DISCHARGE CHARACTERISTICS OF THE MAGNETRON SYSTEM FOR SPUTTERING, DEPOSITION, AND NANOTECHNOLOGY APPLICATIONS

Magnetron sputtering is known for years as a powerful tool for coating deposition of cutting tools and machine parts. However the experimental measurements of the magnetron discharge parameters are still necessary to provide a consumer of the magnetron system with the reliable characteristics. A voltage-current relation is the most applied characteristic of the discharge, and it is described as the power low of a type U = U0 + aIn, where U and I are the voltage drop and the discharge current, respectively, and U0 and n are constant. First part of the research is dedicated to the experiments conducted in the magnetron setup provided with the titanium cathode in a vacuum chamber filled with argon or argon-nitrogen mixture, and the constants are determined for the particular geometry of the magnetron sputtering system. The obtained results can be used to choose the operation modes for the traditional applications of the magnetron discharge such as ion cleaning and heating of the non-magnetic workpieces arranged on the cathode, as well as for the sputtering deposition of the titanium and titanium nitride coatings on the surfaces of the workpieces located above the magnetron cathode. In the next part of the research the novel application of the magnetron for production of carbon nanostructures is considered. For the purpose, a layer of expanded graphite is arranged on the magnetron cathode, and the discharge is initiated in oxygen atmosphere. It was found that for the time interval of a few hours the discharge is described as a superposition of the typical magnetron glow with arc spot generation, and the intensity of the arcs is not decreased with time. At that, the arc initiation was accompanied with the formation of clusters of the graphite cathode. The process is explained in terms of the cathode spot generation at the interaction of the arc plasma with the non-melting material. This process can be beneficial for the development of the plasma reactors for the large-scale production of the carbon species at the low gas pressures suitable for the magnetron discharge operation. Thus, the magnetron sputtering systems provided with the expanded graphite cathode can be considered as the tool to grow carbon nanospecies in the arc discharge cathode spots.

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Carbon nanostructure growth: new application of magnetron discharge

Journal of Achievements of Materials and Manufacturing Engineering ◽

10.5604/01.3001.0015.5856 ◽

2021 ◽

Vol 109 (1) ◽

pp. 17-25

Author(s):

A. Breus ◽

S. Abashin ◽

O. Serdiuk

Keyword(s):

Carbon Nanostructures ◽

Large Scale ◽

Glow Discharge Plasma ◽

Scale Production ◽

Plasma Reactors ◽

Carbon Nanostructure ◽

Magnetron Discharge ◽

Sputtering Deposition ◽

High Productivity ◽

Race Track

Purpose: The application of a common magnetron discharge to the growth of carbon nanostructures is studied. The simplicity of the proposed technique can be beneficial for the development of new plasma reactors for large-scale production of carbon nanostructures. Design/methodology/approach: Graphite cathode was treated by carbon-containing powder accelerated by use of nozzle, and then aged in hydrogen. Superposition of glow and arc discharges was obtained, when putting the cathode under the negative biasing with respect to the walls of a vacuum chamber. The pulsed discharge was preserved through the whole time of treatment. This process was explained in terms of interaction of glow discharge plasma with a surface of the cathode made of non-melting material. Findings: The plasma treatment resulted in generation of the diverse nanostructures confirmed by SEM and TEM images. Spruce-like nanostructures and nanofibers are observed near the cathode edge where the plasma was less dense; a grass-like structure was grown in the area of “race-track”; net-like nanostructures are found among the nanofibers. These findings allow concluding about the possible implementation of the proposed method in industry. Research limitations/implications: The main limitation is conditioned by an explosive nature of nanostructure generation in arcs; thus, more elaborate design of the setup should be developed in order to collect the nanospecies in the following study. Practical implications: High-productivity plasma process of nanosynthesis was confirmed in this research. It can be used for possible manufacturing of field emitters, gas sensors, and supercapacitors. Originality/value: Synthesis of carbon nanostructures is conducted by use of a simple and well-known technique of magnetron sputtering deposition where a preliminary surface treatment is added to expand the production yield and diversity of the obtained nanostructures.

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Improved efficiency of liquid-phase shear exfoliation of expanded graphite with bifunctional additives of mica plates

Journal of Materials Chemistry A ◽

10.1039/d1ta07915h ◽

2021 ◽

Author(s):

Bin Liang ◽

Kangwei Liu ◽

Peng Liu ◽

Guangyao Zhao ◽

Weisheng Pan ◽

...

Keyword(s):

Liquid Phase ◽

Large Scale ◽

Expanded Graphite ◽

Scale Production ◽

Large Scale Production ◽

High Yields

Liquid-phase shear exfoliation (LPSE) has been a potential way of large-scale production of good-quality graphene. How to obtain few-layer (<10) graphene with large lateral sizes and high yields remains a...

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A Study of Manufacturing Processes of Composite Form-Stable Phase Change Materials Based on Ca(NO3)2–NaNO3 and Expanded Graphite

Materials ◽

10.3390/ma13235368 ◽

2020 ◽

Vol 13 (23) ◽

pp. 5368

Author(s):

Yunxiu Ren ◽

Chao Xu ◽

Tieying Wang ◽

Ziqian Tian ◽

Zhirong Liao

Keyword(s):

Large Scale ◽

Phase Change Materials ◽

Sintering Temperature ◽

Expanded Graphite ◽

Stable Phase ◽

Operating Parameters ◽

Scale Production ◽

Pressing Pressure ◽

Large Scale Production ◽

Melt Impregnation

The fabrication of form-stable phase change materials (FS-PCMs) usually involves four manufacturing processes: mixing, immersion, stabilization, and sintering. In each process, the operation parameters could affect the performance of the fabricated PCM composite. To gain an efficient and low-cost method for large-scale production of the molten salts/expanded graphite (EG) composite FS-PCMs, the effects of different operating parameters were investigated, including the stirring speed, evaporation temperature, melt-impregnation, cold-pressing pressure, and sintering temperature on the densification, microstructure, and thermophysical properties of the composite FS-PCMs. It was found that the microstructure, the morphology and durability, and the thermophysical properties such as thermal conductivity and specific heat enthalpy depended highly on the operating parameters. The following optimal operating parameters of the Ca(NO3)2–NaNO3/EG composite FS-PCMs are suggested: the stirring speed of 20 rpm, the evaporation temperature of 98 °C, the melt-impregnation temperature of 280 °C, the cold-pressing pressure of 8 MPa, and the sintering temperature of 300 °C. The results of the present work can provide valuable insights for the large-scale production of the composite FS-PCMs.

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Carbon Cones - a Structure with Unique Properties

MRS Proceedings ◽

10.1557/proc-1057-ii10-46 ◽

2007 ◽

Vol 1057 ◽

Cited By ~ 1

Author(s):

Geir Helgesen ◽

Kenneth D. Knudsen ◽

Jean Patrick Pinheiro ◽

Arne T. Skjeltorp ◽

Eldrid Svåsand ◽

...

Keyword(s):

Carbon Black ◽

Carbon Nanostructures ◽

Large Scale ◽

The Other ◽

Current Status ◽

Scale Production ◽

Plasma Process ◽

Large Scale Production ◽

Nanocarbon Materials ◽

Forms Of Carbon

ABSTRACTLarge-scale production of perfect conical carbon nanostructures that are fundamentally different from the other nanocarbon materials, such as buckyballs and nanotubes, can be made using the so-called Kvaerner Carbon Black & Hydrogen Process. This involves pyrolysis of hydrocarbons using a torch plasma process. The carbon cones that occur appear in five distinctly different forms. In addition, disk-shaped particles may be produced. Here we report about the current status for the experimental research and theoretical modeling of these particles, which have properties different from the other known forms of carbon.

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Characterization of Thin Film CdTe photovoltaic materials deposited by high plasma density magnetron sputtering

MRS Proceedings ◽

10.1557/opl.2011.835 ◽

2011 ◽

Vol 1323 ◽

Cited By ~ 4

Author(s):

A. Abbas ◽

J.W. Bowers ◽

B. Maniscalco ◽

S. Moh ◽

G.D West ◽

...

Keyword(s):

Magnetron Sputtering ◽

Plasma Density ◽

Large Scale ◽

Scale Up ◽

High Plasma ◽

Window Layer ◽

Closed Field ◽

Scale Production ◽

Batch System ◽

High Plasma Density

ABSTRACTA new magnetron sputtering strategy is introduced that utilizes high plasma density (~5mA.cm-2) to avoid or reduce high temperature processing. The technique uses magnetrons of opposing magnetic polarity to create a “closed field” in which the plasma density is enhanced without the need for high applied Voltages. A batch system has been used which employs a rotating vertical drum as the substrate carrier and a symmetrical array of linear magnetrons. The magnetrons are fitted with target materials for each of the thin films required in the photovoltaic (PV) stack including the CdTe absorber layer, CdS window layer, metal contact using the conventional superstrate configuration. The “closed field” sputtering technology allows scale up not only for larger batch system designs but it is also configurable for “in-line” or “roll to roll” formats for large scale production. The morphology of each of the layers is characterized using a variety of structural and optical techniques including Field Emission Gun SEM and X-ray diffraction (XRD).

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Carbon Nanotube Synthesis: A Review

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.1279 ◽

2005 ◽

Vol 3 (1) ◽

Cited By ~ 32

Author(s):

Carole E Baddour ◽

Cedric Briens

Keyword(s):

Carbon Nanotubes ◽

Large Scale ◽

Arc Discharge ◽

Synthesis Method ◽

Fixed Bed ◽

Critical Issue ◽

High Yield ◽

Scale Production ◽

Industrial Companies ◽

Carbon Molecules

Discovered in 1991, carbon nanotubes (CNTs) have reached the forefront of many industrial research projects. Carbon nanotubes are tubular carbon molecules with remarkable mechanical, chemical, thermal and electrical properties, which make them useful in various applications. This paper reviews three methods of synthesizing the nanomaterial, namely arc-discharge, laser-ablation and fixed bed/fluidized bed catalytic. These methods have generated a large interest in many industrial companies to date. At the moment, the most critical issue faced by industrial companies is determining the best synthesis method, which will give the most economical large-scale production of CNTs. Compared to the other two methods, the catalytic technique to synthesize CNTs is simple, inexpensive, energy-efficient and can produce large CNTs quantities of high yield and purity.

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The large-scale production of graphene flakes using magnetically-enhanced arc discharge between carbon electrodes

Carbon ◽

10.1016/j.carbon.2010.07.055 ◽

2010 ◽

Vol 48 (15) ◽

pp. 4570-4574 ◽

Cited By ~ 84

Author(s):

I. Levchenko ◽

O. Volotskova ◽

A. Shashurin ◽

Y. Raitses ◽

K. Ostrikov ◽

...

Keyword(s):

Large Scale ◽

Arc Discharge ◽

Carbon Electrodes ◽

Scale Production ◽

Large Scale Production ◽

Graphene Flakes

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AEM characterization of magnetic nanoparticles encased in graphite shells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137458 ◽

1995 ◽

Vol 53 ◽

pp. 216-217

Author(s):

J. J. Host ◽

M. H. Teng ◽

J. H. Hwang ◽

B. R. Elliott ◽

J. R. Weertman ◽

...

Keyword(s):

Metal Nanoparticles ◽

Large Scale ◽

Arc Discharge ◽

Pure Metal ◽

Scale Production ◽

Crystalline Materials ◽

Large Scale Production ◽

Acid Bath ◽

Significant Research

Since it was discovered that crystalline materials could be encased in graphite shells, protection in this manner has been the focus of significant research. Previously, production of graphite encapsulated crystalline nanoparticles has been reported using an arc discharge between an anode stuffed with a metal oxide and a graphite cathode, resulting in a mixture of carbides, encapsulated carbides and carbonaceous debris. More recently, an arc discharge between metal electrodes has been used to produce large quantities of pure metal nanoparticles, with the addition of graphite to the anode resulting in the large scale production of graphite encapsulated metal nanoparticles (GEMN). In earlier studies, these materials were separated from the other products of the arc discharge only by a magnetic gradient, which does not remove the non-encapsulated crystalline particles. Therefore, the immersion of the product mixture in an acid bath was added as a subsequent processing step. The combined arc discharge/acid bath technique reduces both production and separation problems, producing a large quantity of Fe, Co, and Ni GEMN free from any non-encapsulated metal particles. Subsequent characterization of the resulting material has led to a better understanding of the GEMN produced.

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