Effect of annealing on spray deposited Ni-Zn ferrite thin films

Abstract

The thin films of Ni-Zn ferrite have been synthesized using spray pyrolysis technique onto the glass substrate. The as deposited films are found to be amorphous and the films become crystalline after annealing them in the temperature range 400-600^oC in the steps of 100^oC for 6 h. It is found that the crystallinity increases with annealing temperature. Further for the film annealed at 600^oC, some additional XRD peaks of the glass substrate have been observed.

Therefore, the films annealed at 500^oC<i> </i>are characterized further by EDAX technique. The elemental analysis by EDAX confirms the stoichiometric formation of Ni-Zn ferrite. The resistivity for all the samples with respect to temperature shows rapid decrease in resistivity at around 180^oC. This may be due to oxido-reduction process that appears during heating of ferrite sample in the air. 3Fe²⁺ ↔2Fe³⁺ total reaction takes place in the temperature range 100-250^oC. However, there is no much difference in the resistivity value at room temperature for these samples.