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Study of surface morphology and optical properties of Nb2O5 thin films with annealing

  • Gargi Agarwal
  • G. B. Reddy
Article

Abstract

Nb2O5 films have been deposited on variety of substrates using the sol-gel dip coating technique. As-deposited films on all substrates are amorphous. Films were annealed under controlled ambience at 300, 400 and 600°C for 5 h. As-deposited films on glass substrate show uniform surface structure. The crystal structure and surface topography are found to depend strongly on the annealing temperature and nature of the substrates. The average grain size of 40 nm is observed in films annealed at 300°C. On annealing at 400°C increasing grain size and resulting fusing of them, enhanced surface roughness. Films deposited on NaCl substrates crystallized into a stable monoclinic phase and those deposited on single crystal Si substrates crystallized into hexagonal phase after annealing at 600°C. The as-deposited films show very high transmittance (>90%) in the visible region. The optical band gap is observed to increase from 4.35 eV when the films are in amorphous state to 4.87 eV on crystallization.

Keywords

Surface Roughness Nb2O5 Hexagonal Phase Monoclinic Phase Control Ambience 
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References

  1. 1.
    R. C. Faria and Los Bulhões, J. Electrochem. Soc. 141 1994 L29.Google Scholar
  2. 2.
    M. A. Aegerter, Sol. Energy Mater. Sol. Cells 68 2001 401.Google Scholar
  3. 3.
    N. Özer, Din-Guo Chen and C. M. Lampert, Thin Solid Films 277 1996 162.Google Scholar
  4. 4.
    E. D. Palik, in “Handbook of Optical Constants of Solids,” edited by E. D. Palik Academic Press, NY, 1985.Google Scholar
  5. 5.
    2000 JCPDS—International Centre for Diffraction Data, Vol. 27-1312. and Vol. 28-0317.Google Scholar
  6. 6.
    1967 JCPDS-PDFS, Inorganic Volume, Vol. 6-10, 7-61.Google Scholar

Copyright information

© Springer Science + Business Media, Inc. 2005

Authors and Affiliations

  1. 1.Thin Film Laboratory, Department of PhysicsIndian Institute of TechnologyDelhiIndia

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