Investigation on Improvement in the Ultrasoft X-ray Excited Photoelectron Spectroscopy

在本文的超软x射线激发光电子能谱研究中，试图实现能量分辨率的提高、x射线强度的提高、利用衍射光栅产生单色x射线和电源的高稳定性，并澄清了以下几点：1)测量的Si2p光电子能谱中包含的背景信号强度非常大，这是由于高能电子入射到样品表面造成的。为了消除这些高能电子，偏转板的设计需要优化。(2)在本研究中，入射角度为15°的衍射光栅上的x射线衍射强度较弱。为了增加这种强度，应该优化入射角。(3)由于ZrMzeta辐射的低透过率，ZrMzeta线的频宽受污染的影响比较敏感。利用ZrMzera激发光电子能谱的高表面灵敏度，可以研究氧化硅表面、超薄氧化硅膜的化学结构。结果表明：1)在干氩气或干氮气中退火，在热氧化物表面形成亚氧化硅。(2)室温下在去离子水中形成的硅天然氧化物的化学结构受晶体平面上硅原子密度的影响较小。(3)（100）表面硅原生氧化物的生成速率大于（110）和（111）表面。(4)湿法化学处理形成的硅原生氧化物中Si^<3+>的分布取决于化学处理方法。Si^<3+>可以与Si- h键相关联。

In the present investigation on ultrasoft X-ray excited photoelectron spectroscopy, the increase in energy resolution, the increase in X-ray intensity, the production of monochromatic X-ray using diffraction grating and the high stability of power supply were tried to realize and the following points were clarified: 1) The intensities of background signals included in Si2p photoelectron spectra measured are extremely large, because of high energy-electrons incident on the sample surface. The design of deflector for the elimination of these high energy-electrons should be optimized., 2) In the present study, the X-ray incident on diffraction grating with incident angle of 15 degrees results in weak diffracted intensity. In order to increase this intensity, the incident angle should be optimized., 3) The FWHM of ZrMzeta line is sensitively affected by the contamination because of low transmittance of ZrMzeta radiation.Using high surface sensitivity of ZrMzera excited photoelectron spectroscopy, the chemical structures of silicon oxide surface, those of ultrathin silicon oxide films could be investigated. Results can be summarized as follows: 1) The silicon suboxides are formed on the surface of thermal oxides by annealing in dry argon or dry nitrogen., 2) The chemical structures of silicon native oxides formed in deionized water at room temperature are weakly affected by the density of silicon atoms in the crystallographic plane., 3) The formation rate of silicon native oxides on (100) surface is larger than those on (110) and (111) surfaces., 4) The distribution of Si^<3+> in silicon native oxides formed during wet chemical treatments depends on the method of chemical treatments. This Si^<3+> can be correlated with Si-H bond.