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The relative sputtering yield of amorphous carbon with respect to polycrystalline nickel at Ar-ion bombardment was determined by means of Auger electron spectroscopy depth profiling as a function of the angle of incidence and projectile energy in the ranges of 49°–88° and 0.3–1 keV, respectively. It was found that the relative sputtering yield YC/YNi strongly increases with angle of incidence from 49° to 82°. At around 80° the sputtering yield of C is higher than that of Ni. Above 82° no dependence on the angle of incidence was found. The relative sputtering yield weakly depends on the energy of the projectile. The experimental results will be explained by the help of transport of ion in solid (TRIM) simulations. [ABSTRACT FROM AUTHOR]

Abstract: To understand the various effects induced by the ion bombardment one needs to know the sputtering yields for the sputtering conditions applied. Experimental data are rare however, and the reliability of the calculated values should be checked. Thus the measurement of sputtering yield is important. Recently, we have published a work where we have applied AES depth profiling to determine the relative sputtering yield [Barna A, Menyhard M, Kotis L, Kovacs GyJ, Radnoczi G, Zalar A, et al. J Appl Phys 2005; 98:024901–6]. In this communication, we will describe the method in a more detailed way discussing the reliability as well. It will be applied for Si/Cr multilayer structure (similar to those used in devices of integrated electronics) consisting three Si and three Cr layers sputter deposited onto smooth silicon substrates. The ion energy and projectile were 1keV and Ar+, respectively. The angle of incidence varied in the range 22°–87°. The reliability of the derived relative sputtering yields will be discussed and will be compared with those provided by the available simulation. [Copyright &y& Elsevier]

Abstract: The steady-state surface compositions of the polar (O and Zn terminated) faces of ZnO{0001} produced by low energy (0.3–2keV) Ar+ ion bombardment were studied by Auger electron spectroscopy and electron energy loss spectroscopy. The alterations produced by the ion bombardment using different ion energies were monitored by calculating the intensity ratios of the low and high energy Zn Auger peaks (59eV and 994eV, respectively); Zn and O Auger peaks (59eV and 510eV, respectively). Based on the dependence of these ratios on the ion energy and termination of the surface, we could conclude that the stability of the Zn face is higher against the low energy argon ion bombardment-induced compositional changes than that of the O face. [Copyright &y& Elsevier]

Abstract: It has been shown recently that in case of bilayers ion bombardment induced interface roughening occurs if the sputtering yields of the adjacent layers are strongly different. Now we checked the effect of this mechanism on AES depth profiling if the thickness at least one of the layers is small compared to the thickness of ion mixed layer. It turned out that in this case the ion bombardment induced interface roughening is negligible, since the ion mixing eliminates the differences of the sputtering yields. [Copyright &y& Elsevier]

Abstract: The steady state surfaces of ion bombarded 3C-, 4H- and 6H-SiC samples were studied by means of reflected electron energy loss spectroscopy (REELS). The REELS exhibit a well-defined loss peak in the region of about 20eV. The position of the maximum of the loss peak depends on the bombarding ion energy (decreasing with increasing ion energy), and on the primary electron beam energy (increasing with increasing primary energy). This behavior can be explained if we suppose that the plasmon energy in the altered layer (produced by ion bombardment) is different from that of the unaltered bulk. In this case the measured loss peak is the sum of two overlapping plasmon peaks. With modeling the system as a homogeneous altered layer and a homogeneous unaltered substrate the plasmon energy in the altered layer was derived to be 19.8eV. The large change of the plasmon energy with respect to the bulk value of 23eV is explained by a thin low density overlayer on the surface of the sample produced by the ion bombardment. [Copyright &y& Elsevier]

Abstract: Medium-energy (some tens of keV) ion irradiation is frequently used in various technologies. It is well known that during this irradiation serious alterations are introduced to the material, changing its structure, composition, etc. While there are studies on the amorphization, no results have been reported on the medium-energy ion beam-induced mixing, however. In this work, we present Auger electron spectroscopy (AES) depth profiling measurements of Si/Cr multilayer samples, which were irradiated by various ions (Ga+, Ar+, CF4 +) of 20keV applying angles of incidence of 5° (Ga+), 65° (Ga+) and 75° (Ar+, CF4 +). The ion beam-induced mixing at the Si/Cr interface (the broadening of the interface) was measured as a function of the removed layer thickness. The weakest and strongest ion mixing (for a given removed layer thickness) were found for CF4 + and Ga+ 5° irradiations, respectively. In the case of Ga+ irradiation, the larger the angle of incidence the weaker the ion mixing. The extent of mixing does not correlate with the corresponding projected range. Comparison of the experimentally measured ion mixed profiles with those given by dynamic TRIM simulations gave poor agreement for Ar+ and fails for Ga+ irradiations, respectively. [Copyright &y& Elsevier]

Ion sputtering induced surface composition changes by applying various ions (He+, Ne+, Ar+, Xe+) in the energy range of 0.2–1.5 keV, was measured by AES on the polar faces of 6H–SiC{0 0 0 1}. Carbon enrichment was observed on both faces, and it was different if Ne+, Ar+, Xe+ ion sputtering was applied with ion energy lower than 0.4–0.8 keV (depending on projectile); no different enrichment was found for He+ ion bombardment at any energy (in this range). Thus C/Si ratio measured by AES after low energy ion (e.g. Xe+) bombardment can be used to identify polarity of the surface. [Copyright &y& Elsevier]