Niobium tetrakis(ethoxide) (dibenzoylmethanate) Nb(OEt)4(dbm) (dbm = dibenzoyl methanate = 1,3-diphenyl-1,3-propanedionate) is mononuclear, with distorted octahedral configuration, according to single-crystal X-ray diffraction (XRD).
The complex Nb(OEt)4(dbm) was applied as precursor for the growth of thin Nb2O5 films by liquid injection MOCVD (using Nb(OEt)4(dbm) precursor solution). The complex represented unusual thermal stability caused by the presence of the dbm ligand. Therefore, Nb2O5 layers could be deposited only at relatively high substrate temperatures (>650 °C).[i]
[i] P.A. Williams, A.C. Jones, P.J. Wright, M.J. Crosbie, J.F. Bickley, A. Steiner, H.O. Davies, T.J. Leedham, Chem. Vapor Dep., 2002, Vol. 8, Iss.3, p.110-116, «The Unusual Thermal Stabilization of MOCVD Precursors by the Dibenzoyl Methanate Group: Liquid Injection MOCVD of Tantalum Oxide and Niobium Oxide Using M(OEt)4(dbm) Precursors», doi.org/10.1002/1521-3862(20020503)8:3<110::AID-CVDE110>3.0.CO;2-U
Niobium heteroligand alkoxide-diketonate complex Nb(OiPr)4(thd), combined with potassium tert-butoxide, was applied as volatile metal-organic precursor to single-source powder
flash evaporation MOCVD growth of epitaxial thin films of KNbO3, the material potentially applicable in surface acoustic wave (SAW) and nonlinear optic devices. The layer microstructure was dependent on the substrate type (MgO or SrTiO3) and deposition temperature.
High second harmonic generation (SHG) output was used to verify the device quality of the deposited KNbO3 films; the dependence of the phase transition temperature on the oxygen non-stoichiometry of films was proven. [i]
[i] M.V. Romanov, I.E. Korsakov, A.R. Kaul, S.Yu. Stefanovich, I.A. Bolshakov, G. Wahl, Chem. Vapor Dep., 2004, Vol.10, Iss.6, p.318-324, « MOCVD of KNbO3 Ferroelectric Films and their Characterization », https://doi.org/10.1002/cvde.200306302, https://onlinelibrary.wiley.com/doi/abs/10.1002/cvde.200306302
Niobium tetrakis(isopropoxide) 2,2,6,6-tetramethyl-3,5-heptanedionate, Nb(OiPr)4(thd), was investigated as precursor for the growth of single phase Nb-doped ferroelectric Pb(Zr,Ti)O3
(PZT) thin films by liquid delivery MOCVD, layers of PZT(Nb) having good ferroelectric properties were obtained. Nuclear magnetic resonance (NMR) studies have demonstrated that in solution Nb(OiPr)4(thd) exhibited chemical compatibility and stability with
the Pb, Zr, and Ti co-reactants. Thermal analysis of Nb(OiPr)4(thd) revealed its sufficient volatility and thermal stability. [i]
[i] I.-S. Chen, J. F. Roeder , T. E. Glassman, T. H. Baum, Chem. Mater., 1999, 11 (2), pp 209–212, “Liquid Delivery MOCVD of Niobium-Doped Pb(Zr,Ti)O3 Using a Novel Niobium Precursor”, DOI: 10.1021/cm980503s, http://pubs.acs.org/doi/abs/10.1021/cm980503s
Nb(OEt)(thd)4 (combined with Mg(thd)2) was applied for the MOCVD growth of Pb(Mg0.33Nb0.66)O3 (PMN), and Pb(Mg0.33Nb0.66)O3-PbTiO3 (PMN-PT) thin films on Si and Pt/Ti/SiO2/Si substrates by using ultrasonic nebulization of precursor solution.[210, 211]