Thick Fe2O3, Fe3O4 films prepared by the chemical solution deposition method

Fe2O3, Fe3O4 films have been prepared from Fe(OCH2CH(CH3)2)3–(CH3)2CHCH2OH–2.2′-diethanola- mine (DEA)–poly(vinylpyrrolidone) (PVP) solutions by the spin-(SC) and dip-coating (DC) technique on SiO2 and Si substrates. The maximum film thickness achieved without crack formation has been increased by incorporation of PVP (relative molecular weights 40000 and 360000) into the precursor solution. The stability of the precursor solutions was remarkably increased by addition of DEA. Compact, dense, and crack-free Fe2O3 films with thicknesses \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\geq$$\end{document} 900 nm (DC), \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\geq$$\end{document} 450 nm (SC), have been obtained via single-step deposition cycle. Higher-molecular-weight PVP has been more effective in increasing the thickness. The minimum concentration of DEA, which results in pronounced increase of solutions stability, is about RP (n(DEA)/n(Fe) = 0.1). The high content of carboneous residue in the pyrolysed Fe2O3 films promotes the formation of Fe3O4 films via reduction in a gas flow of H2/N2 gas mixture. Microstructure, surface morphology, and magnetic properties of the films have been also investigated using SEM, AFM, and SQUID, respectively.