Pulse low temperature plasma systems for the deposition of oxide - - PowerPoint PPT Presentation

Summer school PPST, Koszalin, August, 20, 2008 Poland

Pulse low temperature plasma systems for the deposition of oxide thin films

• Z. Hubička1, M. Čada1, P. Virostko1,2 , V. Straňák1, Š. Kment1, J.

Olejníček1, P. Adámek1, L. Jastrabík1, M. Tichý2, P. Jelínek1, I. Gregora1, P. Kudrna2, M. Čičina1, R. Hippler3, P. Klusoň4, J. Krýsa4

1 Institute of Physics, Academy of Sciences of the Czech

Republic,v.v.i., Na Slovance 2, 182 21 Prague 8

2 Charles University in Prague, Faculty of Mathematics and Physics,

V Holešovičkách 2, 180 00 Prague 8, Czech Republic

3Ernst Moritz Arndt Univ Greifswald, Inst Phys, D-17489 Greifswald,

Germany

4Institute of Chemical Technology, Technicka 5, 166 28 Prague 6,

Czech Republic

Summer school PPST, Koszalin, August, 20, 2008 Poland

Acknowledgments

• Ministry of Education, Youth and Sports,

Research plan MSM 0021620834

• Czech Science Foundation,

grant 202/06/0776

• Grant Agency of the Academy of

Sciences of the Czech Republic, grant KAN 101120701, KJB100100707 and KJB100100805

Summer school PPST, Koszalin, August, 20, 2008 Poland

LECTURE OUTLINE

• 1. Motivation of the research aiming at deposition of TiO2.
• 2. Low-pressure plasma sources used for deposition of TiO2.

a) UHV single plasma-jet system. b) UHV double plasma-jet system. c) Surfatron plasma jet system. d) DC planar magnetron.

• 3. Atmospheric pressure plasma source – barrier torch discharge.
• 4. Samples of plasma diagnostics.
• 5. Measurements of the ion current flowing at the substrate.
• 6. Measurements of power deposited at the substrate by using

thermocouple probe.

• 7. Conclusion and future prospects.

Summer school PPST, Koszalin, August, 20, 2008 Poland

Motivation

• The aim - preparation of hiearchical multicomponent structure (sensors, solar cells)
• Low temperature deposition is sought
• The information of photo-electrochemical properties of TiO2 is one of the most important

2 Thin film of M-phtalocyanine

Sensitivization of TiO2 Deposition – CVD

Layer of photoactiveTiO2

Photoactive layer

Layer of ZnO - TCO layer

(Transparent Conducting Oxide) Filter of UV radiation Protective layer

Monolayer of Au Enhance of electron transport

EXPECTED DESIGN OF MULTILAYERS STRUCTURES

Nanoporous alumina - template

Summer school PPST, Koszalin, August, 20, 2008 Poland

Motivation

R.Asahi et al., Science 293 (2001) 269

Oxidation Reduction

O2 O2

• H2O

OH

visible light

cb vb

e- h+

N2p↔O2p

TiO2-xNx particle

Recently, the modification of TiO2 to render its sensitivity to visible-light became one of the most important goals to increase the utility of TiO2. Some approaches:

a) Transition metals doping (Fe, Ni, Zr) X thermal instability X increase of recombination centers b) Reduced form of TiO2 X low electron mobility in the bulk c) Dye sensitization X low efficiency d) Composite semiconductors X fast recombination 2.5 eV The substitutional anionic doping of N→ O By mixing N2p states with O2p states the band- gap of the TiO2-xNx film is reduced <2.5 eV TiO2-xNx films have a visible-light wavelength response 3

Summer school PPST, Koszalin, August, 20, 2008 Poland

Low temperature plasma sources

Barrier torch DC pulsed HC plasma jet RF HC pulsed dual plasma jet Multi-barrier torch MW surfatron DC pulsed planar magnetron

Summer school PPST, Koszalin, August, 20, 2008 Poland

RF, RF modulated, DC and DC pulse plasma jet

Summer school PPST, Koszalin, August, 20, 2008 Poland

Hollow cathode effect

Summer school PPST, Koszalin, August, 20, 2008 Poland

In the case of DC hollow cathode discharge, the pressure region for the optimum development of hollow cathode effect is done by the relation: This relation is valid for cylindrical hollow cathodes with the internal diameter a. This relation says that the mean free path

• f electrons inside the cathode has to be optimal relatively to

the diameter a for the effective development of fast oscillating electrons.

m Pa a p m Pa ⋅ ⋅ ≤ ⋅ ≤ ⋅ 50 1

Summer school PPST, Koszalin, August, 20, 2008 Poland

System with cylindrical hollow cathode

Summer school PPST, Koszalin, August, 20, 2008 Poland

RF hollow cathode effect C1 and C2 electrode can be covered by dielectric material

Summer school PPST, Koszalin, August, 20, 2008 Poland

The RF hollow cathode plasma jet was used for PECVD of a- Si:H and for PVD of many types of thin films:

• TiN deposition by sputtering of a Ti nozzle
• stoichiometric Ge3N4 thin films
• CNx thin films
• Cu3N thin films
• Pb(ZrxTi1-x)O3 ferroelectric thin films
• BaxSr1-xTiO3 ferroelectric thin films

DC and DC pulsed plasma jet with hollow cathode was used for:

• TiO2 thin films
• ZnO thin films
• Si:H, SiGe:H, GeC semiconductor thin films deposition
• SiC semiconductor thin films

Summer school PPST, Koszalin, August, 20, 2008 Poland

Dependence of pressure at the hollow cathode outlet on mass flow rate through the cathode with internal diameter 5 mm

Summer school PPST, Koszalin, August, 20, 2008 Poland

DC pulse hollow cathode plasma jet RF modulated hollow cathode plasma jet

? =

• RF, modulated RF hollow cathode plasma jet (Ti hollow

cathode)

• DC and DC pulse hollow cathode plasma jet (Ti hollow

cathode)

Summer school PPST, Koszalin, August, 20, 2008 Poland

Double DC Pulsed Hollow Cathode Plasma Jet System for deposition

• f TiO2 and TiO2:N thin films

5

• Hollow cathode: titanium nozzle

inner diameter d = 5 mm and length l = 30 mm.

• Working gases [sccm]: Ar (80), O2 (100)
• Total pressure: in the range 2-5 Pa
• pulsing frequency 2.5 kHz with 25% duty cycle
• Distance: nozzle outlet to substrate -30 mm
• Substrate : quartz, ITO (Indium-Tin Oxide)

PRF ≈3 W

Summer school PPST, Koszalin, August, 20, 2008 Poland magnet poles substrates plasma jets

Inside of the Reactor with Double pulsed DC plasma jet

In order to achieve a high thickness homogenity a mask was situated between the supports, which were positioned on a movable bench, and hollow cathodes. Grounded poles of static electromagnet were situated close to the nozzle outlet in

• rder to provide a higher intensity and superior stability of the plasma stream in the

reactor. 6

Summer school PPST, Koszalin, August, 20, 2008 Poland

DC Hollow Cathode Dual Plasma Jet system

substrate turning cooled jet I cooled jet II

Summer school PPST, Koszalin, August, 20, 2008 Poland

Inside of the reactor with double pulsed DC plasma jet during TiO2 and TiO2:N thin films deposition

Summer school PPST, Koszalin, August, 20, 2008 Poland

20 30 40 50 60 70 80 0.0 8.0x10

2

1.6x10

3

2.4x10

3

3.2x10

3

4.0x10

3

Anatase

(B) (A)

Intensity [a.u.] 2Θ [

• ]

(C)

Only the anatase crystal structures were detected by XRD The presence of nitrogen in the plasma influenced the grain size which was estimated from the Scherrer equation and was in the range of 42 nm (A) – 58 nm (C)

XRD – Paralel Beam Geometry ω= 1°

8

480 nm

(A) (B) (C)

XRD analysis of TiO2 and TiO2:N films deposited by double pulsed DC plasma jet

surfatron* - based on principle of microwave resonator

working at frequency 2.45 GHz discharge burns in quartz tube inserted into resonator cavity

* M. Moisan, J. Pelletier, Microwave excited plasmas, Elsevier, Amsterdam (1999).

• A. Ricard, Reactive Plasmas, Societe Francaise du Vide, Paris (1996).

Surfatron based plasma discharge

• V. Straňák, DIAGNOSTICS OF LOW-TEMPERATURE PLASMA FOR

TECHNOLOGICAL APPLICATIONS, Doctoral Thesis, PRAGUE, JANUARY 2007

• surfatron body
• stainless steel vacuum vessel
• plastic flanges
• quartz windows
• VAT butterfly valve
• MKS baratron
• surfatron body
• double-surface quartz tube
• stepper motor operated feed-throughs
• movable table in 3 dimensions
• probe holder
• plasma exiting the tube

Experimental setup - surfatron

Summer school PPST, Koszalin, August, 20, 2008 Poland

Surfatron plasma jet TiO2 deposition

10 mm

21 W, 110 Pa

10 mm

21 W, 500 Pa

10 mm

21 W, 800 Pa

10 mm

21 W, 1100 Pa

10 mm

21 W, 1500 Pa SURFATRON - Sairem GMP03 KE/D (0-300W)

• Chem. precursor: Titan (IV) tetraisopropoxide

Working gases: Ar,O2 (500 sccm/2 sccm) Overall pressure : 1kPa Substrates: quartz discs, ITO glasses Temperature of the substrate : 330 °C Substrate - nozzle distance : 8 mm Time of deposition : 10 – 60 min 7

• V. Straňák, DIAGNOSTICS OF LOW-TEMPERATURE PLASMA FOR

TECHNOLOGICAL APPLICATIONS, Doctoral Thesis, PRAGUE, JANUARY 2007

• effective deposition of thin TiOx films
• low-frequency pulsed discharge* – f = 250 Hz (tactive = 150 μs, tOFF = 3.850 μs)
• discharge properties in peak: Ipeak ≈ 50 A (Ppeak ≈ 25 kW, ipeak ≈ 1 Acm-2)
• average values of discharge: Iav ≈ 600 mA, Pav ≈ 400 W (continual dc source AE MDX)

DC pulsed magnetron deposition of TiOx thin films

• V. Straňák, Marion Quaas, H. Wulf, Z. Hubička, S. Wrehde, M. Tichý, R. Hippler,

Formation of TiOx films produced by high-power pulsed magnetron deposition, Journal of Physics D, (2008) Volume: 41 Issue: 5 Article Number: 055202

N N N S

Magnetron setup for TiOx deposition

• planar magnetron Gencoa, Ti target – diameter 77 mm, working in unbalanced

mode

• TiOx → Ti (target), O2 (reactive gas), Ar (buffer gas)
• main aim : deposition of TiO2 at different pressures and ratios of gas mixture
• diagnostics – time-resolved optical emission spectroscopy

2 4 6 8 10 12 14 16 0,1 1 10

a a A a R T A R+A R+A a R+A T R+A T a a a A A A A T R R T R O2/Ar pressure [Pa]

Structures dependences α-Ti

amorphous

rutile anatase rutile + anatase

Summer school PPST, Koszalin, August, 20, 2008 Poland

Multi torch Single 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).

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

Summer school PPST, Koszalin, August, 20, 2008 Poland

TiO2 deposition by atmospheric pressure plasma jet

Summer school PPST, Koszalin, August, 20, 2008 Poland

20 30 40 50 60 70 80 10 20 30 40

TiO2-Anatase

Intensity [a.u.] 2Θ [

• ]

30 40 50 60 70 80 100 200 300 400 500 600 700 002 004 103 Wurtzit

Intensity [a.u.] 2Θ [

• ]

Properties of films deposited by the barrier torch discharge TiO2 ZnO

Summer school PPST, Koszalin, August, 20, 2008 Poland

1- Irradiation source – LOT LSH201 Hg(Xe) 2- Liquid filter (0.1M CuSO4) 3- Monochromatic filter (365, 404 nm) 4- Mechanical shutter 5- Electrochemical cell

1 2 3 4 5

500 W Hg(Xe) polychromatic lamp Monochomatic filter:

• max. wavelength 365 nm

Photoelectrochemistry – The Experimental Set-up

14

Analysis and comparison of anatase TiO2 thin films deposited by presented plasma systems

Summer school PPST, Koszalin, August, 20, 2008 Poland

Three electrode arrangement:

a) TiO2/ITO glass - working

electrode b) Platinum mesh acting as counter electrode c) Ag/AgCl in 3M KCl - reference electrode (potential of 216 mV vs. NHE – normal hydrogen electrode) d) Electrolyte - 0.1 M Na2SO4

Electrochemical Cell

15

IPCE – Incident Photon to Current Efficiency, i-photocurrent density, F- Faraday constant

A f h

N c h P J ⋅ ⋅ ⋅ = λ

ν

Jhυ – intensity of the photon flux Pf - irradiation intensity, λ - wavelength of used illumination source

.

h

i IPCE F J ν =

Data analysis

Summer school PPST, Koszalin, August, 20, 2008 Poland

IPCE – the influence on the layers thickness

IPCE – Incident Photon to Current Efficiency i-photocurrent density, F- Faraday constant Jhυ – intensity of the photon flux Pf - irradiation intensity, λ - wavelength of the used illumination source

400 800 1200 1600 2000 2400 0.00 0.04 0.08 0.12 0.16

IPCE @ 1V layer thickness (nm)

λ = 365 nm

L1 L2 L3 L4

400 800 1200 1600 2000 0.0 1.0x10

• 3

2.0x10

• 3

3.0x10

• 3

4.0x10

• 3

5.0x10

• 3

6.0x10

• 3

IPCE @ 1V Layer Thickness (nm)

λ = 404 nm

L1 L2 L3 L4

18

The layer Absorption edge [nm] Band gap energy [eV] Sol- gel (L1) 335 3.7 Magnetron (L2) 370 3.4 Hollow cathode (L3) 380 3.3 MW Surfatron (L4) 367 3.4

Summer school PPST, Koszalin, August, 20, 2008 Poland

Plasma jet diagnostics

• cylindrical Pt probe
• d = 200 μm, l = 2 mm
• position: h = 38 mm from the nozzle outlet

(position of substrate)

• reference electrode: grounded reactor

wall

• RF compensation: LC filters tuned at

13.56 and 27.12 MHz and cylindrical compensation electrode

• placed perpendicular to the magnetic field

lines; magnetic field also smaller at the position of the probe ⇒ magnetic field effect neglected

• cleaned from deposited films by ion

bombardment in between measurements

• triggered for pulsed excitation modes

Summer school PPST, Koszalin, August, 20, 2008 Poland

Summer school PPST, Koszalin, August, 20, 2008 Poland

Current density j in the nozzle and instant power PD absorbed in the plasma for continuous DC and pulsed DC excitation modes

• used only Ar gas; pAr =6 Pa
• TA- active part of duty cycle TA=750 ms; TP- pause TP=3 ms; duty cycle ≈20%
• Instant current density j in the nozzle and instant power PD absorbed in the

plasma are higher for pulsed DC excitation mode ⇒higher instant density of charged particles is expected in pulsed DC excitation mode

Summer school PPST, Koszalin, August, 20, 2008 Poland

Dependence of electron temperature in DC plasma jet system

• n DC discharge current; (used only Ar gas Q = 120 sccm; p=2.7 Pa)

Electron temperature in the DC hollow cathode discharge measured in the plasma jet by the Langmuir probe and determined from the slope of electron probe current in semi-logarithmic scale.

Summer school PPST, Koszalin, August, 20, 2008 Poland

Effective electron temperature in the RF hollow cathode discharge calculated from the integral of the second derivative of the Langmuir probe characteristics (mean electron energy). (p = 6 Pa)

Summer school PPST, Koszalin, August, 20, 2008 Poland

DC pulse hollow cathode plasma jet

• p = 3,5 Pa,
• Ar, QAr = 110 sccm,
• TA = 270 μs, TM = 1270 μs,
• ID = 5 A,
• h = 20 mm

Summer school PPST, Koszalin, August, 20, 2008 Poland

DC pulse HC plasma jet – parameters along plasma jet

• p = 3,5 Pa,
• Ar, QAr = 110 sccm,
• TA = 270 μs, TM = 1270 μs,
• ID = 5 A,

h- distance between nozzle outlet and Langmuir probe tip

• h = 20 mm, h = 40 mm

Summer school PPST, Koszalin, August, 20, 2008 Poland

Evolution of the plasma jet parameters during TiO2 deposition by DC pulsed plasma jet (measured at the substrate position)

Ar gas flows through the Ti hollow cathode and O2 enters directly into the reactor average discharge current IDC= 500 mA

Summer school PPST, Koszalin, August, 20, 2008 Poland

Ion current at the substrate during deposition

• during deposition fall at the substrate: sputtered particles,

electrons, positive ions; they can be accelerated by substrate negative potential

• substrate ion bombardment is applied during thin-film plasma-

aided deposition to influence the properties of deposited layers – accelerated ions transfer energy to the created film

• consequently, apart from the plasma parameters it is useful to

know the positive ion current to the substrate

Summer school PPST, Koszalin, August, 20, 2008 Poland

Measurement of the substrate ion current using DC bias

• DC power supply is connected to the substrate
• when the substrate is sufficiently negative, only positive ions fall

at the substrate

• Disadvantage: applicable only for deposition of conductive thin

films; non-conducting layer gets gradually charged up and that shields the accelerating electric field

Summer school PPST, Koszalin, August, 20, 2008 Poland

Deposition of oxide layers

• xide layers, e.g. TiOx, PbZrxTi1-xO3, BaxSr1-xTiO3 (BSTO) are non-

conducting => method using DC bias is not applicable => need for method measuring the ion current during such deposition

• at the disposal there are methods using (i) pulsed DC voltage,

(ii) continuous RF voltage and (iii) modulated RF voltage

Summer school PPST, Koszalin, August, 20, 2008 Poland

Measurement of the substrate ion current using pulsed DC bias (TiO2 deposition)

R U U I

1 2 −

=

• the negative DC bias is periodically interrupted – pulsed DC power supply
• when the substrate is at zero potential the positive charge on the non-

conducting layer gets discharged by electron current

• repetition frequency 30-80 kHz; ω < ωi (repetition frequency vs. plasma ion

frequency)

• applicable for thin non-conducting layers of the thickness ~ 500 nm

Summer school PPST, Koszalin, August, 20, 2008 Poland

Measurement of the substrate ion current using applied RF voltage

• RF frequency 13.56 MHz; ω ≥ ωi
• RF current to the substrate Is(t)=Ii(t)+Ie(t)+Id(t)
• assuming ω >> ωi => Ii(t) is constant = -Ii0
• Sobolewski: when URF reaches its minimum => Ie(t)≅Id(t)≅0 => sampling

the current at that time yields Ii0 (electron current is almost zero since URF is large and negative)

• RF current is measured using Rogowski coil and RF voltage using the

capacitive probe

Sobolewski, M. A., Appl. Phys. Lett., 72(1998)1146,

• Phys. Rev.E, 62(2000)8540, J. Appl. Phys., 90(2001)2660.

Real current and voltage waveforms measured for 1 MHz substrate bias.

( )

S i

t I I =

Summer school PPST, Koszalin, August, 20, 2008 Poland

Measurement of the substrate ion current using square-wave-modulated RF voltage

C I dt dU

i S =

• RF voltage is interrupted – negative DC bias is being discharged by the current of

positive ions in the idle part of the period

• ion current is determined from the slope of the bias decay line
• resistor R serves for discharging the capacitor in the matching unit

Method is analogous to the „ion flux probe“ published by N.S. Braithwaite, J.P. Booth , G. Cunge in Plasma Sources Sci. Technol. 5 (1996) 677-684.

Summer school PPST, Koszalin, August, 20, 2008 Poland

Dependence of the substrate ion current on the DC discharge current

• ion current rises with the discharge current – corresponds to the rise of the charged

particles density – verified by Langmuir probe measurements

• higher ion current from the modulated RF bias method – probably due to

supplemental electron heating by applied RF bias in the active part of the period

• ion current rises with the magnitude of the DC bias – substrate does not present

ideal (infinite) planar probe - influence of the edge effects

Substrate ion current – DC hollow cathode plasma jet

TiO2 deposition Dependence of the substrate ion current on the DC bias at ID=600mA

Summer school PPST, Koszalin, August, 20, 2008 Poland

Substrate ion current – RF hollow cathode plasma jet

• ion current rises with the RF power absorbed in plasma – rise of the

charged particles density – verified by Langmuir probe measurements

• ion current rises with the magnitude of negative DC bias
• at similar power deposited in the plasma is the substrate ion curent

greater in the RF discharge than in the DC discharge (influence of electron heating?) Dependence of the substrate ion current on the RF power Dependence of the substrate ion current

• n the pulsed DC bias at PRF=200W

TiO2 deposition

Summer school PPST, Koszalin, August, 20, 2008 Poland

Continuous RF bias – substrate current and voltage (1)

Problems:

• RF current and voltage can not be measured directly at the substrate => the

measurements are influenced by parasitic capacitances and inductances

• the parasitic current IP (~ 100 mA) is as a rule greater than the substrate ion

current IS (~ 1 – 50 mA)

• we attempted to construct compensation circuit; if the imaginary part of the

compensation circuit impedance at 13.56 MHz has the same magnitude but

• pposite sign as that of the parasitic impedance then (hopefully most of) the

parasitic current would flow via the compensation circuit

• compensation circuit is adjusted for minimum measured current without plasma

Summer school PPST, Koszalin, August, 20, 2008 Poland

• parasitic CP and LP can be estimated from the impedance measured without

discharge and without compensation at the first and second harmonic of the power frequency (ω1=13.56 MHz, ω2=27.12 MHz)

• (n=1,2)
• using CP, LP and the known values of the equivalent circuit CS, LS it is possible to

calculate the substrate RF voltage and current USn, ISn from the values measured

• ff the substrate Un, In ; separately for individual harmonic components ωn (n=1,2)

P n P n n n n

C j L j I U Z ω ω 1 + = =

( )

n P n Ln P P n Sn

V C j I C L I ω ω − − =

2

1

Ln P n n Sn

I L j U U ω − =

S S n n S n n Ln

C L U C j I I

2

1 ω ω − − =

Continuous RF bias – substrate current and voltage (2)

where

measured voltage and current substrate voltage and current (ID = 600 mA, US,DC = -100 V)

Summer school PPST, Koszalin, August, 20, 2008 Poland

Experimental set up for ion flux measurement at different frequencies in hollow cathode plasma jet system

13.56 MHz

pulsed DC pulsed DC

13.56 MHz

Summer school PPST, Koszalin, August, 20, 2008 Poland

Ion flux – for different substrate bias frequencies and different discharge excitation modes

Ion flux determined for different bias frequencies f; substrate bias UDC,S = –50 V. a) DC – in DC discharge, ID = 600 mA; b) RF – in RF discharge with different discharge power PRF. It is known that T

e

depends on the frequency. Higher frequency induces higher T

e and hence also

the ion flux will be higher. The Bohm criterion says that the positive ions get accelerated in the presheath approximately up to the electron temperature. The ion flux is then proportional to T

e 1/2,

ji ∼ T

e 1/2 .

Summer school PPST, Koszalin, August, 20, 2008 Poland

Peak ion flux for PULSED DC hollow cathode plasma jet ; substrate bias UDC,S = –50 V; discharge repetition frequency f = 2.5 kHz, different duty cycle (100% = DC discharge). Average discharge current IDC= 500 mA.

Ion flux – in pulsed DC hollow cathode discharge (different bias frequency, UDC,S = –50 V)

Summer school PPST, Koszalin, August, 20, 2008 Poland

Ion flux – in pulsed DC hollow cathode discharge (50 kHz bias frequency, UDC,S = –50 V)

Average ion flux for PULSED DC plasma jet; average discharge current ID = 500 mA (PD = 100 W); discharge repetition frequency f = 2.5 kHz, different duty cycle. Ar gas flows through the Ti hollow cathode and O2 enters the reactor directly Average ion flux for PULSED DC plasma jet; average discharge current ID = 500 mA (PD = 100 W); duty cycle 10% and 50%, different discharge repetition frequencies.

Summer school PPST, Koszalin, August, 20, 2008 Poland

Time evolution of ion flux for PULSED DC plasma jet; average discharge current ID = 500 mA (PD = 100 W); discharge repetition frequency f = 2.5 kHz, different duty cycle. Ar gas flows through the Ti hollow cathode and O2 enters directly into the reactor

Summer school PPST, Koszalin, August, 20, 2008 Poland

Calorimeter probe applied in DC pulsed magnetron plasma: M. Čada, J.W. Bradley, G.C.B. Clarke, P.J. Kelly, J. Appl. Phys. 102 (2007) 063301.

The thermal power density measurement at the floating substrate in DC pulsed plasma jet

Summer school PPST, Koszalin, August, 20, 2008 Poland

Thermal power density at the floating probe measured for different pulsing frequencies in mixture of argon and oxygen and for two selected duty cycles. Pulsed DC discharge with mean current 0.5 A.

Summer school PPST, Koszalin, August, 20, 2008 Poland

Conclusion Thank you for your attention

• Different low temperature plasmatic methods of TiO2 thin film

deposition were presented.

• Plasma parameters at different conditions of DC, DC pulsed,

RF and RF modulated plasma jet were measured during the deposition of TiO2 thin films.

• Ion fluxes and thermal energy fluxes on the substrate were

compared for different modes of plasma jet excitation.