On the synthesis and processing of nanoparticles by plasmas
A gas aggregation system combined with a magnetron discharge is used to produce nanoparticles (NPs) from metal targets. Here, we presents an overview of the role of different parameters in the TiOx NP synthesis and available challenges in this technique. Particularly, considering the role of duty...
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Національний науковий центр «Харківський фізико-технічний інститут» НАН України
2016
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| Цитувати: | On the synthesis and processing of nanoparticles by plasmas / Amir Mohammad Ahadi,Thomas Strunskus, Oleksandr Polonskyi, Thomas Trottenberg,Holger Kersten , Franz Faupel // Вопросы атомной науки и техники. — 2016. — № 6. — С. 173-178. — Бібліогр.: 19 назв. — англ. |
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irk-123456789-1154442017-04-05T03:02:35Z On the synthesis and processing of nanoparticles by plasmas Ahadi, Amir Mohammad Strunskus, Thomas Polonskyi, Oleksandr Trottenberg, Thomas Kersten, Holger Faupel, Franz Low temperature plasma and plasma technologies A gas aggregation system combined with a magnetron discharge is used to produce nanoparticles (NPs) from metal targets. Here, we presents an overview of the role of different parameters in the TiOx NP synthesis and available challenges in this technique. Particularly, considering the role of duty cycle in the TiOx NP formation at pulsed DC regime indicates that only at a certain duty cycle (for the given condition) a stable NP generation can be achieved. Furthermore, the critical role of oxygen (as a reactive admixture gas) in launching and controlling of the NP synthesis process is studied in detail. Employing an RF hollow electrode discharge for processing of silver NPs leads to charging of most of the NPs, and surprisingly, we found that at high RF plasma powers the contribution of charged NPs in the primary NP beam vanished in the treated beam deposition. Использование систем агрегации газа и магнетронного разряда позволяет получать наночастицы (НЧ) из металлических мишеней. Представлен обзор различных параметров, влияющих на синтез TiOx НЧ, и существующих проблем этого метода. В частности, влияние рабочего цикла на формирование TiOx НЧ в импульсном DC-режиме указывает на то, что стабильное образование НЧ может быть достигнуто только в определённом рабочем цикле (при данных условиях). Кроме того, детально изучена ключевая роль кислорода (в качестве газовой реактивной добавки) в инициировании и контроле процесса синтеза НЧ. Использование ВЧ-разряда с полым электродом для обработки НЧ серебра приводит к зарядке большинства НЧ. Также показано, что в режимах с высокой ВЧ-мощностью, вводимой в плазму, заражённые частицы в первичном пучке НЧ не вносят вклад в осаждение. Використання систем агрегації газу і магнетронного розряду дозволяє отримувати наночастинки (НЧ) з металевих мішеней. Представлено огляд впливу різних параметрів на синтез НЧ TiOx та існуючих проблем цього методу. Зокрема, вплив робочого циклу на формування НЧ TiOx в імпульсному DC-режимі вказує на те, що стабільне утворення НЧ може бути досягнуто тільки в певному робочому циклі (за данних умов). Крім того, детально вивчена ключова роль кисню (в якості газової реактивної добавки) у ініціюванні та контролі процесу синтезу НЧ. Використання ВЧ-розряду з порожнім електродом для обробки НЧ срібла призводить до зарядження більшості НЧ. Також показано, що в режимах з високою ВЧ-потужністю, що вводиться в плазму, заряджені частинки в первинному пучку НЧ не мають впливу на осадження. 2016 Article On the synthesis and processing of nanoparticles by plasmas / Amir Mohammad Ahadi,Thomas Strunskus, Oleksandr Polonskyi, Thomas Trottenberg,Holger Kersten , Franz Faupel // Вопросы атомной науки и техники. — 2016. — № 6. — С. 173-178. — Бібліогр.: 19 назв. — англ. 1562-6016 nished in the treated beam deposition. P http://dspace.nbuv.gov.ua/handle/123456789/115444 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| language |
English |
| topic |
Low temperature plasma and plasma technologies Low temperature plasma and plasma technologies |
| spellingShingle |
Low temperature plasma and plasma technologies Low temperature plasma and plasma technologies Ahadi, Amir Mohammad Strunskus, Thomas Polonskyi, Oleksandr Trottenberg, Thomas Kersten, Holger Faupel, Franz On the synthesis and processing of nanoparticles by plasmas Вопросы атомной науки и техники |
| description |
A gas aggregation system combined with a magnetron discharge is used to produce nanoparticles (NPs) from
metal targets. Here, we presents an overview of the role of different parameters in the TiOx NP synthesis and
available challenges in this technique. Particularly, considering the role of duty cycle in the TiOx NP formation at
pulsed DC regime indicates that only at a certain duty cycle (for the given condition) a stable NP generation can be
achieved. Furthermore, the critical role of oxygen (as a reactive admixture gas) in launching and controlling of the
NP synthesis process is studied in detail. Employing an RF hollow electrode discharge for processing of silver NPs
leads to charging of most of the NPs, and surprisingly, we found that at high RF plasma powers the contribution of
charged NPs in the primary NP beam vanished in the treated beam deposition. |
| format |
Article |
| author |
Ahadi, Amir Mohammad Strunskus, Thomas Polonskyi, Oleksandr Trottenberg, Thomas Kersten, Holger Faupel, Franz |
| author_facet |
Ahadi, Amir Mohammad Strunskus, Thomas Polonskyi, Oleksandr Trottenberg, Thomas Kersten, Holger Faupel, Franz |
| author_sort |
Ahadi, Amir Mohammad |
| title |
On the synthesis and processing of nanoparticles by plasmas |
| title_short |
On the synthesis and processing of nanoparticles by plasmas |
| title_full |
On the synthesis and processing of nanoparticles by plasmas |
| title_fullStr |
On the synthesis and processing of nanoparticles by plasmas |
| title_full_unstemmed |
On the synthesis and processing of nanoparticles by plasmas |
| title_sort |
on the synthesis and processing of nanoparticles by plasmas |
| publisher |
Національний науковий центр «Харківський фізико-технічний інститут» НАН України |
| publishDate |
2016 |
| topic_facet |
Low temperature plasma and plasma technologies |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/115444 |
| citation_txt |
On the synthesis and processing of nanoparticles by plasmas / Amir Mohammad Ahadi,Thomas Strunskus, Oleksandr Polonskyi, Thomas Trottenberg,Holger Kersten
, Franz Faupel // Вопросы атомной науки и техники. — 2016. — № 6. — С. 173-178. — Бібліогр.: 19 назв. — англ. |
| series |
Вопросы атомной науки и техники |
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2025-07-08T08:47:21Z |
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2025-07-08T08:47:21Z |
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| fulltext |
LOW TEMPERATURE PLASMA AND PLASMA TECHNOLOGIES
ISSN 1562-6016. ВАНТ. 2016. №6(106)
PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. 2016, № 6. Series: Plasma Physics (22), p. 173-178. 173
ON THE SYNTHESIS AND PROCESSING OF NANOPARTICLES
BY PLASMAS
Amir Mohammad Ahadi,
1,2
Thomas Strunskus,
1
Oleksandr Polonskyi,
1
Thomas Trottenberg,
3
Holger Kersten
3
, Franz Faupel
1
1
Institute for Materials Science, University of Kiel, Germany;
2
Department of Physics, Shahid Chamran University of Ahvaz, Ahvaz, Iran;
3
Institute of Experimental and Applied Physics, University of Kiel, Germany
E-mail: ahadi.am@gmail.com
A gas aggregation system combined with a magnetron discharge is used to produce nanoparticles (NPs) from
metal targets. Here, we presents an overview of the role of different parameters in the TiOx NP synthesis and
available challenges in this technique. Particularly, considering the role of duty cycle in the TiOx NP formation at
pulsed DC regime indicates that only at a certain duty cycle (for the given condition) a stable NP generation can be
achieved. Furthermore, the critical role of oxygen (as a reactive admixture gas) in launching and controlling of the
NP synthesis process is studied in detail. Employing an RF hollow electrode discharge for processing of silver NPs
leads to charging of most of the NPs, and surprisingly, we found that at high RF plasma powers the contribution of
charged NPs in the primary NP beam vanished in the treated beam deposition.
PACS: 52.77-j, 81.15.cd, 81.16.-c
INTRODUCTION
Synthesis and processing of nanoparticles (NPs) for
different applications have received numerous attentions
during the last years due to the extraordinary
characteristics of NPs and the exclusive role of this type
of materials in tuning the properties of advanced
functional materials [1]. Although in advanced
technologies, plasmas with different configurations are
frequently employed for various aims, due to the
complexity of the phenomena, several aspects of the
observed behaviour in the NP generation process and
materials treatment are still unexplored.
Controlled synthesis of NPs is an interesting
challenge in nanotechnology. Among several plasma
based techniques for NPs production [2], a gas
aggregation source (GAS) combined with magnetron
sputtering is one of the most desired systems to generate
NPs from various materials [3-6]. Adjusting the NPs
properties by tuning the operating conditions is the
biggest advantage of this method.
Due to the interesting chemical activities and a wide
variety of applications [7, 8], many researchers have
focused on understanding and optimizing the synthesis
process of titanium based NPs by the gas phase route
[5], [9-12]. Previously, Marek et al. [10] showed that
adding oxygen (as a reactive admixture) to the
aggregation zone can considerably accelerate the TiOx
NPs synthesis process. Next, experiments by Peter et al.
[11] approved that the NP generation from a pure Ti
target is impossible by the conventional DC sputtering
in a pure noble gas atmosphere. Furthermore, in the
given conditions, the TiOx NPs generation is launched
only when the oxygen admixture is selected from a
certain range. Recently, we have indicated that by
adjusting the amount of oxygen admixture, a stabilized
TiOx NPs generation rate for a long term can be
achieved [12]. The physics beyond the synthesis and
also the stabilized generation of TiOx NPs is very
complicated. Here, we overview the key role of the
plasma species and also the discharge properties in the
NP synthesis from a reactive metal.
In most cases, the synthesized NPs should be treated
by a proper technique in a characterized environment to
show the desired properties. Hence, understanding the
interactions between NPs and processing medium is
very important and plays a crucial role in the fabrication
of advanced nanomaterials and also adjusting of their
properties. Nowadays, modification of physical and
chemical properties of NPs is one of the biggest
challenges in technological breakthroughs [13]. To
avoid undesired effects and also complexity, the NP
modification should be performed in a separate
environment. However, when a complex medium, such
as plasma, is employed for processing, interpreting the
observed phenomenon will often be complicated.
Nevertheless, the outstanding properties of plasmas with
different configurations could convince many
researchers to employ them for processing a wide range
of materials. Here, we investigate the interactions
between an RF hollow discharge and a metal NPs beam
produced by the GAS. For this purpose, an extra plasma
system was added to the setup and the titanium target
was replaced by a silver target.
1. EXPERIMENTAL
The experimental setup used here was already
described in previous articles [12, 14, 15]. A home-
constructed GAS combined with a 2 inch planar
magnetron was applied to generate NPs from a silver
and/or titanium target. Argon was used as a working
gas, while in case of the titanium target a small amount
of oxygen (as reactive admixture) was added to the
aggregation chamber. The GAS was connected to the
deposition chamber via an orifice, 3 mm in diameter.
The pumping system (includes a turbo molecular pump
supported by a scroll pump) connected to the main
chamber reduced the whole system pressure to 10
-5
Pa
as base pressure [12]. To process the formed Ag NPs, a
fairly small hollow electrode working at low pressures
and RF regime was lastly installed in the main chamber
[14]. It was connected to the GAS through an electrical
deflector. The deflector system includes two plate
mailto:ahadi.am@gmail.com
174 ISSN 1562-6016. ВАНТ. 2016. №6(106)
electrodes with a small rectangular slit on each. These
electrodes were connected to the separate DC power
supplies with opposite polarities at a fixed voltage
(70 V) to remove all charged NPs from the NP beam.
More details of the used experimental setup can be
found in Ref. [15].
2. RESULTS AND DISCUSSION
For the study of the stability of TiOx NP generation,
a set of experiments was performed by running a DC
magnetron discharge in the GAS to generate NPs from a
pure titanium target. To get comparable results, all
experiments were started with the pre-cleaning process
by running the discharge for several minutes in a pure
argon atmosphere to remove all impurities in the system
(mostly from the target surface). The pre-cleaning was
continued as long as a certain magnetron bias voltage
was recovered at a given pressure (50 Pa). After the pre-
cleaning process (at t = 0), a small amount of oxygen
admixture was added to the GAS, and the NP deposition
rate (D.R.) was measured by a quartz microbalance
monitor (QCM) which was mounted in the deposition
chamber. Primary findings at DC regime showed that
only under a certain oxygen admixture a highly stable
TiOx NP generation can be achieved at the relatively
low pressure (50 Pa) [12].
Fig. 1. Evolution of TiOx NPs deposition at different
pressures after optimizing the oxygen admixtures. Only
at low pressure (50 Pa) a highly stable deposition rate
was found [12]
The oxygen admixture is needed to increase the
bonding energy of the seeds by changing their chemistry
[11]. On the other hand, oxygen can reduce the
sputtering rate by forming (and then developing) the
poisoned area on the target. Competition between these
two mechanisms determines the evolution of the TiOx
NP generation rate in the GAS.
Switching to higher pressure not only shifts the
range of working oxygen admixture to a lower level, but
also can dramatically decelerate (and finally suppress)
the NP formation process by reducing the sputtering rate
(Fig. 1). In the high pressure regime, returning many of
individual sputtered atoms to the target surface, after
oxidation in volume (due to the collisions with the
background gas), is the main factor to accelerate the
poisoning process. Therefore, the NP D.R. drops to zero
(or very low level) after increasing for some minutes.
As already seen, the oxygen admixture plays an
important role in controlling of different mechanisms in
the GAS. Thus, considering the role of reactive species
in different processes is very instructive. Particularly, in
the current research, understanding the channels of
oxygen consumption in the GAS is of interest. When
oxygen is injected into the chamber, it starts to diffuse
into the volume. During this process, some of the
oxygen species can meet the sputtered atoms and bond
to them. These oxidized species (metal oxide molecules)
are the main constitutes for the nucleation and growth of
NPs in the GAS [13]. The rate of oxygen consumption
by free sputtered atoms depends on the concentration of
oxygen species, the density of free sputtered atoms, and
specially the diffusion rate in the buffer gas.
Furthermore, the flux of oxygen, the working pressure,
and the temperature are considered as important
parameters which can indirectly influence on the rate of
oxygen-sputtered atom reactions. The non-reacted
oxygen particles in the above mechanism can reach the
walls and also the target surface. Those oxygen particles
that reach the walls can be bound by the available metal
atoms on the GAS walls through chemical reactions, or
stick to the walls individually. Furthermore, the arrived
oxygen particles on the target can react with upper
atoms of the target surface and poison the target by
forming a dielectric oxide layer on it. Finally, the
remaining oxygen, which does not participate in the
above processes, can escape from the GAS via the small
orifice.
The rate of oxygen consumption by each mechanism
depends on how the oxygen is introduced into the GAS.
Since in the used setup the gases stream into the GAS
from a channel near the target, the poisoning process is
more pronounced in a short period after the oxygen
injection.
A study on each possible scenario of oxygen
consumption provides useful knowledge to understand
the physics of synthesis in the GAS. As it was
previously addressed in detail [5, 12] the escaped
oxygens from the GAS can be monitored by a mass
spectrometer in the deposition chamber. The mass
spectrometer signals clearly manifest the evolution of
the oxygen consumption in the GAS [12]. In-situ
measurement of chemical composition of the formed
NPs can give some information about the content of
oxygen consumed in the clustering process [5].
Furthermore, the evolution of the bias voltage (of the
magnetron discharge) is proportional to the
development of the poisoned regions on the target [12].
Fig. 2 displays a chart of possible scenarios for oxygen
in a GAS. Although the highlighted green route is the
desired scenario that leads to the NP generation, the
optimized NP formation can be achieved only by
controlling all scenarios.
It is well known [17] that forming of poisoned areas
on the target reduces the active area in the sputtering
process by creating a strong local electric field in the
poisoned regions. For solving this problem, the pulsed
DC sputtering was developed [16]. Preliminary
О2 = 0.080 sccm
O2 = 0.040 sccm
O2 = 0.030 sccm
ISSN 1562-6016. ВАНТ. 2016. №6(106) 175
experiments confirmed that switching to the pulsed DC
regime can significantly increase the rate of TiOx NP
generation [17] which is promising for stabilizing the
NP formation at high pressures. The frequency and the
duty cycle of the pulse are crucial parameters in this
regime [5], [16]. They should be adjusted in a way that
the electrons can neutralize the total charge on the
target, and also the strength of the delivered power
should be sufficient to remove the poisoned area on the
target surface.
To optimize the pulsing parameters for getting the
stabilized TiOx NP generation, several experiments
were performed at different operating conditions. This
part is devoted to study the influence of the duty cycle
on the synthesis process at 100 Pa working pressure,
while the oxygen admixture and frequency are kept
constant at 0.055 sccm and 40 kHz, respectively.
Fig. 2. A schematic chart of different possibilities for oxygen consumption in the GAS. The green line is the favored
route leading to the NP generation
As shown in Fig. 3, immediately after oxygen injection
to the chamber no deposition was recorded. As found in
the DC regime, during a short period after oxygen
injection, most of the oxygen is absorbed by the highly
reactive pure titanium atoms on the target and the walls
of the GAS. This prevents forming sufficient seeds in
the volume to launch the TiOx NP. Thus, the D.R. of
NPs remains at the zero level during a short period after
the oxygen injection. As soon as the gettering process
ceases, some of the oxygen species can participate in the
clustering process by oxidation of the sputtered atoms.
However, sputtering the oxide species during the
plasma on period has a main contribution in launching
the NP synthesis in this regime. According to the
obtained data (see Fig. 3), only at a certain duty cycle
(50 % for the given operating conditions), the stabilized
TiOx NP formation was achieved. This means, only at
unique operating parameters the area of the poisoned
zones on the target (and then the sputtering rate) is
constant. In this case, the rate of the poisoning process
and the rate of the cleaning process in the plasma on
period are in equilibrium.
Switching to the lower duty cycle led to an unstable
D.R.. At this condition, a shorter plasma on period
increases the power density which improves the
sputtering rate during the plasma on period.
Additionally, a longer plasma off period results in more
oxide formation on the target. These oxide species have
an opportunity to participate in the NP formation
process after sputtering off in the next plasma on period.
At such a duty cycle, the cleaning process overcomes
the poisoning process. Higher seed density accelerates
the NP formation rate, which shifts the knee of the D.R.
to a higher level. However, by continuous surface
cleaning, the target gradually turns to a pure metal
target. This increases the number of pure Ti atoms in the
volume, and then the NP nucleation process will be
decelerated (due to low bonding energy of pure Ti
atoms). In the opposite direction, by switching to a
higher duty cycle, the NP D.R. falls to the zero level
after initial increasing. In this case, the longer plasma
on period reduces the power density which leads to a
lower sputtering yield. On the other hand, a completely
oxidized TiO2 layer has a tendency to release oxygen
under energetic ion bombardment and convert to a
titanium sub-oxide layer [18], [19]. Therefore, in
reactive sputtering of titanium, the energetic impacting
ions have a critical role in the cleaning process and
subsequently, in increasing the conductivity of the target
surface. At a lower power density, the magnetron
discharge includes less energetic ions which reduces the
rate of the cleaning process. Additionally, a shorter
176 ISSN 1562-6016. ВАНТ. 2016. №6(106)
plasma off period reduces the available time for the
incoming electrons (to the target surface) to neutralize
the ions on the target. Both above mentioned factors
decrease the seed density continuously. Then, after
several cycles, the number density of seeds in the
volume cannot meet the supersaturation condition, and
the NP formation process will be totally suppressed. As
it recently has been reported, a similar behavior can be
found for the repetition frequency [5].
Fig. 3. Evolution of TiOx NPs deposition at different
duty cycles in the pulsed DC regime. The repetition
frequency and oxygen admixture were fixed at 40 kHz
and 0.055 sccm, respectively
The role of oxygen in the NP synthesis process in
the pulsed DC regime was previously studied [5].
Several experiments confirmed that a small change in
oxygen admixture does not disturb the stability of the
TiOx NP deposition, but can significantly change the
size of the formed NPs in a nonlinear way. However,
the physics of this behavior is not understood yet.
In the last section of this work, a fairly small RF
hollow electrode working in the low pressure regime
was added to the setup to modify the NPs before
deposition. The target was also replaced by a silver
target to be able to have a stable NP generation in the
conventional DC regime. The hollow electrode was
installed in the deposition chamber and connected to the
GAS via an electric deflector. The deflector was
employed to remove all the charged NPs coming from
the GAS [12]. Due to the novelty of the hollow
electrode geometry, a set of plasma diagnostics was
used to characterize the ignited RF discharge at different
operating conditions. Details of the obtained data have
been reported by Ahadi et al. [14]. The RF plasma
interestingly resembles a DC hollow cathode discharge.
Furthermore, the high electron density at different
operating conditions promises to be a suitable system
for different materials processings. Previous
investigations [15] showed that the geometry of the
deposited spot varied with the RF power. Furthermore,
the lateral size distribution of Ag NPs in the beam
changes with plasma power. These observations can be
explained by the charging of NPs in the plasma and
trapping of the negatively charged NPs in the plasma
volume. Additionally, the results clearly indicated that
most of the NPs are negatively charged by the plasma,
while the contribution of the positive NPs increases with
increasing the RF power [15].
Here, we explored the influence of the hollow
electrode discharge (with different powers at fixed
pressure (2 Pa)) on the D.R. of Ag NPs generated by the
GAS operated at 200 Pa. The measurements were
performed two times, once for a pure neutral NP beam
(after purification by the deflector) and once for the
primary NP beam generated by the GAS (without
purification). The obtained data are summarized in
Fig. 4. As a general trend, treatment by the RF plasma
significantly reduces the NP deposition (a sharp drop in
the curve). At low RF powers, this reduction is more
pronounced, and the D.R. reduces more than one order
of magnitude in the presence of the RF discharge.
Increasing the plasma power, increases the D.R.
gradually, and finally the rate of NP deposition reaches
a stable level. Losing NPs in the plasma volume
(particularly at low applied powers) and the electrostatic
repulsion force between NPs after charging by plasma
can explain this reduction. Moreover, increasing the
plasma bias voltage by the plasma power [14] enhances
the trapping of negatively charged NPs in the bulk
plasma, which results in a greater D.R. at higher RF
power. As expected, the D.R. of the pure neutral NP
beam (blue markers) at very low powers is lower than
the D.R. of the unfiltered beam (black markers).
However, by increasing the RF power this difference
becomes smaller, and eventually at high powers an
identical D.R. was found in both cases. In other words,
the existence of the charged NPs in the unfiltered beam
was concealed by the RF discharge at high applied
powers. Reflection of the negatively charged NPs by the
plasma sheath (which can be changed by power) and
then losing the positively charged NPs in the RF plasma
volume, can explain the observed behavior. However,
more experiments should be done to clarify the physics
behind this trend.
Fig. 4. The deposition rate of the filtered (blue) and
unfiltered (black) Ag NPs after processing by a hollow
electrode discharge at different powers
CONCLUSIONS
Synthesis and deposition of oxide metal NPs were
investigated experimentally by employing a GAS
combined with reactive DC and/or pulsed DC
ISSN 1562-6016. ВАНТ. 2016. №6(106) 177
magnetron sputtering. The role of reactive gas
admixture, pressure, and pulsing parameters on NP
formation was studied in detail. In the DC regime, due
to the continuous enlarging of the poisoned area at high
pressures, the highly stabilized TiOx NP generation was
found only at low pressure (50 Pa). The analyzed data
demonstrated that, at given conditions, the stable NP
production is limited to a narrow range of oxygen
admixture and certain pulsing parameters.
Considering the interaction between Ag NPs and an
RF hollow electrode discharge showed that most of the
NPs are negatively charged in the plasma. The NP
deposition was considerably reduced under plasma
treatment. Furthermore, the losing of charged NPs from
the unfiltered beam is more pronounced in the high
plasma power regime.
ACKNOWLEDGEMENTS
A.M. Ahadi is grateful to the Iran Ministry of sciences
for financial support. This work was supported by the
German Research Foundation (DFG) within the
framework of the Collaborative Research Center SFB
TR24-B13. We would also like to thank Stefan Rehders
for the technical construction of the cluster source and
hollow electrode.
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Article received 12.10.2016
178 ISSN 1562-6016. ВАНТ. 2016. №6(106)
СИНТЕЗ И ОБРАБОТКА НАНОЧАСТИЦ С ПОМОЩЬЮ ПЛАЗМЫ
Amir Mohammad Ahadi,
Thomas Strunskus, Oleksandr Polonskyi, Thomas Trottenberg,
Holger Kersten, Franz Faupel
Использование систем агрегации газа и магнетронного разряда позволяет получать наночастицы (НЧ) из
металлических мишеней. Представлен обзор различных параметров, влияющих на синтез TiOx НЧ, и
существующих проблем этого метода. В частности, влияние рабочего цикла на формирование TiOx НЧ в
импульсном DC-режиме указывает на то, что стабильное образование НЧ может быть достигнуто только в
определённом рабочем цикле (при данных условиях). Кроме того, детально изучена ключевая роль
кислорода (в качестве газовой реактивной добавки) в инициировании и контроле процесса синтеза НЧ.
Использование ВЧ-разряда с полым электродом для обработки НЧ серебра приводит к зарядке большинства
НЧ. Также показано, что в режимах с высокой ВЧ-мощностью, вводимой в плазму, заражённые частицы в
первичном пучке НЧ не вносят вклад в осаждение.
СИНТЕЗ І ОБРОБКА НАНОЧАСТИНОК ЗА ДОПОМОГОЮ ПЛАЗМИ
Amir Mohammad Ahadi,
Thomas Strunskus, Oleksandr Polonskyi, Thomas Trottenberg,
Holger Kersten, Franz Faupel
Використання систем агрегації газу і магнетронного розряду дозволяє отримувати наночастинки (НЧ) з
металевих мішеней. Представлено огляд впливу різних параметрів на синтез НЧ TiOx та існуючих проблем
цього методу. Зокрема, вплив робочого циклу на формування НЧ TiOx в імпульсному DC-режимі вказує на
те, що стабільне утворення НЧ може бути досягнуто тільки в певному робочому циклі (за данних умов).
Крім того, детально вивчена ключова роль кисню (в якості газової реактивної добавки) у ініціюванні та
контролі процесу синтезу НЧ. Використання ВЧ-розряду з порожнім електродом для обробки НЧ срібла
призводить до зарядження більшості НЧ. Також показано, що в режимах з високою ВЧ-потужністю, що
вводиться в плазму, заряджені частинки в первинному пучку НЧ не мають впливу на осадження.
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