Development of x-ray standing waves for visualizing an atomic-scale interface of electronic materials and devices

我们开发了一种x射线光学系统，包括一个或两个Si（004）通道切割晶体，用于稳定弧秒角发散的反馈控制系统，折射微米透镜和限制狭缝。当入射12.4 keV的x射线光子时，垂直角散度为1.3弧秒，水平光束尺寸约为2微米。我们研究了在H2SO4溶液中的金单晶表面和在蓝宝石单晶上外延生长的薄膜和纳米线。观察了衍射强度和发射曲线的摇摆曲线。这些曲线看起来像一个几乎完美晶体的动态x射线衍射曲线。在金和蓝宝石衬底上发生了动态x射线衍射现象，这是非常令人惊讶和意想不到的。我们的研究结果表明，可以将驻波技术应用于非完美晶体（如金属和氧化物材料）表面系统和薄膜埋藏界面的结构分析。

We developed an x-ray optics including one or two Si (004) channel-cut crystals, a feedback-control system for stabilizing an arc-sec angular divergence, refractive micrometer lenses, and limiting slits. A vertical angular divergence of 1.3 arc sec and a horizontal beam size of about 2 um were evaluated for 12.4 keV incident x-ray photons.We investigated a gold single crystal surface in H2SO4 solution and a thin film and nanowires epitaxially grown on a sapphire single crystal. Rocking curves of diffraction intensities and emission profiles were observed. The curves look like dynamical x-ray diffraction ones for an almost perfect crystal. Dynamical x-ray diffraction phenomena took place in the gold and sapphire substrate, which was quite surprising and unexpected.Our research outcomes indicate that one will apply the standing wave technique to a structural analysis for a surface system and buried interface of thin film on a non perfect crystal like a metal and oxide material.