Journal of Sol-Gel Science and Technology

, Volume 42, Issue 1, pp 89–93 | Cite as

Hafnia sol-gel films synthesized from HfCl4: Changes of structure and properties with the firing temperature

  • Tongjit Kidchob
  • Luca Malfatti
  • Filomena Serra
  • Paolo Falcaro
  • Stefano Enzo
  • Plinio Innocenzi


Thin sol-gel hafnia films have been synthesised from HfCl4, the synthesis has revealed to be a simple route to fabrication of hafnia films with high transparency in the UV-visible range. The films have been fired at different temperatures in air up to 1000°C and have been characterized by X-ray diffraction and Fourier transform infrared spectroscopy. Infrared absorption spectra of hafnia films have allowed to follow the formation of monoclinic crystalline phases together with XRD. Formation of monoclinic hafnia crystallites has been observed upon calcination at temperatures higher than 600°C, as shown by infrared spectroscopy and XRD.

The optical transmission and the refractive index as a function of the temperature of firing have been characterized by UV-Visible spectroscopy and spectroscopic ellipsometry. The hafnia films, after firing at 600°C, had a refractive index of 1.92 with a thickness of around 70 nm.


Hafnia Films Infrared spectroscopy XRD 



Luca Malfatti acknowledges Fondazione Elba (Italy) for financial support. FIRB 2001 Italian project is acknowledged for financial support (FIRB contract n. RBNE01P4JF).


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Copyright information

© Springer Science+Business Media, LLC 2006

Authors and Affiliations

  • Tongjit Kidchob
    • 1
  • Luca Malfatti
    • 1
  • Filomena Serra
    • 1
  • Paolo Falcaro
    • 2
  • Stefano Enzo
    • 3
  • Plinio Innocenzi
    • 1
  1. 1.Laboratorio di Scienza dei Materiali e Nanotecnologie, Dipartimento di Architettura e PianificazioneUniversità di Sassari and Nanoworld Institute, Palazzo Pou SalidAlghero (SS)Italy
  2. 2.Associazione CIVEN – Nano Fabrication FacilityMargheraItaly
  3. 3.Dipartimento di ChimicaUniversità di SassariSassariItaly

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