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The complex, Mn(hfa)2•tmeda [(H-hfa = 1,1,1,5,5,5-hexafluoro-2,4-pentandione, tmeda = N,N,N′,N′-tetramethylethylendiamine)], is synthesized in a single-step reaction and characterized by elemental analysis, thermal analysis, and infrared (IR) spectroscopy. The solid-state crystal structure of Mn(hfa)2•tmeda provides evidence of a mononuclear structure. The thermal analyses show that the complex is thermally stable and can be evaporated to leave less than 2% residue. The complex properties are compared with the first generation, commercially available MnII and MnIII precursors, Mn(acac)2 (Hacac = acetylacetone) and Mn(tmhd)3 (Htmhd = 2,2,6,6-tetramethyl-3,5-heptanedione), respectively. Mn(hfa)2•tmeda represents the first example of manganese(II) precursor that can be used in the liquid phase without decomposition, thus providing constant evaporation rates, even for long deposition times. It is successfully applied to the reduced-pressure, metal-organic (MO)CVD of the Mn3O4 phase.

Thin films of CaCu3Ti4O12 (CCTO) are successfully deposited by metal-organic (MO)CVD on (001)SrTiO3 substrates. An interesting approach, based on a molten multi-component precursor source, is applied. The molten mixture consists of the Ca(hfa)2 center dot tetraglyme, Ti(tmhd)2(OiPr)2, and Cu(tmhd)2 [Hhfa?=?1,1,1,5,5,5-hexafluoro-2,4-pentanedione; tetraglyme?=?2,5,8,11,14-pentaoxapentadecane; Htmhd?=?2,2,6,6-tetramethyl-3,5-heptandione; OiPr?=?iso-propoxide] precursors. It is also found that, in the present case of a relatively large lattice mismatch (similar to 5%), the epitaxial growth can be achieved by a careful optimization of deposition parameters. Film structural and morphological characterization is carried out using several techniques; X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). A complete comparison between films deposited by two main processes is carried out in order to understand the kinetic and thermodynamic issues involved in the MOCVD epitaxial growth.