Characterization by the Impedance Spectroscopy of (ZnO)(X)(CdO)(1-X) Composite Thin Films

Abstract

The DC and AC electrical conduction of (ZnO)(X)(CdO)(1-X) thin films were investigated in this work. AC conductivity of (ZnO)(X)(CdO)(1-X) (X=0.2, 0.7) thin films was reported in the frequency range 5 Hz to 13 MHz and at the temperature of 20 °C, 40 °C and 60 °C using impedance spectroscopy. The main results were presented by frequency dependence of complex impedance real and imaginary parts of the samples and by Nycquist diagrams at different temperatures. Thin films electrical properties were determined, proposing an equivalent circuits constituted by resistances and capacities. The relaxation times values of (ZnO)(0.7)(CdO)(0.3) films computed suggested two relaxation process. The AC conductivity dependence on frequency and temperature revealed that a correlated barrier hopping model of the AC conduction was the most probable process in (ZnO)(0.7)(CdO)(0.3) films. Furthermore the calculated dielectric constants depended on frequency and temperature. The interfacial and orientation polarization contributed to the enhancement of the dielectric response of the two composites.

Keywords

• Complex impedance spectroscopy
• Thin films
• ZnO
• CdO
• AC conductivity.