Chemical vapor deposition growth of Fe3O4 thin films and Fe/Fe3O4 bi-layers for their integration in magnetic tunnel junctions

A possible route for the synthesis of Fe3O4, Fe, and Fe/Fe3O4 bi-layers with chemical vapor deposition by employing the same Fe-3(CO)(12) carbonyl precursor is presented. The comprehensive structural, chemical, and morphological investigation of the as-deposited thin single films and hi-layers is performed by X-ray diffraction, X-ray reflectivity, Raman spectroscopy, and time-of-flight secondary ion mass spectrometry depth profiling. We present the possibility of performing the deposition of pure metallic Fe and Fe3O4/gamma-Fe2O3 by adjusting the deposition pressure from 10(-3)/(-4) Pa to 1 Pa, respectively. The integration of Fe3O4 thin films in a magnetic tunnel junction stack fully synthesized by in situ atomic layer and chemical vapor deposition processes is also presented, showing good stack stability and marginal interdiffusion. (C) 2011 Elsevier B.V. All rights reserved.