We have investigated the magnetic and transport properties of nanoscaledFe3O4 films obtained from Chemical Vapor Deposition (CVD) technique using[FeIIFe2III(OBut)8] and [Fe2III(OBut)6] precursors. Samples were deposited ondifferent substrates (i.e., MgO (001), MgAl2O4 (001) and Al2O3 (0001)) withthicknesses varying from 50 to 350 nm. Atomic Force Microscopy analysisindicated a granular nature of the samples, irrespective of the synthesisconditions (precursor and deposition temperature, Tpre) and substrate. Despitethe similar morphology of the films, magnetic and transport properties werefound to depend on the precursor used for deposition. Using [FeIIFe2III(OBut)8]as precursor resulted in lower resistivity, higher MS and a sharpermagnetization decrease at the Verwey transition (TV). The temperaturedependence of resistivity was found to depend on the precursor and Tpre. Wefound that the transport is dominated by the density of antiferromagneticantiphase boundaries (AF-APB's) when [FeIIFe2III(OBut)8] precursor and Tpre =363 K are used. On the other hand, grain boundary-scattering seems to be themain mechanism when [Fe2III(OBut)6] is used. The Magnetoresistance (MR(H))displayed an approximate linear behavior in the high field regime (H > 796kA/m), with a maximum value at room-temperature of \sim2-3% for H = 1592 kA/m,irrespective from the transport mechanism.
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