Abstract
Epitaxial ZnO thin films were grown on (111) MgAl2O4 with a pre-seeded, two-step chemical solution deposition process. Isolated, epitaxial ZnO islands (seeds) were formed on the substrate in the first step by spin coating a very thin layer of the precursor solution and heat-treating to 950 °C/3 h. In the second step, the seeded substrate was coated with another layer of precursor to produce an epitaxial film. The result was compared with the case in which a MgAl2O4 substrate was not seeded. Both the seeded and unseeded ZnO films have out-of-plane and in-plane orientation relationships of (0001)ZnO ∥ (111)MgAl2O4 and [112̄0]ZnO ∥ [1̄1̄2]MgAl2O4, respectively. However, only the seeded ZnO films have very faceted surface morphology without grain boundaries, indicating epitaxy, whereas the unseeded ZnO films have deep grain boundaries indicative of polycrystalline nature. This result shows that the formation of seeds in the first step plays an instrumental role in the formation of an epitaxial ZnO film.
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References
C. Klingshirn: The luminescence of ZnO under high one- and two-quantum excitation. Phys. Status Solidi B 71, 547 (1975).
O. Yamazaki, T. Mitsuyu, and K. Wasa: ZnO thin-film SAW devices. IEEE Trans. Sonics Ultrason. SU-27, 369 (1980).
J. Ye, S. Gu, S. Zhu, T. Chen, L. Hu, F. Qin, R. Zhang, Y. Shi, and Y. Zheng: The growth and annealing of single crystalline ZnO films by low-pressure MOCVD. J. Cryst. Growth 243, 151 (2002).
P.M. Verghese and D.R. Clarke: Surface textured zinc oxide films. J. Mater. Res. 14, 1039 (1999).
H. Saeki, H. Tabata, and T. Kawai: Magnetic and electric properties of vanadium doped ZnO films. Solid State Commun. 120, 439 (2001).
Z.K. Tang, G.K.L Wong, P. Yu, M. Kawasaki, A. Ohtomo, H. Koinuma, and Y. Segawa: Room-temperature ultraviolet laser emission from self-assembled ZnO microcrystallite thin films. Appl. Phys. Lett. 72, 3270 (1998).
Y. Chen, S. Hong, H. Ko, M. Nakajima, T. Yao, and Y. Segawa: Plasma-assisted molecular-beam epitaxy of ZnO epilayers on atomically flat MgAl2O4(111) substrates. Appl. Phys. Lett. 76, 245 (2000).
Y. Igasaki and H. Saito: Substrate temperature dependence of electrical properties of ZnO:Al epitaxial films on sapphire (12̄10). J. Appl. Phys. 69, 2190 (1991).
Y.J. Kim and K.W. Kim: Characteristics of epitaxial ZnO films on sapphire substrates deposited using RF-magnetron sputtering. Jpn. J. Appl. Phys. 36(Part 1), 2277 (1997).
P. Kuppusami, G. Vollweiler, D. Rafaja, and K. Ellmer: Epitaxial growth of aluminium-doped zinc oxide films by magnetron sputtering on (001), (110), and (012) oriented sapphire substrates. Appl. Phys. A, Mater. Sci. & Proc. 80, 183 (2005).
M. Robien, W. Henrion, M. Bar, and C.H. Fischer: Optical properties of ZnO thin films: Ion layer gas reaction compared to sputter deposition. Appl. Phys. Lett. 80, 3518 (2002).
F.F. Lange: Chemical solution routes to single-crystal thin films. Science 273, 903 (1996).
T.P. Niesen and M.R. De Guire: Review: Deposition of ceramic thin films at low temperatures from aqueous solutions. Solid State Ionics 151, 61 (2002).
R.W. Schwartz, T. Schneller, and R. Waser: Chemical solution deposition of electronic oxide films. Comptes Rendus Chimie 7, 433 (2004).
M. Ohyama, H. Kozuka, and T. Yoko: Sol-gel preparation of ZnO films with extremely preferred orientation along (002) plane from zinc acetate solution. Thin Solid Films 306, 78 (1997).
Y. Kokubun, H. Kimura, and S. Nakagomi: Preparation of ZnO thin films on sapphire substrates by sol-gel method. Jpn. J. Appl. Phys. 42, L904 (2003).
R. Ghosh, B. Basak, and S. Fujihara: Effect of substrate-induced strain on the structural, electrical, and optical properties of polycrystalline ZnO thin films. J. Appl. Phys. 96, 2689 (2004).
B. Wessler, A. Steinecker, and W. Mader: Epitaxial growth of ZnO thin films on ScAlMgO4 (0 0 0 1) by chemical solution deposition. J. Cryst. Growth 242, 283 (2002).
B. Wessler, F.F. Lange, and W. Mader: Textured ZnO thin films on 0001 sapphire produced by chemical solution deposition. J. Mater. Res. 17, 1644 (2002).
D. Andeen, L. Loeffler, N. Padture, and F.F. Lange: Crystal chemistry of epitaxial ZnO on (1 1 1) MgAl2O4 produced by hydrothermal synthesis. J. Cryst. Growth 259, 103 (2003).
A. Seifert, A. Vojta, J.S. Speck, and F.F. Lange: Microstructural instability in single-crystal thin films. J. Mater. Res. 11, 1470 (1996).
J.H. Kim and F.F. Lange: Seeded epitaxial growth of PbTiO3 thin films on (001) LaAlO3 using the chemical solution deposition method. J. Mater. Res. 14, 1626 (1999).
K.T. Miller, F.F. Lange, and D.B. Marshall: The instability of polycrystalline thin films: Experiment and theory. J. Mater. Res. 5, 151 (1990).
C.V. Thompson, J. Floro, and H.I. Smith: Epitaxial grain growth in thin metal films. J. Appl. Phys. 67, 4099 (1990).
R.W. Schwartz, P.G. Clem, J.A. Voigt, E.R. Byhoff, M. Van Stry, T.J. Headley, and N.A. Missert: Control of microstructure and orientation in solution-deposited BaTiO3 and SrTiO3 thin films. J. Am. Ceram. Soc. 82, 2359 (1999).
K.T. Miller and F.F. Lange: Highly oriented thin films of cubic zirconia on sapphire through grain growth seeding. J. Mater. Res. 6, 2387 (1991).
T.A. Derouin, C.D.E Lakeman, X.H. Wu, J.S. Spectk, and F.F. Lange: Effect of lattice mismatch on the epitaxy of sol-gel LiNbO3 thin films. J. Mater. Res. 12, 1391 (1997).
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Kim, J.H., Kim, B., Andeen, D. et al. Seeded epitaxial growth of ZnO thin films on MgAl2O4 substrates using the chemical solution deposition method. Journal of Materials Research 22, 943–949 (2007). https://doi.org/10.1557/jmr.2007.0109
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DOI: https://doi.org/10.1557/jmr.2007.0109