Abstract
Tin doped indium oxide (ITO) thin films were prepared by sol–gel spin coating method with In (NO3)·3H2O and SnCl4·5H2O as indium and tin sources, respectively. The as deposited samples were annealed at various temperature such as, 300, 400, 500 and 600 °C for 2 h in ambient atmosphere. The grown ITO thin films are polycrystalline in nature with cubic structure of In2O3 with the space group La3 and the results are in good agreement with the standard JCPDS data (card no#06-0416). In addition crystalline size increases with increasing annealing temperature from 25 to 55 nm. Polycrystalline with uniform smooth surface was observed by SEM micrographs. The optical band gap energy was found to be decreased from 3.85 to 3.23 eV as the annealing temperature is increased from 300 to 600 °C. The humidity sensing performance (high sensitivity and fast response time) was significantly improved for 600 °C thin films samples, which is probably due to smaller energy band gap and physisorption between the water molecules and the surface of the thin films. The films were further characterized by PL and EDS analysis. The effect of temperature on humidity sensing mechanism of ITO thin films is also discussed.
Similar content being viewed by others
References
E. Abad, S. Zampolli, S. Macro, A. Scorzoni, B. Mazzolai, A. Juarros, D. Gómez, I. Elmi, G.C. Cardinali, J.M. Gómez, F. Palacio, M. Cicioni, A. Mondini, T. Becker, I. Sayhan, Sens. Actuators B 127, 2–7 (2007)
A. Vergara, E. Llobet, J.L. Ramírez, P. Ivanov, L. Fonseca, S. Zampolli, A. Scorzoni, T. Becker, S. Marco, J. Wöllenstein, Sens. Actuators B 127, 143–149 (2007)
M.C. Mcalpine, H. Ahmad, D. Wang, J.R. Heath, Nat. Mater. 16, 379–384 (2007)
Y. Sun, H.H. Wang, Adv. Mater. 19, 2818–2823 (2007)
N. Heilig, U. Barsan, M. Weimar, M. Schweizer-Berberich, J.W. Gardner, W. Gopel, Sens. Actuators B 43, 45–51 (1997)
K. Wetchakun, T. Samerjai, N. Tamaekong, C. Liewhiran, C. Siriwong, V. Kruefu, A. Wisitsoraat, A. Tuantranont, S. Phanichphant. Sens. Actuators B 160, 580–591 (2011)
N.G. Patel, P.D. Patel, S. V., Vaishnav., Sens. Actuators B 6, 180–189 (2003)
M. Parthibavarman, V. Hariharan, C. Sekar, Mater. Sci. Eng. C 31, 840–844 (2011)
V. Vasanthi Pillay, Sarita Goyal, Mater. Today 2, 4609–4619 (2015)
V.S. Vaishnav, S.G. Patel, J.N. Panchal, Sens. Actuators B 2016, 381–388 (2015)
M. Thirumoorthi, J. Thomas Joseph Prakash, J. Asian Ceram. Soc. 4, 124–132 (2016)
B.M. Babu, S. Vadivel, J. Mater. Sci. (2016). doi:10.1007/s10854-016-5816-3
M. Parthibavarman, K. Vallalperuman, S. Sathishkumar, M. Durairaj, K. Thavamani, J. Mater. Sci. 25, 730–735 (2014)
Z.S. Seddigi, Bull. Environ. Contam. Toxicol. 84, 564 (2010)
D. Madhan, M. Parthibavarman, P. Rajkumar, M. Sangeetha, J. Mater. Sci. 26, 6823–6830 (2015)
A. Umar, B. Karunagaran, E.K. Suh, Y.B. Hahn, Nanotechnology 17, 4072 (2006)
M. Parthibavarman, B. Renganathan, D. Sastikumar, Curr. Appl. Phys. 13, 1537–1544 (2013)
S. C. Nagaraju, Aashis S. Roy, J. B. Prasanna Kumar, Koppalkar R. Anilkumar, G. Ramagopal, J. Eng. 2014, Article ID 925020, 8 pages (2014)
M. Li, X.L. Chen, D.F. Zhang, W.Y. Wang, W.J. Wang, Sens. Actuators B 147, 447–452 (2010)
Li Dongmei, Jingjing Zhang, Wei wei, Jingran Zhou, Shanpeng Wen, Shengping Ruan, J. Mater. Sci. 26, 3083–3089 (2015)
T. Krishnakumar, R. Jayaprakash, N. Pinna, A. Donato, N. Donato, G. Micali, G. Neri, J. Sens. Article ID 980965, 7 (2009)
Y. Li, M.J. Yang, Y. She, Talanta 62, 707–712 (2004)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Premkumar, M., Vadivel, S. Effect of annealing temperature on structural, optical and humidity sensing properties of indium tin oxide (ITO) thin films. J Mater Sci: Mater Electron 28, 8460–8466 (2017). https://doi.org/10.1007/s10854-017-6566-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10854-017-6566-6