Defect formation in the solid phase epitaxial growth of GaAs films on Si (001) substrate
Defect formation in the solid phase epitaxial growth of GaAs films on Si (001) substrate
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Si(001)衬底上固相外延生长GaAs薄膜的缺陷形成
DOI：
10.1063/1.347756
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发表时间：
1991
影响因子：
3.2
通讯作者：
T. Nishinaga
中科院分区：
文献类型：
--
作者：
Kurn Cho;W. Choo;Jung;Suntak Park;T. Nishinaga
通过高分辨率透射电子显微镜研究了 (001) Si 衬底上向 [110] 方向倾斜 ∼3° 的 GaAs 薄膜的缺陷结构。采用改进的两步工艺，通过分子束外延 (MBE) 在 Si (001) 衬底上生长 GaAs 薄膜，其中首先生长非晶 GaAs 缓冲层。高分辨率电子显微照片显示，堆垛层错（和/或微孪晶）优先在倾斜的富含台阶的表面上形成，而失配位错优先在平坦的表面上形成。然而，两个截面上的缺陷密度差异很小。在观察到的 90° 边缘和 60° 失配位错之间，无论衬底倾斜如何，后者的密度都较高。这种现象可以通过现有的两步 MBE 技术和传统的两步 MBE 技术之间初始成核岛分布的差异来解释。
The defect structures of GaAs film on (001) Si substrate tilted ∼3° towards the [110] direction were investigated by the high‐resolution transmission electron microscopy. GaAs films were grown by the molecular beam epitaxy (MBE) on the Si (001) substrate by a modified two‐step process, in which amorphous GaAs buffer layers were grown first. High‐resolution electron micrographs show that stacking faults (and/or microtwins) are preferentially formed on the tilted step‐rich surface, whereas misfit dislocations are preferentially formed on the flat surface. However, the difference in the defect density on the two cross sections is small. Between the observed 90° edge and 60° misfit dislocations the density of the latter is higher irrespective of the substrate tilt. This occurrence is explained by the difference in distribution of initial nucleating islands between the present and the conventional two‐step MBE techniques.