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In this study X-ray Photoelectron Spectroscopy and Ultraviolet Photoelectron Spectroscopy were combined to investigate the effect of oxygen incorporation on the valence band behaviour of ZrO x . The Auger transitions involving valence bands are found to mimic the self-folded density of state measured using Ultraviolet Photoelectron Spectroscopy. The valence band once constructed in a sub-oxide form, stays at a fixed energy position despite the change in the stoichiometry. This behaviour is found to be useful in setting a reference for X-ray Photoelectron Spectroscopy charge correction. The results of the charged corrected spectra were compared to other methods and found to be in great agreement. Finally, a correlation between the core-level binding energy and the structural property of ZrO x is given.

The surfaces of polyphenylenesulfone samples with the addition of carbon fibers were studied by X-ray photoelectron and Auger-electron spectroscopy. The state of carbon atoms on the surface, the electronic structure, and the distribution of carbon fibers in the surface region as a function of the concentration of the additive were studied. It is shown that with 10 mass. % carbon fiber addition, the transformation of peaks is mainly associated with an increase in the number of carboxyl groups in the matrix, while with a carbon content exceeding 10 mass. %, the increasing role of differential vertical charging becomes the dominant factor. A further increase in the carbon fiber concentration leads to an increase in the conductivity of the bulk part and, consequently, to a decrease in the charge layer without carbon fiber, and therefore, to a decrease in the broadening effect of the C 1s carbon peak.

Ultra-nanocrystalline diamond films were prepared by a microwave plasma-enhanced chemical vapor deposition reactor using CH4/H2 gas mixture with a power as low as 650 W. The effects of CH4 concentration on nanostructure of the films and gas-phase species in plasma were investigated. The CH4 concentrations of 1.5%, 3.0%, 3.5%, and 4.0% were used and balanced with H2 to a total flow rate of 200 sccm. Morphology and composition of the films were characterized by SEM, Raman spectroscopy and Auger spectroscopy. The gas-phase species and electron density in the plasma were explored by optical emission spectroscopy and plasma-impedance measurement. The increasing CH4 concentration from 1.5% to 4.0% increased C2Hx species and decreased electron density. Phase of the film transform from nano- into ultranano- diamond phase but the growth rate revealingly decreased from 300 to 210 nm/h. Raman spectra indicate the higher CH4 concentration promted phase of the film transiton from NCD to UNCD. While Auger spectra revealed that UNCD film deposited with 4.0%CH4 was composed of 90.52% diamond phase but only 9.48% of graphite phase. The relation between phase transformation of the films and growth mechnism controlled by gas-phase species in the plasma will be dissused.

Using a complex of secondary and photoelectron spectroscopy methods, the effects of the implantation of In+ ions with an energy of E0 = 1 keV at different doses and subsequent annealing on the composition, electronic, and crystal structure of the GaP(111) surface were studied. It is shown that in the dose range D ≈ 5 × 1014–5 × 1015 cm−2 after annealing, nanocrystalline phases Ga0.6In0.4P are formed with surface dimensions d ≈ 10–30 nm, and at D ≥ 6 × 1016 cm−2 nanofilm–Ga0.6In0.4P with a thickness of 30–35 nm. It has been found that the band gap of nanophases (Eg ≈ 2–2.3 eV) is much larger than Eg of the film (~1.85 eV). For the first time, information was obtained on the density of state of electrons in the valence band of nanophases and nanofilm GaInP.

Effects of Ba + -ion implantation into silicate glass and its after annealing on the composition, density of electronic states, and parameters of the energy bands are investigated by Auger electron, ultraviolet photoelectron, and light-absorption spectroscopic techniques. It is shown that nonstoichiometric oxides of Si, Pb, and Ba, as well as unbound atoms of the same elements, are formed in the ion implanted layer after ion implantation. As a result, there is a significant change in the electronic structure of silicate glass, in particular, the band gap decreases by ∼2 eV. After annealing at T = 1000 K, unbound Si, Pb, and Ba atoms disappear in the ion implanted layer (within the limits of sensitivity of an Auger-electron spectrometer) and stoichiometric oxides such as SiO 2 , PbO, and BaO are formed.

In this work, the surface of N18 alloy is modified with argon ions in a pulse-periodic mode. In situ electron spectroscopy methods are used to study changes in the chemical composition and local atomic structure caused by ion action on the surface. The chemical composition is determined by Auger electron spectroscopy using argon-ion profiling. Analysis of the local atomic structure is carried out by the method of spectroscopy of extended thin structures of electron energy losses. The excitation spectra of the M 2,3 edge of iron and the K edge of oxygen are obtained in the geometry of backscattering from the surface. A variation in the energy of the incident electron beam makes it possible to obtain a signal from the excitation of oxygen and iron atoms from the same depth. The analysis of experimental data is carried out by the method of solving the inverse problem for finding pair correlation functions using regularization according to Tikhonov. The study of the local atomic structure is carried out at profiling depths of 5, 25, and 50 nm. It is shown that the ion-modified layer within the projective range of argon ions consists mainly of iron oxides. At a profiling depth of 50 nm, the parameters of the local environment of Fe atoms are close to those of unoxidized iron. Nickel as a result of surface diffusion is found at a depth of more than 50 nm.

We use extremely intense, ultrashort soft X-Ray pulses generated by the LCLS X-Ray Free Electron Laser to investigate the production of molecular double core-hole states by sequential two-photon X-Ray absorption. The effect of critical LCLS parameters such as the number of photons per pulse, the pulse duration, and the focal spot size on the photoelectron and Auger spectra is modeled in detail and the results of these simulations are used as an aid in the interpretation of the experimental spectra obtained. The emphasis is on double core-hole formation in small polyatomic molecules such as CO2.

Dependences of the electric conductivity of a contact and wear intensity of metal materials on the electric current density in sliding friction are obtained. It is established that alloying of the material basis leads to faster damage of the friction surface. The presence of about 40 аt.% oxygen in the surface layer is detected by the Auger spectrometry method. It is demonstrated by the x-ray diffraction method that FeO formed in the surface layer leads to an increase in the electric conductivity of the contact.

The nature of stability of aluminum-magnesium materials in aqueous media has been discovered by using the Auger and atomic absorption spectroscopy. It was established that the composition of protective film formed on the aluminum-magnesium alloy in sea water, along with aluminum and oxygen, included also calcium, magnesium, and carbon. Under the scale-free conditions aluminum was not practically detected in external layers of the film consisting of oxides of calcium and magnesium compounds. Magnesium generally passes into solution during the corrosion process, while aluminum remains in the oxide film. The thickness of protective film was also measured. Data obtained during the spectral studies were in good agreement with the results of electrochemical measurements under the same conditions.

The work investigates an increase of the density of free charge carriers in the sub-surface region of p-GaN by adding p-type dopants into the Ni-O layer of an Au/Ni-O metallization structure. We have examined electrical properties and concentration depth profiles of contact structures Au/Ni-Mg-O/p-GaN and Au/Ni-Zn-O/p-GaN, thus with magnesium and zinc as p-type dopants. The metallization layers were deposited on p-GaN by DC reactive magnetron sputtering in an atmosphere with a low concentration of oxygen (0.2 at%). The contacts were annealed in N2 . We have found that the structures containing magnesium or zinc exhibit lower values of contact resistivity in comparison with otherwise identical contacts without Mg or Zn dopants. In our opinion, the lower values of contact resistivity of the structures containing of Mg or Zn are caused by an increased density of holes in the sub-surface region of p-GaN due to diffusion of Mg or Zn from the deposited doped contact layers.