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Thin films of La1-xSrxFeO3 have been prepared by the ALD (atomic layer deposition) technique using La(thd)3 (Hthd = 2,2,6,6-tetramethylheptane-3,5-dione), Sr(thd)2, Fe(thd)3, and ozone as precursors. A so-called ALD window is found in the temperature range 200 to 360 degrees C for LaFeO3. The effect of the pulsing procedure for the precursors on the composition of the films is examined. The results are discussed in relation to a model which ascribes differences between pulsed and obtained stoichiometries to individually different surface-area demands of the precursors. The La1-xSrxFeO3 films turned out to contain only small amounts of carbonate impurities despite the fact that films prepared from Sr(thd)2 and ozone under the same conditions contains virtually pure SrCO3. Films of La1-xSrxFeO3 have been deposited on substrates of (amorphous) soda-lime glass and single crystals of Si(100), SrTiO3(100), and LaAlO3(012). Annealed films on soda-lime glass and Si(100) substrates turned out to be polycrystalline with virtually random orientation of the crystallites. Those on MgO(100) and SrTiO3(100) substrates showed some degree of crystal orientation, whereas the annealed films on LaAlO3(012) proved to contain distinctly oriented crystallites with mosaic features.

Thin films of iron cobalt oxides with spinel-type structure are made by the atomic layer deposition (ALD) technique using Fe(thd)3 (Hthd = 2,2,6,6-tetramethylheptane-3,5-dione), Co(thd)2, and ozone as precursors. Pulse parameters for ALD-type growth are established and such growth can be achieved at deposition temperatures between 185 and 310 degrees C. Films have been deposited on amorphous soda-lime glass and single-crystalline substrates of Si(100), MgO(100), and alpha-Al2O3(001) which all provide crystalline films, but with various orientations and crystallite sizes. Application of an external magnetic field during the film growth does not influence film growth characteristics (growth rate, crystallinity, topography etc.). Magnetization data are reported for phase-pure films of spinel-type structure with composition Fe2CoO4.

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