Preparation of SrTiO3 thin films by spray pyrolysis technique and study of their structural and optical properties

Abstract

Strontium titanate polycrystalline thin films were prepared by sequent deposition of three TiO2/SrO/TiO2 layers using spray pyrolysis technique. Deposition parameters such as:  precursor solution, deposition temperature, flow rate of solution and annealing conditions were optimized to obtain homogeneous transparent films. Prepared thin films have granular microstructure. The optical transmittance and absorption spectra show that the films are absorber of the ultraviolet and transparent against visible lights. The transparency and grain size of the prepared samples increase by annealing process. The calculated optical band gap       (3.38 eV) is in good agreement with the existing data.

Keywords


[1] T. Hiibert, U. Beck, H. Kleinke, "Amorphous and nanocrystalline SrTiO3 thin films", J. of Non- Crystalline Solids 196 (1996) pp. 150-154.

[2] G. Brankovic, Z. Brankovic, J.A. Varela, E. Longo, "Strontium titanate prepared by spray pyrolysis", J. of the European Ceramic Society 24 (2004) pp. 989-991.

[3] F. M. Pontes, E. R. Leite, E. J. H. Lee, E. Longo, J. A. Varela, "Preparation, microstructural and electrical characterization of SrTiO3 thin films prepared by chemical route", Journal of the European Ceramic Society 21 (2001) pp. 419-426.

[4] G. M. Rae, S. B. Krupanidhib, "Study of electrical properties of Used excimer laser deposited strontium titanate films", J. Appl. Phys. 75 (1994) pp. 2604-2611.

[5] B. G. Almeida, A. Pietka, J. A. Mendes, "Infrared characterization of strontium titanate thin films", Applied Surface Science 238 (2004) pp. 395-399.

[6] L. Castañeda, J.C. Alonso, A. Ortiz, E. Andrade, "Spray pyrolysis deposition and characterization of titanium oxide thin films", Materials Chemistry and Physics77 (2002) pp. 938-944.

[7] M. N. Kamalasanan, N. Deepak Kumar, S. Chandra, "Structural, optical, and dielectric properties of sol-gel derived SrTiO3 thin films", J. Appl. Phys. 74 (1993) pp. 679-686.

[8] S. Saha, T. P. Sinha, A. Mookerjee, "Structural and optical properties of paraelectric SrTiO3", J. Phys. Condens. Matter 12 (2000) pp. 3325-3336.

[9] S. Sturm, A. Recnike, M. Ceh, "Nucleation and growth of planer faults in sro-excess SrTiO3", Journal of European Ceramic Society 21 (2001) pp. 2141-2144.

[10] M.O. Abou-Helal, W.T. Seeber, "Preparation of TiO2 thin films by spray pyrolysis to be used as a photocatalyst", Applied Surface Science 195 (2002) pp.53-62.

[11] R. Thomas, D. C. Du, M. N. Kamalasanan, S. Chandra, A. S. Bhalla, "Structural, electrical, and low-temperature dielectric properties of sol–gel derived SrTiO3 thin films", J. Appl. Phys. 82 (1997) pp. 4484-4488.