Thermoelectric properties of epitaxial and topotaxial NaxCoO2 thin films

ABSTRACTWe report structural, electrical, and thermopower properties of epitaxial and topotaxial NaxCoO2 thin films on (0001) sapphire substrate. Topotaxial NaxCoO2 films were prepared by converting an epitaxial Co3O4 film to NaxCoO2 by annealing in Na vapor and epitaxial NaxCoO2 films were obtained by pulsed laser deposition. All the films are c-axis oriented. For topotaxial films, annealing in different Na vapor pressures resulted in films with different Na concentrations, which showed distinct transport properties. For directly deposited epitaxial films by pulsed laser deposition, deposition parameters are found to control the Na concentration and hence the film properties. The largest thermoelectric power of the samples made by different methods is found to be similar in the range of 70-100 μV/K at room temperature

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Processing by Pulsed Laser Deposition and Structural, Morphological and Chemical Characterization of Bi-Pb-Sr-Ca-Cu-O and Bi-Pb-Sb-Sr-Ca-Cu-O Thin Films

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.75.202 ◽

2010 ◽

Vol 75 ◽

pp. 202-207

Author(s):

Victor Ríos ◽

Elvia Díaz-Valdés ◽

Jorge Ricardo Aguilar ◽

T.G. Kryshtab ◽

Ciro Falcony

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Room Temperature ◽

Pulsed Laser ◽

Chemical Characterization ◽

Laser Deposition ◽

Nominal Composition ◽

Deposition Parameters ◽

The Relationship

Bi-Pb-Sr-Ca-Cu-O (BPSCCO) and Bi-Pb-Sb-Sr-Ca-Cu-O (BPSSCCO) thin films were grown on MgO single crystal substrates by pulsed laser deposition. The deposition was carried out at room temperature during 90 minutes. A Nd:YAG excimer laser ( = 355 nm) with a 2 J/pulse energy density operated at 30 Hz was used. The distance between the target and substrate was kept constant at 4,5 cm. Nominal composition of the targets was Bi1,6Pb0,4Sr2Ca2Cu3O and Bi1,6Pb0,4Sb0,1Sr2Ca2Cu3OSuperconducting targets were prepared following a state solid reaction. As-grown films were annealed at different conditions. As-grown and annealed films were characterized by XRD, FTIR, and SEM. The films were prepared applying an experimental design. The relationship among deposition parameters and their effect on the formation of superconducting Bi-system crystalline phases was studied.

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The Optimization of Niobium Diselenide Thin Films Through Control of Pulsed Laser Deposition Parameters

MRS Proceedings ◽

10.1557/proc-285-539 ◽

1992 ◽

Vol 285 ◽

Cited By ~ 2

Author(s):

Allan E. Day ◽

Samuel J.P. Laube ◽

M.S. Donley ◽

J.S. Zabinski

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Optimal Growth ◽

Growth Conditions ◽

Laser Deposition ◽

Film Properties ◽

Niobium Diselenide ◽

Deposition Parameters ◽

And Control

ABSTRACTNiobium diselenide has potential for use as a conductive lubricant, but to achieve the optimal properties of low friction coefficient, high conductivity and oxidation resistance, the SeJNb ratio and crystallinity must be carefully controlled. It has been shown that Pulsed Laser Deposition (PLD) permits the required degree of control, even over films with complex stoichiometries. (4–8). In this study, PLD was used to grow stoichiometric, crystalline thin films of niobium diselenide and to study the effects of laser deposition parameters on film properties. Film chemistry and crystallinity were evaluated using XPS, RBS, and glancingangle XRD. Friction and wear measurements were taken on a ball-on-flat tribometer. The deposition apparatus incorporates a fully computerized data acquisition and control system that facilitated the correlation of the laser deposition parameters to film properties. This study has shown that film chemistry could be changed from substoichiometric to superstoichiometric and crystallinity varied between amorphous to highly crystalline by appropriate choice of PLD parameters. The property correlations and acquisition system that permitted the identification of the optimal growth conditions will be described.

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Room-temperature ferromagnetism in (Ga, Mn)N thin films grown by pulsed laser deposition

Superlattices and Microstructures ◽

10.1016/j.spmi.2004.09.004 ◽

2004 ◽

Vol 36 (4-6) ◽

pp. 403-408 ◽

Cited By ~ 9

Author(s):

D. O’Mahony ◽

F. McGee ◽

M. Venkatesan ◽

J.G. Lunney ◽

J.M.D. Coey

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Pulsed Laser ◽

Laser Deposition

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Influence of the deposition parameters on the structural and transport properties of YBaCuO thin films prepared by pulsed laser deposition

Applied Surface Science ◽

10.1016/s0169-4332(97)00697-1 ◽

1998 ◽

Vol 127-129 ◽

pp. 520-524 ◽

Cited By ~ 10

Author(s):

S. Duhalde ◽

A. Lamagna ◽

M. Villafuerte ◽

A. Schwartzman ◽

L. Correra ◽

...

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Transport Properties ◽

Pulsed Laser ◽

Laser Deposition ◽

Deposition Parameters

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Luminescent Characteristics of Pulsed Laser Deposited Epitaxial Eu-Doped Y2O3 Films

MRS Proceedings ◽

10.1557/proc-574-11 ◽

1999 ◽

Vol 574 ◽

Author(s):

D. Kumar ◽

K. G. Cho ◽

Zhang Chen ◽

V. Craciun ◽

P. H. Holloway ◽

...

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Epitaxial Growth ◽

Yttrium Oxide ◽

Lattice Mismatch ◽

Pulsed Laser ◽

Laser Deposition ◽

Deposition Technique ◽

Deposition Parameters

AbstractThe growth, structural and cathodoluminescent (CL) properties of europium activated yttrium oxide (Eu:Y2O3) thin films are reported. The Eu:Y2O3 films were grown in-situ using a pulsed laser deposition technique. Our results show that Eu:Y2O3 films can grow epitaxially on (100) LaAlO3 substrates under optimized deposition parameters. The epitaxial growth of Eu:Y2O3 films on LaAlO3, which has a lattice mismatch of ∼ 60 %, is explained by matching of the atom positions in the lattices of the film and the substrate after a rotation. CL data from these films are consistent with highly crystalline Eu:Y2O3 films with an intense CL emission at 611 nm.

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