Abstract
In this paper, we report results of impedance measurements in polycrystalline diamond films deposited on n-Si using HF CVD method. The temperature was changed from 170 K up to RT and the scan frequency from 42 Hz to 5 MHz. The results of impedance measurement of the real and imaginary parts were presented in the form of a Cole–Cole plot in the complex plane. In the temperatures below RT, the observed impedance response of polycrystalline diamond was in the form of a single semicircular form. In order to interpret the observed response, a double resistor–capacitor parallel circuit model was used which allow for interpretation physical mechanisms responsible for such behavior. The impedance results were correlated with Raman spectroscopy measurements.