Superconducting characteristics and the thermal stability of tungsten-based amorphous thin films

Superconducting characteristics and the thermal stability of sputtered, tungsten-based, amorphous thin films are investigated. Electronic properties and crystalline structures are analyzed as a function of the metalloid content in the films. It is well known that the superconducting Tc of a bulk crystalline tungsten is 0.01 K, which is one of the lowest transition temperatures among the superconducting metals. We have found that the W film containing 5 to 70 at. % metalloids exhibits a great enhancement in Tc. In the region of 15 to 35 at. % metalloids, the Tc shows the maximum of 5.0 K, and the transition from normal to superconducting state occurs very sharply. SEM observation together with x-ray diffraction analysis indicates that these films are amorphous in structure. The electrical resistivity is about 150 μΩ-cm, and shows little temperature dependence from Tc to 300 K. In addition, the W–Si amorphous superconductor is thermally very stable after annealing at 700 °C, but the W–Ge amorphous alloy crystallizes at 600 °C.

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Thermal Stability of Amorphous Ni-Nb Thin Films for Use as Diffusion Barriers

MRS Proceedings ◽

10.1557/proc-108-47 ◽

1987 ◽

Vol 108 ◽

Author(s):

S. N. Farrens ◽

J. H. Perepezko ◽

B. L. Doyle ◽

S. R. Lee

Keyword(s):

Thin Films ◽

Thermal Stability ◽

X Ray Diffraction ◽

Free Standing ◽

X Ray ◽

Amorphous Thin Films ◽

Si Substrates ◽

Sputter Deposited ◽

Film Substrate ◽

Thermal Stability Of

ABSTRACTThe interdiffusion and crystallization reactions between amorphous Ni-Nb alloy films and Si substrates and several overlayer metals have been monitored by x-ray diffraction and high resolution Rutherford backscattering spectroscopy. Free standing amorphous thin films of Ni-Nb alloys crystallize in one hour at temperatures between 600–625 °C and show little dependence of the crystallization temperature, Tx, on composition over the range from 30–80 at.% Ni. However, in films that are sputter deposited onto Si substrates Tx tends to increase with increasing Nb composition. Ni60Nb40 samples without overlayers crystallize at 650–700 °C. Enhancement of the thermal stability to 700–750 °C is achieved with a Nb overlayer. In contrast, a Ni overlayer can reduce Tx to 450 °C. At the film/substrate interface silicide formation reactions with Ni from the film contribute to a destabilization of the amorphous alloy. The modification of Tx with Ni, Nb, and other overlayers appears to be related to changes in the reaction kinetics associated with penetration of the overlayer into the film.

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Syntheses, Crystal Structures and Thermal Stability of Co(II) and Zn(II) Complexes with Ethyl Carbazate

Zeitschrift für Naturforschung B ◽

10.1515/znb-2005-0505 ◽

2005 ◽

Vol 60 (5) ◽

pp. 505-510 ◽

Cited By ~ 12

Author(s):

Tong-Lai Zhang ◽

Jiang-Chuang Song ◽

Jian-Guo Zhang ◽

Gui-Xia Ma ◽

Kai-Bei Yu

Keyword(s):

Thermal Stability ◽

Aqueous Solutions ◽

Diffraction Analysis ◽

Single Crystals ◽

Slow Evaporation ◽

X Ray Diffraction ◽

Element Analysis ◽

Thermal Stabilities ◽

X Ray ◽

Thermal Stability Of

Cobalt(II) and zinc(II) complexes of ethyl carbazate (ECZ), [Co(ECZ)3](NO3)2 and [Zn(ECZ)3] (NO3)2, were synthesized. Single crystals of these two compounds were grown from aqueous solutions using a slow evaporation method. Their structures have been determined by X-ray diffraction analysis. Both of them are monoclinic with space group P21/n. The complexes are further characterized by element analysis and IR measurements. Their thermal stabilities are studied by using TG-DTG, DSC techniques. When heated to 350 °C, only metal oxide was left for both complexes.

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Anomalously high density and thermal stability of nanotwins in Ni(W) thin films: Quantitative analysis by x-ray diffraction

Journal of Materials Research ◽

10.1557/jmr.2014.202 ◽

2014 ◽

Vol 29 (15) ◽

pp. 1642-1655 ◽

Cited By ~ 6

Author(s):

S.J.B. Kurz ◽

A. Leineweber ◽

E.J. Mittemeijer

Keyword(s):

Thin Films ◽

Thermal Stability ◽

Quantitative Analysis ◽

High Density ◽

X Ray Diffraction ◽

X Ray ◽

Image Position ◽

Thermal Stability Of

Abstract

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Effect of C16TMA contents on the thermal stability of organo-bentonites: In situ X-ray diffraction analysis

Thermochimica Acta ◽

10.1016/j.tca.2012.09.038 ◽

2013 ◽

Vol 551 ◽

pp. 7-13 ◽

Cited By ~ 12

Author(s):

Fethi Kooli

Keyword(s):

Thermal Stability ◽

Diffraction Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Thermal Stability Of

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Improvement of Thermal Stability of ZrB2/Si3N4 Coatings as High-Temperature Solar Selective Absorbers

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.521.581 ◽

2014 ◽

Vol 521 ◽

pp. 581-585

Author(s):

Yao Ming Sun ◽

Xiu Di Xiao ◽

Guan Qi Chai ◽

Gang Xu ◽

Bin Xiong ◽

...

Keyword(s):

Thin Films ◽

Thermal Stability ◽

High Temperature ◽

Substrate Temperature ◽

Bias Voltage ◽

X Ray Diffraction ◽

Substrate Bias Voltage ◽

X Ray ◽

Deposition Parameters ◽

Thermal Stability Of

ZrB2 thin films were prepared by DC magnetron sputtering technique. The microstructure, thermal stability and optical properties of thin films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and spectrophotometer. The compactness of ZrB2 thin films was studied to improve the thermal stability by optimizing the deposition parameters. The compactness and thermal stability of the coatings were improved with the increase of substrate temperature. However, these properties of the coatings were enhanced firstly and then weakened with the increase of substrate bias voltage. The selectivity of sample deposited at high substrate temperature and suitable bias voltage degraded slightly after annealing at 500 °C/100 h in air. This provided a new way to improve the thermal stability of high-temperature solar selective absorber.

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Comparison of Thermal Stability of Epitaxially Grown (La0.5Sr0.5)CoO3 and (La0.6Sr0.4)MnO3 Thin Films Deposited on Si Substrate

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.445.160 ◽

2010 ◽

Vol 445 ◽

pp. 160-163

Author(s):

Shigeki Sawamura ◽

Naonori Sakamoto ◽

De Sheng Fu ◽

Kazuo Shinozaki ◽

Hisao Suzuki ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Thermal Stability ◽

High Resistivity ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Post Annealing ◽

Thermal Stability Of

Thermal stability of bottom electrode thin films (La0.5Sr0.5)CoO3 (LSCO) and (La0.6Sr0.4)MnO3 (LSMO) were investigated. The crystallization and surface morphology of the heterostructure were characterized using x-ray diffraction and atomic force microscopy. Resistivity of the LSCO thin film was 25 cm. However, the resistivity of LSCO thin film increases sharply with annealing temperature. The LSMO thin film has high resistivity (100 mcm). The film does not decompose after thermal processing at 900 °C. To confirm thermal stability, we examined the effect of post annealing at various temperatures on the morphology and resistivity. Results showed that LSMO has higher thermal stability than that of LSCO.

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Formation and Thermal Stability of Nd0.32Y0.68Si1.7 Layers Formed by Channeled Ion Beam Synthesis

MRS Proceedings ◽

10.1557/proc-514-191 ◽

1998 ◽

Vol 514 ◽

Cited By ~ 1

Author(s):

M. F. Wu ◽

A. Vantomne ◽

S. Hogg ◽

H. Pattyn ◽

G. Langouche ◽

...

Keyword(s):

Thermal Stability ◽

Ion Beam ◽

Hexagonal Structure ◽

Orthorhombic Structure ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Good Crystalline Quality ◽

Ion Beam Synthesis ◽

Thermal Stability Of

ABSTRACTThe Nd-disilicide, which exists only in a tetragonal or an orthorhombic structure, cannot be grown epitaxially on a Si(111) substrate. However, by adding Y and using channeled ion beam synthesis, hexagonal Nd0.32Y0.68Si1.7 epilayers with lattice constant of aepi = 0.3915 nm and cepi = 0.4152 nm and with good crystalline quality (χmin of Nd and Y is 3.5% and 4.3 % respectively) are formed in a Si(111) substrate. This shows that the addition of Y to the Nd-Si system forces the latter into a hexagonal structure. The epilayer is stable up to 950 °C; annealing at 1000 °C results in partial transformation into other phases. The formation, the structure and the thermal stability of this ternary silicide have been studied using Rutherford backscattering/channeling, x-ray diffraction and transmission electron microscopy.

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Study of Thermal Behaviour of EPDM/SBR Blends and Carbon Nanocoatings Deposited by Sputtering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.875.116 ◽

2021 ◽

Vol 875 ◽

pp. 116-120

Author(s):

Muhammad Alamgir ◽

Faizan Ali Ghauri ◽

Waheed Qamar Khan ◽

Sajawal Rasheed ◽

Muhammad Sarfraz Nawaz ◽

...

Keyword(s):

Thermal Stability ◽

Weight Loss ◽

Thermogravimetric Analysis ◽

Thermal Behavior ◽

Thermal Behaviour ◽

X Ray Diffraction ◽

X Ray ◽

Thermal Stability Of

In this study, the effect of SBR concentration (10 Phr, 20 Phr & 30 Phr ) on the thermal behavior of EPDM/SBR blends was studied. Thermogravimetric analysis (TGA) was used to check weight loss of samples as function of temperature by heating upto 600°C. X-ray diffraction (XRD) was performed to determine quality and % crystallinity of the elastomer blends. It was seen that % crystallinity improved with an increase in the content of SBR in EPDM/SBR blends. TGA revealed that the thermal stability of EPDM/SBR blends has improved by 17% than neat EPDM. Carbon nano-coatings produced by sputtering have no beneficial influence on thermal behaviour of elastomers.

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