Thermal Stability of Neodymium Aluminates High‐<i>κ</i> 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 950°C. 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 −2 eV −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.