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Journal of Materials Science

, Volume 51, Issue 18, pp 8711–8717 | Cite as

Growth of highly textured iridium thin films and their stability at high temperature in oxygen atmosphere

  • L. Trupina
  • L. Nedelcu
  • C. Negrila
  • M. G. Banciu
  • L. Huitema
  • A. Crunteanu
  • M. Rammal
  • A. Ghalem
Original Paper

Abstract

The growth and thermal stability of textured iridium thin films used as bottom electrode in electronic devices based on ferroelectric materials were investigated. The thin films were grown using the dc magnetron sputtering technique. The Ir layers directly deposited on SiO2/Si substrates present a mixed (111) and (200) orientations, while the films grown on Ti seed layers exhibit a strong preferred (111) orientation favoured by good matching with the titanium lattice. The substrate temperature during the growth of iridium/titanium stack has a significant effect on the surface morphology of the iridium layer and its thermal stability. The as-grown surface of 20-nm-thick Ir films is smooth, having a root-mean-square (rms) roughness of 0.7 nm. After thermal annealing the Ir film shows an increased surface roughness due to the formation of agglomerations. The change in the surface morphology of the Ir layer is due to titanium diffusion and its oxidation. Thicker and better crystallised iridium thin films annealed in oxygen atmosphere at 700 °C show a good thermal stability with only a slight modification of the surface morphology. Within the limits of experimental error, there is no change in the electrical resistivity before and after thermal annealing. The rms roughness has not varied significantly and the XPS investigation shows no traces of titanium oxide on iridium surface. Ir/Ti stack deposited under the optimum conditions could be successfully used as electrode in devices based on oxide thin films.

Keywords

Iridium Bottom Electrode Oxide Thin Film Ferroelectric Thin Film Titanium Thin Film 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

This work was financially supported by the “Agence National de la Recherche” (ANR)-France and the National Authority for Scientific Research (ANCS)-Romania, under the project MAESTRO.

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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • L. Trupina
    • 1
  • L. Nedelcu
    • 1
  • C. Negrila
    • 1
  • M. G. Banciu
    • 1
  • L. Huitema
    • 2
  • A. Crunteanu
    • 2
  • M. Rammal
    • 2
  • A. Ghalem
    • 2
  1. 1.National Institute for Materials PhysicsBucharestRomania
  2. 2.XLIM UMR 7252 CNRS/University of LimogesLimogesFrance

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