Effects of hydrogen plasma treatment on sol-gel-derived ZnO studied by impedance spectroscopy

Effects of hydrogen plasma treatment on the electrical properties of a sol-gel-derived polycrystalline zinc oxide (ZnO) system have been studied by employing the impedance spectroscopy. The complex impedance data were analyzed by employing the equivalent circuits. Hydrogen plasma treatment markedly increased the low-frequency range of the constant values of the real part of the complex impedance. As a result of the plasma treatment, the electrical conductivity was found to increase by about two orders of magnitude, with the activation energy being reduced from 0.62 eV to 0.30 eV. The dielectric constant also showed a two-fold increase following the plasma treatment.