Effect of copper on impedance and dielectric studies of CuxZn1−xS mixed semiconductor compounds

Abstract Polycrystalline Cu x Zn 1−x S (0 ≤ x ≤ 0.1) semiconductor compound powders were prepared by controlled co-precipitation method in an alkaline medium using thiourea as a sulfide source. X-ray diffractograms of Cu x Zn 1−x S powders showed that they possess polycrystalline nature with Hexagonal crystalline structure. The frequency variation of AC conductivity of Cu x Zn 1−x S (0 ≤ x ≤ 0.1) compounds measured at different (30–300 °C) temperatures in the frequency range 5 kHz–20 MHz, showed two linear regions, (i) almost independent of frequency and (ii) an increasing region with the increase in frequency. Dielectric constant of all the compounds, measured at low frequencies, found to decrease with the increase in frequency and later, at higher frequencies it remained constant. The results are explained based on the copper interstitial defects formed due to addition of Cu into ZnS compound.