Premium
Structural stratification of Sr 1 − x Ca x RuO 3 thin films: Influence of aging process
Author(s) -
Młynarczyk Marcin,
Szot Krzysztof,
Poppe Ulrich,
Breuer Uwe,
Mi Shaobo,
Psiuk Bronisław,
Görlich Edward A.,
Tomala Krzysztof,
Waser Rainer
Publication year - 2013
Publication title -
physica status solidi (a)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.532
H-Index - 104
eISSN - 1862-6319
pISSN - 1862-6300
DOI - 10.1002/pssa.201228217
Subject(s) - thin film , high resolution transmission electron microscopy , analytical chemistry (journal) , x ray photoelectron spectroscopy , materials science , sputtering , tetragonal crystal system , rutherford backscattering spectrometry , transmission electron microscopy , epitaxy , chemistry , layer (electronics) , crystallography , nanotechnology , crystal structure , chromatography , physics , nuclear magnetic resonance
Epitaxial Sr 1 − x Ca x RuO 3 thin films were grown on SrTiO 3 and LaAlO 3 substrates with use of high pressure dc‐sputtering. A number of complementary methods: X‐ray diffraction (XRD), Rutherford backscattering (RBS), high resolution transmission electron microscopy (HRTEM), time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS), atomic force microscopy (AFM), and X‐ray photoemission spectroscopy (XPS) was used to characterize both in‐depth and lateral structure features. Fully strained thin films were obtained with a tetragonal lattice cell pronouncedly elongated in an out‐of‐plane direction, independent on details of deposition conditions. Growth types varied from a single layer‐by‐layer two‐dimensional (2D) mode to three‐dimensional (3D) spiral precipitations of different size. Interface layer between the substrate and the thin film as well as its surface suffer from considerable deviations from nominal stoichiometry, basically resulting from Ru deficiency. Samples stored under normal conditions undergo further compositional change of the surface region. The process of aging, extended over several days, involves incorporation of water and carbon dioxide present in an ambient atmosphere and a subsequent surface reconstruction. For samples deposited on SrTiO 3 the valence band is indicative of a metallic character of the sample interior regardless of Ca content. The heterogeneous in‐depth profile of the thin films is extremely important in fabrication of nanodevices, especially those based on ultrathin layers.Examination summary of Sr 0.8 Ca 0.2 RuO 3 thin films, deposited on SrTiO 3 , methods used and essential conclusions.