Sankowska Iwona, Jasik Agata, Czuba Krzysztof, Ratajczak Jacek, Kozłowski Paweł, Wzorek Marek
Łukasiewicz Research Network-Institute of Microelectronics and Photonics, al. Lotników 32/46, 02-668 Warsaw, Poland.
Materials (Basel). 2021 Aug 30;14(17):4940. doi: 10.3390/ma14174940.
In this paper, the study of defects in InAs/GaSb type-II superlattices using high-resolution an x-ray diffraction method as well as scanning (SEM) and transmission (TEM) electron microscopy is presented. The investigated superlattices had 200 (#SL200), 300 (#SL300), and 400 (#SL400) periods and were grown using molecular beam epitaxy. The growth conditions differed only in growth temperature, which was 370 °C for #SL400 and #SL200, and 390 °C for #SL300. A wings-like diffuse scattering was observed in reciprocal space maps of symmetrical (004) GaSb reflection. The micrometer-sized defect conglomerates comprised of stacking faults, and linear dislocations were revealed by the analysis of diffuse scattering intensity in combination with SEM and TEM imaging. The following defect-related parameters were obtained: (1) integrated diffuse scattering intensity of 0.1480 for #SL400, 0.1208 for #SL300, and 0.0882 for #SL200; (2) defect size: (2.5-3) μm × (2.5-3) μm -#SL400 and #SL200, (3.2-3.4) μm × (3.7-3.9) μm -#SL300; (3) defect diameter: ~1.84 μm -#SL400, ~2.45 μm -#SL300 and ~2.01 μm -#SL200; (4) defect density: 1.42 × 10 cm -#SL400, 1.01 × 10 cm -#SL300, 0.51 × 10 cm -#SL200; (5) diameter of stacking faults: 0.14 μm and 0.13 μm for #SL400 and #SL200, 0.30 μm for #SL300.
本文介绍了利用高分辨率X射线衍射方法以及扫描电子显微镜（SEM）和透射电子显微镜（TEM）对InAs/GaSb II型超晶格中的缺陷进行的研究。所研究的超晶格具有200（#SL200）、300（#SL300）和400（#SL400）个周期，采用分子束外延生长。生长条件仅在生长温度上有所不同，#SL400和#SL200的生长温度为370°C，#SL300的生长温度为390°C。在对称（004）GaSb反射的倒易空间图中观察到了翅膀状的漫散射。通过结合SEM和TEM成像对漫散射强度进行分析，揭示了由堆垛层错和线性位错组成的微米级缺陷团聚体。获得了以下与缺陷相关的参数：（1）#SL400的积分漫散射强度为0.1480，#SL300为0.1208，#SL200为0.0882；（2）缺陷尺寸：#SL400和#SL200为（2.5 - 3）μm×（2.5 - 3）μm，#SL300为（3.2 - 3.4）μm×（3.7 - 3.9）μm；（3）缺陷直径：#SL400约为1.84μm，#SL300约为2.45μm，#SL200约为2.01μm；（4）缺陷密度：#SL400为1.42×10/cm，#SL300为1.01×10/cm，#SL200为0.51×10/cm；（5）#SL400和#SL200的堆垛层错直径为0.14μm和0.13μm，#SL300为0.30μm。
