Epitaxial growth and transport properties of Nb-doped SrTiO 3 thin films

Takahashi, Kei; Jaccard, D.; Shibuya, Keisuke; Ohnishi, T.; Lippmaa, Mikk; Triscone, Jean‐Marc

doi:10.1117/12.616888

Cited by 3 publications

(2 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, much work is needed to determine whether a temperature dependent Hall factor or two (or multi-) carrier conduction dominates the temperature dependent Hall coefficient, because we have scarce evidence to specify the expression of Hall factor B as a function of temperature, and to testify the existence of two (or multi-) carriers. Takahashi et al [30] reported the temperature dependent Hall coefficient in Nb-doped SrTiO 3 thin films and he supported the argument that temperature dependent Hall coefficient is related to the existence of two types of carriers in doped SrTiO 3 .…”

Section: Hall Measurementmentioning

confidence: 79%

Effect of oxygen content on the transport properties of LaTiO_3+β/2thin films

Wang

et al. 2006

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The structural and transport properties of LaTiO(3+β/2) epitaxial thin films, grown at different oxygen pressures ranging from 6.6 × 10(-4) to 5 Pa, have been investigated. X-ray diffraction peaks of the films shift to lower angles with increasing oxygen pressure, indicative of a variation of the corresponding lattice spacing. All the films show T(2) dependence of resistivity over a large temperature range of ∼200 K, suggesting a band-filling-induced metallic Fermi-liquid behaviour. Upturns in resistivity have been revealed at low temperatures, which could be ascribed to the Anderson-localization effect caused by the cation vacancies. Furthermore, for the thin films grown at high oxygen pressures of 0.5 and 5 Pa, the dependence of resistivity on temperature shows a maximum at high temperatures. The maximum seems to support the argument that transition between t-orbital ordering and disordering plays an important role in dominating transport properties at high temperatures. Carrier density deduced from Hall coefficient increases with the decrease of oxygen content, and shows strong temperature dependence. From the experimental data, it can be asserted that in the LaTiO(3+β/2) thin films, besides the band filling effect, localization or disorder caused by La and Ti vacancy effects controls the unique transport properties.

show abstract

Section: Hall Measurementmentioning

confidence: 79%

Effect of oxygen content on the transport properties of LaTiO_3+β/2thin films

Wang

et al. 2006

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…The electrical resistivity of the Nb-STO layer deposited at 800 °C was estimated to be approximately 10 −3 Ω•cm at approximately 77 K. The Nb-STO films deposited by PLD were previously reported in Ref. 18. The Nb-STO film was deposited at a very high temperature of 1300 °C and a low oxygen pressure of 2 × 10 −6 Torr, and then annealed to reoxidize.…”

Section: Nb-sto Conductive Buffer Layers On Textured Copper Tapesmentioning

confidence: 94%

Possibility of material cost reduction toward development of low-cost second-generation superconducting wires

Ichinose

Horii

Doi

2017

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

Two approaches to reducing the material cost of second-generation superconducting wires are proposed in this paper: (1) instead of the electrical stabilizing layers of silver and copper presently used on the superconducting layer, a Nb-doped SrTiO3 conductive buffer layer and cube-textured Cu are proposed as an advanced architecture, and (2) the use of an electromagnetic (EM) steel tape as a metal substrate of coated conductors in a conventional architecture. In structures fabricated without using electrical stabilizing layers on the superconducting layer, the critical current density achieved at 77 K in a self-field was approximately 2.6 MA/cm2. On the other hand, in the case of using EM steel tapes, although the critical current density was far from practical at the current stage, the biaxial alignment of YBa2Cu3Oy (YBCO) and buffer layers was realized without oxidation on the metal surface. In this study, the possibility of material cost reduction has been strongly indicated toward the development of low-cost second-generation superconducting wires in the near future.

show abstract

Thermoelectric properties of Nb-doped SrTiO₃ films prepared by co-sputtering

Kim

Duy

Lee

et al. 2020

Journal of Asian Ceramic Societies

View full text Add to dashboard Cite

SrTiO 3 (STO), a member of perovskite structure materials, exhibits a large thermoelectric figure of merit at high temperatures. Theoretically, its property can be significantly improved by niobium (Nb) dopant. So far, the synthesis method of Nb-doped STO and the evaluation of their thermoelectric properties at low temperatures have not been explored fully. Here, our development of highly Nb-doped STO films using the co-sputtering with STO and Nb targets at room temperature (298 K) is introduced. A rapid annealing process (30 min, at 1073 K) is applied to further crystallize these films. Through measurements at 300 ~ 600 K, a significant improvement of the thermoelectric performance of STO films upon 2% Nb-doping is observed. Particularly, the working temperature of Nb-doped STO begins at 350 K instead of 475 K of STO. The figure of merit of Nb-doped STO can reach 0.53 at 600 K. Through TEM-EDS and TOF-SIMS characterizations, the mechanism of Nb-doping effect on the STO properties is revealed and discussed in detail. Our doping method at room temperature is potential, as compared to other synthesis methods, regarding the uniform incorporation of Nb dopants in STO films. Overall, our work showed another way for further improvement of perovskite-based thermoelectric materials.

show abstract

Epitaxial growth and transport properties of Nb-doped SrTiO 3 thin films

Cited by 3 publications

References 17 publications

Effect of oxygen content on the transport properties of LaTiO_3+β/2thin films

Effect of oxygen content on the transport properties of LaTiO_3+β/2thin films

Possibility of material cost reduction toward development of low-cost second-generation superconducting wires

Thermoelectric properties of Nb-doped SrTiO₃ films prepared by co-sputtering

Contact Info

Product

Resources

About

Epitaxial growth and transport properties of Nb-doped SrTiO 3 thin films

Cited by 3 publications

References 17 publications

Effect of oxygen content on the transport properties of LaTiO3+β/2thin films

Effect of oxygen content on the transport properties of LaTiO3+β/2thin films

Possibility of material cost reduction toward development of low-cost second-generation superconducting wires

Thermoelectric properties of Nb-doped SrTiO3 films prepared by co-sputtering

Contact Info

Product

Resources

About

Effect of oxygen content on the transport properties of LaTiO_3+β/2thin films

Effect of oxygen content on the transport properties of LaTiO_3+β/2thin films

Thermoelectric properties of Nb-doped SrTiO₃ films prepared by co-sputtering