Intensities of Hβ and Hγ in Hydrogen Plasma Spectrum with High RF Power Levels at ICP

2013 ◽  
Vol 774-776 ◽  
pp. 471-478
Author(s):  
Song Bai Wang ◽  
Guang Jiu Lei ◽  
Ming Li ◽  
Li Ming Yu ◽  
Ying Nan Bu ◽  
...  
Keyword(s):  
Stark Effect ◽  
Hydrogen Plasma ◽  
Input Power ◽  
Ion Source ◽  
Spectral Lines ◽  
Rf Plasma ◽  
Rf Power ◽  
Balmer Series ◽  
Rf Ion Source ◽  
Plasma Spectrum

In high-power RF ion source, three different regions of the Hβand Hγintensities in the Balmer series of spectral lines for atomic hydrogen plasma were investigated. Three different regions of the Hβand Hγintensities were detected by the increase of input power (0-6 kW) at ICP. In hydrogen plasma spectrum, the Hβand Hγintensities showed three processes: slowly increase, quickly increase and stable saturation. The Stark effect in strong electrical field plays a crucial role in dominating the Balmer Hβand Hγemissions from high-density RF plasma.

Temperature Determination in an Inductively Coupled rf Plasma

1976 ◽  
Vol 30 (1) ◽  
pp. 34-38 ◽  
Author(s):  
K. Visser ◽  
F. M. Hamm ◽  
P. B. Zeeman
Keyword(s):  
Atmospheric Pressure ◽  
Thermal Equilibrium ◽  
Hydrogen Plasma ◽  
Spectral Lines ◽  
Rf Plasma ◽  
Temperature Profiles ◽  
Inductively Coupled ◽  
Temperature Method ◽  
The Difference ◽  
Line Temperature

Simultaneous relative radiances of the Hβ, Hγ, and Hδ spectral lines of hydrogen were measured sequentially at various lateral positions in an inductively coupled rf argon-hydrogen plasma operated at atmospheric pressure (12 kW, 9 MHz). Measurements to take self-absorption into account were also performed. By applying an Abel integral inversion, a radial radiance profile for each line was obtained. With the two-line temperature method, simultaneous temperature profiles were obtained from each of the three line-pairs. The difference between these three sets of values and the negative values obtained for the Hγ, Hδ pair indicates that thermal equilibrium does not exist in this plasma.

Multi-antenna RF Ion Source at a High RF Power Level

2009 ◽  
Author(s):  
Y. Oka ◽  
T. Shoji ◽  
O. Kaneko ◽  
Y. Takeiri ◽  
K. Tsumori ◽  
...  
Keyword(s):  
Power Level ◽  
Ion Source ◽  
Rf Power ◽  
Rf Ion Source

scholarly journals Investigation and diagnostics of plasma flows in a pulsed plasma accelerator for experimental modelling of processes in tokamaks

2021 ◽  
Vol 5 (4) ◽  
pp. 198-210
Author(s):  
M. K. Dosbolayev ◽  
A. B. Tazhen ◽  
T. S. Ramazanov
Keyword(s):  
Vacuum Chamber ◽  
Arc Discharge ◽  
Hydrogen Plasma ◽  
Beam Current ◽  
Plasma Accelerator ◽  
Spectral Lines ◽  
Pulsed Plasma ◽  
Stark Broadening ◽  
Balmer Series ◽  
Faraday Cup

This paper presents the experimental results on electron, ion temperatures and densities in a pulsed plasma accelerator. The values of electron densities and temperatures were computed using the methods of relative intensities of Hα and Hβ lines, Hβ Stark broadening, and the technique is based on Faraday cup beam current measurements. In this work, a linear optical spectrometer S-100 was used to acquire the emission spectra of hydrogen and air plasmas. In this spectrum, there are some lines due to Fe, Cu, N2, O2, and H2. The series of visible lines in the hydrogen atom spectrum are named the Balmer series. The spectral emissions of iron and copper occur throughout the gas breakdown and ignition of an arc discharge, during the erosion and sputtering of materials. The vacuum chamber and coaxial electrodes were made. The electron temperatures and densities in a pulsed plasma accelerator, measured via relative intensities of spectral lines and Stark broadening, at a charging voltage of a capacitor bank of 3 kV and a working gas pressure in a vacuum chamber of 40 mTorr, were 2.6 eV and 1.66 · 1016 cm−3 for hydrogen plasma. These results were compared with the Faraday cup beam current measurements. However, no match was found. Considering and analyzing this distinction, we concluded that the spectral method of plasma diagnostics provides more accurate results than electrical measurement. The theory of probe measurements can give approximate results in a moving plasma.

scholarly journals From the Vector to Scalar Perturbations Addition in the Stark Broadening Theory of Spectral Lines

Universe ◽  
2021 ◽  
Vol 7 (6) ◽  
pp. 176
Author(s):  
Valery Astapenko ◽  
Andrei Letunov ◽  
Valery Lisitsa
Keyword(s):  
Spectral Line ◽  
Stark Effect ◽  
Coulomb Field ◽  
Spectral Lines ◽  
Alternative Methods ◽  
Scalar Perturbation ◽  
Numerical Comparison ◽  
Line Shapes ◽  
Stark Effects ◽  
The Impact

The effect of plasma Coulomb microfied dynamics on spectral line shapes is under consideration. The analytical solution of the problem is unachievable with famous Chandrasekhar–Von-Neumann results up to the present time. The alternative methods are connected with modeling of a real ion Coulomb field dynamics by approximate models. One of the most accurate theories of ions dynamics effect on line shapes in plasmas is the Frequency Fluctuation Model (FFM) tested by the comparison with plasma microfield numerical simulations. The goal of the present paper is to make a detailed comparison of the FFM results with analytical ones for the linear and quadratic Stark effects in different limiting cases. The main problem is connected with perturbation additions laws known to be vector for small particle velocities (static line shapes) and scalar for large velocities (the impact limit). The general solutions for line shapes known in the frame of scalar perturbation additions are used to test the FFM procedure. The difference between “scalar” and “vector” models is demonstrated both for linear and quadratic Stark effects. It is shown that correct transition from static to impact limits for linear Stark-effect needs in account of the dependence of electric field jumping frequency in FFM on the field strengths. However, the constant jumping frequency is quite satisfactory for description of the quadratic Stark-effect. The detailed numerical comparison for spectral line shapes in the frame of both scalar and vector perturbation additions with and without jumping frequency field dependence for the linear and quadratic Stark effects is presented.

scholarly journals Magnetic nozzle radiofrequency plasma thruster approaching twenty percent thruster efficiency

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kazunori Takahashi
Keyword(s):  
Magnetic Field ◽  
Electric Propulsion ◽  
Transfer Efficiency ◽  
Rf Plasma ◽  
Power Transfer ◽  
Rf Power ◽  
Plasma Production ◽  
Magnetic Nozzle ◽  
Plasma Thruster ◽  
Power Transfer Efficiency

AbstractDevelopment of a magnetic nozzle radiofrequency (rf) plasma thruster has been one of challenging topics in space electric propulsion technologies. The thruster typically consists of an rf plasma source and a magnetic nozzle, where the plasma produced inside the source is transported along the magnetic field and expands in the magnetic nozzle. An imparted thrust is significantly affected by the rf power coupling for the plasma production, the plasma transport, the plasma loss to the wall, and the plasma acceleration process in the magnetic nozzle. The rf power transfer efficiency and the imparted thrust are assessed for two types of rf antennas exciting azimuthal mode number of $$m=+1$$ m = + 1 and $$m=0$$ m = 0 , where propellant argon gas is introduced from the upstream of the thruster source tube. The rf power transfer efficiency and the density measured at the radial center for the $$m=+1$$ m = + 1 mode antenna are higher than those for the $$m=0$$ m = 0 mode antenna, while a larger thrust is obtained for the $$m=0$$ m = 0 mode antenna. Two-dimensional plume characterization suggests that the lowered performance for the $$m=+1$$ m = + 1 mode case is due to the plasma production at the radial center, where contribution on a thrust exerted to the magnetic nozzle is weak due to the absence of the radial magnetic field. Subsequently, the configuration is modified so as to introduce the propellant gas near the thruster exit for the $$m=0$$ m = 0 mode configuration and the thruster efficiency approaching twenty percent is successfully obtained, being highest to date in the kW-class magnetic nozzle rf plasma thrusters.

Negative-Ion Implantation

1994 ◽  
Vol 354 ◽  
Author(s):  
Junzo Ishikawa
Keyword(s):  
Ion Implantation ◽  
Negative Ions ◽  
Ion Source ◽  
Negative Ion ◽  
Rf Plasma ◽  
Ion Currents ◽  
Promising Technique ◽  
Surface Charging ◽  
Silicon Carbon ◽  
A Charge

AbstractNegative-ion implantation is a promising technique for forthcoming ULSI (more than 256 M bits) fabrication and TFT (for color LCD) fabrication, since the surface charging voltage of insulated electrodes or insulators implanted by negative ions is found to saturate within so few as several volts, no breakdown of insulators would be expected without a charge neutralizer in these fabrication processes. Scatter-less negative-ion implantation into powders is also possible. For this purpose an rf-plasma-sputter type heavy negative-ion source was developed, which can deliver several milliamperes of various kinds of negative ion currents such as boron, phosphor, silicon, carbon, copper, oxygen, etc. A medium current negative-ion implanter with a small version of this type of ion source has been developed.

scholarly journals Fringe structures and tunable bandgap width of 2D boron nitride nanosheets

2014 ◽  
Vol 5 ◽  
pp. 1186-1192 ◽  
Author(s):  
Peter Feng ◽  
Muhammad Sajjad ◽  
Eric Yiming Li ◽  
Hongxin Zhang ◽  
Jin Chu ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Hydrogen Plasma ◽  
Hydrogen Gas ◽  
Spectral Lines ◽  
Bandgap Width ◽  
Raman Scattering Spectroscopy ◽  
Boron Nitride Nanosheets ◽  
Tunable Bandgap ◽  
Curved Structures ◽  
Digitally Controlled

We report studies of the surface fringe structures and tunable bandgap width of atomic-thin boron nitride nanosheets (BNNSs). BNNSs are synthesized by using digitally controlled pulse deposition techniques. The nanoscale morphologies of BNNSs are characterized by using scanning electron microscope (SEM), and transmission electron microscopy (TEM). In general, the BNNSs appear microscopically flat in the case of low temperature synthesis, whereas at high temperature conditions, it yields various curved structures. Experimental data reveal the evolutions of fringe structures. Functionalization of the BNNSs is completed with hydrogen plasma beam source in order to efficiently control bandgap width. The characterizations are based on Raman scattering spectroscopy, X-ray diffraction (XRD), and FTIR transmittance spectra. Red shifts of spectral lines are clearly visible after the functionalization, indicating the bandgap width of the BNNSs has been changed. However, simple treatments with hydrogen gas do not affect the bandgap width of the BNNSs.

scholarly journals The Effect of Plasma Pretreatment on the Morphology and Properties of Hitus Coatings

2020 ◽  
Vol 20 (1) ◽  
pp. 21-29
Author(s):  
Lenka Kvetková ◽  
Petra Hviščová ◽  
Dávid Medveď ◽  
František Lofaj
Keyword(s):  
Mechanical Properties ◽  
New Technology ◽  
Rf Plasma ◽  
Plasma Power ◽  
Rf Power ◽  
Properties Of Coatings ◽  
Plasma Pretreatment ◽  
Significant Change ◽  
Scratch Behavior

Abstract WC coatings prepared by High Target Utilization Sputtering (HITUS), a relatively new technology, were deposited on three types of substrates. These were silicon (111), steel (100Cr6), and ceramic (WC-Co). The influence of RF plasma power pretreatment on final properties of WC coatings was investigated with two interlayer materials for bonding. The morphology, roughness, and mechanical properties of coatings were studied. The relation between plasma RF power and roughness was found. No significant change in mechanical properties was detected with change in plasma RF power. The dependence of nanohardness and scratch behavior on HITUS WC coatings was investigated.

In Situ Auger Spectroscopy Investigation of InP Surfaces Treated in RF Hydrogen and Hydrogen/Methane/Argon Plasmas

1995 ◽  
Vol 386 ◽  
Author(s):  
J. E. Parmeter ◽  
R. J. Shul ◽  
P. A. Miller
Keyword(s):  
Hydrogen Plasma ◽  
Auger Spectroscopy ◽  
Surface Roughening ◽  
Rf Power ◽  
Plasma Exposure ◽  
Argon Plasmas ◽  
Etch Rates ◽  
Phosphorus Depletion ◽  
Oxygen Impurities

ABSTRACTWe have used in situ Auger spectroscopic analysis to investigate the composition of InP surfaces cleaned in rf H2 plasmas and etched in rf H2/CH4/Ar plasmas. In general agreement with previous results, hydrogen plasma treatment is found to remove surface carbon and oxygen impurities but also leads to substantial surface phosphorus depletion if not carefully controlled. Low plasma exposure times and rf power settings minimize both phosphorus depletion and surface roughening. Surfaces etched in H2/CH4/Ar plasmas can show severe phosphorus depletion in high density plasmas leading to etch rates of ∼ 700 Å/min, but this effect is greatly reduced in lower density plasmas that produce etch rates of 30–400 Å/min.

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