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In this paper, we study the kinetics of potassium adsorption on SrTiO₃(100) surface at room temperature. The study took place in UHV using AES, EELS, LEED, TPD, and WF measurements. Potassium grows in two-dimensional islands with maximum coverage of 3.9 × 10¹⁴ at/cm². During adsorption charge transfer from the K-4s to Ti-3d energy level has been observed. No K–O compound has been measured. After heating at 1050 K most of the adsorbed potassium desorbs and the SrTiO₃(100) (1 × 1) LEED pattern reappears. There is not any indication of potassium intercalation into the substrate, either at room or at elevated temperature.

The surface of materials plays an important role in their technological applications. In the interest to study the stability of materials and their behavior, we irradiate them by the electrons by using the electron spectroscopy such as the Auger electron spectroscopy (AES) and the electron energy loss spectroscopy (EELS). These methods have proved their good sensitivity to study material surfaces. In this paper, we give some results about the effect of the electron beam irradiating the compounds InP, InSb, InPO₄ and In_xGa_1-xAs. The III–V semiconductors InP and InSb seem to be sensitive to the electron irradiation. This breaks the chemical bonds between the element III and V which leads to an oxidation process at the surface. The AES and EELS spectroscopy are also used to characterize the oxide InPO₄ whose thickness is about 10 Å grown on the substrate InP(100). The irradiation of the system InPO₄/InP(100) by the electron beam of 5 keV energy leads to a structural change of the surface, so that there is breaking of chemical bonds between indium and phosphorus (In–P) and formation of new oxide other than InPO₄. In this study we show an important result concerning the effect of the electron beam on the compound In_xGa_1-xAs by varying the parameter x to obtain In_0.2Ga_0.8As and In_0.53Ga_0.47As. It appears that the electron beam affects In_0.2Ga_0.8As too much in comparison with In_0.53Ga_0.47As. In the case of the irradiation of In_0.2Ga_0.8As, there is breaking of chemical bonds between indium and GaAs leading to formation of indium oxide associated to GaAs.

Recently, the development of indium oxide such as In₂O₃ on the III–V semiconductors shows successful technological applications as in the gas sensor field, the emission devices, the biotechnology, etc. The indium oxide In₂O₃ attracted considerable research due to many methods of its synthesis. In our study, we were interested in developing the indium oxide In₂O₃ on the In metal and InSb surfaces by electron beam stimulated oxidation. The formation of In₂O₃ on InSb was advantaged by a previous treatment due to the sputtering of the surface by the argon ions at low energy 300 eV with a current density 2 μA/cm² followed by heating in UHV at 300°C. Our results were monitored by the analysis techniques including the Auger electron spectroscopy (AES) and the electron energy loss spectroscopy (EELS) well suited to study the surface with respect to physical structure and chemical composition.

The article describes the approaches for a reliable, quantitative compositional analysis of lead-free perovskite ceramics in powder and bulk forms that contain volatile alkaline compounds. The combination of scanning electron microscopy (SEM) and transmission electron microcopy (TEM) with electron-probe analytical techniques, such as energy-dispersive X-ray spectroscopy (EDS), wavelength-dispersive X-ray spectroscopy (WDS) and electron-energy-loss spectroscopy (EELS) makes it possible to determine the true chemical composition, from precursor powders to synthesized ceramics or single crystals. The microscale (SEM) and nanoscale (TEM) analytical methods also give an insight into the local variations of the chemical composition.

We compute, from first principles, the dielectric function and electron energy loss spectrum (EELS) of an oxidized Si(100)(2×2) surface. The surface local field effect is found to be important for the calculation of EELS in a reflection geometry. Theoretical problems that arise when local fields are included within the periodic supercell approach are discussed in detail.