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在超高真空系统中,超薄层 Pt淀积膜原位蒸发在原子清洁的 Si(111)表面上形成 Pt/Si界面.利用光电子谱技术(XPS和UPS)研究了Pt/Si 界面的化学性质.测量了Si2p和Pt 4f芯能级和价带电子态,并着重研究这些芯能级及电子态在低覆盖度时的变化.由 Si(2p)峰的强度随 Pt 覆盖度的变化可以清楚证明:在 300 K下淀积亚单原子层至数个单原子层 Pt的 Pt/Si(111)界面发生强烈混合作用,其原子组伤是缓变的.由于Si原子周围的 Pt原子数不断增加,所以 Pt 4f芯能级化学位移随 Pt原子覆盖度的增加而逐步减小,而Si 2p芯能级化学位移则逐步增大.同时,Pt 4f峰的线形也产生明显变化,对称性增加;Si 2p峰的线形则对称性降低.淀积亚单原子层至数单原子层Pt的UPS谱,主要显示两个峰:-4.2eV(A峰),-6.0eV(B峰).A峰随着覆盖度的增加移向费米能边,而B峰则保持不变.这说明Ptd-Sip键合不受周围Pt原子增加的影响.利用Pt/Si界面Pt原子向Si原子的间隙扩散模型讨论了所观察到的结果.
In the ultra-high vacuum system, the ultra-thin layer of Pt deposited film was evaporated in situ to form the Pt / Si interface on the atom-clean Si (111) surface.The chemical properties of Pt / Si interface were studied by using photoelectron spectroscopy (XPS and UPS) Properties The energy levels and valence band states of Si2p and Pt4f were measured and the changes of their energy levels and electronic states at low coverage were studied. The change of Si (2p) peak intensity with Pt coverage It is clearly proved that the atomic group damage is gradual due to the strong mixing of the Pt / Si (111) interface deposited at 300 K on the Pt / Si (111) interface from the monatomic layer to the Pt layer. Due to the number of Pt atoms The chemical shifts of Pt 4f core gradually decrease with the increase of Pt atomic coverage, while the chemical shifts of Si 2p core gradually increase.Also, the linearity of Pt 4f peak also changes obviously, the symmetry And the symmetry of the Si 2p peak decreases linearly.The UPS spectrum of deposition of Pt to the monatomic layer Pt mainly shows two peaks: -4.2eV (A peak) and -6.0eV (B peak). The peak of A shifts to the Fermi edge while the peak of B stays the same as the coverage increases, indicating that Ptd-Sip bonding is not affected by the increase of surrounding Pt atoms. Pt / Si interface Pt atoms discusses the results observed clearance Si atom diffusion model.