Investigation of the plasma composition of a discharge with a self-heating hollow cathode and an active anode in a gas mixture with titanium and hexamethyldisilazane vapors

Abstract The analysis of composition of low-pressure (~0.1-1 mTorr) hollow cathode arc plasma in Ar+N2 gas mixture with Ti+hexamethyldisilazane vapors was carried out by optical emission spectroscopy. The influence of HMDS flow rate (1-10 g/h), discharge current (10-50 A) and Ti-vapors flow on hexamethyldisilazane decomposition degree and plasma composition and was investigated. The proposed plasma activation method provides both an intense flow and a high activation degree of metal vapors, and a sufficient decomposition degree of precursor vapors for the formation of solid TiSiCN coatings at a high deposition rate. Test coatings with a thickness of 6 microns and a hardness of 31 GPa were obtained in 1 hour at 400ºC.

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Externally Heated Hollow Cathode Arc Plasma Source for Experiments in Plasma Wakefield Acceleration

Instruments ◽

10.3390/instruments3030048 ◽

2019 ◽

Vol 3 (3) ◽

pp. 48 ◽

Cited By ~ 1

Author(s):

Ryan Roussel ◽

Gerard Andonian ◽

Claire Hansel ◽

Gerard Lawler ◽

Walter Lynn ◽

...

Keyword(s):

Hollow Cathode ◽

Plasma Source ◽

Plasma Current ◽

Arc Plasma ◽

Time Resolved ◽

Wakefield Acceleration ◽

Beam Parameters ◽

Cathode Arc ◽

Plasma Wakefield ◽

Wakefield Accelerator

An externally heated, hollow cathode arc source was recommissioned at UCLA for use in experiments to drive plasma wakefields with shaped beams at the Argonne Wakefield Accelerator. The hollow cathode arc source provides a robust plasma column with a density in the 10 13 – 10 14 cm − 3 range while external heating of the cathode allows the plasma arc regime to be accessed with applied voltages down to 20 V. Overall source operating principals are described, along with time-resolved plasma current measurements and plasma density characterization with the use of a triple Langumir probe. The results show that relevant plasma densities that match facility beam parameters are readily achievable.

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Diamond growth by hollow cathode arc plasma chemical vapor deposition

Journal of Materials Research ◽

10.1557/jmr.1998.0424 ◽

1998 ◽

Vol 13 (11) ◽

pp. 3114-3121 ◽

Cited By ~ 11

Author(s):

Gou-Tsau Liang ◽

Franklin Chau-Nan Hong

Keyword(s):

Chemical Vapor Deposition ◽

Substrate Temperature ◽

Hollow Cathode ◽

Vapor Deposition ◽

Diamond Films ◽

Chemical Vapor ◽

Arc Plasma ◽

Plasma Chemical ◽

Plasma Chemical Vapor Deposition ◽

Cathode Arc

Hollow cathode arc plasma chemical vapor deposition was employed to grow crystalline diamond films using 1.5% to 7% of methane in hydrogen. The growth rate was as high as 3.2 μ/h when using 5% CH4/H2 at a pressure of 15 Torr and a substrate temperature of 1083 K. However, an intermediate layer of several hundred nanometers was observed at the film-substrate interface by cross-section SEM. Raman and XPS characterizations showed that the interfacial layer consisted of sp2 carbon and TaC with Ta vaporized from the hot cathode tube. XRD and XPS results further showed that the deposited diamond films also contained TaC. Ta composition in the film increased with the increase of growth pressure, the reduction of substrate temperature, and the increase of H2 flow in the Ta tube. The diamond films deposited by using CHCl3 as carbon source had Ta concentrations one order of magnitude higher than those using CH4, as shown by XPS results, but the nucleation densities using CHCl3 were always higher than those using CH4.

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