Thermal stability of neodymium aluminates high- dielectric deposited by liquid injection MOCVD using single-source heterometallic alkoxide precursors

Abstract

Thin films of neodymium aluminate (NdAlO x) have been deposited by liquid injection metalorganic chemical vapor deposition (MOCVD) using the bimetallic alkoxide precursor [NdAl(OPr i)6(Pr i OH)]2. The effects of high-temperature postdeposition annealing on NdAlO x thin films are reported. The as-deposited thin films are amorphous in nature. X-ray diffraction (XRD) and medium energy ion scattering (MEIS) show, respectively, no crystallization or interdiffusion of metal ions into the substrate after annealing at 950C. The capacitance-voltage (C-V) and current-voltage (I-V) characteristics of the thin films exhibited good electrical integrity following annealing. The dielectric permittivity (κ) of the annealed NdAlO x was 12, and a density of interface states at flatband (D it) of 4.01 10 11 cm -2eV -1 was measured. The deposited NdAlO x thin films are shown to be able to endure high-temperature stress and capable of maintaining excellent dielectric properties. Copyright © 2012 P. Taechakumput et al.