Advanced search
1 file | 717.41 KB

Capacitance spectroscopy of alumina sol-gel capacitors with Al top contacts

Author
Organization
Abstract
We measured the complex capacitance C(f) of ITO/sol-gel alumina/Al capacitors deposited on glass (and some on stainless steel foil) in the frequency range 15 Hz-10 MHz. The sol-gel films were deposited by dip-coating and following a two-step process. The capacitance C(f) found was much higher than that of a pure Al2O3-film due to the remaining porosity of the film and the uptake of H2O from the environment. The C(f) curves are useful as a sensitive probe for the porosity of the sol-gel film. In particular the evolution of the capacitance curve with time after drying has been measured. The curves can qualitatively be understood by modelling the capacitor as a (nearly) percolating random insulator/conductor network, using the effective medium approximation. However a detailed understanding of the relation between the C(f,t) curves and the structure of the films requires a more elaborate model. Films sintered at 500-550 degrees C for 1 h initially behave exactly as not sintered films but in contrast with the latter they improve slowly over time. Fast sintering yields better films.
Keywords
thin film, sol-gel, capacitance, effective medium approximation, percolation, porosity, AL2O3 HUMIDITY SENSOR, CERAMIC SENSORS, IMPEDANCE, PERCOLATION, FILMS, SIMULATION, ELECTRODES, CONDUCTORS, DEPENDENCE, RESISTANCE

Downloads

  • (...).pdf
    • full text
    • |
    • UGent only
    • |
    • PDF
    • |
    • 717.41 KB

Citation

Please use this url to cite or link to this publication:

Chicago
De Visschere, Patrick, and Karel Vanbesien. 2008. “Capacitance Spectroscopy of Alumina Sol-gel Capacitors with Al Top Contacts.” Journal of Sol-gel Science and Technology 45 (3): 225–235.
APA
De Visschere, Patrick, & Vanbesien, K. (2008). Capacitance spectroscopy of alumina sol-gel capacitors with Al top contacts. JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY, 45(3), 225–235.
Vancouver
1.
De Visschere P, Vanbesien K. Capacitance spectroscopy of alumina sol-gel capacitors with Al top contacts. JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY. Dordrecht, The Netherlands: Springer; 2008;45(3):225–35.
MLA
De Visschere, Patrick, and Karel Vanbesien. “Capacitance Spectroscopy of Alumina Sol-gel Capacitors with Al Top Contacts.” JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY 45.3 (2008): 225–235. Print.
@article{419544,
  abstract     = {We measured the complex capacitance C(f) of ITO/sol-gel alumina/Al capacitors deposited on glass (and some on stainless steel foil) in the frequency range 15 Hz-10 MHz. The sol-gel films were deposited by dip-coating and following a two-step process. The capacitance C(f) found was much higher than that of a pure Al2O3-film due to the remaining porosity of the film and the uptake of H2O from the environment. The C(f) curves are useful as a sensitive probe for the porosity of the sol-gel film. In particular the evolution of the capacitance curve with time after drying has been measured. The curves can qualitatively be understood by modelling the capacitor as a (nearly) percolating random insulator/conductor network, using the effective medium approximation. However a detailed understanding of the relation between the C(f,t) curves and the structure of the films requires a more elaborate model. Films sintered at 500-550 degrees C for 1 h initially behave exactly as not sintered films but in contrast with the latter they improve slowly over time. Fast sintering yields better films.},
  author       = {De Visschere, Patrick and Vanbesien, Karel},
  issn         = {0928-0707},
  journal      = {JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY},
  keyword      = {thin film,sol-gel,capacitance,effective medium approximation,percolation,porosity,AL2O3 HUMIDITY SENSOR,CERAMIC SENSORS,IMPEDANCE,PERCOLATION,FILMS,SIMULATION,ELECTRODES,CONDUCTORS,DEPENDENCE,RESISTANCE},
  language     = {eng},
  number       = {3},
  pages        = {225--235},
  publisher    = {Springer},
  title        = {Capacitance spectroscopy of alumina sol-gel capacitors with Al top contacts},
  url          = {http://dx.doi.org/10.1007/s10971-008-1687-2},
  volume       = {45},
  year         = {2008},
}

Altmetric
View in Altmetric
Web of Science
Times cited: