Tin etching from metallic and oxidized scandium thin films

The role of oxide on Sn adhesion to Sc surfaces was studied with in-situ ellipsometry, X-ray photoelectron spectroscopy and secondary electron microscopy. Sn etching with hydrogen radicals was performed on metallic Sc, metallic Sc with a native oxide, and a fully oxidized Sc layer. The results show that Sn adsorbs rather weakly to a non-oxidized Sc surface, and is etched relatively easily by atomic hydrogen. In contrast, the presence of native oxide on Sc allows Sn to adsorb more strongly to the surface, slowing the etching. Furthermore, thinner layers of scandium oxide result in weaker Sn adsorption, indicating that the layer beneath the oxide plays a significant role in determining the adsorption strength. Unexpectedly, for Sn on Sc2O3, and, to a lesser extent, for Sn on Sc, the etch rate shows a variation over time, which is explained by surface restructuring, temperature change, and hydrogen adsorption saturation

Metal diffusion properties of ultra-thin high-k Sc2O3 films

The diffusion barrier properties of Sc2O3 against metal diffusion were studied. Tin and ruthenium were used as probe materials to study the barrier properties of Sc2O3 in thickness ranges that are of relevance for gate materials. Tin deposition and hydrogen radical etching from Sc2O3 layers of 0.5-1.5 nm thickness, deposited on Ru, show that these Sc2O3 layers effectively block the diffusion of Sn into Ru. We show that Sn adhesion and etching depends strongly on the thickness of the Sc2O3 film. The etch-rate is found to be inversely proportional to the Sc2O3 layer thickness, which we attribute to Sc2O3 becoming a more effective charge transfer barrier at larger thicknesses

Total bilirubin in athletes, determination of reference range

The purpose of this study was to determine a typical reference range for the population of athletes. Results of blood tests of 339 athletes (82 women and 257 men, aged 18-37 years) were retrospectively analysed. The subjects were representatives of different sports disciplines. The measurements of total bilirubin (BIT), iron (Fe), alkaline phosphatase (ALP), alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) were made using a Pentra 400 biochemical analyser (Horiba, France). Red blood cell count (RBC), reticulocyte count and haemoglobin concentration measurements were made using an Advia 120 haematology analyser (Siemens, Germany). In groups of women and men the percentage of elevated results were similar at 18%. Most results of total bilirubin in both sexes were in the range 7-14 μmol ∙ L-1 (49% of women and 42% of men). The highest results of elevated levels of BIT were in the range 21-28 μmol ∙ L-1 (12% of women and 11% of men). There was a significant correlation between serum iron and BIT concentration in female and male athletes whose serum total bilirubin concentration does not exceed the upper limit of the reference range. Elevated concentrations of total bilirubin appear to be due to changes caused by regular exercise. The obtained upper limit of the reference range for total bilirubin concentration in the group of athletes is 29.0 μmol ∙ L-1. It seems reasonable to use dedicated reference values for total bilirubin concentration in relation to the group of athletes

Adsorption and Dissociation of CO2 on Ru (0001)

The adsorption and dissociation of carbon dioxide on a Ru(0001) single crystal surface was investigated by reflection–absorption infrared spectroscopy (RAIRS) and temperature-programmed desorption (TPD) spectroscopy for CO2 adsorbed at 85 K. RAIRS spectroscopy shows that the adsorption of CO2 on a Ru(0001) single crystal is partially dissociative, resulting in CO2 and CO. The CO vibrational mode was also observed to split into two distinct modes, indicating two general populations of CO present at the surface. Furthermore, a time-dependent blue-shift is observed, which is characteristic of increasing CO surface coverage. TPD showed that coverages of up to 0.3 ML were obtained, and no evidence for chemisorption of oxygen on ruthenium was found