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Auger electron spectroscopy and electron energy loss spectroscopy (EELS) have been used to characterize the oxide InPO4 whose thickness is about 10 A˚ as grown on the substrate InP (1 0 0). The behaviour of the surface was studied following either electron irradiation or heating in UHV. The high sensitivity of the EELS, showed a structural change of the surface after irradiation with electrons of 5 keV energy, InPO4 being sensitive to the electron beam. However, this surface oxide appeared to be stable when heated in UHV at 450°C. [Copyright &y& Elsevier]

We have used Auger and electron energy loss spectroscopy to study the effect of temperature on InGaAs and InPO4 grown on InP. The thickness of InPO4 is of about 10 Å whereas that of InGaAs is of about 800 Å. InPO4 is of great interest because it protects InP from loss of stoichiometry when heated to 450 °C. The InGaAs system heated at 450 °C seems to be unstable; metallic indium appears on the surface in conjunction with formation of GaAs. [Copyright &y& Elsevier]

Abstract: The goal of this research is to highlight the effectiveness of associating the spectroscopic methods EELS and EPES in the study of thin film grown on substrates. We use the great sensitivity of the Electron Energy Loss Spectroscopy (EELS) and the Elastic Peak Electron Spectroscopy (EPES) to study native InPO4 oxide of thin thickness (10Å) grown on InP by UV/ozone oxidation. By varying the primary energy of the electron beam and the incidence angle, we give interesting results related to the chemical and the physical analyses of InPO4/InP system. These spectroscopic methods reveal the homogeneity of the chemical composition of InPO4 on the surface. Furthermore, the electron irradiation of InPO4/InP leads to the breaking of chemical bonds between the species of InPO4 and InP to form a new oxide In2O3 on the surface. We show that the heating of InPO4/InP at 450°C in UHV allows a good reconstruction of the surface with elimination of defects on the surface and at the interface. Thus, the surface becomes more stable to impede all oxidation processes due to the electron beam irradiation even for a time as long as 30min. [Copyright &y& Elsevier]

Abstract: The interaction of ions with matter plays an important role in the treatment of material surfaces. In this paper we study the effect of argon ion bombardment on the InSb surface in comparison with the InP one. The Ar+ ions, accelerated at low energy (300eV) lead to compositional and structural changes in InP and InSb compounds. The InP surface is more sensitive to Ar+ ions than that of InSb. These results are directly inferred from the qualitative Auger electron spectra (AES) and electron energy loss spectroscopy (EELS) analysis. However, these techniques alone do not allow us to determine with accuracy the disturbed depth in Ar+ ions of InP and InSb compounds. For this reason, we combine AES and EELS with the simulation method TRIM (transport and range of ions in matter) to show the mechanism of interaction between the ions and the InP or InSb and hence determine the disturbed depth as a function of Ar+ energy. [Copyright &y& Elsevier]

In the present work, we report on theoretical studies of thermodynamic properties, structural and dynamic stabilities, dependence of unit-cell parameters and elastic constants upon hydrostatic pressure, charge carrier effective masses, electronic and optical properties, contributions of interband transitions in the Brillouin zone of the novel Tl 2 HgGeSe 4 crystal. The theoretical calculations within the framework of the density-functional perturbation theory (DFPT) are carried out employing different approaches to gain the best correspondence to the experimental data. The present theoretical data indicate the dynamical stability of the title crystal and they reveal that, under hydrostatic pressure, it is much more compressible along the a-axis than along the c-axis. Strikingly, the charge effective mass values ( m e ∗ and m h ∗ ) vary considerably when the high symmetry direction changes indicating a relative anisotropy of the charge-carrier's mobility. Furthermore, the Young modulus and compressibility are characterized by the maximum and minimum values ( E max and E min ) and ( β max and β min ) that are equal to (62.032 and 28.812) GPa and (13.672 and 6.7175) TPa -1 , respectively. Additionally, we have performed calculations of the Raman spectra (RS) and reached a good correspondence with the experimental RS spectra of the Tl 2 HgGeSe 4 crystal. The XPES associated to RS constitutes powerful techniques to explore the oxidized states of Se and Ge in Tl 2 HgGeSe 4 system., (© 2024. The Author(s).)