Photoelectron Spectroscopy Metrology Of The Oxidation And Hydrogenation Of Ge Surface

In recent years, the semiconductor Ge has been used extensively in industral and our life. As the size of the nano-chips and nano-devices are reduced gradually,nanometer semiconductor Ge exhibited a variety of novel physical properties different from bulk materials. So, the exploration of the physical mechanisms of these physical characteristics has very scientific and practical value. However, the process that use classical theoretical model to discuss these characteristics encountered some problems difficult to breakthrough. Therefore, the application of a new theoretical model is very necessary, which not only can overcome the obstacle encountered by the classical theory, but also explain the physical properties of these novel essentially.In this paper, we showed a combination of density functional theory(DFT)calculations, X-ray photoelectron spectroscopy(XPS), zone-resolved X-ray photoelectron spectroscopy(ZPS), tight-binding approach, the bond order-length-strength(BOLS) and non-bonding electron polarization(NEP)correlation notion to study the physical mechanism of the core level shift of Ge surface and impurities surface. Specific content and results are as follows:(i) It turns out that the 3d energy level of an isolated Ge atom amounts at27.579 eV, which shifts deeper with respect to the 28.960 eV of upon bulk formation.The 3d electrons of the under-coordinated Ge(100) and Ge(111) atoms undergo quantum entrapment because of the surface chemical bond contraction. Meanwhile,we predict the quantitative information of local lattice strain, the atomic cohesive energy and so on.(ii) Using DFT calculation, we got quantitative information of the d-orbital local DOS of the Ge(100),(100)-H and the stepped Ge(210) skins, and then the bond contraction factor of Ge(210) skins. Meanwhile,H adsorption results in the local polarization that raises the 3d electrons binding energy(BE) shifts from 1.381 eV to0.952 eV.(iii) Using the combination of BOLS-TB notation and the ZPS technique, we analyze the 3d core level shift of the passivation and adsorption of Ge surface, and obtain O2, H2O2, H2 O, HF passivation of Ge(100) skin and Au adsorption results in quantum entrapment by different amounts. Meanwhile, ZPS obtained impurity induced Ge 3d energy level interface BE.Theoretical analysis is consistent with experiments, which confirms that the BOLS-NEP-TB theory is available in interpret the energy level shift of illcoordinated systems. Simultaneously, it also provides guidance for us to further explore other unusual characteristics of nanomaterials.