Enhancement in superconducting properties of Y-Ba-Cu-O thin films by post-annealing in an inert atmosphere

Here, Bi(Pb)-Sr-Ca-Cu-O thin films having superconducting properties have been fabricated using Nd-YAG pulsed laser ablation onto single-crystal MgO(100) substrates. The as-deposited film was found to be in an amorphous state. The crystalline structure appeared after the film was annealed in an oxygen environment. The XRD spectrum revealed epitaxial growth of BSCCO (2212) phase at annealing temperatures of 850°C, 860°C and 870°C. In the amorphous state, the microstructure of the films exhibited spherical clusters of various sizes. Upon annealing, plate-like and needle-like structures were observed. These structures fused into grains with a plate-like shape when the annealing temperature reached 870°C. This could be due to the diffusion and arrangement of the components that make up the 2212 phase at elevated temperature in an oxygen environment. The superconducting transition temperature, Tc, is highest for samples annealed at 870°C. The post-annealing procedures were carried out in the ablation chamber in order to minimize contamination.

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Superconducting Properties and Microstructures of ${\rm MgB}_{2}$ Thin Films Fabricated With the Precursor and Post-Annealing Method

IEEE Transactions on Applied Superconductivity ◽

10.1109/tasc.2009.2018281 ◽

2009 ◽

Vol 19 (3) ◽

pp. 2823-2826 ◽

Cited By ~ 2

Author(s):

A. Matsumoto ◽

K.-i. Takahashi ◽

M. Tachiki ◽

H. Kitaguchi ◽

H. Kumakura

Keyword(s):

Thin Films ◽

Superconducting Properties ◽

Post Annealing ◽

Annealing Method

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SUPERCONDUCTING PROPERTIES OF IRIDIUM THIN FILMS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19786274 ◽

1978 ◽

Vol 39 (C6) ◽

pp. C6-608-C6-609

Author(s):

L. B. Holdeman ◽

R. J. Soulen ◽

Jr ◽

T. F. Finnegan ◽

P. N. Peters

Keyword(s):

Thin Films ◽

Superconducting Properties

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Reactive Dual Magnetron Sputtering: A Fast Method for Preparing Stoichiometric Microcrystalline ZnWO4 Thin Films

Surfaces ◽

10.3390/surfaces4020013 ◽

2021 ◽

Vol 4 (2) ◽

pp. 106-114

Author(s):

Yannick Hermans ◽

Faraz Mehmood ◽

Kerstin Lakus-Wollny ◽

Jan P. Hofmann ◽

Thomas Mayer ◽

...

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Photoelectron Spectroscopy ◽

Fast Method ◽

X Ray Diffraction ◽

X Ray ◽

Glass Substrates ◽

Post Annealing ◽

Rf Signal ◽

First Time

Thin films of ZnWO4, a promising photocatalytic and scintillator material, were deposited for the first time using a reactive dual magnetron sputtering procedure. A ZnO target was operated using an RF signal, and a W target was operated using a DC signal. The power on the ZnO target was changed so that it would match the sputtering rate of the W target operated at 25 W. The effects of the process parameters were characterized using optical spectroscopy, X-ray diffraction, and scanning electron microscopy, including energy dispersive X-ray spectroscopy as well as X-ray photoelectron spectroscopy. It was found that stoichiometric microcrystalline ZnWO4 thin films could be obtained, by operating the ZnO target during the sputtering procedure at a power of 55 W and by post-annealing the resulting thin films for at least 10 h at 600 °C. As FTO coated glass substrates were used, annealing led as well to the incorporation of Na, resulting in n+ doped ZnWO4 thin films.

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Optimizing the Properties of La0.8Sr0.2CrO3 Thin Films through Post-Annealing for High-Temperature Sensing

Nanomaterials ◽

10.3390/nano11071802 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1802

Author(s):

Dan Liu ◽

Peng Shi ◽

Yantao Liu ◽

Yijun Zhang ◽

Bian Tian ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Annealing Temperature ◽

Rf Sputtering ◽

Maximum Size ◽

Cross Sectional ◽

Post Annealing ◽

Maximum Conductivity ◽

Different Temperatures ◽

Post Annealing Temperature

La0.8Sr0.2CrO3 (0.2LSCO) thin films were prepared via the RF sputtering method to fabricate thin-film thermocouples (TFTCs), and post-annealing processes were employed to optimize their properties to sense high temperatures. The XRD patterns of the 0.2LSCO thin films showed a pure phase, and their crystallinities increased with the post-annealing temperature from 800 °C to 1000 °C, while some impurity phases of Cr2O3 and SrCr2O7 were observed above 1000 °C. The surface images indicated that the grain size increased first and then decreased, and the maximum size was 0.71 μm at 1100 °C. The cross-sectional images showed that the thickness of the 0.2LSCO thin films decreased significantly above 1000 °C, which was mainly due to the evaporation of Sr2+ and Cr3+. At the same time, the maximum conductivity was achieved for the film annealed at 1000 °C, which was 6.25 × 10−2 S/cm. When the thin films post-annealed at different temperatures were coupled with Pt reference electrodes to form TFTCs, the trend of output voltage to first increase and then decrease was observed, and the maximum average Seebeck coefficient of 167.8 µV/°C was obtained for the 0.2LSCO thin film post-annealed at 1100 °C. Through post-annealing optimization, the best post-annealing temperature was 1000 °C, which made the 0.2LSCO thin film more stable to monitor the temperatures of turbine engines for a long period of time.

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Structural and optical properties of ZnO and Ni:ZnO thin films: the trace of post-annealing

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-020-05092-x ◽

2021 ◽

Author(s):

Mansoure Ilkhani ◽

Laya Dejam

Keyword(s):

Thin Films ◽

Optical Properties ◽

Structural And Optical Properties ◽

Post Annealing

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Strain-stabilized superconductivity

Nature Communications ◽

10.1038/s41467-020-20252-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

J. P. Ruf ◽

H. Paik ◽

N. J. Schreiber ◽

H. P. Nair ◽

L. Miao ◽

...

Keyword(s):

Thin Films ◽

Materials Science ◽

Condensed Matter ◽

Quantum States ◽

Low Energy ◽

Superconducting Transition ◽

Superconducting Properties ◽

Detailed Understanding ◽

Epitaxial Strain ◽

Promising Strategy

AbstractSuperconductivity is among the most fascinating and well-studied quantum states of matter. Despite over 100 years of research, a detailed understanding of how features of the normal-state electronic structure determine superconducting properties has remained elusive. For instance, the ability to deterministically enhance the superconducting transition temperature by design, rather than by serendipity, has been a long sought-after goal in condensed matter physics and materials science, but achieving this objective may require new tools, techniques and approaches. Here, we report the transmutation of a normal metal into a superconductor through the application of epitaxial strain. We demonstrate that synthesizing RuO2 thin films on (110)-oriented TiO2 substrates enhances the density of states near the Fermi level, which stabilizes superconductivity under strain, and suggests that a promising strategy to create new transition-metal superconductors is to apply judiciously chosen anisotropic strains that redistribute carriers within the low-energy manifold of d orbitals.

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