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The effect of thermal annealing on epitaxial GeSn (6.5% Sn) strained layers grown on Ge-buffered Si(100) wafers has been investigated using Rutherford backscattering spectrometry and X-ray diffraction to unambiguously determine the Sn substitutional content as well as the elastic strain in the layers. Vacuum annealing at temperatures below 400 °C for 20 min has no noticeable effect on the strain in the epitaxial layers. Once the temperature was raised above 400 °C, however, relaxation of the layer sets in and the GeSn layer has essentially completely relaxed following a 20 min anneal at 650 °C. Using Rutherford backscattering and channelling spectrometry to provide compositional information as a function of depth enables one to monitor the effect of the thermal anneal on the Sn distribution throughout the layer, and also to directly extract their substitutional fraction (i.e., their solubility in the lattice). The results obtained show that when the relaxation initially sets in both the Ge and the Sn remain firmly bound in substitutional lattice sites and it is only around 600 °C, and after substantial relaxation has taken place, that Sn is finally expelled from lattice sites and diffuses to the surface of the sample. [ABSTRACT FROM AUTHOR]

Noble gas ion sputtering combined with Auger electron spectroscopy (AES) analysis has been applied extensively for elemental composition depth profiling of the target materials. Such depth profiles have been used widely not only for elemental composition analysis but also for extracting the sputtering yields of the target materials. Despite a large number of publications on sputtering yields there are only a small number of reports (in literature) on the measured sputtering yields of indium compounds. Indium is used to dope semiconductors for electronic devices (transistor) and thin film solar cells. In order to obtain accurate depth information (for indium thin films) with Ar+ ion profiling, it is essential to have reliable sputtering yields for the In metal. In this study, the argon ion sputtering yields of indium films are reported for a range of low ion beam energies (0.5-4.0 keV). The indium films (106 nm) were deposited on SiO2 substrates under vacuum by electron beam evaporation. The films were subjected to Ar+ ion sputtering combined with AES analysis to obtain the depth profiles, which were used to extract the sputtering yield values. The obtained sputtering yield values are in the range of 2 to 6 atoms/ions for Ar+ ion beam energies in the range of 0.5-4.0 keV, respectively. The Monte Carlo simulation code, Stopping and Range of Ions in Materials (SRIM) were used to simulate the Ar+ ion bombardment of the indium film and to obtain the surface sputtering yields and influences the structures as deposited and the corresponding activities induced. These were also calculated using a semi-empirical formula developed for such predictions. The sputtering yields obtained from SRIM and the semi-empirical formula are in agreement with the experimental values. [ABSTRACT FROM AUTHOR]

The influence of 150 keV argon ions at fluences in the range of 1 × 10 12 -1 × 10 16 ions/cm 2 on the stability of the multilayer stack Pd/Zr/Pd/Ti/Pd thin films system, deposited on Ti and Ti 6 Al 4 V substrates, under thermal annealing in an H 2 environment was investigated. For samples deposited on Ti substrate, RBS revealed structural instability that increases with fluence. This is evidenced by a decrease in the intensity of layers accompanied by increased consumption of the Pd layers. This effect led to the initial individual layers becoming one compound layer and the formation of a new Ti-O-Pd layer, indicating a complete intermixing of layers at 1 × 10 16 ions/cm 2 . However, for the samples deposited on Ti 6 Al 4 V substrate, the Pd layers could still be identified and resolved, indicating an incomplete intermixing of layers. XRD revealed the structural transformation of layers via an intermixing process resulting in the formation of two new phases, TiH 2 and ZrH 2 , classified as face-centered tetragonal (FCT) crystal structures. ERDA confirmed the presence of hydrides in the system indicating the absorption of H into the system to a maximum H amount of ∼5.2 at.%, at higher fluence, for the same multilayer stack deposited on both substrates., Competing Interests: Dear Editor, Authors declare that this work is not a duplicate of any study conducted before nor any part of the work published or submitted in any journal. The authors declare that they have no conflict of interest in the publication of this article., (© 2024 The Authors.)