www.forth.gr

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www.forth.gr
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ACTIVITIES of PEML

• Performing the growth of metal oxide thin films
  onto various substrates
• Growth process optimization for particular thin
  film applications
• Structural, Optical, Electrical, Mechanical,
  Chemical characterization
• Material design for passive and active coatings
• Testing and optimization of prototype sensors

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Growth and Characterization

• Metal-oxide film production (InOx, SnOx, ZnOx and
  doped)
• physical vapor deposition systems
• dc reactive magnetron sputtering
• metal evaporator
• Electrical characterization
• DC / AC
• Optical characterization (off and on-line)
• UV/VIS Spectrophotometer (scan range 200-900nm)
• FTIR 50-8000 wave numbers
• Structural characterization
• Thickness measurement
• X-Ray Diffraction
• Electron Microscopy (SEM, TEM)
• Atomic Force Microscopy (AFM)

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DC Reactive Magnetron Sputtering

• Alcatel sputtering two-target system with in-situ
  thickness monitor
• UHV chamber
• target dimensions 150mm diam. ? 6mm thick.

• Variation of deposition parameters ? film
  properties
• Substrate temperature (RT-500ºC)
• Plasma power
• Partial gas pressure (O2, Ar)

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Group Activities
Photoreduction and oxidation of a 60-nm-thick
InOx film deposited at room temperature

• Metal-Oxide Film Production Characterization

• Optical image of a transducer

Interdigitated structures of a SAW device
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Group Activities

• Metal-Oxide Film Production Characterization

• Targets for sputtering
• Zn , In, Sn (pure)
• ZnAl2 (2 Al-doped Zn)
• Metallic ZnIn5 (5 In-doped Zn)
• ZnAl1.5 (1.5 Al-doped Zn)
• ZnSnAl 30/1.2 (30 Sn-doped and 1.2Al-doped
  Zn)
• ZnO (pure)
• ZAO2 (2 Al2?3-doped ZnO)
• ZAO2D (2 Al2?3-doped and 1000ppm Si doped ZnO)
• Ceramic ZAO5 (5 Al2?3-doped ZnO)
• TiO (pure)
• TiONbO (30 Nb2O5-doped TiO)

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Group Activities

• Metal-Oxide Film Production Characterization

• High quality transparent thin films for sensing
  and architectural applications
• Controlled growth
• Controlled oxygen-argon atmosphere
• Sputtering parameters film thickness, substrate
  temperature, total pressure, partial pressures of
  Ar and O2, O2/Ar concentrations, growth rate,
  plasma parameters (current/voltage)
• various substrates

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HIGHLIGHT of RESULTS
The dynamic response of the InOx films towards
nitrogen dioxide at an operating temperature of
200ºC.
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HIGHLIGHT of RESULTS

• High conductivity changes under UV-exposure,
  reductive-oxidative gases.
• Gas Sensor for NO2, NO, O3 in the sub-ppm range
• Low operating temperature applications.
• Sensor for oxidant VOCs

Schematic illustration of the apparatus used for
the photoreduction and oxidation procedures of
InOx films
Typical photoreduction-oxidation conductivity
curve for InOx thin films.
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HIGHLIGHT of RESULTS
Electron Probe Micro Analysis (EPMA)
InO atomic ratio as a function of depth in the
near surface region derived from SIMS-depth
profiles
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HIGHLIGHT of RESULTS
High transparent coatings (e.g. 2Al doped ZnO)
484 RMS0.906 nm
Very smooth surfaces Sub-nanometric RMS
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HIGHLIGHT of RESULTS
Active coatings titania
TiO, 100nm, 0,195nm RMS

• Extremely smooth Surfaces (see Z-Range lt4nm!),
  Roughness below 1nm
• Amorphous
• Film Resistances 1010 O/cm2
• Highly Transparent 85

• TiO and TiONbO films exhibit Hydrophobicity and
  Hydrophilicity under UV Exposure

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IDT Frequency Response
IDT Frequency Response
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HIGHLIGHT of RESULTS SAW devices
Ozone Sensing Properties of InOx
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Projects / Funding
Cardiff Cambridge
Grenoble Paderborn
Lund Dortmund

• HPRN - CT2002 - 00298, 2002-2006 "Photon Mediated
  Phenomena" 110 K
• RTD CEC project No ENK-CT-2002-00678, 2002-2006
  "3 rd Generation Large Area Coatings"   3 rd Gen
  LAC 275K
• Marie Curie,   MRTN-CT-2003-504826, 2003-2007
  "Advanced Methods and Tools for Handling and
  Assemply in Microtechnology" "ASSEMIC" 223K
• Greek Australian (RMIT) 66K
• Greek Romanian (NIM) 25K
• PENED 132K

Fraunhofer IST Braunschweig Heraeus
Applied Films Semco Glastechnik
Glass Coating Velno, NL Uppsala
TU Vienna ARC Seibersdorf GMBH
Oldenburg Nascatec GMBH
Warszawa Pol. IMT Bucharest
Uninova Scuola St Anna
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Group composition

• Ass. Prof. G. Kiriakidis
• Dr. D. Dovinos (SAW design)
• S. Christoulakis (growth/electrical/UV-VIS/XRD)
• K. Moschovis (growth/electrical/SAWs)
• M. Suchea (material design/characterization-
  AFM/SEM/Optical/Contact Angle)
• G. Kenanakis (XRD/electrical/sensing)
• P. Horvath (mechanical properties)
• G. Kortidis (applications)
• V. Tudose (surface chemistry/sensing)

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People