SOL-JEL SPİN KAPLAMA YÖNTEMİYLE HAZIRLANMIŞ ZnO İNCE FİLMLERİN OPTİK ÖZELLİKLERİNİN İNCELENMESİ

Year 2015, Issue: 2015 Özel Sayısı, 147 - 156, 15.01.2016

Tacettin Yıldırım , Aliye Çankaya İlker Öcalan

Abstract

Sol-jel spin kaplama yöntemi kullanılarak ZnO ve
ZnO:N ince filmler kuartz altlık üzerine hazırlandı. ZnO ince filmlere hava
ortamında 400 ^oC’de ZnO:N ince filmlere ise N ortamında 700 ^oC
sıcaklıkta 2 saat tavlama işlemi yapıldı. Hazırlanan ZnO ve ZnO:N ince
filmlerin başlangıç çözeltisindeki N oranına göre yapısal, yüzeysel ve optik
özellikleri x-ışını kırınımı (XRD), taramalı elektron mikroskobu (SEM) ve optik
soğurma ölçümleriyle incelendi. N oranı arttıkça örneklerin yapısal, yüzeysel
ve optik özelliklerinde değişimler olduğu ve bant aralığı değerinin oda
sıcaklığında 30 meV azaldığı görüldü.

Keywords

ZnO ve ZnO:N ince filmler, Döndürerek kaplama, XRD, SEM, Optik özellikler

AN INVESTIGATION OF OPTICAL PROPERTIES OF ZnO THIN FILMS PREPARED USING SOL GEL SPIN COATING METHOD

Abstract

ZnO and ZnO:N thin films were prepared on quartz
glass using the sol gel spin coating methods. ZnO thin films at 400 ^oC
in air atmospher and ZnO:N thin films in Nitrogen Atmosphere at temperature of
700 ^oC were annealed for 2 h. The effect
of nitrogen rate in precursor on structural, morphological
and optical properties of the ZnO thin films was investigated by X-ray diffraction (XRD),
Scanning Electron Microscope (SEM) and Optical Absorption Measurements. It has
been observed that the structural, morphological
and optical properties of the ZnO thin films change as N
rate increases, and bandgap energy of thin films decreases by 30 meV at room
temperature.

Keywords

ZnO and ZnO:N thin films, Sol-gel spin coating, XRD, SEM, Optical properties

References

• [1] T. Aoki, Y. Hatanaka, and D. C. Look, ZnO diode fabricated by excimer-laser doping, Appl. Phys. Lett., 76, 3257, (2000).
• [2] X.-L. Guo, J.-H. Choi, H. Tabata, and T. Kawai, Fabrication and Optoelectronic Properties of a Transparent ZnO Homostructural Light-Emitting Diode, Jpn. J. Appl. Phys., Part 2 40, L177, (2001).
• [3] H. Ohta, M. Orita, M. Hirano, and H. Hosono, Fabrication and characterization of ultraviolet-emitting diodes composed of transparent p-n heterojunction, p-SrCu2O2 and n-ZnO, J. Appl. Phys. 89, 5720, (2001).
• [4] Ya. I. Alivov, J. E. Van Nostrand, D. C. Look, M. V. Chukichev, and B. M. Ataev, Observation of 430 nm electroluminescence from ZnO/GaN heterojunction light-emitting diodes, Appl. Phys. Lett. 83, 2943, (2003).
• [5] S. Tüzemen, E. Gür, T. Yıldırım, G. Xiong and R. T. Williams, An investigation of control mechanisms of the excitonic behavior in reactively sputtered ZnO on (0001) Al2O3, J. Appl. Phys, 100, 103513, (2006).
• [6] T. Yıldırım, E. Gür, S. Tüzemen, V. Bilgin, S. Köse, F. Atay and I. Akyüz, Wide-bandgap modificationof polycrystalline ZnO using Sn component on the basis of developing quantum-well hetero-structure, Physica E, 27, 290, (2005).
• [7] D. C. Look, Recent advances in ZnO materials and devices, Mater. Sci. Eng., B, 80, 383, 2001.
• [8]. W. Y. Liang and A. D. Yoffe, Transmission Spectra of ZnO Single Crystals, Phys. Rev. Lett. 20, 59,1968.
• [9] B.J. Jin, S.H. Bae, S.Y. Lee, S. Im, Effects of native defects on optical and electrical properties of ZnO prepared by pulsed laser deposition. Materials Science and Engineering B, 71, 301-305, 2000.
• [10] S.A.Studeniken, N.Golego, M. Cocivera, Optical and electrical properties of undoped ZnO films grown by spray pyrolysis of zinc nitrate solution. J. Appl. Phys., 83(4), 2104-2111, 1998.
• [11] A. Azam, F. Ahmed, N. Arshi, M. Chaman, A. H. Naqvi, Formation and characterization of ZnO nanopowder synthesized by sol-gel method, J Alloy Compd, 496, 399-402, 2010.
• [12] L. Znaidi, Sol-gel-deposited ZnO films: A review, Mater. Sci. Eng., B, 174, 18-30, 2010.
• [13] M. Sahal, B. Hartiti, A. Ridah, M. Mollar, B. Mari, Structural, electrical, and optical properties of ZnO thin films deposited by sol-gel, Microelectron J, 39, 1425-1428, 2008.
• [14] J. Lee, A. J. Easteal, U. Pal, D. Bhattacharyya, Evolution of ZnO nanostructures in sol-gel synthesis, current applied physics, 9, 792-796, 2009.
• [15] P. K Nayak,. J. Yang, J. Kim, S. Chung, J. Jaewook, L. Changhee, H. Yongtaek, Spin-coted Ga-doped znO transparent conducting thin films for organic light-emitting diodes, J. Phys. D: Appl. Phys., 42, 035102, (2009).
• [16] M. Fox, , Optical Properties of Solids, Oxford University Press,, p. 4, 115, London, 2001.
• [17] N. Serpone , D. Lawless , R. Khairutdinov, Size Effects on the Photophysical Properties of Colloidal Anatase TiO2 Particles: Size Quantization versus Direct Transitions in This Indirect Semiconductor? J. Phys. Chem., 99 (45), 16646–16654, 1995.
• [18] L. G. Wang and A. Zunger, Cluster-Doping Approach for Wide-Gap Semiconductors: The Case of p-Type ZnO, Phys. Rev. Lett.,90, 256401:1-4, 2003.
• [19] Y. Yan, S. B.Zhang, S. T. Pantelides, Control of Doping by Impurity Chemical Potentials: Predictions for p-Type ZnO, Phys. Rev. Lett.,86, 5723, 2001.