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The increasing need to miniaturize capacitor devices is demanding for progressively higher dielectric constant materials. Recent studies have demonstrated that the calcium copper titanate, CaCu3Ti4O12 (CCTO), single crystals and ceramics possess impressive dielectric constant values of about 10 working at 1 MHz which remain constant in the 100-600K temperature range and slightly depend upon work frequency in the 10-10 Hz range. Fabrication of thin films becomes now a required issue to understand their properties and evaluate potentialities for device integration. The synthesis of a multi-element oxide phase often requires considerable efforts to define the appropriate deposition conditions for the fabrication of high quality thin films and in particular the MOCVD growth process depends critically on the availability of volatile, thermally stable precursors. CaCu3Ti4O12 (CCTO) thin films have been successfully deposited on LaAlO3 (100) single substrates and on Pt/TiO2/SiO2/Si(100) stacks using Metal Organic Chemical Vapor Deposition technique, a suitable method even for large-scale production. A novel approach based on a molten multi-component precursor source has been applied. The molten mixture consists of the Ca(hfa) 2 •tetraglyme, Ti(tmhd)2(i-Opr)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; i-Opr = isopropoxide] precursors. 6-8 Film complete structural and morphological characterizations have been carried out by several techniques [X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM)]. The in-situ deposited CCTO (001) films on LaAlO3 (001) substrates are of high quality as evidenced by their inplane and out-of-plane alignments investigated using Xray and electron transmission diffraction patterns. CCTO films grown on Pt/TiO2/SiO2/Si(100) industrial substrates are polycrystalline (Figure 1) and present more disordered morphologies (Figure 2). Moreover, the electrical characterization at micro (Figure 2) and nanometer scale has been performed. The permittivity imaging provided at nanometer scale by Scanning Impedance Microscopy provided a correlation between the physical properties and structural characteristics. The nano impedance modulus and phase have been detected and the permittivity of the single CCTO layer has been calculated to be about 8000 at 90 kHz. Figure 1. XRD of CCTO polycrystalline films on Pt electrode and CCTO unit cell as inset.