Epitaxial and Smooth Films of a -Axis YBa ₂ Cu ₃ O ₇

Abstract

YBa(2)Cu(3)O(7) films have been grown epitaxially on SrTiO(3) (100) and LaAlO(3) (100) substrates with nearly pure a-axis orientation and with transition temperature T(c) (R = 0) of 85 K. A unique feature of these films is their smooth surface. These smooth surfaces enable the growth of short-period superlattices with well-defined modulations. The films are untwinned and the grains grow with their c-axis along one of two perpendicular directions on the substrate ([100] or [010]). The fabrication of sandwich-type Josephson junctions with good characteristics may now be possible because unlike c-axis-oriented films, the superconducting coherence length of these smooth films is appreciably large perpendicular to their surfaces.

Improved properties of Pulsed Laser Deposited YBaCuO on NdGaO 3 using CeO 2 template layers

“…From these data we can conclude that the films grown on NGO at a 'standard' deposition temperature consist of almost 90% of u-axis oriented YBCO. This also explains the reduced T,, of these films [3].…”

Growth, Morphology and Superconductivity of Epitaxial (RE)1Ba2Cu3O7-δFilms on SrTiO3and NdGaO3Substrates

“…8. Similar to (001)YBCO films, a mosaic pattern of domains is formed on (100)STO due to non-preferential alignment of the [001]YBCO direction [18]. Full in-plane coherence may be realized for (100)/(010)YBCO films on (110)NGO by ordering the [001]YBCO axis parallel and normal to the [001]NGO axis, associated with an rms-roughness of 1 nm [9].…”

The Controlled Synthesis of Metastable Oxides Utilizing Epitaxy and Epitaxial Stabilization

“…6), and the growth conditions is a key advantage of epitaxial growth. 172,[247][248][249][250][251][252][253] Orientation control is vital to the preparation of samples suitable for establishing the intrinsic properties of materials, especially those that cannot be prepared as bulk single crystals due to their metastability, high melting temperatures, or phase transitions that occur on cooling. When it comes to applications, techniques that can improve the functional properties of oxide films by controlling film texture through epitaxial growth on a grain-by-grain basis (local epitaxy) are also utilized, e.g., ion-beam-assisted deposition 254,255 and rolling-assisted biaxially textured substrates 256,257 for the growth of YBa 2 Cu 3 O 7 superconducting cables 258 as well as Pb(Zr,Ti)O 3 in FeRAMs.…”