用x射线形貌研究半绝缘砷化镓单晶胞状结构

通过x射线异常透射形貌（XRT），化学腐蚀显微观察和电子显微技术（TEM）研究了液封直拉（LEC）法生长的半绝缘砷化镓（SI-GaAs）单晶中蜂窝状胞状结构，从晶体生长和冷却过程的热应力、弹性形变引起位错的运动和反应考虑，分析了该结构的形成机理与过程.认为这是由高密度位错（EPD）运动和反应所形成的小角度晶界的集合群. 关键词： SI-GaAs 小角度晶界 胞状结构

Study on the cell structure in semi-insulation gallium arsenide

Defects constructing a netlike cell structure in the 3-inch semi-insulating gallium arsenide (SI-GaAs) single crystal were studied by methods of chemical etching, x-ray anomalous transmission topography (XRT) and transmission electron microscope (TEM). The nature and the formation mechanism of these structures were analyzed. It is assumed that the cell structures are made by the clusters of small angle grain boundary caused by the movement and interaction of high density of dislocations. and the cell wall is the typical small angle grain boundary. The phase difference among the small angle grain boundaries increases with the density of dislocations.