plasma chemistry at department of physical electronics, mu ...€¦ · invited lecture cespc ii,...

Invited lecture CESPC II, Brno 2008 1

Plasma Chemistry at Department of

Physical Electronics, MU Brno

The past - the present - the future

J. Janca


Foundation of Department of Electronics and Vacuum Physics (now Department of

Physical Electronics) at Faculty of Science

Prof. Václav Trunecek: ∗ 1919 - † 1997

1960 - first head of the Department


Industrial plasma technologiesThe ozone production - barrier (silent) discharges, APG ?

Plasma chemical reaction No 1. Nearly 70 different reactions are connected with

creation and anihillation of ozone molecules. 15 reactions are usually taken in account,

only 4 are fundamental.• Biological purification of drinking water

• Chemical industry

• Environmental problems

• Brown-Boveri (Swiss) – Eliasson, Kogelschats

• Tech. University Aachen – Pietsch

• University of Moscow – Filipov, Gibalov, Kozlov

• University of Greifswald – H. E. Wagner, J. Meichssner

• Sofia University. Hiroschima – S. OkazakiPredominant problem – production economya

aupper limit: 100 % ≈ 1.22 kg/kWh, the best experimental laboratory values 0.25 - 0.3 kg/kWh


DPE MU, Brno – entirely new system (combined barrier discharge with plasma electrode

and UV radiation): the ozone generation is not sensitive with respect to air humidity.

180 nm – ozone generation, the ozone absorption 200 – 300 nm

Ozonizer tube (left)a and diagram of the electric circuit (right),

Brno 1987 (patent) - 7 Wh/1 g of ozone from dry oxygenaOzonizer tube: 1 - gas inlet, 2 - cooling water, 3 - hollow elec trode, 4 - gas gap for formating of the silent discharge, 5 -

irradiated layer of cooling water, 6 - inner discharge tube e lectrode, 7 - Teflon plug, 8 - silicone ring, 9 - silica tube, 10 - metal

tube, 11 - gas outlet, 12 - cooling water outlet


Plasma etchingentirely changed the microelectronics technologies (LSI and VLSI integrated circuits,

structures< µm)

• low temperature, low pressure, non-isothermic RF, MW plasma

• barrel and planar plasma reactors

• anisotropic and selective plasma etching

• RIE (reactive ion etching) (bias or self bias on the substrate)

• CF4 + O2, C2F6 + O2, another etching gases

• mask etching, hydrophobic properties

• proximity effects

DPE MU, Brno - cooperation with Tesla Roznov enterprise

• development of end point detectors of plasmachemical etching and ashing


PECVD, PACVD

• plasma enhanced (assisted) chemical vapor deposition

• DC, AC, RF, MW discharges and afterglow is used. Barrel and planar reactors,

plasma jets and torches.

• Applications: microelectronics, thin films, sensors, planar optical waveguides,

integrated optics, metallurgy

• SiOx, Si3N4, FeNx, Al2O3, BN, AlN, TiO2, . . .

DPE MU, Brno (1980) : PACVD barrel deposition system of Si3N4 (final insulation of

microelectronic devices at temperatures < 400 oC, compressive stress). Working gas

mixture – SiH4 + NH3 + N2.


a Experimental apparatus for the deposition by PECVD techniqueadetail image of the reactor


Plasma polymerization• numerous hierarchy of monomers (hydrocarbons, fluorocarbons, siloxanes,

silazanes, . . . )

• Low pressure RF, MW discharges

• plasma afterglow

• high pressure barrier discharges

• Atmospheric Pressure Glow Discharges

• protection thin films, selective permeable thin films, selective adsorbing thin films

• membranes for reverse osmosis

• hydrophilic and hydrophobic thin films

• biocompatible thin films and coatings

• combined techniques (plasma polymerization + magnetron sputtering) UK Prague –

Prof. Biederman

• self-cleaning thin films, non-soiling thin films


DPE MU, Brno :

• Protective thin films (HMDSO) on Al coated head lamps (cooperation with Autopal,

Novy Jicin).

• Antithrombogenic biocompatible thin films on polyester vascular grafts (EU

international project).

• Humidity sensors. Sensors for concentration measurements of anaesthetic gases.

• Optical antireflection and protection coatings (cooperation with Meopta, Prerov).

a Biocompatible thin films on polyester vascular grafts

aworking gas cyclofluorbutane, polymer tetrafluorethylene - teflon


Plasma surface treatment• low pressure RF and MW discharges, DC or AC corona discharges, barrier (silent) or

APG discharges, plasma jets (plasma pencil).

• Hydrophobic and hydrophilic coatings (durability) + grafting.

• Natural materials (wool, cotton, silk, moher) – treatment agains shrinking (stretching),

felting, crumbling. Cl containing gaseous mixtures.

• Polyethylene and polypropylene foils. Non woven fabrics.

• Biocompatible surface treatments and plasma coatings.

• Paper, glass, millipore non-expanding (swell up) materials .

DPE MU, Brno• Surface treatment of non woven polypropylene textile fabrics in APG coplanar

discharges.

• Biocompatible coatings (chitosan).

• Measurement of surface energies by the help of contact angle measurements.

Development of SEE system. More than 40 systems delivered to our customers.


a Surface Energy Evaluation System (See System) and water drop on the uncoated (top)

and on the coated (bottom) filter paper surface in the mixture of HMDSO and N2

a instrument for contact angle measurement and surface free e nergy determination Advex PhotoCat - instrument for eva-

luation of self-cleaning properties of photocathalytic su rfaces based on contact angle measurement


Surface barrier discharge (SBD) and diffuse coplanar surface discharge (DCSD)a

aSBD: e1 - surface electrode, d - glass insulator, e2 - rod elec trodes, s - cellulosic substrate, p - plasma.

DCSD: discharge electrode system and cross sectional distr ibution of DCSD normalized light emission at atmospheric pr es-

sure, nitrogen, gap voltage 8 kV, 6 kHz.

Šimor M., Ráhel J., Brablec A., Slaví cek P., Cernák M., Applied Physics Letters, 2002, p.2716


Mechanical properties are measured by the depth sensing indentation (Fischerscope

H100 with Vickers pyramid: load range 0.4 - 1000 mN, depth sensitivity ± 1nm, max.

depth 0.7 nm)a

aDepth sensing indentation test: Load - penetration curves o btained on several different hard films and boronsilicate gl ass

(BK7) substrate.

V. Buršíková, P. Sládek, P. St’ahel, J. Buršík, J. Non-Crystalline Solids, 352, 9-20, od p. 1238-1241, 4, 2006.

V. Buršíková, P. Sládek, P. St’ahel, J. Buršík, J. Non-Crystalline Solids, Nizozemsko : Elsevier Science B. V., 352, 9-20, p. 1242-

1245, 4, 2006.


Light Sources Based on DBD Discharges and Excimer MixturesDPE MU, Brno a

• to study the of UV excimer radiation generated in different DBD discharges

• to find optimal configuration as efficiency and intensity of emitted light in UV range

• to use DBD discharges (particularly diffuse coplanar surface discharge - DCSD) for

excitation for excitation of green, red and white phosphors

• working mixtures Xe/Cl2 or Kr/Xe/Cl2, Xe/I2 or Ne(Kr)/Xe/I2

• total pressure 0.05 and 1 bar, 1-100 kPa for excimer radiation at 253 nm (XeI*), .

• power supply sinusoidal pulses with peak-to-peak voltage up to 27 kV, frequency

range 1 - 10 kHz, typical excitation frequency: 8 - 9 kHz

development of mercury-free fluorescent lamps

aBrablec A., Jan ca J., St’ahel P., Slaví cek P., Guivan N., Shimon L., J. Phys. D: Appl. Phys., 38 (2005 ) p. 3188.


Sliding DBD with sinusoidal pulses and cylindrical excimer UV lampa

aSliding DBD - Kr/Xe/Cl 2 = 92/8/1 mbar, interelectrode gap: 3 cm, f = 8 kHz, input power : 15 W. Cylindrical excimer UV

lamp: : length - 150 mm, outer quartz tube diameter - 30 mm, gap - 5 mm, obligatory cooled by air.


Hard and supra-hard materials• Low pressure RF, MW and low temperature plasma.

• Low pressure MW but high temperature plasma.

• Plasma torches. Combined techniques with ion beam bombardment.

• DLC : 70th years - Prof. Holland, Oiha, University of Bristol

TU Munich (Prof. Veprek), TU Wien (Dr. Störi), Lodz (Prof. Mitura), Moscow (Prof.

Deruyagin, Prof. Fedoseev), Kijev (Dr. Schulzenko), Bachmann & Weismantell

(Germany).

DPE MU, Brno

• Microcrystalline diamond coatings.

• DLC, a-C:H, DLC/SiOx thin filmsa .

• Composites (diamond + amorphous matrix)

• TiN, AlN, cubic BN coatings.

aV. Buršíková, L. Zají cková, P. Dvo rák, M. Valtr, J. Buršík, O. Bláhová, V. Pe rina, J. Jan ca. Journal of advanced oxidation

technologies, 9, 2, p. 232-237, 5, 2006.


PECVD of SiOxCyHz thin filmsa, transparent multifunctional gradient coatings on

polycarbonates; PECVD system for complex diagnostics of capacitively coupled r.f. glow

dischargeaL. Zají cková, V. Buršíková, D. Franta, A. Bousquet, A. Granier, A. G oullet, J. Buršík. Plasma Processes and Polymers,

Weinheim : Wiley-VCH, 4, S1, p. S287-S293, 2007.

L. Zají cková,V. Buršíková, Z. Ku cerová, D. Franta, P. Dvo rák, R. Šmíd, V. Pe rina, A. Macková. Plasma Sources Science and

Technology , 16, 1, p. S123-S132, 10, 2007.


Different allotropic carbon formsFullerenes, nano-tubes (double wall or single wall) graphene layers ( low effective

electron mass, Fermi velocity 1/300 of light velocity).

Production for plasmachemical micromechanical cleavage method - 1000 USD/piece of

graphene with linear dimension as human hair

Graphene and all the "graphitic" materials: graphene (plane carbon atoms - top),

graphite (bottom, left), carbon nanotube (bottom, center), buckyball (bottom, right)a

aA. K. Geim and P. Kim, Scientific American, April 2008, p. 68


DPE MU, Brno

Fullerenes


Deposition of carbon nano-tubes in MW plasma torch and typical resultsa

aMixture of CH 4/H2/Ar at atmospheric pressure, MW 2.45 GHz with max. power 2 kW, line to iron two channel nozzle

electrode. mw power 400 W, flow rates Ar 1500 sccm, H 2 100 - 400 sccm, CH 4 flow rate 10 to 40 sccm, substrate types

Si/SiO2 /Fe, Si/Fe, Si/SiO 2 /Ni, Si/Ni substrate temperature Ts = 550 - 850 oC, no external heating substrate temperature was

measured by the pyrometer with disappearing filament or Rayt ek Thermalert TX pyrometer in the range 500 - 2000 oC,

substrate - nozzle distance 10 to 60 mm, deposition time - 30 s econds to 25 minutes

O. Jašek et al, Carbon nanotubes synthesis in microwave plas ma torch at atmospheric pressure, Materials Science and

Engineering C 26 (2006) 1189 - 1193


Plasma metallurgy• High temperature at atmospheric pressure – very pure metals

• Low temperature, low pressure RF plasma

• simultaneous production of WC during plasmachemical reactions in CH4+H2+Ar

DPE MU, Brno : Reduction of amoniumparatungstate in hydrogen plasma on tungsten

pulver. Advantages – increased surface activity, better sintering properties, increased

catalytic activity.

Plasma metallurgy


Environmental plasma chemical technologies

• Corona discharges, DC and AC glow discharges, gliding arc, plasmatrons, RF and

MW torch discharges, plasma jets, pulse discharges in liquid media.

• Disintegration (decomposition) of different industrial pollutants and communal wastes.

• Main problems: Economy and possible generation of another dangerous pollutants

(dioxines). Prof. Czernichowski, GREMI Orleans (gliding arc – SH2) in CZ - IPP CAS,

Prague (pulse discharge in polluted water - Sunka, Lukes), FEL CVUT, Prague

(corona discharges – Pekarek), KU Bratislava (corona discharges, Morvova), Poland

(Mizeraczyk, Opalinska, Dors)

DPE MU, Brno

• RF unipolar torch discharges

• Multi-step gliding discharge.


Experimental devices for environmental plasma application:


Restoration and conservation of archeological and histori calartifacts

a

aSilver coins cemented together by the corrosion (right, top ) and after the reduction of the corroded material (right, bo ttom)

in the plasma reactor (left)


Cutting and treatment of biological tissue by plasma pencil (left) and the temperature

map by IR cameraa

a13.56 MHz generator, RF atmospheric pressure plasma pencil , working gas Ar, inner diameter of dielectric nozzle 0.4 mm


Experimental determination of rate constants of selected p lasmachemical reactions by ESR

• Non-invasive measurements of N, O densities in MW plasma afterglow

• Electron density determination by ECR during ESR measurements

• Separation of N14 and N15 in early afterglow

• Determination of rate constants for following plasma chemical reactions: OMTS + O ;

HMDSO + O, HMDSZ + N

• Deposition of AlN and polymeric thin films in nitrogen MW (2,4 GHz) afterglow


DPE MU, Brno

3.7 10-4 T 3.7 10-4 T

1864px 1864px 3P13P1

3P2

ESR apparatus with characteristic spectra of nitrogen (left) and oxygen (right)a

aESR device: JEOL - JES - 3B with maximal value of magnetic field - 0.9 T

plasma chemistry at department of physical electronics, mu ...€¦ · invited lecture cespc ii,...

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