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Study of plasma–solid interaction in electronegative gas mixtures at higher pressures

Rudolf Hrach, Štěpán Roučka, Věra Hrachová, Lukáš Schmiedt
2009 Vacuum  
Models We prepared a computer experiment devoted to the study of the role of negative ions in the formation of sheath surrounding substrates immersed into plasma and the influence of plasma pressure on  ...  Negative ions in such plasmas affect the transport of charged species from the plasma to immersed substrates and in this way influence the physical and chemical processes both in the sheath and on the  ... 
doi:10.1016/j.vacuum.2009.06.008 fatcat:eppffzxj5vcunjikrdeobrc7sq

Addressing the effects of background plasma and wake formation on nanosatellites with electric propulsion using a 3D Particle In Cell code

A.J.R. Lopez-Arreguin, E. Stoll
2019 Results in Physics  
During one orbital period the passive CubeSat drives an isotropic impingement of plasma electrons, that (because their higher mobility regarding ions) govern a negative surface potential.  ...  The experiment was repeated in different orbit altitudes with varying plasma densities, showing that in space zones with greater concentration of plasma ions, the satellite potential is less negative,  ...  We also thank Instituto Potosino de Investigacion Cientifica y Tecnologica (IPICYT) through Thubat Kaal 2.0 HPC for their support of computing time. We are thankful to Prof.  ... 
doi:10.1016/j.rinp.2019.102442 fatcat:vvu6rxqwzbb6rjfbk6x2nrt5hi

Negative ion production near a divertor plate

F. Taccogna, R. Schneider, K. Matyash, S. Longo, M. Capitelli, D. Tskhakaya
2007 Journal of Nuclear Materials  
The importance of negative ions for the sheath potential and hydrogen fluxes on to the divertor will be calculated for different parameters.  ...  To study this effect, we have developed a 1D-3V Particle-in-Cell electrostatic model of the electro-negative sheath.  ...  the formation of negative ions by an electron capture from the wall [14] are included as directly related to the negative ion production.  ... 
doi:10.1016/j.jnucmat.2007.01.039 fatcat:ljczrw7zvbdqnh2es5bsezbjou

Computational study of sheath structure in chemically active plasmas

P. Cerny, S. Novak, R. Hrach, V. Hrachova
2011 European Physical Journal : Applied physics  
A pressure dependence of the sheath region in electronegative plasma is shown, too.  ...  The interaction is studied not only in case when a constant value of voltage bias on the immersed substrate is kept, but also when sinusoidal voltage bias is applied.  ...  The second part of the contribution deals with a study of the sheath structure during the interaction of a multicomponent plasma consisting of electrons and five species of both positive and negative ions  ... 
doi:10.1051/epjap/2011110164 fatcat:yazef2lpxfdbvaizliqvogwstu

Interaction of Biased Electrodes and Plasmas: Sheaths, Double Layers and Fireballs [article]

Scott D. Baalrud, Brett Scheiner, Benjamin Yee, Matthew M. Hopkins, Edward Barnat
2019 arXiv   pre-print
These represent complex self-organized responses of the plasma that depend not only on the local influence of the electrode, but also on the global properties of the plasma and the other boundaries that  ...  The plasma-electrode interaction is mediated by an intervening sheath structure that influences properties of the electrons and ions contacting the electrode surface, as well as how the electrode influences  ...  This work was supported by the Office of Fusion Energy Science at the U.S. Department of Energy under contracts DE-AC04-94SL85000 and DE-SC0016473.  ... 
arXiv:1911.06424v1 fatcat:yud4nuphnneh3ogw7yqcequhqm

Two dimensional computer simulation of plasma immersion ion implantation

K. G. Kostov, J. J. Barroso, M. Ueda
2004 Brazilian journal of physics  
A particle-in-cell computer simulation is used to study the time-dependent evolution of the plasma sheath surrounding two-dimensional objects during process of plasma immersion ion implantation.  ...  The problems arise from the non-uniform plasma density and expansion of plasma sheath.  ...  One of the authors, K.G. Kostov, wishes to thank FAPESP for a visiting researcher scholarship, grant 02/08486-5.  ... 
doi:10.1590/s0103-97332004000800033 fatcat:fbuldkfslng7fgegibrmo56eji

3D-PIC Modelling of a low temperature plasma sheath with wall emission of negative particles and its application to NBI sources

ivar mauricio montellano, Dirk Wünderlich, Serhiy Mochalskyy, Ursel Fantz
2019 Journal of Physics D: Applied Physics  
Results of basic investigations on the influence of the magnetic fields and the meniscus shape on the extraction of negative ions, co-extraction of electrons and the beamlet quality are presented.  ...  The 3D particle-in-cell (PIC) code ONIX (orsay negative ion extraction) is a versatile tool for simulating the formation and extraction of negative hydrogen ions and co-extracted electrons in caesiated  ...  Acknowledgments The author would like to thank Dr Loïc Schiesko for providing results of the application of the model by Schwager [39] for electronegative plasmas.  ... 
doi:10.1088/1361-6463/ab0f44 fatcat:x7kfsjhskzdennauic4chuitum

A particle-in-cell plus Monte Carlo study of plasma-induced damage of normal incidence collector optics used in extreme ultraviolet lithography

R. C. Wieggers, W. J. Goedheer, M. R. Akdim, F. Bijkerk, P. A. Zegeling
2008 Journal of Applied Physics  
The relation between the time and position at which the ions are created and their final energy is studied, revealing how the evolution and the properties of the sheath influence the amount of sputtered  ...  The time evolution of the low density argon plasma is simulated during and after the EUV pulse and the ion-induced sputtering of the coating material of a normal incidence collector mirror is computed.  ...  The influence of the source intensity and the pressure on the acceleration of ions in the sheath region and the resulting sputtering of the 7 .  ... 
doi:10.1063/1.2829783 fatcat:o5jm4wjoxzhd7kbfdjj3qibt2e

Oxygen ion energy distribution: Role of ionization, resonant, and nonresonant charge-exchange collisions

N. Yu. Babaeva, J. K. Lee, J. W. Shon, E. A. Hudson
2005 Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films  
The roles of ionization, resonant and nonresonant charge-exchange collisions in the formation of ion energy distribution ͑IED͒ at the electrodes is investigated.  ...  By turning off/on the corresponding collisional processes, it is shown that ionization can play an essential role in formation of the IED structure.  ...  This work was supported in part by the Lam Research Corporation, Samsung Electronics, and Teralevel Nano Devices Project, 21c Frontier R&D Program of Korea Ministry of Science and Technology.  ... 
doi:10.1116/1.1943451 fatcat:wmnl76duqra7dlnwpvttwcrske

Parasitic current collection by solar arrays in LEO

V.A. Davis, B.M. Gardner
1995 International Conference on Plasma Science (papers in summary form only received)  
In addition, this current influences the current balance that determines the floating potential of the spacecraft.  ...  One of the objectives of the Air Force (PL/GPS) PASP Plus experiment is an improved understanding of parasitic current collection.  ...  Ions are attracted to exposed conductors on the spacecraft surface, as the spacecraft body is negative with respect to the plasma.  ... 
doi:10.1109/plasma.1995.531680 fatcat:2vvvvwaqtramfidkjweqiqecpm

Influence of Magnetic Fields and Biasing on the Plasma of a RF Driven Negative Ion Source

D. Wünderlich, R. Gutser, U. Fantz
2007 AIP Conference Proceedings  
Their current status is presented: a particle-in-cell-code (PIC) is used to study the influence of filter fields and bias voltage on the plasma flow onto the plasma grid.  ...  In the second code the survival probability of negative ions produced on the surface of the plasma grid is estimated using test-particles.  ...  CONCLUSIONS The influence of a magnetic filter field and biasing on the plasma and on single negative ions was studied using a PIC code and a test particle code respectively.  ... 
doi:10.1063/1.2773645 fatcat:qinmn3fmkvgg7ns6hzrykv4aly

Modeling of ions energy distribution profile of electronegative plasma discharges with an efficient Monte Carlo simulator [article]

M. Ardehali
1998 arXiv   pre-print
The crucial role that Ions Energy Distribution Function (IEDF) at the electrodes plays in plasma processing of semiconductor materials demands that this quantity be predicted with high accuracy and with  ...  In this work, an efficient Particle-in-cell/Monte-Carlo (PIC/MC) simulator is developed to model IEDF at the electrodes of electronegative plasma discharges.  ...  Urbassek, "Influence of plasma extraction on a cylin- drical low-pressure RF discharge: A PIC-MC study," IEEE Trans. Plasma Sci., vol. 23, pp. 103-109, 1995. [16] M. Goto, Y, Kondoh, and A.  ... 
arXiv:physics/9810026v2 fatcat:oztvhn6k4rgihf3jphjaawxcfi

Plasma-wall transition and sheath formation [article]

Giovanni Manfredi, Fabrice Valsaque
2021 arXiv   pre-print
Applications to the theory of electrostatic probes are illustrated by means of a recently developed kinetic model. The influence of the probe on ion temperature measurements is studied in detail.  ...  A review of the theoretical and computational aspects of plasma-wall transition is presented. The conditions for the existence of plasma sheaths in front of a solid surface are established.  ...  Gunn for his expertise on RFA probes and for the fruitful collaboration that led to the results reported in Sec. III.  ... 
arXiv:2108.01889v2 fatcat:lmrgsay6z5dwfjkjlkqqnobzfq

Plasma Density Analysis of CubeSat Wakes in the Earth's Ionosphere

Robert M. Albarran, Aroh Barjatya
2016 Journal of Spacecraft and Rockets  
V ϕ s = sheath potential, V χ = ion focusing parameter, m ω p = plasma frequency, rad · s −1  ...  Spinning or tumbling CubeSats with Langmuir probes deployed on booms will render spin-modulated plasma densities as the probes move in and out of the spacecraft wake.  ...  The formation of an ion focus region downstream of a negatively charged conductor with dimensions comparable to the Debye sheath thickness is thus of significant concern when developing CubeSat Langmuir  ... 
doi:10.2514/1.a33402 fatcat:wtb6oy7w2zhi7go6dfed3pz4ne

Time evolution of an ion-ion plasma after the application of a direct current bias voltage

Vikas Midha, Badri Ramamurthi, Demetre J. Economou
2002 Journal of Applied Physics  
A one-dimensional fluid model was developed to investigate the time evolution of a positive ion-negative ion ͑ion-ion͒ plasma after the application of a direct current ͑dc͒ bias voltage.  ...  The applied bias is shielded and space charge sheaths are formed within the time scale of ion response ͑ion plasma frequency͒.  ...  ACKNOWLEDGMENTS The authors are grateful to the National Science Foundation ͑CTS-9713262 and CTS-0072854͒ and the State of Texas ͑Texas Advanced Technology Program͒ for financial support of this work.  ... 
doi:10.1063/1.1468256 fatcat:7c7josllj5gz5nrgyuedf5urae
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