Growth and Hydrogen uptake of Mg-Y thin films
2005 (English)In: Journal of Applied Physics, Vol. 97, 104903- p.Article in journal (Refereed) Published
Wedged Mg–Y films with compositions ranging from pure Mg to Mg0.83Y0.17 were grown by dc-magnetron sputtering and hydrogenated. Mg1–xYx forms a substitutional alloy, ranging from 0 to at least 17 at. % in thin films. The c lattice parameter of the film containing 17 at. % of yttrium is determined to be approximatively 1% larger than in pure Mg. Upon exposure to 1 bar of hydrogen at 300 K, the samples switch from shiny metals to colorless semiconductor. Different characteristic hydrogen depth distributions are found for different Y concentrations. At low yttrium contents, a large concentration gradient is observed, with the highest hydrogen concentration close to the Pd/Mg1–xYx interface. For yttrium concentrations larger than 7 at. %, the obtained hydrogen distribution is almost independent of depth. The optical band gap is determined to be 3.6 eV, for all the Y concentrations. The optical transmission is found to decrease for increasing Y content, which is associated with an incomplete hydride formation in the films.
Place, publisher, year, edition, pages
2005. Vol. 97, 104903- p.
IdentifiersURN: urn:nbn:se:uu:diva-75903DOI: doi:10.1063/1.1896440OAI: oai:DiVA.org:uu-75903DiVA: diva2:103814