We have studied the energy band diagram for the Si surface and SiO 2 /Si system by using ultraviolet photoelectron spectroscopy (UPS) measurements. In the UPS measurements, monochromatized vacuum ultraviolet with variable incident photon energies below 10.50 eV was used in order to increase the detection limit of the depth from the surface and to understand the electronic states not only at the surface but also in the region near the interface of the stacked structure. From the incident photon energy dependence of the UPS spectral width, the energy level of the valence band top of the H-terminated Si surface and the electrical potential change in the SiO 2 /Si structure has been evaluated. Also, the vacuum work function value of the hetero-epitaxial Ag(111) surface has been investigated to check this measurement technique.

中文翻译：

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可变入射光子能量在真空紫外线下通过UPS分析评估的SiO 2 / Si系统能带图

我们已经通过使用紫外光电子能谱（UPS）测量研究了Si表面和SiO 2 / Si系统的能带图。在UPS测量中，使用可变入射光子能量低于10.50 eV的单色真空紫外光，以增加对表面深度的检测极限，不仅了解表面的电子状态，而且了解界面附近的电子状态的堆叠结构。根据UPS光谱宽度的入射光子能量依赖性，评估了H末端Si表面的价带顶部的能级和SiO 2 / Si结构中的电势变化。另外，还研究了异质外延Ag（111）表面的真空功函数值，以检验该测量技术。