Frequency dependent conductivity in As2Se3 and As2Se3 + 15% Sb

Dc and ac measurements were performed on bulk samples of undoped and 15% Sb doped As₂Se₃ as a function of temperature (90–400 K) and frequency (10³–10⁶ Hz). The dc results show an activated conductivity dependence on temperature with an activation energy of 0.8 eV above room temperature. The ac results give a temperature dependent frequency exponent s. The temperature dependence of G _ac is discussed in terms of the mechanisms involved. Results are compared with the predictions of the Quantum Mechanical Tunnelling and Correlated Barrier Hopping models. It is found that doping increases the dc conductivity but has no effect on the ac conductivity.