Preparation and structural properties of YBCO films grown on GaN/ c-sapphire hexagonal substrate

• Published in: Applied surface science Vol. 256; no. 18; pp. 5618 - 5622
• Main Authors: Chromik, Š., Gierlowski, P., Španková, M., Dobročka, E., Vávra, I., Štrbík, V., Lalinský, T., Sojková, M., Liday, J., Vogrinčič, P., Espinos, J.P.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01.07.2010; Elsevier
• Subjects: Auger electron spectroscopy; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Deposition by sputtering; Diffraction; Direct current; Electron and ion emission by liquids and solids; impact phenomena; Epitaxial growth; Exact sciences and technology; Gallium; Gallium nitrides; GaN substrates; Infrared and Raman spectra; Magnetron sputtering; Materials science; Maxima; Methods of deposition of films and coatings; film growth and epitaxy; Photoemission and photoelectron spectra; Physics; Pulsed laser deposition (PLD); Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Transmission electron microscopy; X-ray diffraction; X-rays; YBCO superconductors; YBCO thin films; 74.72h; Magnetron sputtering; YBCO thin films; Transmission electron microscopy; Pulsed laser deposition (PLD); GaN substrates; X-ray diffraction; Auger electron spectroscopy; 73.61Ey; Inorganic compounds; Epitaxy; 73.61 Ey; XRD; Gallium nitride; Thin films; Cathode sputtering; High-Tc superconductors; X-ray analysis; Quaternary compounds; Buffer layer; Epitaxial layers; Semiconductor materials; Magnesium oxide; Transition element compounds; Pulsed laser deposition; Film growth; AES; Magnetrons; Diffusion barriers; Barium oxide; Preparation; Yttrium oxide; Copper oxide; X-ray photoelectron spectra
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2010.03.035

Epitaxial YBCO thin films have been grown on hexagonal GaN/ c-sapphire substrates using DC magnetron sputtering and pulsed laser deposition. An MgO buffer layer has been inserted between the substrate and the YBCO film as a diffusion barrier. X-ray diffraction analysis indicates a c-axis oriented growth of the YBCO films. Φ-scan shows surprisingly twelve maxima. Transmission electron microscopy analyses confirm an epitaxial growth of the YBCO blocks with a superposition of three a– b YBCO planes rotated by 120° to each other. Auger electron spectroscopy and X-ray photoelectron spectroscopy reveal no surface contamination with Ga even if a maximum substrate temperature of 700 °C is applied.