% IMPORTANT: The following is UTF-8 encoded. This means that in the presence % of non-ASCII characters, it will not work with BibTeX 0.99 or older. % Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or % “biber”. @MASTERSTHESIS{Schffmann:830337, author = {Schöffmann, Patrick}, title = {{P}reparation and {C}haracterisationof {T}hin {S}r{C}o{O}$_x$ {F}ilms}, school = {Technische Universität München}, type = {MS}, reportid = {FZJ-2017-03901}, pages = {89}, year = {2017}, note = {Technische Universität München, Masterarbeit, 2017}, abstract = {Transition metal oxides are an extremely interesting class of materials, exhibiting a wide range of properties, from ferromagnetism to antiferromagnetism, frominsulating to conducting, superconductivity, multiferroicity, and many more. One special system is strontium cobaltite (SrCoO$_{x}$). In its fully oxidized state SrCoO$_3$ it is a ferromagnetic, conducting perovskite. If, however, the oxygen content is changed slightly to SrCoO$_{2.5}$, the oxygen vacancies form channels, changing the crystalline structure to a brownmillerite, and the magnetic and conductive properties reverse to an antiferromagnetic insulator. These two crystal structures can be topotactically transformed into one another without destroying the crystallinity. This property makes SrCoO$_x$ suitable for a large variety of applications, e.g. as a cathode material and catalyst for redox reactions in fuel cells or magnetic switches via epitaxial strain. To take advantage of the unique possibilities of SrCoO$_x$ , particularly in the field of thin film devices, it is imperative to be able to grow Sr$_1$Co$_1$O$_x$ in the correct stoichiometry. The aim of this thesis is to find the correct deposition conditions for the growth of stoichiometric SrCoO$_x$ thin film samples via molecular beam epitaxy (MBE), like substrate temperature, cooling speed, pressure, oxygen power, and especially the Sr and Co deposition rates. Because the samples are prepared via MBE, which does not use a target with an already defined stoichiometry like sputter deposition or pulsed laser deposition, but rather the evaporation of elemental material, the stoichiometry of the samples depends on several factors. The individual growth rates for Sr and Co do not only depend on the amount of evaporated material, but also on the sticking coeficient of the material on the substrate. As the sticking coeficient is also temperature dependent, there is a large parameter space that needs to be investigated. Therefore, samples with varying Co/Sr deposition rate ratios at different deposition temperatures were produced. The stoichiometry was analysed by Rutherford backscattering spectroscopy (RBS). The crystallinity of the samples was studied by low energy electron diffraction (LEED), reflection high energy electron diffraction (RHEED) and X-ray diffraction (XRD). To investigate the surface topography, atomic force microscopy (AFM) was performed. X-ray reflectometry (XRR) was used to determine the global surface roughness and film thickness.}, cin = {JCNS (München) ; Jülich Centre for Neutron Science JCNS (München) ; JCNS-FRM-II / JCNS-2}, cid = {I:(DE-Juel1)JCNS-FRM-II-20110218 / I:(DE-Juel1)JCNS-2-20110106}, pnm = {6212 - Quantum Condensed Matter: Magnetism, Superconductivity (POF3-621) / 6G15 - FRM II / MLZ (POF3-6G15) / 6G4 - Jülich Centre for Neutron Research (JCNS) (POF3-623) / 524 - Controlling Collective States (POF3-524)}, pid = {G:(DE-HGF)POF3-6212 / G:(DE-HGF)POF3-6G15 / G:(DE-HGF)POF3-6G4 / G:(DE-HGF)POF3-524}, experiment = {EXP:(DE-MLZ)MBE-MLZ-20151210}, typ = {PUB:(DE-HGF)19}, url = {https://juser.fz-juelich.de/record/830337}, }