Regensburg 2013 – wissenschaftliches Programm

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DS: Fachverband Dünne Schichten

DS 13: Poster Session III: Layer properties: electrical, optical and mechanical properties; Thin film characterization: structure analysis and composition (XRD, TEM; XPS, SIMS, RBS..)

DS 13.13: Poster

Montag, 11. März 2013, 17:00–20:00, Poster B1

Temperature and time dependent in-situ crystallization of strontium titanate thin films — •Florian Hanzig¹, Carsten Richter^1,2, Juliane Hanzig¹, Erik Mehner¹, Hartmut Stöcker¹, Barbara Abendroth¹, and Dirk C. Meyer¹ — ¹TU Bergakademie Freiberg, Institut für Experimentelle Physik — ²HASYLAB bei DESY, Hamburg

Strontium titanate is a well-known transition metal oxide crystallizing in the perovskite type of structure. With its large band-gap and its mixed ionic and electronic conductivity, SrTiO₃ is a promising isolating material in metal-insulator-metal (MIM) structures for resistive switching memories. In this paper, the crystallization of amorphous strontium titanate thin films is investigated by in-situ grazing incidence x-ray diffraction using synchrotron light (Beamline E2 at DORIS III - HASYLAB / DESY, Hamburg). We focus on the crystallization mechanisms in dependence of the layer stoichiometry and heating rates. Different physical vapour deposition methods have been used to fabricate stoichiometric and Sr-rich layers. The crystallization and evolution of phase composition, crystallite size and strain of the SrTiO₃ layers were investigated for temperatures up to 950 ^∘C under atmospheric conditions. At approximately 350 ^∘C crystallization of the perovskite-type SrTiO₃ is initiated for Sr-rich electron beam evaporated layers, whereas stoichiometric sputter deposited thin films crystallize from about 500 ^∘C. During annealing a diffusion of Si from the substrate into the SrTiO₃ layer occur leading to the formation of secondary silicate phases which are detected by XPS.