Electrical Properties of Li-doped P-type ZnO Ceramics

摘要

Li-doped p-type ZnO ceramics were prepared by conventional methods according to the chemical formula Zn1-xLixO2 where x=0.5, 1.0, 1.5 and 2.0 mole fraction, respectively. The crystal structures of the prepared samples were studied by X-ray diffraction analysis. The dielectric properties (including dielectric constant ε and dielectric loss ε ) and dc-electrical conductivity [σ(Ω-1·cm-1)] were investigated. The dielectric constant ε was sharply decreased at the low frequency range and independent on frequency at high frequency range. Otherwise, the dielectric loss ε varied with frequency and showed absorption peak located from 200 Hz to 4 kHz and moved to higher frequency as the concentration of Li+ doped increased. It was found that dcelectrical conductivity logσ varied from -9 to ?5 and the energy gap width were calculated by using Arrhenius equation. The p-type conductivity of Li-doped ZnO may be attributed to the formation of a LiZn-Lii donor complex, which is limited by reducing the amount of Lii.