Meyer-Neldel rule in ac conductivity of Cu doped ZnO thin films

Year 2018, Volume: 22 Issue: 6, 1538 - 1543, 01.12.2018

Nursel Can , Birsel Can Ömür Ahmet Altındal

https://doi.org/10.16984/saufenbilder.322378

Abstract

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

Keywords

Meyer-Neldel rule, transport mechanism, ZnO

Meyer-Neldel Rule in Ac Conductivity of Cu Doped ZnO Thin Films

Abstract

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

Keywords

Meyer-Neldel rule, ac charge transport mechanism, ZnO, thin film

References

• Y. S. Kim and W. P. Tai, “Electrical and optical properties of Al doped ZnO thin films by sol-gel process”, Applied Surface Science, vol. 253, pp. 4911– 4916, 2007.
• J. Xu, J. Han, Y. Zhang, Y. Sun, and B. Xie, “Studies on alcohol sensing mechanism of ZnO based gas sensors”, Sensors Actuators B: Chemical, vol. 132, pp. 334–339, 2008.
• K. L. Chopra, S. Major, and D. K. Pandya, “Transparent conductors-a status review”, Thin Solid Films, vol. 102, pp. 1–46, 1983.
• Z. Yang, Y. Huang, G. Chen, Z. Guo, S. Cheng, and S. Huang, “Ethanol gas sensor based on Al-doped ZnO nanomaterial with many gas diffusing channels”, Sensors and Actuators B: Chemical, vol. 140, pp. 549–556, 2009.
• Y. Dai, Y. Zhang, Q. K. Li, and C.W. Nan, “Synthesis and optical properties of tetrapod-like zinc oxide nanorods”, Chemical Physics Letters, vol. 358, pp. 83–86, 2002.
• H. Sato, T. Minami, Y. Tamura, S. Sakata, T. Mori, and N. Ogawa “Aluminium content dependence of milky transparent conducting ZnO:Al films with textured surface prepared by d.c. magnetron sputtering”, Thin Solid Films, vol. 246, pp. 86–91, 1994.
• P. K. Song, M. Watanabe, M. Kon, A. Mitsui, and Y. Shigesato, “Electrical and optical properties of gallium-doped zinc oxide films deposited by dc magnetron sputtering”, Thin Solid Films, vol. 411, pp. 82–86, 2002.
• G. G. Valle, P. Hammer, S. H. Pulcinelli, and C. V. Santilli, “Transparent and conductive ZnO:Al thin films prepared by sol-gel dip-coating”, Journal of the European Ceramic Society, vol. 24, pp. 1009–1013, 2004.
• Z. Q. Ma, W. G. Zhao, and Y. Wang, “Electrical properties of Na/Mg co-doped ZnO thin films”, Thin Solid Films, vol. 515, pp. 8611–8614, 2007.
• A. E. Jimenez-Gonzalez, J. A. Soto Ureuta, and R. Suarez-Parra, “Optical and electrical characteristics of aluminum-doped ZnO thin films prepared by solgel technique”, Journal of Crystal Growth, vol. 192, pp. 430–438, 1998.
• U. Wahl, E. Rita, J. G. Correia, E. Alves, and J. P. Araujo, “Implantation site of rare earths in single-crystalline ZnO”, Applied Physics Letters, vol. 82, pp. 1173–1175, 2003.
• R. Kaur, A. V. Singh, and R. M. Mehra, “Structural, electrical and optical properties of sol–gel derived yttrium doped ZnO films”, Physica Status Solidi (a), vol. 202, pp. 1053–1059, 2005.
• S. R. Elliott, A theory of a.c. conduction in chalcogenide glasses”, Philosophical Magazine, vol. 36, pp. 1291–1304, 1977.
• S. R. Lukić-Petrović, F. Skuban, D. M. Petrović, and M. Slankamenac, “Effect of copper on DC and AC conductivities of (As2Se3)–(AsI3) glassy semiconductors”, Journal of Non-Crystalline Solids, vol. 356, pp. 2409–2413, 2010.
• A. Altındal, Ş. Abdurrahmanoğlu, M. Bulut, and Ö. Bekaroğlu, “Charge transport mechanism in bis(double-decker lutetium(III) phthalocyanine) (Lu2Pc4) thin film”, Synthetic Metals, vol. 150, pp. 181–187, 2005.
• N. Kılınç, S. Öztürk, L. Arda, A. Altındal, and Z. Z. Öztürk, “Structural, electrical transport and NO2 sensing properties of Y-doped ZnO thin films”, Journal of Alloys and Compounds, vol. 536, pp. 138–144, 2012.
• W. Meyer and H. Neldel, “Über die beziehungen zwischen der energiekonstanten e under der mengenkonstanten a in der leitwerts-temperaturformel bei oxydischen halbleitern”, Z. Techn. Phys B, vol. 18, pp. 588– 593, 1937.
• J. W. Niemantsverdriet, K. Markert, and K. Wandelt, “The compensation effect and the manifestation of lateral interactions in thermal desorption spectroscopy”, Applied. Surface Science,vol. 31, pp. 211–219, 1988.
• W. Bogusz, D. E. Kony, and F. Krok, “Application of the Meyer-Neldel rule to the electrical conductivity of Nasicon”, Materials Science and Engineering B, vol. 15, pp. 169–172, 1992.
• P. H. Fang, “A model of Meyer-Neldel rule”, Physics Letters A, vol. 30, pp. 217–218, 1969.
• N. Koga and J. Sestak, “Kinetic compensation effect as a mathematical consequence of the exponential rate constant”, Thermochimica Acta, vol. 182, pp. 201–208, 1991.
• G. G. Roberts, “Thermally assisted tunnelling and pseudointrinsic conduction: two mechanisms to explain the Meyer-Neldel rule”, Journal of Physics C: Solid State Physics, vol. 4, pp. 167–176, 1971.
• M. H. Cohen, E. N. Economou, and C. M. Soukoulis, “Electron transport in amorphous semiconductors”, Journal of Non-Crystalline Solids, vol. 66, pp. 285–290, 1984.
• G. Kemeny and G. B. Rosenberg, “Small Polarons in Organic and Biological Semiconductors”, The Journal of Chemical Physics, vol. 53, pp. 3549–3551, 1970.
• S. R. Elliott, Physics of Amorphous Materials, 2nd ed., Longman Group UK Limited, England, 1990.
• J. Stuke, “Problems in the understanding of electronic properties of amorphous silicon”, Journal of Non-Crystalline Solids, vol. 97–98, pp. 1–14, 1987.
• M. Kikuchi, “The Meyer–Neldel rule and the statistical shift of the Fermi level in amorphous semiconductors”, Journal of Applied Physics, vol.64, pp. 4997–5001, 1988.