Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-24T21:02:22.076Z Has data issue: false hasContentIssue false

Amorphous to anatase transformation in atomic layer deposited titania thin films induced by hydrothermal treatment at 120 °C

Published online by Cambridge University Press:  31 January 2011

Zhaoming Zhang*
Affiliation:
Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Lucas Heights, New South Wales 2234, Australia
Gerry Triani
Affiliation:
Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Lucas Heights, New South Wales 2234, Australia
Liang-Jen Fan
Affiliation:
National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
*
a)Address all correspondence to this author:email: [email protected]
Get access

Abstract

Hydrothermal treatment has been applied successfully to convert amorphous titania films to crystalline anatase at 120 °C, a temperature compatible with most polymeric substrates. The amorphous films were deposited at 80 °C using atomic layer deposition (ALD). The crystallinity of the films was monitored by x-ray absorption near edge structure (XANES), and the film composition was determined by x-ray photoelectron spectroscopy (XPS). The effect of precursor chemistry and substrate material was investigated. It was found that titania films produced from Ti isopropoxide are easier to crystallize than those from Ti tetrachloride as the Ti precursor. The amorphous to crystalline transformation can be achieved more readily with films deposited on Si than polycarbonate substrates. The effect of a “seed” layer on the amorphous to crystalline transformation was also studied. Preformed anatase crystallites between the Si substrate and the amorphous film were shown to accelerate the crystallization process. The possible mechanisms responsible for the phase transformation are discussed.

Type
Articles
Copyright
Copyright © Materials Research Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Linsebigler, A.L., Lu, G.Q.Yates, J.T.: Photocatalysis on TiO2 surfaces—Principles, mechanisms, and selected results. Chem. Rev. 95, 735 1995CrossRefGoogle Scholar
2O’Regan, B.Grätzel, M.: A low-cost, high-efficiency solar-cell based on dye-sensitized colloidal TiO2 films. Nature 353, 737 1991CrossRefGoogle Scholar
3Li, B., Wang, L., Kang, B., Wang, P.Qiu, Y.: Review of recent progress in solid-state dye-sensitized solar cells. Sol. Energy Mater. Sol. Cells 90, 549 2006CrossRefGoogle Scholar
4Vicente, G. San, Morales, A.Gutierrez, M.T.: Preparation and characterization of sol-gel TiO2 antireflective coatings for silicon. Thin Solid Films 391, 133 2001Google Scholar
5Bonhôte, P., Gogniat, E., Grätzel, M.Ashrit, P.V.: Novel electrochromic devices based on complementary nanocrystalline TiO2 and WO3 thin films. Thin Solid Films 350, 269 1999CrossRefGoogle Scholar
6Aarik, J., Aidla, A., Mändar, H.Uustare, T.: Atomic layer deposition of titanium dioxide from TiCl4 and H2O: Investigation of growth mechanism. Appl. Surf. Sci. 172, 148 2001CrossRefGoogle Scholar
7Aarik, J., Aidla, A., Uustare, T.Sammelselg, V.: Morphology and structure of TiO2 thin films grown by atomic layer deposition. J. Cryst. Growth 148, 268 1995Google Scholar
8Aarik, J., Aidla, A., Uustare, T., Ritala, M.Leskelä, M.: Titanium isopropoxide as a precursor for atomic layer deposition: Characterization of titanium dioxide growth process. Appl. Surf. Sci. 161, 385 2000CrossRefGoogle Scholar
9Mitchell, D.R.G., Triani, G.Zhang, Z.: Hydrothermal crystallization of amorphous titania films deposited using low temperature atomic layer deposition. Thin Solid Films (in press; DOI: 10.1016/j.tsf.2008.04.052)Google Scholar
10Suntola, T.: Atomic layer epitaxy. Thin Solid Films 216, 84 1992Google Scholar
11Finnie, K.S., Triani, G., Short, K.T., Mitchell, D.R.G., Attard, D.J., Bartlett, J.R.Barbé, C.J.: Influence of Si(100) surface pretreatment on the morphology of TiO2 films grown by atomic layer deposition. Thin Solid Films 440, 109 2003Google Scholar
12Latella, B.A., Triani, G., Zhang, Z., Short, K.T., Bartlett, J.R.Ignat, M.: Enhanced adhesion of atomic layer deposited titania on polycarbonate substrates. Thin Solid Films 515, 3138 2007CrossRefGoogle Scholar
13Lai, L.J., Tseng, P.C., Yang, Y.W., Chung, S.C., Song, Y.F., Cheng, N.F., Chen, C.C., Chen, C.T.Tsang, K.L.: Current status of the wide-range (10-1500ev) spherical grating monochromator beamline at SRRC. Nucl. Instrum. Methods Phys. Res., Sect. A 467–468, 586 2001CrossRefGoogle Scholar
14Brydson, R., Sauer, H., Engel, W., Thomas, J.M., Zeitler, E., Kosugi, N.Kuroda, H.: Electron-energy loss and x-ray absorption-spectroscopy of rutile and anatase—A test of structural sensitivity. J. Phys. Condens. Matter 1, 797 1989CrossRefGoogle Scholar
15Mitchell, D.R.G., Attard, D.J.Triani, G.: Transmission electron microscopy studies of atomic layer deposition TiO2 films grown on silicon. Thin Solid Films 441, 85 2003CrossRefGoogle Scholar
16Döring, H., Hashimoto, K.Fujishima, A.: TiO2 thin-films prepared by pulsed-beam chemical vapor-deposition from titanium tetraisopropoxide and water. Ber. Bunsen-Ges. Phys. Chem. 96, 620 1992Google Scholar
17Xie, Q., Jiang, Y-L., Detavernier, C., Deduytsche, D., Van Meirhaeghe, R.L., Ru, G-P., Li, B-Z.Qu, X-P.: Atomic layer deposition of TiO2 from tetrakis-dimethyl-amido titanium or Ti isopropoxide precursors and H2O. J. Appl. Phys. 102, 083521 2007CrossRefGoogle Scholar
18Ritala, M., Leskelä, M., Niinistö, L.Haussalo, P.: Titanium isopropoxide as a precursor in atomic layer epitaxy of titanium-dioxide thin-films. Chem. Mater. 5, 1174 1993CrossRefGoogle Scholar
19Rahtu, A.Ritala, M.: Reaction mechanism studies on titanium isopropoxide-water atomic layer deposition process. Chem. Vap. Deposition 8, 21 2002Google Scholar
20Hofmann, S.: Depth profiling in Practical Surface Analysis, 2nd ed., edited by D. Briggs and M.P. Seah John Wiley & Sons Chichester 1990 143Google Scholar
21Degroot, F.M.F., Faber, J., Michiels, J.J.M., Czyzyk, M.T., Abbate, M.Fuggle, J.C.: Oxygen 1s x-ray-absorption of tetravalent titaniumoxides—A comparison with single-particle calculations. Phys. Rev. B 48, 2074 1993Google Scholar
22Soriano, L., Abbate, M., Vogel, J., Fuggle, J.C., Fernández, A., González-Elipe, A.R., Sacchi, M.Sanz, J.M.: Chemical-changes induced by sputtering in TiO2 and some selected titanates as observed by x-ray-absorption spectroscopy. Surf. Sci. 290, 427 1993Google Scholar
23Kucheyev, S.O., van Buuren, T., Baumann, T.F., Satcher, J.H., Willey, T.M., Meulenberg, R.W., Felter, T.E., Poco, J.F., Gammon, S.A.Terminello, L.J.: Electronic structure of titania aerogels from soft x-ray absorption spectroscopy. Phys. Rev. B 69, 245102 2004CrossRefGoogle Scholar
24van der Laan, G.: Polaronic satellites in x-ray-absorption spectra. Phys. Rev. B 41, 12366 1990CrossRefGoogle Scholar
25Okada, K.Kotani, A.: Theory of core-level x-ray photoemission and photoabsorption in Ti compounds. J. Electron. Spectrosc. Relat. Phenom. 62, 131 1993Google Scholar
26Degroot, F.M.F., Figueiredo, M.O., Basto, M.J., Abbate, M., Petersen, H.Fuggle, J.C.: 2p x-ray absorption of titanium in minerals. Phys. Chem. Miner. 19, 140 1992Google Scholar
27Crocombette, J.P.Jollet, F.: Ti 2p x-ray absorption in titanium dioxides (TiO2): The influence of the cation site environment. J. Phys. Condens. Matter 6, 10811 1994CrossRefGoogle Scholar
28Park, S., Clark, B.L., Keszler, D.A., Bender, J.P., Wager, J.F., Reynolds, T.A.Herman, G.S.: Low-temperature thin-film deposition and crystallization. Science 297, 65 2002Google Scholar
29Lu, C.H., Chen, Y.C.Sun, Y.C.: Low-temperature crystallization of electroceramic thin films at elevated pressure. J. Mater. Chem. 12, 1628 2002Google Scholar
30Lu, C.H.Wu, W.H.: Photocatalytic TiO2 thin films prepared via a high-pressure crystallization process. Mater. Sci. Eng., B 113, 42 2004CrossRefGoogle Scholar
31Imai, H., Morimoto, H., Tominaga, A.Hirashima, H.: Structural changes in sol-gel derived SiO2 and TiO2 films by exposure to water vapor. J. Sol-Gel Sci. Technol. 10, 45 1997CrossRefGoogle Scholar
32Zhang, D.S., Yoshida, T.Minoura, H.: Low-temperature fabrication of efficient porous titania photoelectrodes by hydrothermal crystallization at the solid/gas interface. Adv. Mater. 15, 814 2003CrossRefGoogle Scholar
33Exarhos, G.J., Hess, N.J.Wood, S.: Transient stress evolution and crystallization in laser-irradiated amorphous titania sol-gel films in Laser-Induced Damage in Optical Materials:, 1991 edited by H.E. Bennett, L.L. Chase, A.H. Guenther, B.E. Newnam, and M.J. Soileau (Proc. SPIE 1624, Boulder, CO, 1992), p. 444CrossRefGoogle Scholar