Effect of substrate’s nature on the growth of HgBCCO thin films

• Published in: Physica. C, Superconductivity Vol. 440; no. 1; pp. 45 - 51
• Main Authors: De Barros, D., Ortega, L., Peroz, Ch, Weiss, F., Odier, P.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-07-2006; Elsevier Science
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; HgBCCO; High-tc films; Mercury based cuprate films; Physics; Solid phase epitaxy; Spray pyrolysis; Superconducting films and low-dimensional structures; Superconductivity; Mercury based cuprate films; Spray pyrolysis; HgBCCO; Solid phase epitaxy; Films; Superconductivity; Scanning electron microscopy; Stoichiometry; Spray coatings; Texture; Substrates; Thin films; Calcium oxides; Monocrystals; Critical current; Anisotropy; Barium oxides; Mercury oxides; High-Tc superconductors; Microstructure; Copper oxides; Pole figures
• ISSN: 0921-4534; 1873-2143
• DOI: 10.1016/j.physc.2006.03.064

The synthesis of HgBCCO films by spray pyrolysis on single crystals is investigated. It is shown that in conditions where the precursor is expected to give Hg-1223, Hg-1212 grows on LaAlO
3 (0
0
1) while Hg-1223 grows on MgO (0
0
1). The samples are analysed by X-ray pole figures, SEM and critical current measurements. Both samples were superconducting but the sample on MgO had a negligible
I
c while 17
A was measured on LAO at 77
K (sf). These differences are analysed in terms of texture and microstructure and some conclusions concerning the growth are drawn. On LAO, the nucleation is probably epitaxial and the anisotropy of the growth inhibits the transformation into Hg-1223 while some interfacial contribution expected to occur on MgO makes this transformation easier.