Effect of Deposition Temperature on the FTIR Absorbance of Zinc Oxide Thin Films Produced by MOCVD

U. S. Mbamara, G. A. Alozie, K. B. Okeoma, C. Iroegbu

Department of Physics, Federal University of Technology, Owerri, Nigeria.

DOI: 10.4236/jmp.2013.43048                

Abstract

Metalorganic chemical vapour deposition (MOCVD) method was used to deposit zinc oxide thin films on soda-lime glass substrates at temperatures of 330°C, 360°C, 390°C and 420°C, using zinc acetate as the precursor. Compressed air was used as the carrier gas at a flow rate of 2.5 dm³ per minute. Each deposition was carried out for two hours under atmospheric pressure. FTIR measurements were subsequently made on the produced thin films to determine their struc ture and trend with deposition temperatures. The measurements showed the presence of lingering functional groups of organic, oxide and nitride origin, which prominently moderated the natural vibrational modes of the material within their respective affiliate wavenumbers, as well as three slight but evident trends in absorbance peaks, cut-off wave length, and the existence of the functional groups with temperature. The produced materials are expected to be useful for enhanced solar cells, triggering sensor devices, p-doped zinc oxide, etc.

Keywords

ZnO Thin Films; MOCVD; Impurities; FTIR Absorbance; Applications

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Access Data, “Database of Select Committee on GRAS Substances, (SCOGS) Reviews,” 2009. http://www.accessdata.fda.gov/scripts/fcn/fcnDetailNavigation.cfm?rpt=scogsListing&id=372
[2]	U. S. Mbamara, O. O. Akinwunmi, E. I. Obiajunwa, I. A. O. Ojo and E. O. B. Ajayi, “Deposition and Characterization of N-doped ZnO Thin Films by MOCVD using Zinc Acetate—Ammonium Acetate Precursor,” Journal of Modern Physics, Vol. 3, No. 8, 2012, pp. 652-659. doi:10.4236/jmp.2012.38089
[3]	M. D. McCluskey and S. J. Jokela, “Sources of n-Type Conductivity in ZnO,” Physica B, Vol. 401-402, 2007, pp. 355-357. doi:10.1016/j.physb.2007.08.186
[4]	U. OzgUr, Y. I. Alivov, C. Liu, A. Teke, M. A. Reshchikov, S. Dogan, V. Avrutin and S. J. Cho, “A Comprehensive Review of ZnO Materials and Devices,” Journal of Applied Physics, Vol. 98, No. 4, 2005, Article ID: 041301. doi:10.1063/1.1992666
[5]	D. Scarano, S. Bertarione, F. Cesano, J. G. Vitillo and A. Zecchina, “Plate-like ZnO Microcrystals: Synthesis and Characterization of a Material Active Toward H Adsorption,” Catalysis Today, Vol. 116, No. 3, 2006, pp. 433- 438. doi:10.1016/j.cattod.2006.05.062
[6]	D. Look, “Recent Advances in ZnO Materials and Devices,” Materials Science and Engineering: B, Vol. 80, No. 1-3, 2001, pp. 383-387. doi:10.1016/S0921-5107(00)00604-8
[7]	H. T. Wang, B. S. Kang, F. Ren, L. C. Tien, P. W. Sadik, D. P. Norton, S. J. Pearton and J. Lin, “Hydrogen-Selective Sensing at Room Temperature with ZnO Nanorods,” Applied Physics Letters, Vol. 86, No. 24, 2005, Article ID: 243503. doi:10.1063/1.1949707
[8]	Science Daily, “New Small-Scale Generator Produces Alternating Current by Stretching Zinc Oxide Wires,” Science Daily, 2008. http://www.sciencedaily.com/releases/2008/11/081109193342.htm
[9]	A. C. Mofor, A. El-Shaer, A. Bakin, A. Waag, H. Ahlers, U. Siegner, S. Sievers and M. Albrecht, “Magnetic Property Investigations on Mn-Doped ZnO Layers on Sapphire,” Applied Physics Letters, Vol. 87, No. 6, 2005, Article ID: 062501. doi:10.1063/1.2007864
[10]	M. D. McCluskey, S. J. Jokela and K. K. Zhuravlev, P. J. Simpson and K. G. Lynn, “Infrared Spectroscopy of Hydrogen in ZnO,” Applied Physics Letters, Vol. 81, No. 20, 2002, pp. 3807-3809. doi:10.1063/1.1520703
[11]	T. Ohgaki, N. Ohashi, S. Sugimura, H. Ryoken, I. Sakaguchi, Y. Adachi and H. Haneda, “Positive Hall Coefficients Obtained from Contact Misplacement on Evident n-type ZnO Films and Crystals,” Journal of Materials Research, Vol. 23, No. 9, 2008, pp. 2293-2295. doi:10.1557/jmr.2008.0300
[12]	S. V. Prasad, S. D. Walck and J. S. Zabinski, “Microstructural Evolution in Lubricious ZnO Films Grown by Pulsed Laser Deposition,” Thin Solid Films, Vol. 360, No. 1-2, 2000, pp. 107-117.
[13]	J. S. Zabinski, J. Corneille, S. V. Prasad, N. T. McDevitt and J. B. Bultman, “Lubricious Zinc Oxide Films: Synthesis, Characterization and Tribological Behavior,” Journal of Materials Science, Vol. 32, No. 20, 1997, pp. 5313-5319. doi:10.1023/A:1018614811131
[14]	Z. Chai, X. Lu and D. He, “Atomic Layer Deposition of ZnO Films: Effects of Nanocrystalline Characteristics on Tribological Performance,” Surface and Coatings Technology, Vol. 207, 2012, pp. 361-366.
[15]	X. Li, B. Keyes, S. Asher, S. B. Zhang, S. Wei, T. J. Coutts, S. Limpijumnong and C. G. Van de Walle, “Hydrogen Passivation Effect in N-doped ZnO Thin Films,” Applied Physics, Vol. 86, 2005, Article ID: 122107. doi.org/10.1063/1.1886256
[16]	D. C. Look and B. Claflin, “p-Type Doping and Devices Based on ZnO,” Physica Status Solidi (b), Vol. 241, No. 3, 2004, pp. 624-630. doi:10.1002/pssb.200304271
[17]	D. C. Look, B. Claflin, Y. I. Alivov and S. J. Park, “The Future of ZnO Light Emitters,” Physica Status Solidi (a), Vol. 201, No. 10, 2004, pp. 2203-2212. doi:10.1002/pssa.200404803
[18]	X. Chen, Z. Zhang, B. Yao, M. Jiang, S. Wang, B. Li, C. Shan, L. Liu, D. Zhao and D. Shen, “Effect of Compressive Stress on Stability of N-doped p-type ZnO,” Applied Physics, Vol. 99, No. 9, 2011, Article ID: 091908. doi.org/10.1063/1.3631677
[19]	C. G. Van de Walle and J. Neugebauer, “First-principles Calculations for Defects and Impurities: Applications to III-nitrides,” Journal of Applied Physics, Vol. 95, No. 8, 2004, pp. 3851-3879. doi:10.1063/1.1682673
[20]	C. G. Van de Walle, “Theory of Hydrogen-Related Levels in Semiconductors and Oxides,” 2012. http://www.mrl.ucsb.edu/~vandewalle/IEDM120605_pdf
[21]	J. Robertson, R. Gillen and S. J. Clark, “Advances in Understanding of Transparent Conducting Oxides,” Thin Solid Films, Vol. 520, No. 10, 2012, pp. 3714-3720. doi.org/10.1016/j.tsf.2011.10.063
[22]	S. Limpijumnong, X. Li, S. Wei and S. B. Zhang, “Substitutional Diatomic Molecules NO, NC, CO, N2, and O2: Their Vibrational Frequencies and Effects on p-Doping of ZnO,” Applied Physics Letters, Vol. 86, No. 21, 2005, Article ID: 211910. doi:10.1063/1.1931823
[23]	G. A. Shi, M. Saboktakin, M. Stavola and S. J. Pearton, “Hidden Hydrogen in As-grown ZnO,” Applied Physics Letters, Vol. 85, No. 23, 2004, pp. 5601-5603. doi.org/10.1063/1.1832736
[24]	X. Li, S. E. Asher, B. M. Keyes, H. R. Moutinho, J. Luther and T. J. Coutts, “p-Type ZnO Thin Films Grown by MOCVD,” NREL/CP-520-37378, 2005.
[25]	C. G. Van de Walle, “Hydrogen as a Cause of Doping in Zinc Oxide,” Applied Physics Letters, Vol. 85, No. 5, 2000, pp. 1012-1015. doi:10.1103/PhysRevLett.85.1012
[26]	D. S. Kendall, “Infrared Spectroscopy of Coatings,” In: A. A. Tracton, Ed., Coatings Technology Handbook, 3rd Edition, CRC Press, Boca Raton, 2005. doi:10.1201/9781420027327.ch8
[27]	W. Jacob, A. Keudell and T. Schwarz-Selinger, “Infrared Analysis of Thin Films: Amorphous, Hydrogenated Carbon on Silicon,” Brazilian Journal of Physics, Vol. 30, No. 3, 2000.
[28]	B. M. Keyes, L. M. Gedvilas, X. Li and T. J. Coutts, “Infrared Spectroscopy of Polycrystalline ZnO and ZnO:N Thin Films,” Journal of Crystal Growth, Vol. 281, No. 2-4, 2005, pp. 297-302. doi:10.1016/j.jcrysgro.2005.04.053
[29]	D. Scarano, S. Bertarione, G. Spoto, A. Zecchina and C. Oter o Area′n, “FTIR Spectroscopy of H, CO, and Methane Adsorbed and Co-adsorbed on Zinc Oxide,” Thin Solid Films, Vol. 400, No. 1-2, 2001, pp. 50-55. doi.org/10.1016/S0040-6090(01)01472-9
[30]	J. Coates, “Interpretation of Infrared Spectra, a Practical Approach,” In: R. A. Meyers, Ed., Encyclopedia of Analytical Chemistry, John Wiley & Sons Ltd, Chichester, 2000, pp. 10815-10837.