CdTiO3 thin films from an octa-nuclear bimetallic single source precursor by aerosol assisted chemical vapor deposition (AACVD)

Abstract

Mesoporous, crack-free and crystalline CdTiO₃ thin films were deposited by aerosol assisted chemical vapour deposition (AACVD) from a single source hetero-bimetallic precursor, [Cd₄Ti₄(dmae)₄(TFA)₈(OAc)₄O₆] 1 [where dmae = N,N-dimethyaminoethanolate, TFA = trifluoroacetate, Oac = acetate]. The precursor 1, prepared by a simple chemical reaction, was characterized by melting point, elemental analysis, thermal analysis (TGA/DTA) and single crystal X-ray analysis. 1 undergoes facile thermal decomposition at 450 °C and has sufficient solubility in common organic solvents to be usable in aerosol assisted chemical vapour deposition of CdTiO₃ thin films. The thin films of CdTiO₃ deposited on a fluorine doped SnO₂ coated conducting glass substrate in one single step were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive (EDX) and Rutherford backscattering spectrometry (RBS). The results indicate that the nanoparticles of grain size ranging from 30–50 nm are homogeneously dispersed with no preferred orientation and both the Cd and Ti atoms are homogeneously distributed in a 1 : 1 atomic ratio. UV-VIS-NIR and Defuse Reflectance spectroscopies affirm a band gap of 3.4 eV where electrical measurements show that the films possess n-type conductivity.