saujs Sakarya University Journal of Science 2147-835X Sakarya University 10.16984/saufenbilder.322378 Metrology, Applied and Industrial Physics Metroloji,Uygulamalı ve Endüstriyel Fizik Meyer-Neldel rule in ac conductivity of Cu doped ZnO thin films Meyer-Neldel Rule in Ac Conductivity of Cu Doped ZnO Thin Films Can Nursel Yildiz Technical University Can Ömür Birsel Yildiz Technical University Altındal Ahmet Yildiz Technical University 12 01 2018 22 6 1538 1543 06 19 2017 01 13 2018 Copyright © 1997, Sakarya University Journal of Science 1997 Sakarya University Journal of Science

Ac charge transport mechanisms have been comparatively investigated in ZnO thinfilms having different Cu dopant. A comparative study of the applicability of quantummechanical tunelling and correlated barrier hopping model to obtained ac electricalconductivity results has been performed.Comparing the temperature dependence of the frequency exponent shows that the correlatedbarrier hopping model best describesthe experimental data on the ac conductivity in ZnO:Cu thin films. In order togain an understanding of the applicability of Meyer-Neldel rule, the dependenceof the thermal activation energy on Cu doping concentration in these films hasalso been studied. The obtained experimental results indicated thatMeyer-Neldel rule can be succesfully applied ac conductivity data for highly Cudoped films but not others which has been explained on the basis ofdistribution variations in density of states.

Ac charge transport mechanisms have been comparatively investigated in ZnO thinfilms having different Cu dopant. A comparative study of the applicability of quantummechanical tunelling and correlated barrier hopping model to obtained ac electricalconductivity results has been performed.Comparing the temperature dependence of the frequency exponent shows that the correlatedbarrier hopping model best describesthe experimental data on the ac conductivity in ZnO:Cu thin films. In order togain an understanding of the applicability of Meyer-Neldel rule, the dependenceof the thermal activation energy on Cu doping concentration in these films hasalso been studied. The obtained experimental results indicated thatMeyer-Neldel rule can be succesfully applied ac conductivity data for highly Cudoped films but not others which has been explained on the basis ofdistribution variations in density of states.

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