A Study of Surface diffusion of Hydrogen by Hydrogen Microscope

了解氢在固体表面上的反应行为及其影响是十分重要的。许多研究者使用经典方法对固体中的氢扩散进行了研究。然而，由于没有市面上可用的表面氢分析工具，关于固体表面氢扩散的研究很少。因此，表面氢的行为仍有未解决的问题。现在我们利用飞行时间型电子刺激解吸（TOF-ESD）光谱和聚焦电子枪来研究二维氢的分布。扫描型ESD离子显微镜（SESDIM）不仅可以测量固体表面氢和氧的分布，还可以在1000 nm的空间分辨率上进行化学分析。它有望在空间分辨率的区域内研究氢的表面扩散。由于氢在室温左右的固体表面上运动，因此有必要对样品操纵器进行冷却以研究氢的扩散。作为一种工作在低温下的高精度机械手，它的设计和制造都花费了很长时间。在-60℃到100℃之间，铝硅表面的扩散有差异。然而，这还不足以获得实验结果。相反，SESDIM适用于研究高温下固体表面的氧扩散。在本研究中，氢和氧在多孔硅和氮化硅杂化表面的行为。此外，在对SESDIM进行改进的过程中，研制出了一种新的x射线显微镜，该显微镜在低能量电子激发（~ 1 keV）的情况下仍具有100 nm的高空间分辨率。如果将来研制出接近1 keV的x射线能量分析仪，这种x射线显微镜对活体样品有很高的价值。

It is important to know behaviors and effect of surface reaction of hydrogen on solid surfaces. The hydrogen diffusion in solid has been studied by many investigators using classical methods for various materials. However, there are few publications on surface diffusion on solid surface because no commercially available tool for surface hydrogen analysis. Therefore, there are still unsettled problems on surface hydrogen behaviors. Now we use the time-of-flight type electron stimulated desorption (TOF-ESD) spectroscopy and a focused electron gun to study two-dimensional hydrogen distribution. A scanning type ESD ion microscope (SESDIM) measures not only hydrogen distribution but chemical analysis of hydrogen and oxygen on solid surfaces in spatial resolution of 1000 nm. It was expected to study surface diffusion of hydrogen in a region of the spatial resolution. It is necessary to cool the sample manipulator to study hydrogen diffusion because hydrogen moves on solid surface at around room temperatures. As a high precision manipulator which works at low temperatures is not available easy, it took a long time to design and product it. Difference of diffusion has been observed in the case of an aluminum covered silicon surface between-60℃ to 100℃. However, it was not enough to obtain the experimental results In contrast, this SESDIM is suitable to study oxygen diffusion on solid surface at higher temperatures. In this study, hydrogen and oxygen behaviors on a hybrid surfaces of porous silicon and silicon nitride.In addition, in the process on improvement of the SESDIM, a new X-Ray microscope which has a high spatial resolution of 100 nm in spite of low energy electron excitation (〜1 keV). In futeur if an X-Ray energy analyzer near 1 keV is developed, this X-Ray microscope is highly valuable for living body samples.