Formation of a p‐n junction in silicon carbide by aluminum doping at room temperature using a pulsed laser doping method

Pulsed laser deposition (PLD) is a novel technique for the deposition of tribological thin films. MoS2 is the archetypical solid lubricant material for aerospace applications. It provides a low coefficient of friction from cryogenic temperatures to about 350°C and can be used in ultra high vacuum environments. The TEM is ideally suited for studying the microstructural and tribo-chemical changes that occur during wear. The normal cross sectional TEM sample preparation method does not work well because the material’s lubricity causes the sandwich to separate. Walck et al. deposited MoS2 through a mesh mask which gave suitable results for as-deposited films, but the discontinuous nature of the film is unsuitable for wear-testing. To investigate wear-tested, room temperature (RT) PLD MoS2 films, the sample preparation technique of Heuer and Howitt was adapted.Two 300 run thick films were deposited on single crystal NaCl substrates. One was wear-tested on a ball-on-disk tribometer using a 30 gm load at 150 rpm for one minute, and subsequently coated with a heavy layer of evaporated gold.

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Direct-patterning of silicon carbide by nanosphere-assisted pulsed laser

International Congress on Applications of Lasers & Electro-Optics ◽

10.2351/1.5060598 ◽

2005 ◽

Author(s):

Arvind Battula ◽

Senthil Theppakuttai ◽

Shaochen Chen

Keyword(s):

Silicon Carbide ◽

Pulsed Laser ◽

Direct Patterning

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High thermal conductivity of pure dense SiC ceramics prepared via HTPVT

Functional Materials Letters ◽

10.1142/s1793604719500322 ◽

2019 ◽

Vol 12 (03) ◽

pp. 1950032 ◽

Cited By ~ 2

Author(s):

Yuchen Deng ◽

Yaming Zhang ◽

Nanlong Zhang ◽

Qiang Zhi ◽

Bo Wang ◽

...

Keyword(s):

Thermal Conductivity ◽

Silicon Carbide ◽

Grain Size ◽

Phase Composition ◽

Room Temperature ◽

Vapor Transport ◽

Physical Vapor Transport ◽

Growth Substrate ◽

Sic Ceramics ◽

Evolution Of Microstructure

Pure dense silicon carbide (SiC) ceramics were obtained via the high-temperature physical vapor transport (HTPVT) method using graphite paper as the growth substrate. The phase composition, the evolution of microstructure, the thermal diffusivity and thermal conductivity at RT to 200∘C were investigated. The obtained samples had a relative density of higher than 98.7% and a large grain size of 1[Formula: see text]mm, the samples also had a room-temperature thermal conductivity of [Formula: see text] and with the temperature increased to 200∘C, the thermal conductivity still maintained at [Formula: see text].

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Pressure-controlled preparation of nanocrystalline complex oxides using pulsed-laser ablation at room temperature

Applied Physics A ◽

10.1007/s00339-002-1666-3 ◽

2003 ◽

Vol 76 (4) ◽

pp. 641-643 ◽

Cited By ~ 12

Author(s):

J.W. Yoon ◽

T. Sasaki ◽

N. Koshizaki

Keyword(s):

Laser Ablation ◽

Room Temperature ◽

Pulsed Laser ◽

Pulsed Laser Ablation ◽

Complex Oxides ◽

Controlled Preparation ◽

Pressure Controlled

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Annealing Condition Effects on the Structural Properties of FePt Nanoparticles Embedded in MgO via Pulsed Laser Deposition

Nanomaterials ◽

10.3390/nano11010131 ◽

2021 ◽

Vol 11 (1) ◽

pp. 131

Author(s):

Tingting Xiao ◽

Qi Yang ◽

Jian Yu ◽

Zhengwei Xiong ◽

Weidong Wu

Keyword(s):

Pulsed Laser Deposition ◽

Room Temperature ◽

High Vacuum ◽

Pulsed Laser ◽

Annealing Process ◽

Ultra High Vacuum ◽

Laser Deposition ◽

Fept Nanoparticles ◽

Annealing Conditions ◽

Vacuum Atmosphere

FePt nanoparticles (NPs) were embedded into a single-crystal MgO host by pulsed laser deposition (PLD). It was found that its phase, microstructures and physical properties were strongly dependent on annealing conditions. Annealing induced a remarkable morphology variation in order to decrease its total free energy. H2/Ar (95% Ar + 5% H2) significantly improved the L10 ordering of FePt NPs, making magnetic coercivity reach 37 KOe at room temperature. However, the samples annealing at H2/Ar, O2, and vacuum all showed the presence of iron oxide even with the coverage of MgO. MgO matrix could restrain the particles’ coalescence effectively but can hardly avoid the oxidation of Fe since it is extremely sensitive to oxygen under the high-temperature annealing process. This study demonstrated that it is essential to anneal FePt in a high-purity reducing or ultra-high vacuum atmosphere in order to eliminate the influence of oxygen.

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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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