Zhang Liyao, Wu Mingjian, Chen Xiren, Wu Xiaoyan, Spiecker Erdmann, Song Yuxin, Pan Wenwu, Li Yaoyao, Yue Li, Shao Jun, Wang Shumin
State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, CAS, 865 Changning Road, Shanghai, 200050, China.
Institute of Micro- and Nanostructure Research & Center for Nanoanalysis and Electron Microscopy (CENEM), Department of Materials Science, Universität Erlangen-Nürnberg, Cauerstraße 6, D-91058, Erlangen, Germany.
Sci Rep. 2017 Sep 25;7(1):12278. doi: 10.1038/s41598-017-12075-2.
The nanoscale distribution of Bi in InPBi is determined by atom probe tomography and transmission electron microscopy. The distribution of Bi atoms is not uniform both along the growth direction and within the film plane. A statistically high Bi-content region is observed at the bottom of the InPBi layer close to the InPBi/InP interface. Bi-rich V-shaped walls on the (-111) and (1-11) planes close to the InPBi/InP interface and quasi-periodic Bi-rich nanowalls in the (1-10) plane with a periodicity of about 100 nm are observed. A growth model is proposed to explain the formation of these unique Bi-related nanoscale features. These features can significantly affect the deep levels of the InPBi epilayer. The regions in the InPBi layer with or without these Bi-related nanostructures exhibit different optical properties.
通过原子探针断层扫描和透射电子显微镜确定了InPBi中Bi的纳米级分布。Bi原子的分布在生长方向和薄膜平面内均不均匀。在靠近InPBi/InP界面的InPBi层底部观察到一个统计上Bi含量较高的区域。在靠近InPBi/InP界面的(-111)和(1-11)平面上观察到富Bi的V形壁,在(1-10)平面上观察到周期约为100 nm的准周期性富Bi纳米壁。提出了一个生长模型来解释这些独特的与Bi相关的纳米级特征的形成。这些特征会显著影响InPBi外延层的深能级。InPBi层中具有或不具有这些与Bi相关的纳米结构的区域表现出不同的光学性质。