Depth-resolved analysis of lattice distortions in high-Ge-content SiGe/compositionally graded SiGe films using nanobeam x-ray diffraction
Depth-resolved analysis of lattice distortions in high-Ge-content SiGe/compositionally graded SiGe films using nanobeam x-ray diffraction
复制标题
使用纳米束 X 射线衍射对高 Ge 含量 SiGe/成分梯度 SiGe 薄膜中的晶格畸变进行深度分辨分析
DOI：
10.1088/1361-6641/aae6d9
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发表时间：
2018
影响因子：
1.9
通讯作者：
Sakai Akira
中科院分区：
文献类型：
--
作者：
Shida Kazuki;Takeuchi Shotaro;Tohei Tetsuya;Imai Yasuhiko;Kimura Shigeru;Schulze Andreas;Caymax Matty;Sakai Akira
研究了高Ge含量的恒组分Si0.3Ge0.7（CC-SG）/组分渐变SiGe应变弛豫缓冲层（gradedSRB）/Si（001）叠层结构中晶格畸变的三维结构，包括晶格面倾斜和扭曲.同步辐射纳米束X射线衍射的位置相关的ω-2θ-φ映射（或三维倒易空间映射）揭示了样品表面10× 10 μm范围内的局部倾斜和扭曲的面内分布。深度分辨的晶体信息的基础上提取分析的结构特征的梯度SRB层。结果，一系列的层析地图，显示了三维分布的倾斜和扭曲周围的CC-SG/梯度SRB界面。层析分析表明，分级硫酸盐还原岩中的晶面取向在特定深度和特定间隔处发生突然变化。用透射电子显微镜观察到的失配位错分布是不均匀的，但集中在一个特定的深度，这占晶格平面倾斜和扭曲的突变。我们的层析结果清楚地验证了SiGe堆叠结构中的位错形态，这表明这种分析方法可以成为一种强有力的工具，用于定量和非破坏性地阐明具有高空间分辨率的三维晶格结构。
We have investigated the three-dimensional configuration of lattice distortions, including lattice plane tilt and twist, in a high-Ge-content constant-composition Si 0.3 Ge 0.7 (CC-SG)/compositionally graded SiGe strain-relaxed buffer (graded SRB)/Si (001) stacked structure. Position-dependent ω–2θ–φ mapping (or three-dimensional reciprocal space mapping) by synchrotron-based nanobeam x-ray diffraction revealed the in-plane distributions of both local tilt and twist within an area of 10× 10 μm on the sample surface. Depth-resolved crystal information was extracted analytically on the basis of structural features in the graded SRB layer. As a result, a series of tomographic maps that show the three-dimensional distributions of tilt and twist around the CC-SG/graded SRB interface were obtained. Tomographic analysis indicates that the orientation of lattice planes in the graded SRB abruptly changes at a specific depth and at a specific interval. The misfit dislocation distribution observed using transmission electron microscopy is not homogeneous but concentrated at a specific depth, which accounts for the abrupt changes of lattice plane tilt and twist. Our tomographic results clearly verify the dislocation morphology in the SiGe stacked structure, which demonstrates that this analysis method can be a powerful tool for quantitative and non-destructive elucidation of a three-dimensional lattice structure with high spatial resolution.