为四方锥形和四方台形两种几何形状，并以四方锥形为多见。四方锥形的锥顶方向与提拉方向相反，指向溶液；锥面与｛１１１｝面族平行，晶体中四方锥形包裹体的结晶形貌和方位完全相同，具有负晶结构的特性。四方台形包裹是未发育完整的四方锥包裹体。通过定向发现，ＢａＴｉＯ３晶体中负晶的四个锥面与晶体中｛１１１｝面族的四个锥面平行是一种内向生长机理。结合晶体生长的物理化学条件，从包裹体的分布和结晶方位来分析，提出该种负晶体结构包裹体的形成是由于在放肩阶段，肩部面积按指数律增加，热量容易耗散；与此同时，因晶体转动的线速度是由缘及里逐渐减慢，位于籽晶下方的晶体与溶液之间的相对流动减少，导致径向温度梯度由边缘向中央逐渐降低。在ＢａＴｉＯ３晶体放肩生长时容易形成凹的固液界面，易将溶液包裹在晶体的中部。根据负离子配位多面体生长基元的理论模型，被包裹的溶液在冷却过程中是以ＴｉＯ６八面体和Ｂａ２＋（或ＢａＯ１２立方八?
In this paper, the formation mechanism of inclusions in BaTiO3 grown by top-seed-solution-salt method (TSSG) and its effect on the domain structure were investigated from the perspective of crystallinity and crystal growth. In c-axis seed crystal growth, inclusions are mainly distributed along the seed crystal in the starting shoulder area. Through the microscopic observation, it is usually found that there are four geometric shapes, such as tetragonal pyramid and tetragonal pyramid, and the tetragonal pyramid is more common. The direction of the pyramid top of the tetragonal pyramidal cone is opposite to the pulling direction and points to the solution. The pyramidal plane is parallel to the {111} plane family. The tetragonal pyramidal inclusions in the tetragonal crystal have exactly the same crystal morphology and orientation and have the negative crystal structure. Sifang tectonic package is not developed complete tetragonal cone inclusions. It is found by in-orientation that the four conical surfaces of the negative BaTiO3 crystal parallel to the four conical surfaces of the {111} plane in the crystal are an inward growth mechanism. Combined with the physical and chemical conditions of crystal growth, we analyze the distribution of inclusions and crystal orientation, and propose that the formation of such negative crystal structure inclusions is due to the exponential increase of shoulder area and the dissipation of heat due to the release of shoulders. At the same time, the relative linear velocity between the crystal and the solution decreases as the linear velocity of the crystal slows down from the edge and gradually decreases the radial temperature gradient from the edge to the center. In BaTiO3 crystal shoulder is easy to form a concave solid-liquid interface, easy to wrap the solution in the middle of the crystal. According to the theoretical model of anion coordination polyhedron growth primitives, the wrapped solution is based on TiO6 octahedron and Ba2 + (or BaO12 cubic eight?