Development of buffer layers on 30mm wide textured metal substrates for REBCO coated conductors

ABSTRACTThe recent achievements of critical current densities in excess of 1MA/cm2 at 77K in YBCO films deposited over appropriate bi-axially textured buffer layers/metal substrates have stimulated interest in the potential future applications of coated conductors at liquid nitrogen temperature and high magnetic fields, which are called as the next/second generation tape conductors. Several different processes for obtaining the bi-axially textured buffer layers/metal substrates as well as thicker film deposition processes and non-vacuum processes are reviewed. This paper reviews the research goals of the project including the recent development of the related research by individual research group in Japan.

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Engineered oxide thin films as 100% lattice match buffer layers for YBCO coated conductors

Solid-State Electronics ◽

10.1016/s0038-1101(03)00192-8 ◽

2003 ◽

Vol 47 (12) ◽

pp. 2171-2175 ◽

Cited By ~ 17

Author(s):

Y. Akin ◽

Z.K. Heiba ◽

W. Sigmund ◽

Y.S. Hascicek

Keyword(s):

Thin Films ◽

Coated Conductors ◽

Buffer Layers ◽

Oxide Thin Films ◽

Lattice Match ◽

Ybco Coated Conductors

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Preparation and X-ray characterization of the mixed oxides (Gd1−xREx)2O3; (RE = Ho, Yb and Y) as powder and thin films buffer layers for YBCO coated conductors

Acta Crystallographica Section A Foundations of Crystallography ◽

10.1107/s0108767307095785 ◽

2007 ◽

Vol 63 (a1) ◽

pp. s186-s186

Author(s):

Z. A. Heiba ◽

L. Arda

Keyword(s):

Thin Films ◽

Mixed Oxides ◽

Coated Conductors ◽

Buffer Layers ◽

X Ray ◽

Ybco Coated Conductors

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Deposition of rare earth tantalate buffers on textured Ni-W substrates for YBCO coated conductor using chemical solution deposition approach

Journal of Materials Research ◽

10.1557/jmr.2006.0099 ◽

2006 ◽

Vol 21 (3) ◽

pp. 767-773 ◽

Cited By ~ 8

Author(s):

M.S. Bhuiyan ◽

M. Paranthaman ◽

A. Goyal ◽

L. Heatherly ◽

D.B. Beach

Keyword(s):

Rare Earth ◽

Chemical Solution Deposition ◽

Precursor Solution ◽

Coated Conductors ◽

Buffer Layers ◽

Chemical Solution ◽

Solution Deposition ◽

Force Microscopy ◽

Atomic Force ◽

Ybco Coated Conductors

Epitaxial films of rare-earth (RE = La, Ce, Eu, and Gd) tantalates, RE3TaO7 with pyrochlore structures were grown on biaxially textured nickel-3 at.% tungsten (Ni-W) substrates using chemical solution deposition (CSD) process. Precursor solution of 0.3∼0.4 M concentration of total cations were spin coated on to short samples of Ni-W substrates and the films were crystallized at 1050∼1100 °C in a gas mixture of Ar- 4% H2 for 15 to 60 min. X-ray studies show that the films of pyrochlore RE tantalate films are highly textured with cube-on-cube epitaxy. Improved texture was observed in case of lanthanum tantalate (La3TaO7) film grown on Ni-W substrates. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) investigations of RE3TaO7 films reveal a fairly dense and smooth microstructure without cracks and porosity. The rare-earth tantalate layers may be potentially used as buffer layers for YBa2Cu3O7-δ (YBCO) coated conductors.

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Inclined Substrate Deposition by Evaporation of Magnesium Oxide for Coated Conductors

MRS Proceedings ◽

10.1557/proc-585-35 ◽

1999 ◽

Vol 585 ◽

Cited By ~ 17

Author(s):

Markus Bauer ◽

Ralf Metzger ◽

Robert Semerad ◽

Paul Berberich ◽

Helmut Kinder

Keyword(s):

Electron Microscopy ◽

Coated Conductors ◽

The Other ◽

Buffer Layers ◽

Columnar Growth ◽

Initial Momentum ◽

3D Monte Carlo ◽

Deposition Direction ◽

Angle Deposition ◽

Scanning Electron

AbstractBiaxially textured MgO buffer layers were deposited on metal substrates using “inclined substrate deposition” (ISD). The influence of the substrate inclination angle, deposition rate, and film thickness on the texture is shown. Scanning electron microscopy reveals columnar growth. We developed a growth model to explain the texturing. To test this model we have carried out 3D Monte-Carlo simulations. We find that the preferred orientation arises from mutual shadowing of the columns and directional surface diffusion due to their initial momentum.YBa2Cu3O7 (YBCO) films deposited on the ISD buffer layers are highly textured. The ab-planes of the YBCO are tilted with respect to the surface by typically 25° towards the direction of MgO vapor incidence. Therefore, the critical current density jc is anisotropic with up to 8 × 105 MA/cm2 in one direction and 4 × 105 MA/cm2 in the other. For tape coating the MgO deposition direction can be chosen so that the high jc is along the tape.

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The microstructure of continuously processed Yba2Cu3Oy coated conductors with underlying CeO2 and ion-beam-assisted yttria-stabilized zirconia buffer layers

Journal of Materials Research ◽

10.1557/jmr.2000.0158 ◽

2000 ◽

Vol 15 (5) ◽

pp. 1110-1119 ◽

Cited By ~ 56

Author(s):

T. G. Holesinger ◽

S. R. Foltyn ◽

P. N. Arendt ◽

H. Kung ◽

Q. X. Jia ◽

...

Keyword(s):

Interfacial Reaction ◽

Ion Beam ◽

Misfit Strain ◽

Critical Currents ◽

Coated Conductors ◽

Yttria Stabilized Zirconia ◽

Buffer Layers ◽

Inconel 625 ◽

Microstructural Development ◽

Stabilized Zirconia

The microstructural development of YBa2Cu3Oy (Y-123) coated conductors based on the ion-beam-assisted deposition (IBAD) of yttria-stabilized zirconia (YSZ) to produce a biaxially textured template is presented. The architecture of the conductors was Y-123/CeO2/IBAD YSZ/Inconel 625. A continuous and passivating Cr2O3 layer forms between the YSZ layer and the Inconel substrate. CeO2 and Y-123 are closely lattice-matched, and misfit strain is accommodated at the YSZ/CeO2 interface. Localized reactions between the Y-123 film and the CeO2 buffer layer result in the formation of BaCeO3, YCuO2, and CuO. The positive volume change that occurs from the interfacial reaction may act as a kinetic barrier that limits the extent of the reaction. Excess copper and yttrium generated by the interfacial reaction appear to diffuse along grain boundaries and intercalate into Y-123 grains as single layers of the Y-247, Y-248, or Y-224 phases. The interfacial reactions do not preclude the attainment of high critical currents (Ic) and current densities (Jc) in these films nor do they affect to any appreciable extent the nucleation and alignment of the Y-123 film.

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