Last modified: 2018-07-23
Abstract
The development of multiple layers structures combining thin metal oxide and metal films (oxide/metal/oxide) is the most interesting alternative to improve the opto-electrical performances [1]. These structures have globally better characteristics than the attainable ones with a single type of material [2].
Previous research on ZnO/Metal/ZnO multilayer structures [3-10] have shown that the metal layer thicknesses of 5nm [11, 6, 12-14] and 10nm [15] exhibit the best opto-electrical performances.
In this work, ZnO/Al/ZnO multilayer films have successfully deposited on glass substrates by DC magnetron sputtering, at different ZnO thickness layers and Al thickness (5nm and 10nm). The XRD patterns have shown that the films were polycrystalline and hexagonal like Wurtzite structures, with preferential growth in the (002) plane. The results of the AFM roughness revealed that the Al layer addition makes the surface smoother that it meets the required conditions as the bottom electrode of organic light emitting diodes. The effects of Al film thickness on resistivity and optical transmittance are characterized and discussed. The maximum figure of merit value achieved is (3.9210-4 W-1) corresponding at the thicknesses (50nm/10nm/50nm) of ZnO/Al/ZnO structure respectively.
References
[1] S. Calnan, A. N. Tiwari, Thin Solid Films 518 (2010) 1839.
[2] S. Yang, Y. Zhang, D. Mo, Thin Solid Films 571 (2014) 605.
[3] K.Sivaramakrishnan, T. L. Alford, Applied Physics Letters 94 (2009) 052104.
[4] H. M. Lee, Y. J. Lee, I. S. Kim, M.S. Kang, S.B. Heo, Y.S. Kim, D. Kim; Vacuum 86 (2012) 1494.
[5] M. Girtan, Solar Energy Materials & Solar Cells 100 (2012) 153.
[6] D. R. Sahu, S. Y. Lin, J. L. Huang, Thin Solid Films 516 (2008) 4728.
[7] S. Song, T. Yang , M. Lv, Y. Li, Y. Xin, L. Jiang, Z. Wu, S. Han, Vacuum 85 (2010) 39.
[8] T. Yang, Z. Zhang, S. Song, Y. Li, M. Lv, Z. Wu, S. Han; Vacuum 83 (2009) 257.
[9] T. Dimopoulos, G. Z. Radnoczi, B. Pz, H. Brkl, Thin Solid Films 519 (2010) 1470.
[10] T. C. Lin, W. C Huang, F. C. Tsai, International Journal of Materials Science and Applications 3 (2014) 205.
[11] A. El Manounia, F. J. Manj, M. Mollar, B. Mar R. Gez, M. C. Lez, J. R. Ramos-Barrado; Superlattices and Microstructures 39 (2006) 185.
[12] E. Fortunato, L. Raniero, L. Silva, A. Gonlves, A. Pimentel, P. Barquinha, H. Aguas, L. Pereira, G. Gonlves, I. Ferreira, E. Elangovan, R. Martins, Sol. Engy. Mat. Sol. Cells 92 (2008) 1605.
[13] D. R. Sahu, J. L. Huang, Applied Surface Science 253 (2006) 915.
[14] P. K. Chiu, B. H.Liou, C. N. Hsiao, J. R. Yang, D. Chiang, W. H. Cho, C. T. Lee, Japanese Journal of Applied Physics 53 (2014) 05FF05.
[15] W. Huang, C. T. Pan, R-Y Yang; 19th International Workshop on Active-Matrix Flat panel Displays and Devices (AM-FPD); Publisher: IEEE, Kyoto, Vol. 91 (2012) ISBN: 978-1-4673-0399-6.