A nitrilo-tri-acetic-acid/acetic acid route for the deposition of epitaxial cerium oxide films as high temperature superconductor buffer layers

• Published in: Journal of solid state chemistry Vol. 183; no. 9; pp. 2154 - 2160
• Main Authors: Thuy, T.T., Lommens, P., Narayanan, V., Van de Velde, N., De Buysser, K., Herman, G.G., Cloet, V., Van Driessche, I.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.09.2010; Elsevier
• Subjects: ACETIC ACID; ATOMIC FORCE MICROSCOPY; CARBOXYLIC ACIDS; CeO 2 buffer layers; CERIUM COMPOUNDS; CERIUM IONS; CERIUM OXIDES; CHALCOGENIDES; CHARGED PARTICLES; COHERENT SCATTERING; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; CRYSTAL GROWTH METHODS; DEPOSITION; DIFFRACTION; DIP COATING; ELECTRON MICROSCOPY; EPITAXY; Exact sciences and technology; FOURIER TRANSFORMATION; HIGH-TC SUPERCONDUCTORS; INFRARED SPECTRA; INTEGRAL TRANSFORMATIONS; IONS; Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids); MATERIALS SCIENCE; Methods of deposition of films and coatings; film growth and epitaxy; MICROSCOPY; MONOCARBOXYLIC ACIDS; Nitrilo-tri-acetic-acid; ORGANIC ACIDS; ORGANIC COMPOUNDS; OXIDES; OXYGEN COMPOUNDS; Physics; RARE EARTH COMPOUNDS; SCANNING ELECTRON MICROSCOPY; SCATTERING; SOL-GEL PROCESS; Sol–gel; Species distribution simulation; SPECTRA; Structure and morphology; thickness; Superconductor; SUPERCONDUCTORS; SURFACE COATING; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); TEMPERATURE RANGE; TEMPERATURE RANGE 1000-4000 K; Thin film structure and morphology; THIN FILMS; TRANSFORMATIONS; TYPE-II SUPERCONDUCTORS; X-RAY DIFFRACTION; Thin films; Superconductor; Nitrilo-tri-acetic-acid; Species distribution simulation; Sol–gel; CeO 2 buffer layers; Atomic force microscopy; buffer layers; Fourier transform spectroscopy; Material processing; Spectroscopic ellipsometry; Crystal orientation; XRD; Cerium oxide; Precursor; Texture; Sol―gel; Metallic thin films; Scanning force microscopy; High-Tc superconductors; Attenuated total reflection; Dip coating; Fourier-transformed infrared spectrometry; Sol-gel process; Pole figures; Buffer layer; Scanning electron microscopy; Texture analysis; Epitaxial layers; Digital simulation; Carbon; Layer thickness; Operating conditions; Ce0; Beryllium; Acetic acid
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2010.07.009

A water based cerium oxide precursor solution using nitrilo-tri-acetic-acid (NTA) and acetic acid as complexing agents is described in detail. This precursor solution is used for the deposition of epitaxial CeO 2 layers on Ni-5at%W substrates by dip-coating. The influence of the complexation behavior on the formation of transparent, homogeneous solutions and gels has been studied. It is found that ethylenediamine plays an important role in the gelification. The growth conditions for cerium oxide films were Ar-5% gas processing atmosphere, a solution concentration level of 0.25 M, a dwell time of 60 min at 900 °C and 5–30 min at 1050 °C. X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscopy (AFM), pole figures and spectroscopic ellipsometry were used to characterize the CeO 2 films with different thicknesses. Attenuated total reflection-Fourier transform infrared (ATR–FTIR) was used to determine the carbon residue level in the surface of the cerium oxide film, which was found to be lower than 0.01%. Textured films with a thickness of 50 nm were obtained. Study of the complexation and hydrolysis behavior of Ce 4+ ions in the presence of nitrilo-tri-acetic acid and the subsequent development of an aqueous chemical solution deposition route suited for the processing of textured CeO 2 buffer layers on Ni–W tapes. [Display omitted]