Abstract
In this research, Al-doped (with 2, 4, 6, and 8 mol%) zinc oxide thin films deposited onto glass substrates using wet chemical spin coating technique were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and UV–Vis spectroscopic methods to realize the doping effect of Al on structural and optical properties of ZnO thin films. XRD analysis revealed that the Al-doped ZnO (AZO) thin films were polycrystalline in nature with hexagonal lattice structure, and crystallite growth along c-axis. SEM images on the film surface at lower Al content exhibited granular nanostructures. At higher Al content, the nanostructural features of ZnO thin films was observed to be diminished. The compositional analysis via EDS measurements indicated the presence of zinc, oxygen, and aluminium into the AZO thin films. AZO thin film containing 2 mol% Al exhibited higher transmittance of 97% and absorption edge at 385 nm in the visible region. Optical bandgaps of AZO thin films were varied within 3.30–3.37 eV. Noticeable variations on structural features, and optical parameters of AZO thin films were detected, and the changing trend showed was non-linear and non-monotonic in nature.
Graphic Abstract
Similar content being viewed by others
References
K. Huang, Z. Tang, L. Zhang, J. Yu, J. Lv, X. Liu, F. Liu, Preparation and characterization of Mg-doped ZnO thin films by sol–gel method. Appl. Surf. Sci. 258(8), 3710–3713 (2012)
M. Caglar, S. Ilican, Y. Caglar, Influence of dopant concentration on the optical properties of ZnO: In films by sol–gel method. Thin Solid Films 517(17), 5023–5028 (2009)
R.B. Kale, S.-Y. Lu, Hydrothermal growth and characterizations of dandelion-like ZnO nanostructures. J. Alloy Compd. 579, 444–449 (2013)
T. Prasada Rao, M.C. Santhosh Kumar, A. Safarulla, V. Ganesan, S.R. Barman, C. Sanjeeviraja, Physical properties of ZnO thin films deposited at various substrate temperatures using spray pyrolysis. Phys B Phys Condens Matter 405(9), 2226–2231 (2010).
K. Baba, C. Lazzaroni, M. Nikravech, ZnO and Al doped ZnO thin films deposited by Spray Plasma: effect of the growth time and Al doping on microstructural, optical and electrical properties, Thin Solid Films 595(PA), 129–135 (2015)
S. Benramache, F. Chabane, B. Benhaoua, F.Z. Lemmadi, Influence of growth time on crystalline structure, conductivity and optical properties of zno thin films. J. Semicond. 34(2), 023001 (2013)
S.S. Badadhe, I.S. Mulla, Effect of aluminium doping on structural and gas sensing properties of zinc oxide thin films deposited by spray pyrolysis (Report). Sens. Actuators B Chem. 156(2), 943 (2011)
B. Sernelius, K. Berggren, Z. Jin, I.I. Hamberg, C.G. Granqvist, Band-gap tailoring of ZnO by means of heavy Al doping. Phys. Rev. B Condens. Matter 37(17), 10244–10248 (1988)
M.S. Hossain, H. Kabir, M.M. Rahman, K. Hasan, M.S. Bashar, M. Rahman, M.A. Gafur, S. Islam, A. Amri, Z.-T. Jiang, M. Altarawneh, B.Z. Dlugogorski, Understanding the shrinkage of optical absorption edges of nanostructured Cd-Zn sulphide films for photothermal applications. Appl. Surf. Sci. 392, 854–862 (2017)
P. Mbule, D. Wang, R. Grieseler, P. Schaaf, B. Muhsin, H. Hoppe, B. Mothudi, M. Dhlamini, Aluminum-doped ZnO thin films deposited on flat and nanostructured glass substrates: quality and performance for applications in organic solar cells. Sol. Energy 172, 219–224 (2018)
S. Salam, M. Islam, A. Akram, Sol–gel synthesis of intrinsic and aluminum-doped zinc oxide thin films as transparent conducting oxides for thin film solar cells, Thin Solid Films 529(C), 242–247 (2013).
A. Crossay, S. Buecheler, L. Kranz, J. Perrenoud, C.M. Fella, Y.E. Romanyuk, A.N. Tiwari, Spray-deposited Al-doped ZnO transparent contacts for CdTe solar cells. Sol. Energy Mater. Sol. Cells 101, 283–288 (2012)
E. Gilardi, E. Fabbri, L. Bi, J.L.M. Rupp, T. Lippert, D. Pergolesi, E. Traversa, Effect of dopant-host ionic radii mismatch on acceptor-doped barium zirconate microstructure and proton conductivity. J. Phys. Chem. C 121(18), 9739–9747 (2017)
B.J. Babu, A. Maldonado, S. Velumani, R. Asomoza, Electrical and optical properties of ultrasonically sprayed Al-doped zinc oxide thin films. Mater. Sci. Eng. B Solid-State Mater. Adv. Technol. 174(1–3), 31–37 (2010)
E.O. Filatova, A.S. Konashuk, Interpretation of the changing the band gap of Al2O3 depending on its crystalline form: connection with different local symmetries. J. Phys. Chem. C 119(35), 20755–20761 (2015)
X.-R. Deng, H. Deng, M. Wei, Deep ultraviolet detecting property of AlxZn1−xO alloy thin film as photocathode layer. J. Alloy Compd. 563, 99–103 (2013)
E. Shaaban, M. El-Hagary, E. Moustafa, H. Hassan, Y. Ismail, M. Emam-Ismail, A. Ali, Structural, linear and nonlinear optical properties of co-doped ZnO thin films. Mater. Sci. Process. 122(1), 1–10 (2016)
M.A. Majeed Khan, S. Kumar, M. Naziruddin Khan, M. Ahamed, A.S. Al Dwayyan, Microstructure and blueshift in optical band gap of nanocrystalline AlxZn1−xO thin films, J. Lumin. 155, 275–281 (2014).
A. Illiberi, R. Scherpenborg, Y. Wu, F. Roozeboom, P. Poodt, Spatial atmospheric atomic layer deposition of Al(x)Zn(1–x)O. ACS Appl. Mater. Interfaces 5(24), 13124 (2013)
P.F. Carcia, R.S. McLean, M.H. Reilly, G. Nunes, Transparent ZnO thin-film transistor fabricated by rf magnetron sputtering. Appl. Phys. Lett. 82(7), 1117–1119 (2003)
K.D. Arun Kumar, V. Ganesh, S. Valanarasu, M. Shkir, I. Kulandaisamy, A. Kathalingam, S. Alfaify, Effect of solvent on the key properties of Al doped ZnO films prepared by nebulized spray pyrolysis technique, Mater. Chem. Phys. 212, 167–174 (2018).
S. Pat, R. Mohammadigharehbagh, S. Özen, V. Şenay, H.H. Yudar, Ş. Korkmaz, The Al doping effect on the surface, optical, electrical and nanomechanical properties of the ZnO and AZO thin films prepared by RF sputtering technique. Vacuum 141, 210–215 (2017)
B. Sonawane, M. Bhole, D. Patil, Structural, optical and electrical properties of post annealed Mg doped ZnO films for optoelectronics applications. Opt. Quant. Electron. 41(1), 17–26 (2009)
S.K. Min, G.Y. Kwang, L. Jae-Young, K. Soaram, N. Giwoong, Y.K. Do, K. Sung-O, L. Dong-Yul, S.K. Jin, S.K. Jong, Nanocrystalline ZnO thin films grown on porous silicon by sol–gel method and effects of post-annealing. J. Korean Phys. Soc. 59(2), 346 (2011)
Z.Q. Xu, H. Deng, Y. Li, Q.H. Guo, Y.R. Li, Characteristics of Al-doped c-axis orientation ZnO thin films prepared by the sol–gel method. Mater. Res. Bull. 41(2), 354–358 (2006)
S. Kurtaran, S. Aldag, G. Ofofoglu, I. Akyuz, F. Atay, On the role of Al in ultrasonically sprayed ZnO films. Mater. Chem. Phys. 185, 137–142 (2017)
C. Periasamy, P. Chakrabarti, Tailoring the structural and optoelectronic properties of Al-doped nanocrystalline ZnO thin films. J. Electron. Mater. 40(3), 259–266 (2011)
M. Shkir, M. Arif, V. Ganesh, M.A. Manthrammel, A. Singh, I.S. Yahia, S.R. Maidur, P.S. Patil, S. Alfaify, Investigation on structural, linear, nonlinear and optical limiting properties of sol–gel derived nanocrystalline Mg doped ZnO thin films for optoelectronic applications. J. Mol. Struct. 1173, 375–384 (2018)
Y. Caglar, M. Caglar, S. Ilican, Microstructural, optical and electrical studies on sol gel derived ZnO and ZnO: Al films. Curr Appl Phys 12(3), 963–968 (2012)
M. Pal, S. Bera, S. Sarkar, S. Jana, Influence of Al doping on microstructural, optical and photocatalytic properties of solgel based nanostructured zinc oxide films on glass. RSC Adv. 4(23), 11552–11563 (2014)
S. Mondal, S. Bhattacharyya, P. Mitra, Effect of Al doping on microstructure and optical band gap of ZnO thin film synthesized by successive ion layer adsorption and reaction. J. Phys. 80(2), 315–326 (2013)
H. Tong, Z. Deng, Z. Liu, C. Huang, J. Huang, H. Lan, C. Wang, Y. Cao, Effects of post-annealing on structural, optical and electrical properties of Al-doped ZnO thin films. Appl. Surf. Sci. 257(11), 4906–4911 (2011)
V.S. Rana, J.K. Rajput, T.K. Pathak, L.P. Purohit, Multilayer MgZnO/ZnO thin films for UV photodetectors. J. Alloy Compd. 764, 724–729 (2018)
K. Foo, U. Hashim, K. Muhammad, C. Voon, Sol–gel synthesized zinc oxide nanorods and their structural and optical investigation for optoelectronic application. Nanoscale Res. Lett. 9(1), 1–10 (2014)
M.N.H. Mia, M.F. Pervez, M.K. Hossain, M. Reefaz Rahman, M.J. Uddin, M.A. Al Mashud, H.K. Ghosh, M. Hoq, Influence of Mg content on tailoring optical bandgap of Mg-doped ZnO thin film prepared by sol-gel method, Results Phys. 7, 2683–2691 (2017).
J. Mohammad, S.M. Abed, Preparation and characterazation of aluminum doped nanocrystalline zinc oxide for solar cells applications. J. Ovonic Res. 15(1), 61–67 (2019)
X. Wang, K. Saito, T. Tanaka, M. Nishio, T. Nagaoka, M. Arita, Q. Guo, Energy band bowing parameter in MgZnO alloys. Appl. Phys. Lett. 107(2), 022111 (2015)
M.-W. Wu, P.-C. Tsai, Y.-C. Huang, Enhancement of the densification and mechanical properties of aluminum-doped zinc oxide ceramics by hot isostatic pressing. J. Alloy Compd. 650, 514–519 (2015)
G. Escalante, H. Juárez, M. Pacio, G. García, T. Díaz, E. Rosendo, A. Coyopol, Low temperature zno films deposited by sscvd. IOP Conf. Ser. Mater. Sci. Eng. 45(1), 012012 (2013)
H.-M. Zhou, D.-Q. Yi, Z.-M. Yu, L.-R. Xiao, J. Li, Preparation of aluminum doped zinc oxide films and the study of their microstructure, electrical and optical properties. Thin Solid Films 515(17), 6909–6914 (2007)
B.K. Sonawane, M.P. Bhole, D.S. Patil, Effect of magnesium incorporation in zinc oxide films for optical waveguide applications. Phys. B Phys. Condens. Matter 405(6), 1603–1607 (2010)
A. Zaiour, A. Benhaya, T. Bentrcia, Impact of deposition methods and doping on structural, optical and electrical properties of ZnO-Al thin films. Optik 186, 293–299 (2019)
D. Fang, C. Li, N. Wang, P. Li, P. Yao, Structural and optical properties of Mg-doped ZnO thin films prepared by a modified Pechini method. Cryst. Res. Technol. 48(5), 265–272 (2013)
M. Kashif, U. Hashim, M.E. Ali, S.M. Usman Ali, M. Rusop, Z.H. Ibupoto, M. Willander, Effect of Different seed solutions on the morphology and electrooptical properties of ZnO nanorods. J. Nanomater. 2012, 452407 (2012)
L. Xu, X. Li, Y. Chen, F. Xu, Structural and optical properties of ZnO thin films prepared by sol–gel method with different thickness. Appl. Surf. Sci. 257(9), 4031–4037 (2011)
R. Mariappan, V. Ponnuswamy, A. Chandra Bose, A. Chithambararaj, R. Suresh, M. Ragavendar, Structural, optical and electrical characterization of nebulizer-sprayed ZnO nano-rods, Superlattices Microstruct. 65, 184–194 (2014).
G. Srinivasan, R. Kumar, J. Kumar, Li doped and undoped ZnO nanocrystalline thin films: a comparative study of structural and optical properties. J. Sol-Gel Sci. Technol. 43(2), 171–177 (2007)
A. Taabouche, A. Bouabellou, F. Kermiche, F. Hanini, C. Sedrati, Y. Bouachiba, C. Benazzouz, Preparation and characterization of Al-doped ZnO piezoelectric thin films grown by pulsed laser deposition. Ceram. Int. 42(6), 6701–6706 (2016)
A. Nakrela, N. Benramdane, A. Bouzidi, Z. Kebbab, M. Medles, C. Mathieu, Site location of Al-dopant in ZnO lattice by exploiting the structural and optical characterisation of ZnO: Al thin films. Results Phys. 6, 133–138 (2016)
Ü. Özgür, Y.I. Alivov, C. Liu, A. Teke, M.A. Reshchikov, S. Doğan, V. Avrutin, S.J. Cho, H. Morkoç, A comprehensive review of ZnO materials and devices. J. Appl. Phys. 98(4), 041301 (2005)
S.K. Singh, P. Hazra, S. Tripathi, P. Chakrabarti, Optical characterization of Mg-doped ZnO thin films deposited by RF magnetron sputtering technique, AIP Conference Proceedings, AIP Publishing, 2016, p. 020168
J. Li, J. Xu, Q. Xu, G. Fang, Preparation and characterization of Al doped ZnO thin films by sol–gel process. J. Alloy Compd. 542, 151–156 (2012)
H. Karaagac, E. Yengel, M. Saif Islam, Physical properties and heterojunction device demonstration of aluminum-doped ZnO thin films synthesized at room ambient via sol–gel method, J. Alloys Compd. 521, 155–162 (2012).
D. Huang, X. Zeng, Y. Zheng, X. Wang, Y. Yang, Influence of process parameters on band gap of Al-doped ZnO film. Sel. Publ. Chin. Univ. 6(1), 114–121 (2013)
C.-M. Lai, K.-M. Lin, S. Rosmaidah, Effect of annealing temperature on the quality of Al-doped ZnO thin films prepared by sol–gel method. J. Sol-Gel Sci Technol. 61(1), 249–257 (2012)
N. Baydogan, O. Ozdemir, H. Cimenoglu, The improvement in the electrical properties of nanospherical ZnO: Al thin film exposed to irradiation using a Co-60 radioisotope, Radiat. Phys. Chem. 89(C), 20–27 (2013).
C.M. Muiva, T.S. Sathiaraj, K. Maabong, Effect of doping concentration on the properties of aluminium doped zinc oxide thin films prepared by spray pyrolysis for transparent electrode applications. Ceram. Int. 37(2), 555–560 (2011)
A.-S. Gadallah, M.M. El-Nahass, Structural, optical constants and photoluminescence of ZnO thin films grown by sol-gel spin coating. Adv. Condens. Matter. Phys. 2013, 234546 (2013)
Author information
Authors and Affiliations
Corresponding authors
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Mia, M.N.H., Habiba, U., Pervez, M.F. et al. Investigation of aluminum doping on structural and optical characteristics of sol–gel assisted spin-coated nano-structured zinc oxide thin films. Appl. Phys. A 126, 162 (2020). https://doi.org/10.1007/s00339-020-3332-z
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s00339-020-3332-z