Spray pyrolytic deposition and characterization of lanthanum selenide (La2Se3) thin films

The versatile spray pyrolysis technique was employed to prepare thin films of lanthanum selenide (La2Se3) on glass and fluorine doped tin oxide (FTO) coated glass substrates under optimized conditions. The deposition temperature was 250 degreesC. The X-ray studies reveal that the films are polycrystalline with single La2Se3 phase. The estimated optical band gap was found to be 2.6 eV. The dielectric properties such as dielectric constant and dielectric loss of the films deposited on FTO coated glass substrates were measured with FTO-La2Se3-Ag structure as a function of frequency and the results are reported. At room temperature dielectric constant and dielectric loss for I kHz frequency were found to be 6.2 and 0.048, respectively. The room temperature electrical resistivity was of the order of 10(5) Omegacm. The La2Se3 films are found to be n-type semiconductor. (C) 2003 Elsevier Science B.V. All rights reserved.