For this paper the pulsed laser deposition onsingle-crystal MgO substrates of Ba_4Fe_4Ti_3O_(16) targetwas studied by transmission electron microscopy and x-raydiffraction. The initial stage of the deposition resulted in theformation of the perovskite Ba(Fe, Ti)O_3 phase in an epitaxial,cube-on-cube orientation relationship with a substrate. Furthergrowth of the pseudo-cubic phase was interrupted by theformation of oriented grains with a disordered structure. Thisdisordered structure had a mixture of lamellae of the cubic andhexagonal Ba(Fe, Ti)O_3 phases. No formation of theBa_4Fe_4Ti_3O_(16) (E) phase was observed. Formation of thedisordered phase was explained by the higher stability ofhexagonal Ba(Fe, Ti)O_3 where accommodation of Fe~(3+)occurred on a twinning plane. The development of the V-shapemorphology and a limited number of orientations of the Dstructure were explained by the faceting and columnarmorphology of the perovskite phase.
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