Raman Characterization of Doped 3C-SiC/Si for Different Silicon Substrates and C/Si Ratios

Raman microscopy has been used to study transport properties in hetero-epitaxial 3C-SiC/Si thin films. By an accurate analysis of the Longitudinal Optic phonon-plasmon coupled (LOPC) modes in n-type doped 3C-SiC films, free carrier density and mobility has been determined. A study of doped 3C-SiC reveals a strong relationship between the calculated free carrier density and both the C/Si ratio used during the epitaxial process and Silicon substrates orientation on which 3C-SiC thin films were grown (maintaining the N2 gas flow rate). The free carrier density obtained is in the range between 5x1016 cm-3 and 4x1018 cm-3. Epitaxial films grown on (111) Si substrates show a higher free carrier density and a lower dependence on C/Si ratios as compared to films grown on (100) Si substrates.

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Extraction of free carrier density and mobility from the optical transmission data of tin-doped indium oxide thin films

Materials Letters ◽

10.1016/0167-577x(95)00008-9 ◽

1995 ◽

Vol 23 (1-3) ◽

pp. 73-78 ◽

Cited By ~ 10

Author(s):

I.A. Rauf

Keyword(s):

Thin Films ◽

Indium Oxide ◽

Carrier Density ◽

Optical Transmission ◽

Free Carrier ◽

Oxide Thin Films ◽

Free Carrier Density ◽

Transmission Data

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Active Terahertz near-field probes for high-resolution free-carrier density imaging applications

2012 37th International Conference on Infrared, Millimeter, and Terahertz Waves ◽

10.1109/irmmw-thz.2012.6380311 ◽

2012 ◽

Cited By ~ 2

Author(s):

Michael Nagel ◽

Ali Safiei ◽

Tobias Pletzer ◽

Heinrich Kurz

Keyword(s):

High Resolution ◽

Carrier Density ◽

Near Field ◽

Free Carrier ◽

Free Carrier Density

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Magnetic Coupling in La0.7Ca0.3MnO3/YBa2Cu3O7/La0.7Ca0.3MnO3 Trilayers

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.289-292.303 ◽

2009 ◽

Vol 289-292 ◽

pp. 303-309

Author(s):

N.M. Nemes ◽

C. Visani ◽

J. Garcia-Barriocanal ◽

F.Y. Bruno ◽

Z. Sefrioui ◽

...

Keyword(s):

Magnetic Field ◽

High Temperature ◽

Carrier Density ◽

High Temperature Superconductor ◽

Hysteresis Loops ◽

Magnetic Coupling ◽

Oxygen Depletion ◽

Free Carrier ◽

Half Metallic ◽

Free Carrier Density

We report on the interplay between ferromagnetism and superconductivity in trilayers La0.7Ca0.3MnO3/YBa2Cu3O7/La0.7Ca0.3MnO3 made of half metallic manganite and high temperature superconductor cuprate. Samples with a fully oxygenated cuprate show a magnetic field interval where the magnetizations of the manganite are aligned antiparallel. A considerable magnetoresistance accompanies the switching between magnetization configurations (parallel vs. antiparallel) of the manganite moments. Suppression of the free carrier density of the cuprate which occurs upon oxygen depletion, results in deep modifications in the shape of the normal state hysteresis loops indicating that there may be a magnetic coupling mediated by free carrier density of the cuprate. This result outlines the importance of quasiparticle transmission in the interplay between ferromagnetism and superconductivity in this kind of samples.

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Thermographic imaging of free carrier density in silicon for solar cells

Quantitative InfraRed Thermography Journal ◽

10.3166/qirt.1.89-98 ◽

2004 ◽

Vol 1 (1) ◽

pp. 89-98

Author(s):

Martin C. Schubert ◽

Jörg Isenberg ◽

Stephan Riepe ◽

Wilhelm Warta

Keyword(s):

Solar Cells ◽

Carrier Density ◽

Free Carrier ◽

Free Carrier Density ◽

Thermographic Imaging

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In‐Situ Fabrication of YBa2Cu3O7‐x Superconducting Thin Films Directly on Silicon Substrates with Tc0 > 77K

MRS Proceedings ◽

10.1557/proc-169-481 ◽

1989 ◽

Vol 169 ◽

Author(s):

C. B. Lee ◽

R. K. Singh ◽

S. Sharan ◽

A. K. Singh ◽

P. Tiwari ◽

...

Keyword(s):

Thin Films ◽

Laser Pulses ◽

Superconducting Film ◽

Laser Evaporation ◽

Silicon Substrates ◽

Superconducting Thin Films ◽

Si Substrates ◽

In Situ Fabrication ◽

Substrate Temperatures

AbstractWe report in‐situ fabrication of c‐axis textured YBa2Cu3O7‐x superconducting thin films with Tco > 77K on unbuffered silicon substrates by the biased pulsed laser evaporation (PLE) technique in the temperature range of 550‐650°C. At substrate temperatures below 550°C, no c‐axis texturing of the superconducting film was observed. The YBa2Cu3O7‐x superconducting films were fabricated by ablating a bulk YBa2Cu3O7 target by a XeCl excimer laser (λ = 308 nm, τ = 45 × 10‐9 sec) in a chamber maintained at an oxygen pressure of 0.2 torr . The thickness of the films was varied from 0.3 to 0.5 nm depending on the number of laser pulses. Extensive diffusion was observed in thin films deposited at substrate temperatures above 550°C. However, microstructurally, with increase in the substrate temperature the films exhibited larger grain size and greater degree of c‐axis texturing (measured by the ratio of the (005) and (110) X‐ray diffraction peaks). This was found to give rise to better superconducting properties with Tco exceeding 77 K for YBa2Cu3O7‐x films deposited on Si substrates at 650°C.

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