Charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam
The dependences of potential of macroparticle from the parameters and characteristics of plasma-beam system are
 studied. The modeling of charging processes of the macroparticles in approach of ions and electrons orbit motion
 limited theory made. The effect of electron emission from...
Saved in:
| Published in: | Вопросы атомной науки и техники |
|---|---|
| Date: | 2011 |
| Main Authors: | , , |
| Format: | Article |
| Language: | English |
| Published: |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2011
|
| Subjects: | |
| Online Access: | https://nasplib.isofts.kiev.ua/handle/123456789/90891 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Journal Title: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| Cite this: | Charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam / A.A. Bizyukov, K.N. Sereda, A.D. Chibisov // Вопросы атомной науки и техники. — 2011. — № 1. — С. 107-109. — Бібліогр.: 6 назв. — англ. |
Institution
Digital Library of Periodicals of National Academy of Sciences of Ukraine| _version_ | 1860246518832824320 |
|---|---|
| author | Bizyukov, A.A. Sereda, K.N. Chibisov, A.D. |
| author_facet | Bizyukov, A.A. Sereda, K.N. Chibisov, A.D. |
| citation_txt | Charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam / A.A. Bizyukov, K.N. Sereda, A.D. Chibisov // Вопросы атомной науки и техники. — 2011. — № 1. — С. 107-109. — Бібліогр.: 6 назв. — англ. |
| collection | DSpace DC |
| container_title | Вопросы атомной науки и техники |
| description | The dependences of potential of macroparticle from the parameters and characteristics of plasma-beam system are
studied. The modeling of charging processes of the macroparticles in approach of ions and electrons orbit motion
limited theory made. The effect of electron emission from macroparticle has been investigated taking into account the
space charge on potential of macroparticle.
Вивчено залежність потенціалу макрочастинки в пучково-плазмовій системі від її параметрів та
характеристик макрочастинки. Моделювання процесу зарядки проводилося в наближенні орбітальної моделі
руху іонів й електронів плазми, а також електронів пучка. Досліджено вплив електронної емісії з мікрочасток,
розігрітих до високих температур, на величину потенціалу з урахуванням обмеження емісійного електронного
струму власним об'ємним зарядом.
Изучена зависимость потенциала макрочастицы в пучково-плазменной системе от ее параметров и
характеристик макрочастицы. Моделирование процесса зарядки проводилось в приближении орбитальной
модели движения ионов и электронов плазмы, а также электронов пучка. Исследовано влияние электронной
эмиссии с макрочастиц, разогретых до высоких температур, на величину потенциала c учетом ограничения
эмиссионного электронного тока собственным объемным зарядом.
|
| first_indexed | 2025-12-07T18:37:10Z |
| format | Article |
| fulltext |
CHARGING PROCESSES OF METAL MACROPARTICLES
IN THE LOW-TEMPERATURE PLASMA AT PRESENCE
OF HIGH-ENERGY ELECTRON BEAM
A.A. Bizyukov1, K.N. Sereda1, A.D. Chibisov2
1V.N. Karazin Kharkov National University, Kharkov, Ukraine;
2V.V. Dokuchaev Kharkov National Agrarian University, Kharkov, Ukraine
E-mail: sekons@mail.ru, chibisov.alexandr@mail.ru
The dependences of potential of macroparticle from the parameters and characteristics of plasma-beam system are
studied. The modeling of charging processes of the macroparticles in approach of ions and electrons orbit motion
limited theory made. The effect of electron emission from macroparticle has been investigated taking into account the
space charge on potential of macroparticle.
PACS: 52.40.Hf
1. INTRODUCTION
“Dusty plasma” is one of most intensively developing
branches in plasma physics. In particular, it is widely used in
technology of hardening of tools and in mechanical
engineering the coating got by condensation of substance
from a plasma stream, generated by low pressure arc, in a
conditions of ionic bombardment of a condensate. The
presence on a cathode surface of quickly moving cathodes
spots is the typical feature of the arc discharge in vacuum.
Erosion of cathode surface by vacuum arc caused by a
cathode spot generates particle, which neutral atoms, ions
and macroparticles, for example the drops and hard
fragments of a cathode material. The contribution of a drop
phase into the total mass flux of a cathode material may be as
high as 90 %. Typical size of the macroparticles is in the
range of 1…100 microns; however larger and smaller
particles may be observed. The velocity of drop flux is in the
range of 102…104 cm/s [1]. The concentration of the
macroparticles depends on a material of the cathode, as well
as the arc discharge current and thermal mode and geometry
of the cathode [2]. The presence of the macroparticle phase
in plasma of the vacuum arc discharge limits applicability of
this method in many areas including optics, micro-
electronics, the precise mechanics, medicine. Presence of
macroparticles in the coating has a harmful impact on its
most important characteristics such as adhesion to the
surface, porosity, surface roughness; they become
unsatisfactory for the application in wide spectrum of
technological problems. Most popular solution, which helps
to reduce drops concentration in plasma flow of the vacuum
arc, is based on magnetic separation of trajectories of drops
and ions. A considerable quantity of various filters and the
separators effectively deleting a drop phase from a plasma
flow have been developed [3]. However, the removal of the
drops decreases the deposition rate and with separation
applied the efficiency of this method is comparable with
others such as magnetron and ion beam sputtering methods.
2. STEADY-STATE POTENTIAL
OF THE MACROPARTICLE IN PLASMA-
BEAM SYSTEM
The macroparticles in plasma are charged to some
potential ϕs, which is determined by plasma parameters as
well as the size and properties of macroparticles. It can be
calculated similarly to Ref. [4] by using the orbital model.
Injection of the high-energy electron beam in the
macroparticle-plasma system increases the electron current
on the macroparticle surface and leads to substantial growth
of its potential as well as temperature of the macroparticles.
The increase of the macroparticle temperature can lead to
thermionic emission from its surface. In addition, there is an
essential contribution of the secondary electron emission
induced by high-energy beam electrons.
The equation describing the balance of charge currents
on a macroparticle surface should take into account the
secondary electron and thermionic emissions in plasma-
beam system :
( )( ) 01 =+−−++ emsbebei IeIII ϕεδ , (1)
where eδ is the coefficient of the secondary electron
emission for the macroparticle material,
( )bsebbb evnaI εϕπ −= 12 is the electron beam current
on a surface of a macroparticle, is the density of the
electron beam,
bn
ebeb mkv ε= is the electron beam
velocity, is the elementary electronic charge, e bε is the
electron beam energy, is the radius of macroparticle. a
The expressions for ion and electron currents is
similar to that, which may be found in the theory of
probes:
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
−=
i
s
Tii T
evnaI ϕπ 18 0
2 ,
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
=
e
s
Tee T
evnaI ϕπ exp8 0
2 ,
where is the plasma density, and are the electron
and ion temperatures respectively, and are the
thermal velocities of electrons and ions. The contribution of
the secondary electron emission caused by plasma electrons in
cold plasma is negligible, because the energy of plasma
electrons bombarding the surface of macroparticle, is close to
zero. Therefore, the secondary electron emission from the
macroparticle surface is the only term, which is considered in
the equation of balance of charge currents.
0n eT iT
Tev Tiv
The electron beam current on a surface of
macroparticle is determined by the following expression:
PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. 2011. № 1. 107
Series: Plasma Physics (17), p. 107-109.
mailto:sekons@mail.ru
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
−=
b
s
ebbb
evnaI
ε
ϕ
π 12 ,
The secondary electron current can be calculated using
the formula:
( )sbebes eII ϕεδ −= ,
In the present work we assume that the particles are
heated to high temperature so that the effect of thermionic
emission has an essential influence on the potential of a
macroparticle. The maximum emission from the surface
of the macroparticle due to the thermionic emission can
be calculated using the formula taking into account the
effect of Shottki [5]: thj
( ) [ T)(
143
14322
)Tsin(
TT2 EW
th e
F
Faj −−
−
−
=
π
108
] .
Here the current density is in units
214793 1037,2 cmAeme ⋅=−h , electric field E is in units
cmVem 9452 1015,5 ⋅=−h , the macroparticle temperature
and work function W in units . T eVme 1,2724 =−h
At high temperatures of macroparticles character
the high emission ability of metals that can lead to
restriction of an emission current by own bulk charge. In
this case the current density of thermionic electrons is
described by the law «3/2» which in spherical coordinate
system can be expressed as:
2
2/3
2/3 9
24
α
ϕs
m
ej ⋅= ,
where is the 2α tabulated function [6].
1000 1500 2000 2500 3000 3500
-5000
-4000
-3000
-2000
-1000
0
ΙΙΙΙΙΙ
2
1
Τ, Κ
ϕ s ,
V
Fig. 1. The dependence of tungsten macroparticle sϕ
with the size on temperature. Plasma
density is , electron beam density is
and electron beam energy is
cma 410−=
39
0 10 −= cmn
3910 −= cmnb
bε =10 keV (1); bε =5 keV (2),
Taking into account the possible limitation of the
current of electrons emitted from the macroparticle by
spatial charge in the formula (1), it is determined by
expression:
emI
⎪⎩
⎪
⎨
⎧
>
<
=
.
,
2/3,2/3
2/3
jjI
jjI
I
th
thth
em
Fig. 1 shows the numerical solution for the equation
(1) for two energies of an electron beam. Temperature
range I in Fig. 1 corresponds to insignificant thermionic
emission. Thus, the macroparticle potential is defined by
interaction with beam electrons and plasma ions. The
range II corresponds to increasing contribution of the
thermionic current in increase of macroparticle charge
that leads to decrease of its potential. Range III
corresponds to formation of a layer of electron spatial
charge around the macroparticle and, consequently, limit
of a current of thermionic emission to value defined by
the Child-Langmuir law.
Fig. 2 shows the dependence of potential of a
macroparticle on energy of the electronic beam, obtained
by the numerical solution of equation (1) for three
temperatures of a macroparticle. The common trend of all
three solutions is growth of macroparticle potential with
increase of the electron beam energy. However, growth
rate macroparticle temperature decreases with increase of
the temperature. This effect is related to increase of the
thermal emission of a macroparticle. At small
temperatures (curve 1) and high macroparticle potential,
there is no limitation of the emission current by the
electron spatial charge in all range of the beam energy.
2000 3000 4000 5000 6000 7000 8000
-4000
-3500
-3000
-2500
-2000
-1500
-1000
-500
0
500
3
2
1
εb, eV
ϕ s ,
V
Fig. 2. The dependence of tungsten macroparticle sϕ
with the size on ion beam energy. Plasma
density is , electron beam density is
. The macroparticle temperature is:
cma 410−=
39
0 10 −= cmn
3910 −= cmnb
KT 1000= (1); KT 2250= (2); (3). KT 3000=
When macroparticle temperature increases (curves 2
and 3) the dependences of potential from electron beam
energy becomes similar in energy range 2000…4200 eV
and at various temperatures. At these parameters electron
emission from a macroparticle does not depend on its
temperature and it is defined by the Child-Langmuir law.
REFERENCES When the macroparticle potential is increased, the thermal
emission is not limitation by the spatial charge any more
(a curve 2 at eVb 4200>ε ). Thus, the dependence of
potential on the beam energy becomes similar to curve 1.
For the highest temperatures of macroparticles (curve 3)
the thermal emission current is limited by the spatial
charge in all range of the investigated beam energy.
1. G.V. Samsonov. Nitridy. Kiev: “Naukova dumka”,
1969, p. 69 (in Russian).
2. V.I. Rakhovskii. Physicheskie osnovy kommutacii
electricheskogo toka v vacuume. М.: ”Nauka”, 1970,
p. 82 (in Russian).
3. I.I. Aksenov. Magnetically filtered vacuum-arc plasma
deposition systems // Problems of Atomic Science and
Technology. Series ”Plasma Physics” (8). 2002, N 5,
p. 139-141.
3. CONCLUSIONS
The macroparticle potential in plasma-beam system is
studied in dependence of its characteristics. When the
macroparticle temperature increases, the thermal emission
of the ions has the significant effect on potential of a
macroparticle. Steady-state potential of a macroparticle is
strongly influenced by thermal emission, which is limited
by spatial charge according to Child-Langmuir law.
4. A.А. Bizyukov, E.V. Romaschenko, K.N. Sereda,
А.D. Chibisov. Electricheskii potential macrochstitsy v
puchkovo-plasmennyh systemah // Plasma Physics
Reports. 2009, v. 35, N 6, p. 547-550 (in Russian).
5. E.L. Murphy, R.H. Good. Thermionic Emission, Field
Emission, and the Transition Region // Physical Review.
1956, v. 102, N 6, p. 1464–1473.
6. V.L. Granovsky. Electric current in gases.
М.: “Nauka”, 1971, p. 39-40.
Article received 01.10.10
ПРОЦЕССЫ ЗАРЯДКИ МЕТАЛЛИЧЕСКИХ МАКРОЧАСТИЦ НИЗКОТЕМПЕРАТУРНОЙ
ПЛАЗМЫ В ПРИСУТСТВИИ ВЫСОКОЭНЕРГЕТИЧНОГО ЭЛЕКТРОННОГО ПУЧКА
А.A. Бизюков, К.Н. Середа, A.Д. Чибисов
Изучена зависимость потенциала макрочастицы в пучково-плазменной системе от ее параметров и
характеристик макрочастицы. Моделирование процесса зарядки проводилось в приближении орбитальной
модели движения ионов и электронов плазмы, а также электронов пучка. Исследовано влияние электронной
эмиссии с макрочастиц, разогретых до высоких температур, на величину потенциала c учетом ограничения
эмиссионного электронного тока собственным объемным зарядом.
ПРОЦЕСИ ЗАРЯДКИ МЕТАЛЕВИХ МАКРОЧАСТИНОК В НИЗЬКОТЕМПЕРАТУРНІЙ ПЛАЗМІ
В ПРИСУТНОСТІ ВИСОКОЕНЕРГЕТИЧНОГО ЕЛЕКТРОННОГО ПУЧКА
О.A. Бізюков, К.М. Середа, О.Д. Чибісов
Вивчено залежність потенціалу макрочастинки в пучково-плазмовій системі від її параметрів та
характеристик макрочастинки. Моделювання процесу зарядки проводилося в наближенні орбітальної моделі
руху іонів й електронів плазми, а також електронів пучка. Досліджено вплив електронної емісії з мікрочасток,
розігрітих до високих температур, на величину потенціалу з урахуванням обмеження емісійного електронного
струму власним об'ємним зарядом.
109
|
| id | nasplib_isofts_kiev_ua-123456789-90891 |
| institution | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| issn | 1562-6016 |
| language | English |
| last_indexed | 2025-12-07T18:37:10Z |
| publishDate | 2011 |
| publisher | Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| record_format | dspace |
| spelling | Bizyukov, A.A. Sereda, K.N. Chibisov, A.D. 2016-01-05T18:24:42Z 2016-01-05T18:24:42Z 2011 Charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam / A.A. Bizyukov, K.N. Sereda, A.D. Chibisov // Вопросы атомной науки и техники. — 2011. — № 1. — С. 107-109. — Бібліогр.: 6 назв. — англ. 1562-6016 PACS: 52.40.Hf https://nasplib.isofts.kiev.ua/handle/123456789/90891 The dependences of potential of macroparticle from the parameters and characteristics of plasma-beam system are
 studied. The modeling of charging processes of the macroparticles in approach of ions and electrons orbit motion
 limited theory made. The effect of electron emission from macroparticle has been investigated taking into account the
 space charge on potential of macroparticle. Вивчено залежність потенціалу макрочастинки в пучково-плазмовій системі від її параметрів та
 характеристик макрочастинки. Моделювання процесу зарядки проводилося в наближенні орбітальної моделі
 руху іонів й електронів плазми, а також електронів пучка. Досліджено вплив електронної емісії з мікрочасток,
 розігрітих до високих температур, на величину потенціалу з урахуванням обмеження емісійного електронного
 струму власним об'ємним зарядом. Изучена зависимость потенциала макрочастицы в пучково-плазменной системе от ее параметров и
 характеристик макрочастицы. Моделирование процесса зарядки проводилось в приближении орбитальной
 модели движения ионов и электронов плазмы, а также электронов пучка. Исследовано влияние электронной
 эмиссии с макрочастиц, разогретых до высоких температур, на величину потенциала c учетом ограничения
 эмиссионного электронного тока собственным объемным зарядом. en Національний науковий центр «Харківський фізико-технічний інститут» НАН України Вопросы атомной науки и техники Низкотемпературная плазма и плазменные технологии Charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam Процеси зарядки металевих макрочастинок в низькотемпературній плазмі в присутності високоенергетичного електронного пучка Процессы зарядки металлических макрочастиц низкотемпературной плазмы в присутствии высокоэнергетичного электронного пучка Article published earlier |
| spellingShingle | Charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam Bizyukov, A.A. Sereda, K.N. Chibisov, A.D. Низкотемпературная плазма и плазменные технологии |
| title | Charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam |
| title_alt | Процеси зарядки металевих макрочастинок в низькотемпературній плазмі в присутності високоенергетичного електронного пучка Процессы зарядки металлических макрочастиц низкотемпературной плазмы в присутствии высокоэнергетичного электронного пучка |
| title_full | Charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam |
| title_fullStr | Charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam |
| title_full_unstemmed | Charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam |
| title_short | Charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam |
| title_sort | charging processes of metal macroparticles in the low-temperature plasma at presence of high-energy electron beam |
| topic | Низкотемпературная плазма и плазменные технологии |
| topic_facet | Низкотемпературная плазма и плазменные технологии |
| url | https://nasplib.isofts.kiev.ua/handle/123456789/90891 |
| work_keys_str_mv | AT bizyukovaa chargingprocessesofmetalmacroparticlesinthelowtemperatureplasmaatpresenceofhighenergyelectronbeam AT seredakn chargingprocessesofmetalmacroparticlesinthelowtemperatureplasmaatpresenceofhighenergyelectronbeam AT chibisovad chargingprocessesofmetalmacroparticlesinthelowtemperatureplasmaatpresenceofhighenergyelectronbeam AT bizyukovaa procesizarâdkimetalevihmakročastinokvnizʹkotemperaturníiplazmívprisutnostívisokoenergetičnogoelektronnogopučka AT seredakn procesizarâdkimetalevihmakročastinokvnizʹkotemperaturníiplazmívprisutnostívisokoenergetičnogoelektronnogopučka AT chibisovad procesizarâdkimetalevihmakročastinokvnizʹkotemperaturníiplazmívprisutnostívisokoenergetičnogoelektronnogopučka AT bizyukovaa processyzarâdkimetalličeskihmakročasticnizkotemperaturnoiplazmyvprisutstviivysokoénergetičnogoélektronnogopučka AT seredakn processyzarâdkimetalličeskihmakročasticnizkotemperaturnoiplazmyvprisutstviivysokoénergetičnogoélektronnogopučka AT chibisovad processyzarâdkimetalličeskihmakročasticnizkotemperaturnoiplazmyvprisutstviivysokoénergetičnogoélektronnogopučka |