【摘要】 用温度梯度法（ Ｔｅｍｐｅｒａｔｕｒｅ Ｇｒａｄｉｅｎｔ Ｔｅｃｈｎｉｑｕｅ ，简称温梯法或 Ｔ Ｇ Ｔ 法） ，定向籽晶［０００１］ 方向，生长出１１０ｍｍ ×８０ｍ ｍ Ａｌ２ Ｏ３ 单晶，晶体完整、透明。采用硼酸钠玻璃液作为 Ａｌ２ Ｏ３ 晶体的化学抛光和化学腐蚀剂，观察了晶体不同部位处（０００１） 、（１１２０） 晶片的化学腐蚀形貌相，（０００１） 切片的位错腐蚀坑呈三角形，位错密度为２ ×１０３ ～３ ×１０３／ｃｍ２ ；（１１２０） 切片位错腐蚀坑呈菱形，位错密度为７×１０３ ～８ ×１０３／ｃｍ２ ；而且等径生长部位的完整性比放肩处高。利用同步辐射 Ｘ 射线白光衍射实验分析了（０００１） 晶片的（２０２１） ，（１１０１） 和（０２２１） 衍射面内的位错组态。确定了两组位错线的 Ｂｕｒｇｅｒｓ矢量，温梯法生长的 Ａｌ２ Ｏ３ 晶体中的位错主要是刃型位错。更多还原

【Abstract】 The large size Al 2O 3 crystal of 110mm in diameter and 80mm in high has been grown using a directional seed crystal in [0001]direction by the Temperature gradient technique (TGT) in our laboratory.The as grown Al 2O 3 crystal is integraty and transparent.The B 2O 3 Na 2O glass system was adopted as the chemical polisher and chemical corrodent.The etch pits of the (0001) and (1120) slices cut from the various parts of as grown crystal were observed under the Leitz microscope.The dislocation etching pits of (0001) slice are triangular with the lower dislocation density of 2×10 3—3×10 3cm -2 ,while the dislocation etching pits of (1120) slices are quadrilateral with the higher dislocation density of 7×10 3—8×10 3cm -2 .The dislocation configurations and diffraction contrasts in some diffraction planes of (0001)slice have been studied by the synchrotron radiation X ray diffraction topography.The Burgers vectors of two array dislocations are determined,and the dislocations in Al 2O 3 crystal grown by TGT are edge type dislocation.更多还原