Vzdělávání výzkumných pracovníků v Regionálním …fyzika.upol.cz/cs/system/files/seminare/2011-01-28...Vzdělávání výzkumných pracovníků v Regionálním centru pokročilých

Vzdělávání výzkumných pracovníků v Regionálním centru pokročilých

technologií a materiálůreg. č.: CZ.1.07/2.3.00/09.0042

Tento projekt je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.

Institute of Physics ASCR Na Slovance 2, 182 21 Prague 8, Czech Republic

Fyzikální ústav, v.v.i., AVČR, Na Slovance 2, 182 21 Praha 8Sekce optikaOddělení nízkoteplotního plazmatuZdeněk Hubičkavědečtí a odborní pracovníci: Martin Čada, Vítěslav Straňák, Petr Adámek, Oleksander Churpita, Jiří Olejníček, Alexander Tarasenko, Lubomír JastrabíkŠtěpán Kment, Michal Kohout, doktoranti: Jan Klusoň, Pavel Dytrych

další spolupracovníci: A. Deyneka, D. Chvostová, M. Tichý, K. Jurek, V. Valvoda, R. Hippler, P. Klusoň, G. Suchaneck, I. Gregora, Z. Bryknar

Pokročilé zdroje nízkoteplotního plazmatu pro technologické procesy

• Tento projekt je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.

Low temperature plasma for deposition of thin films

typical properties:electron temperature Te ∼ 10 000 – 50 000 K ion temperature Ti ~ 300-800 Ktemperature of neutrals Tn ~ 300-800 K

-

-far from thermodynamic equilibrium

-sometimes electron distribution function is not Maxwellian

electron and ion concentration ne,i = 109 – 1013 cm-3

working gas pressures p ~ 0.05 - 105 Pa

Francis F. Chen, Jane P. Chang, Lecture Notes onPRINCIPLES OF PLASMA PROCESSING, Plenum/Kluwer Publishers2002

mass of electron: me = 9.1 • 10-31 kg mass of argon atom or ion Ar+ MAr

+ =6.64 • 10-26 kg

Elastic: momentum is redistributed between particlesand the total kinetic energy remains unchanged, e.g.e− fast + Aslow → e− less fast + A less slow.

•Lighter particles (m) cannot lose much energy elasticallyto heavier particles (M)—at best a fraction ≈ 2m/M,nevertheless, substantial changes in momentum occur(cf tennis).

•A moving particle on striking elastically a stationaryone of equal mass head-on can transfer all of its kineticenergy (cf billiards).

Inelastic: momentum is redistributed between particlesbut a fraction of the initial kinetic energy is transferredto internal energy in one or more of the particles (i.e.excited states or ions are formed), e.g.e− fast + A → e− slower + A∗

→ e− slower + A+ + e−.

•Lighter particles can lose virtually all their kinetic energythrough inelastic collisions with heavier objects (cfsandblasting).

•Equal mass particles can lose no more than half theirkinetic energy inelastically on collision (cf ion impactionization).

Superelastic: a third class also needs to be anticipated—here there is more kinetic energy after the collision.Momentum is conserved and internal energy in theparticles entering into a collision is transferred intokinetic energy, e.g.

A∗ slow + B slow → A faster + B faster .

Interakce plazmatu se stěnou

Examples of plasma parameters

Examples of electron energy probability function in low temperature plasma

P. Virostko, et al, Contributions to Plasma Physics, 46, (2006) 455-460.

Capacitive RF discharge (RF diode system)

Model of capacitive RF discharge

Model of capacitive RF discharge-potential distribution

Experimental study of symmetric capacitive discharge at 13.56 MHz in argon (Godyak 1991)

discharge length=6.7 cm diameter of electrodes=14.3 cm

Experimental study of symmetric capacitive discharge at 13.56 MHz in argon


Experimental study of symmetric capacitive discharge at 13.56 MHz in argon


depozice amorfního křemíkuSi:H pomocí rozkladu SiH4

v kapacitním RF výboji

Aplikace symetrického kapacitního výboje-nízkotlaká depozice PECVD- rozklad par prekurzorů je zajištěn pomocí nízkoteplotního plazmatu

Capacitive RF plasma sources fundamentals

Asymmetric configuration

the area of driven electrode is much smaller than the grounded one the capacitive impedance XC1 of the sheet at driven electrode is much higher than the capacitive impedance XC2 of the sheet at grounded electrode ⇒ much higher RF voltage URF1 on XC1 than RF voltage URF2 on XC2. We can write ( J.H. Keller, W.B. Pennebacker, IBM J. Res. Develop. 23 (1979) 3. )

k is Botzmann constant, Te electron temperature, Mi , me mass of ion and electron respectively, e-elementary charge and Io is zero order modified Bessel function.

because URF1 >>URF2 then Ub1>>Ub2

Ub1 is usually in the range of Ub1≈ 100V-1kV.

+= )(ln

2ln 0

e

RFi

e

iebi kT

eUImM

ekTU

π

RF sputtering advantages:

-Electrodes (active electrode) can be fully covered by dielectric target which will be sputtered (for example SiO2 , TiO2, SrTiO3, BaTiO3, PZT targets-suppressed arcing

RF sputtering disadvantages: more technically difficult RF interference limited size of target, etc..

RF magnetron sputtering (possible dielectric target)

Plasma etching

Plasma etching

Plasma etching with ion bombardment

High density plasma sources

-Limitations of capacitively coupled plasma sources led to the development of a new generation of low pressure high-density plasma sources-noncapacitive transfer of power to the plasma ⇒ low voltages across all plasma sheets- possibility of independent control of energy and magnitude of substrate ion flux

Examples of high density plasma sources

magnetic field multi-pole confinement

Inductively coupled plasma sources

-Driven frequencies are below self-resonant frequencies of coil. -very old type of discharge

Inductive coils are typically drive at or below 13.56 MHz.

Planar coil configuration of ICP

Nanostructures fabricated by plasma

N anos truc tures Prepared by P las ma Treatment of S olid Phas es

1) Metal Oxide Nanostructures by Oxygen-Plasma Treatment

M. Mozetic, U. Cvelbar, M. K. Sunkara, S. Vaddiraju, Adv. Mater. 2005, 17, 2138.U Cvelbar and M Mozetic, J. Phys. D: Appl. Phys. 40 (2007) 2300–2303

-Mozetic et al. prepared Nb2O 5 nanowires by O 2 plasma treating of Nb foils in a 27.12MHz ICP plasma. -The plasma was operated at a relatively low pressure of 100 Pa and a high power of 1.5kW

- O atoms recombination on the surface the Nb2O 5 nanowire structures were more favorable, compared to Nb2O 5 thin films, revealing potential applications in catalysis.

ICP plasma system for fabrication of Nb2O5 nanowires by O2 plasma treating of Nb foils in a 27.12MHz ICP plasma

M. Mozetic, U. Cvelbar, M. K. Sunkara, S. Vaddiraju, Adv. Mater. 2005, 17, 2138.U Cvelbar and M Mozetic, J. Phys. D: Appl. Phys. 40 (2007) 2300–2303

U Cvelbar and M Mozetic, J. Phys. D: Appl. Phys. 40 (2007) 2300–2303

-comparison of surfaces of pure Nb foil, thermally oxidized Nb foilAnd Nb foil treated by plasma

-The plasma characteristics were diagnosed to be weakly ionized but highly dissociated, i.e., dominated by oxygen atoms. The nanowire formation was attributed to the chemical effect rather than sputtering. A bottom-growth model was proposed to explain the growth of high-density Nb2O5 nanowires, since all Nb species arose fromthe Nb foil.

J ie Z heng , R ong Y ang , Lei X ie, J iang lan Qu, Y ang L iu, and X ing g uo Li, Adv. Mater. 2010, 22, 1451–1473

-The Nb-foil temperature during the plasma treatment was in the low-temperature range (50–300 oC) during the process. It is believed that the limited diffusion of Nb atoms on the surface resulted in the growth of the nanowire structure.

Uros Cvelbar, Kostya (Ken) Ostrikov and Miran Mozetic Nanotechnology 19 (2008) 405605 (7pp)

C dO nanos truc tures prepared by oxyg en IC P plas ma treatment

- The ICP oxygen plasma parameters were as follows: the electron temperature Te ∼ 3–5 eV, ion density ni ∼ 1015–1016 m−3, and neutral oxygen density nO ∼ 1020–1022 m−3. The molecular gas temperature Tg was in the range 300–450 K.

-High-purity (99.9%) cadmium foil of thickness 0.3 mm was exposed to inductively coupled oxygen plasma created in a low-pressure RF glow discharge


-when the equilibrium temperature is high (curve 1 in figure 2), the foil material is evaporated;

-when the surface temperature reaches the melting point of cadmium (594 K), pyramid-like nanostructures emerge as can be seen in figures 4 and 5; in this temperature range a thin surface layer of the cadmium foil experiences a phase transition from the solid to the liquid state;

-a flat-grained structure with small oxide grains and no clear nanostructures (e.g., nanobelts, nanowires or nanopyramids) is formed at lower equilibrium temperatures (300–400 K), see figure 3. For simplicity, we will further refer to the flat-grained structure as the flat oxide.

Comparison of growth modes for CdO pyramid-like nanostructures and flat-grained structure with small oxide grains and no clear nanostructures


- A prolonged exposure of the cadmium surface layer in the critical the solid–liquid (S–L) phase yields even larger pyramidal crystals of micrometer dimensions clearly seen in figure 5. Their growth is relatively fast and continues until the whole surface is covered (figure 5).


-The fabrication of pyramidal nanostructures is a three-dimensional (3D) process, in which nano-sized nuclei evolve into micron-sized objects as sketched in figure 6. Moreover, CdO crystals (S2 phase in the S1–L–S2 system, where S1 corresponds to the cadmium foil) grow from the S–L phase due to interactions of oxygen species with Cd foil which leads to the localized heating and melting of the surface material (stages I–II in figure 6).


-Direct growth of In2O3 nanowires was realized by oxygen plasma treatment of single-crystalline InAs wafers.

Growth of In2O 3 nanow ires rea lized by oxyg en pla s ma treatment

Li et al. Appl. Phys. Lett. 2005, 87, 143104.

-Electric-field-aligned growth of the In2O3 NWs was performed in a vacuum chamber with two planar electrodes and a disklike heater, as shown in Fig. 1.

-The InAs 100 substrate, coated with a 10 nm Au film as a catalyst, was put on the mica slice.-During the growth process, the pressure in the chamber was maintained at 50 Torr. Ar gas mixed with 0.08% O2 flowed into the chamber at the rate of 50 sccm.

-The temperature of the substrate increased to 480 °C in 3 min, and was kept for 1 min. In order to initiate plasma, a dc voltage of about 230 V was applied between two electrodes with a current of about 1.5 mA.

-The plasma was used to produce an electric field within the plasma sheath on the substrate to adjust the growth direction of the NWs.


-Since In2O3 was ionic oxide with high polarizability, the electric-field induced dipoles in the In2O3 NWs. The dipole moments in the NWs were along the NWs’ axes. When the NWs’ axes were not along the direction of the electric field, the electric field would apply torques on the dipole moments to rotate the NWs until they were along the direction of the electric field. Accordingly, the torques applied on the NWs prevented the direction of their growth from deviating from the direction of the electric field, resulting in the aligned growth of NWs.

-NWs were investigated by HRTEM, but no catalyst particles were found on the NW’s top.

-The In2O3 NWs growth might follow a base-growth model. At 480 °C, InAs decomposed into In and As, resulting in the formation of Au–In eutectic liquid nanoparticles. The In, on the surface of Au–In eutectic liquid nanoparticles, reacted with oxygen, forming In2O3 nucleus as the growth units of In2O3 NWs. More In atoms from the decomposed InAs substrate diffused into the Au–In liquid nanoparticles, leading to the growth of In2O3 NWs.

-The well-aligned In2O3 nanowires also exhibited promising field-emission properties.



-Figures 4a and 4b show high-resolution transmission electron microscope HRTEM images of single In2O3 NW with a diameter about 6 nm. The electron diffraction pattern Fig. 4c revealed that the NW was a single-crystalline phase and formed by the stacking of 200 planes along the 100 direction. This result was also confirmed by its magnified HRTEM image Fig. 4b, where the 0.503 nm spacing between adjacent lattice planes perpendicular to the growth direction corresponded to the distance between 200 lattice planes.

2) Nanostructures Prepared Through a Plasma Etching Mechanism

-The plasma treatment usually imposed an etching effect originating from both ion bombardment, when ions gain velocity across the plasma sheath, and some chemical etching effect of plasma species.

J ie Z heng , R ong Y ang , Lei X ie, J iang lan Qu, Y ang L iu, and X ing g uo Li, Adv. Mater. 2010, 22, 1451–1473

-An external bias is often applied on the substrate to enhance the ion bombardment.

-For nanostructure fabrication by etching, an etching mask has to be present to enable position-selected etching. The etching mask could be produced by lithography as well as self-assembly. The latter provides a facile method for mask generation.

Fabrication of vertically aligned Si nanowires in a mic row ave plas ma reac tor

-A technique involving a combination of using self-assembled nanomask and anisotropic plasma etching is developed for fabricating vertically aligned single-crystalline Si nanowires SiNWs.

J. C. She, S. Z. Deng,a N. S. Xu, R. H. Yao, and J. Chen, APPLIED PHYSICS LETTERS 88, 013112 2006

-The SiNWs are shown to have excellent field emission performance

-The silicon wafer with CH4/H2 plasma for 1 h to generate self-assembled SiC quantum dots on the silicon wafer surface, which served as the etching mask.-Pure H plasma was used for the etching process, during which the SiC quantum dots protected the silicon underneath from the plasma, resulting in the formation of vertically aligned Si nanowires with SiC capping. -The crystalline Si and SiC lattice images were observed in one nanowire, confirming the mask effect of the SiC dots. -It was found that the length of the formed nanowires increases with increasing H2 plasma etching time. In both steps, the substrate temperature and bias were 500 °C and −200 V, respectively.

-The typical scanning electron microscopy SEM images of the nanowires fabricated. The diameter and the length of the nanowires are between 10 and 40 nm and 1–1.2 µm, respectively

J. C. She, S. Z. Deng,a N. S. Xu, R. H. Yao, and J. Chen, APPLIED PHYSICS LETTERS 88, 013112 2006

-TEM study shows that each nanowire has a solid core of single crystalline Si Fig. 1b. Both the sidewall and apex of the nanowire are covered with a thin layer of amorphous film Fig. 1c.

M ethod of g eneration of the etc hing mas k by depos ition of thin meta l layer and heat the s ubs tra te up to the melting point of the meta l.

-The thin metal layer will selfassemble into small liquid droplets dispersed on the substrate surface, which serve as the etching mask.-Etching mask was generated by treating a 20-nm-thick Cu film in NH3 plasma at 700 oC for 2min. Cu/Si alloy nanoparticles were formed and dispersed on the silicon surface, which served as the mask for the subsequent etching -The etching was performed in an NH3/C2H2 plasma with 550–650V substrate bias.-Conically shaped nanostructures with sharp tips were formed, standing perpendicular to the substrate. The sharp tips were found Cu rich.

K. L. Klein, A. V. Melechko, J. D. Fowlkes, P. A. Rack, D. K. Hensley, H. M. Meyer, L. F. Allard, T. E. McKnight, M. L. Simpson, J. Phys. Chem. B 2006, 110, 4766.

K. L. Klein, A. V. Melechko, J. D. Fowlkes, P. A. Rack, D. K. Hensley, H. M. Meyer, L. F. Allard, T. E. McKnight, M. L. Simpson, J. Phys. Chem. B 2006, 110, 4766.

Schematic illustrations of the spontaneously formed etching masks of Cu/Si alloy nanoparticles.

S. Xu, I. Levchenko, S. Y. Huang, K. Ostrikov, Appl. Phys. Lett. 2009, 95, 111505.

Self-organized vertically aligned single-crystal silicon nanostructures with controlled shape and aspect ratio by reactive plasma etching-The formation of vertically aligned single-crystalline silicon nanostructures via “self-organized” maskless etching in Ar+H2 plasmas was obtained. The shape and aspect ratio can be effectively controlled by the reactive plasma composition.

-In the optimum parameter space, single-crystalline pyramid-like nanostructures are produced

-The following two concurrent sets of processes were used:

a) Ar sputtering and hydrogen etching to create vertical CSARnS (controllable shape/aspect ratio NSs) which leads to smooth conical structures with smaller surface areas (the unterminated cones are thermodynamically more stable than pyramids) and

b) terminating their surfaces with hydrogen to stimulate the reshaping of the cones into hydrogen-terminated nanopyramids which would have lower surface energy and would thus be more stable

-The CSARnS arrays were formed in low-frequency inductively coupled plasmas ICPs. Lightly doped Si100 and Si111 wafers were placed on the dc-biased substrate stage positioned in the area of the maximal plasma density in the reactor.

-The total pressure of the gas mixture was maintained at 45 mTorr and the substrate temperature TS range was from 200 to 500 °C. US=−50 to 100 V dc bias was applied to the substrate holder. The rf input power Pd was in the range of 0.8–2.0 kW


-Figure 2 shows the SEM image of Si NSs developed on the Si substrate US=−50 V in the ICP discharge Pd =2.0 kW at high a) and low b) H2 content in the Ar+H2 gas mixture, for tet=30 min. One can see that the singlecrystal nanopyramids arose at the high hydrogen content H2 :Ar ratio µg=3:1; the inset in Fig. 2a shows the nanopyramid shape.

-However, with the low H2 content H2:Ar ratio g=1:3, the vertical NSs were not formed and only close-to-spherical nanodots appeared Fig. 2b.



Complete picture of the Si CSARnS formation in reactive low-temperature H2+Ar plasma environment (Fig. 4)

DBD plasma for surface treatment

Ulrich Kogelschatz and Jurgen Salge High-pressure plasmas: dielectric-barrierand corona discharges – properties and technical applications, ed. by R. Hippler, et al Low Temperature PlasmasFundamentals, Technologies, and Techniques, WILEY-VCH Verlag Berlin GmbH5th June 2007.

-Dielectric-barrier discharges (DBDs) and corona discharges represent self-sustained non-equilibrium electrical gas discharges that can be operated at pressures of the order of 1 bar.

-Dielectric-barrier discharges are characterised by insulating layers on one or both electrodes or on dielectric structures inside the discharge gap.

-Corona discharges depend on inhomogeneous electric fields at least in some parts of the electrode configuration, thus restricting the primary ionisation processes to a small fraction of the interelectrode region.

At atmospheric pressure the physical processes in both types of discharges are similar and resemble those in transient high-pressure glow discharges. Both discharges can be reliably operated up to high power levels in the megawatt range, a property which is of importance for industrial applications.

-The first dielectric-barrier discharge, sometimes also referred to as silent discharge or barrier discharge, was proposed by W. Siemens in 1857.


-Usually DBDs at atmospheric pressure consist of many tiny parallel current filaments referred to as microdischarges.

-Under special conditions also homogeneous discharges can be obtained.

-Most of the applications are operated up to now with filamentary discharges; but homogeneous discharges are coming up and open new perspectives.

Tao Shao et al, Applied Surface Science 256 (2010) 3888–3894

For the treatment, two discharge modes are used, which are referred to as the homogeneous DBD (HDBD) and filamentary DBD (FDBD).

1. Filamentary DBD discharges

Electrode configurations and discharge evolution


The 4 typical stages are shown schematically

-If the electric field in the gas gap is sufficiently high to initiate avalanches, the breakdown starts with the Townsend phase. Next a streamer occurs and a conducting channel – the filament – is formed. Now charges are transferred through the channel and accumulate at the dielectric surface. The voltage across the filament is compensated and the discharge dies out (phase No. 4). The complete discharge development takes only about some 10 -9 s.

Results of discharge modelling.

-When an overvoltage is applied to the discharge gap, an electron avalanche starting at the cathode soon reaches a critical stage where the local eigenfield caused by space charge accumulation at the avalanche head leads to a situation, where extremely fast streamer propagation towards both electrodes is initiated. Streamer propagation is caused by ionisation waves traveling at a speed much higher than the electron drift velocity.

-Such computations come to the conclusion that extremely high electric fields occur at the streamer head, that a slender conductive channel (diameter of the order 100 µm) is formed with maximum electron densities in the range of 10-14 to 10-15 cm-3. Charge accumulation at the dielectric surface leads to a collapse of the electric field at this location and thus chokes the microdischarge typically after a few ns.

-The transported charge and the energy dissipated in a microdischarge can be influenced by several parameters: gas properties and density, thickness and permittivity of the dielectric barrier. Depending on the application microdischarge properties can be tailored to optimise the ensuing plasma chemical reactions.

-Lichtenberg figure are recorded directly on a photographic film together with the experimental arrangement. The emulsion of the film was facing the discharge gap, and a glass plate acted as a dielectric barrier. After applying a single steep rectangular voltage pulse of 15 kV the film was taken out in a dark room and developed.

-Besides numerous footprints of microdischarges gliding discharges fed from the filaments cover the surface. Intensity and extension of footprints and surface discharges differ remarkably.

-Different conditions exist for each microdischarge. One major reason seems to be that in spite of the steep voltage pulse not all the discharges are initiated at the same time. Those ignited first touch the dielectric surface first, and gliding discharges can spread undisturbed over a large area.

-The further development of new discharges is determined mainly by the charges deposited on the dielectric surface by preceding microdischarges together with the applied voltage.


-At t1 an electric field is established. At t2 the microdischarges are established simultaneously, which short-circuit the gas gap; surface discharges described above cover the whole dielectric barrier. The microdischarges extinguish, and the resulting voltage across the gas gap is close to zero. In the gas gap remain channels of the extinguished microdischarges; their conductivity decreases as the recovery continues. These channels represent privileged locations for the ignition of new microdischarges, if the applied voltage is reversed.

-There exist a variety of methods to control barrier discharge. Besides voltage wave form, voltage amplitude, frequency, and capacitive energy stores connected in parallel to the electrodes, the electrode configuration, the design of the dielectric barriers, the kind of gas, the gas flow in the gap determine the microdischarge distribution and their intensity.

- For all applications it is important to obtain a statistically uniform microdischarge distribution in the gas gap and on the surfaces, respectively. The recovery behaviour of the extinguished discharge channels has a dominating influence on this distribution.

-The connection between applied voltage, discharge establishment, memory charges on the dielectric barrier, and reignition.

-The microdischarges develop with differences in time. Figure elucidates the situation for a single voltage pulse. The current through the barrier system indicates two discharge periods. The second period starts before the applied voltage has changed its polarity. current densities of the order of 100 A/cm2 in thin cylindrical filaments of about 100µm radius.

2. Homogeneous DBD discharges

-It has also been demonstrated that dielectrically controlled homogeneous or uniform discharges at atmospheric pressure can be established.

-In principle these discharges allow a completely uniform treatment of gas volumes and surfaces. If reliable control can be provided and if an energy transfer into the discharge is obtained comparable to that of filamentary discharges, this type of discharges seems to be of particular interest in view of industrial applications.

Typical current pulse together with the voltage wave form obtained from a uniform discharge in nitrogen at atmospheric pressure. The electrodes consist of copper foils covered with wire mesh and Mylar foils 350 µm thick. A sinusoidal voltage of 50 Hz was applied. The large current peak of nearly 7 A and the short pulse duration of 15 ns seems to be caused mainly by the dielectric material and by the electric field formed by the wire mesh.

-The barrier is an electret able to accumulate charges on its surface. Supported by the applied voltage charge carriers are trapped more or less uniformly on the surface. If the electric field changes its polarity and a certain threshold is exceeded, the charge carriers are expelled spontaneously from the surface and the development of filaments is prevented.

J. Tepper, M. Lindmayer, J. Salge, Proc. Hakone VI, Int. Symp. on High Pressure, Low Temperature Plasma Chemistry, Cork, Ireland, p. 123–127 (1998)

Surface treatment and modification by atmospheric DBD -The treatment of surfaces by dielectrically controlled barrier discharges is a well-established method to improve surface properties like wettability or adhesion.

-Usually the surface to be treated is moved continuously and exposed to filamentary discharges in air at atmospheric pressure.

-the arrangement for the treatment of conductive and non-conductive foils.


The basic design of an open-air system which allows a treatment of moving foils.

-The storage coils are arranged in open air. The foil is pulled across a metal roll coated with a dielectric barrier. A box which forms small slits with the coated metal roll and the foil contains a number of electrodes and exhaust systems.

-The atmosphere in the box and, in particular, in the discharge areas between the electrodes and the foil is controlled by the gases supplied through the electrodes. The gas mixture is exhausted from the box via a gas absorbing and conditioning unit to the open air.

A typical example for the efficiency of this method is the improvement of the surface tension and its stability of biaxial oriented polypropylene (BOPP) foils. Figure shows that a conventional treatment in air is insufficient. If the foil is first exposed to discharges in argon and then to discharges in acetylene, the surface tension increases to 72 mN/m and remains constant with time.

S. Meiners, J.G.H. Salge, E. Prinz, F. F¨orster, Surface and Coatings Technoloy 98, 1121–1127 (1998)

S E Babayan, J Y Jeong, V J Tu, J Park, G S Selwyn andR F Hicks , Plasma Sources Sci. Technol. 7 (1998) 286–288.

RF cold atmospheric plasma jet for PECVD deposition thin films(SiO2 thin films) and surface treatment.

H. Barankova and L. Bardos , Appl. Phys. Lett., Vol. 76, No. 3, 17 January 2000

Atmospheric fused hollow cathode discharge for surface treatment

RF torch dischargeV. Kapicka, et al., Plasma Sources Sci. Technol. 8 (1999) 15–21.

RF barrier torch discharge with plasma jet

Z Hubicka,, M. Cada, M Sıcha, A Churpita, P Pokorny, L Soukup and L Jastrabık, Plasma Sources Sci. Technol. 11 (2002) 195–202

Barrier torch multi-plasma jet with Al and SiO2 substrate

Multi torchSingle torch

Atmospheric barrier torch discharge with plasma jet

•Working at atmospheric pressure.

•Used for deposition of different kinds of thin films, for example ZnO or TiOx.

•Films are deposited from precursors (Zinc acetylacetonate, Titanium (IV) tetraisopropoxide) carried by working gases (He, N2).

Multi-nozzle system (multitorch)

Vzdělávání výzkumných pracovníků v Regionálním …fyzika.upol.cz/cs/system/files/seminare/2011-01-28...Vzdělávání výzkumných pracovníků v Regionálním centru pokročilých

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