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

Abstract

Effects of hydrogen plasma treatment on the electrical properties of a sol-gel-derived polycrystalline zinc oxide (ZnO) system have been studied by employing impedance spectroscopy. Complex impedance data were analyzed by employing an equivalent circuit. Hydrogen plasma treatment markedly increased the low-frequency range of constant values of the real part of complex impedance. As a result of plasma treatment, 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.