Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-19T08:44:09.160Z Has data issue: false hasContentIssue false
  • English
  • Français

Compositional Tailored Sol-Gel SiO2–TiO2 Thin Films: Crystallization, Chemical Bonding Configuration, and Optical Properties

Published online by Cambridge University Press:  03 March 2011

Li-Lan Yang ,
Yi-Sheng Lai ,
J.S. Chen ,
P.H. Tsai ,
C.L. Chen  and
C. Jason Chang
Li-Lan Yang
Affiliation:
Department of Materials Science and Engineering, National Cheng Kung University,Tainan, Taiwan, People’s Republic of China
Yi-Sheng Lai
Affiliation:
Department of Materials Science and Engineering, National Cheng Kung University,Tainan, Taiwan, People’s Republic of China
J.S. Chen
Affiliation:
Department of Materials Science and Engineering, National Cheng Kung University,Tainan, Taiwan, People’s Republic of China
P.H. Tsai
Affiliation:
Electronics Research & Service Organization, Industrial Technology Research Institute,Hsinchu, Taiwan, People’s Republic of China
C.L. Chen
Affiliation:
Electronics Research & Service Organization, Industrial Technology Research Institute,Hsinchu, Taiwan, People’s Republic of China
C. Jason Chang
Affiliation:
Electronics Research & Service Organization, Industrial Technology Research Institute,Hsinchu, Taiwan, People’s Republic of China
Get access

Abstract

Thin films of SiO2–TiO2 composite oxides with various SiO2:TiO2 compositions were prepared by the sol-gel method, using tetraethylorthosilicate (TEOS) and titanium tetraisopropoxide (TTIP) as precursors. The composition, crystal structure, and chemical bonding configuration of the as-deposited and annealed SiO2–TiO2 thin films were analyzed using Rutherford backscattering spectrometry (RBS), glancing incident angle x-ray diffraction (GIAXRD) and Fourier transform infrared spectroscopy (FTIR), respectively. Optical properties of the films were characterized by spectroscopic ellipsometry and ultraviolet-visible spectrophotometry. The Si/Ti ratios in the SiO2–TiO2 films agree with the TEOS/TTIP molar ratio in the sol-gel precursor. When the TEOS/(TEOS + TTIP) ratio is greater than 40%, the SiO2–TiO2 thin films remain amorphous (without formation of TiO2 crystalline phase) after annealing at temperatures as high as 700 °C. FTIR spectra indicate that the quantity of Si–O–Ti bonding can be maximized when the TEOS:TTIP in the precursor is 80%:20%. The refractive index of the SiO2–TiO2 films increases approximately linearly to the mixing ratio of TTIP/(TEOS + TTIP). However, SiO2-rich films possess higher ultraviolet-visible transmittance than the TiO2-rich films. The modification of microstructure and chemical bonding configuration in the SiO2–TiO2 films by the composition and its influence on the optical properties are discussed.

Keywords

Optical propertiesSol-gelThin film
Type
Articles
Information
Journal of Materials Research , Volume 20 , Issue 11 , November 2005 , pp. 3141 - 3149
Copyright
Copyright © Materials Research Society 2005

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

1Vörös, J., Ramsden, J.J., Csúcs, G., Szendrő, I., De Paul, S.M., Textor, M. and Spencer, N.D.: Optical grating coupler biosensor. Biomaterials 23, 3699 (2002).CrossRefGoogle Scholar
2Guenot, P.: Material aspects of standard transmission optical fibers. MRS Bull. 28(5), 360 (2003).CrossRefGoogle Scholar
3Jamois, C., Wehrspohn, R.B., Andreani, L.C., Hermann, C., Hess, O. and Gösele, U.: Silicon-based two-dimensional photonic crystal waveguides. Photon. Nanostruct. 1, 13 (2003).CrossRefGoogle Scholar
4Wang, X., Masumoto, H., Someno, Y. and Hirai, T.: Microstructure and optical properties of amorphous TiO2–SiO2 composite films synthesized by helicon plasma sputtering. Thin Solid Films 338, 105 (1999).CrossRefGoogle Scholar
5Laird, R. and Belkind, A.: Cosputtered films of mixed TiO2/SiO2. J. Vac. Sci. Technol. A 10, 1908 (1992).CrossRefGoogle Scholar
6Chen, J.S., Chao, S., Kao, J.S., Niu, H. and Chen, C.H.: Mixed films of TiO2–SiO2 deposited by double electron-beam coevaporation. Appl. Opt. 35, 90 (1996).CrossRefGoogle Scholar
7Hsu, L.S., Rujkorakarn, R., Sites, J.R. and She, C.Y.: Thermally induced crystallization of amorphous-titania films. J. Appl. Phys. 59, 3475 (1986).CrossRefGoogle Scholar
8Chao, S. and Wang, W.H.: Characteristics of ion-beam-sputtered high refractive index TiO2–SiO2 mixed films. J. Opt. Soc. Am. A 16, 1477 (1999).CrossRefGoogle Scholar
9Asano, S. and Sato, M.: Light scattering by randomly oriented spheroidal particles. Appl. Opt. 19, 962 (1980).CrossRefGoogle ScholarPubMed
10Selvarajan, A. and Srinivas, T.: Optical amplification and photosensitivity in sol-gel based waveguides. IEEE J. Quantum Electron. 37, 1117 (2001).CrossRefGoogle Scholar
11Orignac, X. and Almeida, R.M.: Silica-based sol-gel optical waveguides on silicon. IEE Proc. Optoelectron. 143, 287 (1996).CrossRefGoogle Scholar
12Lee, H.J., Hahn, S.H., Kim, E.J. and You, Y.Z.: Influence of calcinations temperature on structural and optical properties of TiO2–SiO2 thin films prepared by sol-gel dip coating. J. Mat. Sci. 39, 3683 (2004).CrossRefGoogle Scholar
13Jiwei, Z., Tao, Y., Liangying, Z. and Xi, Y.: The optical waveguiding properties of TiO2–SiO2 composite films prepared by the sol-gel process. Ceram. Int. 25, 667 (1999).CrossRefGoogle Scholar
14Kwon, C.H., Kim, J.H., Jung, I.S., Shin, H. and Yoon, K.H.: Preparation and characterization of TiO2–SiO2 nano-composite thin films. Ceram. Int. 29, 851 (2003).CrossRefGoogle Scholar
15Wallidge, G.W., Anderson, R., Mountjoy, G., Pickup, D.M., Gunawidjaja, P., Newport, R.J. and Smith, M.E.: Advanced physical characterization of the structural evolution of amorphous (TiO2)x(SiO2)1−x sol-gel materials. J. Mater. Sci. 39, 6743 (2004).CrossRefGoogle Scholar
16Portal, S. and Almeida, R.M.: Variable incidence infrared absorption spectroscopy of gel-derived silica and titania films. Phys. Status Solidi A 201, 2941 (2004).Google Scholar
17Chu, W.K., Mayer, J.W. and Nicolet, M.A.: Backscattering Spectrometry (Academic Press, New York, 1978), pp. 21–37.CrossRefGoogle Scholar
18Matsuda, A., Matsuno, Y., Tatsumisago, M. and Minami, T.: Changes in porosity and amounts of adsorbed water in sol-gel derived porous silica films with heat treatment. J. Sol-Gel Sci. Technol. 20, 129 (2001).CrossRefGoogle Scholar
19Barton, T.J., Bull, L.M., Klemperer, W.G., Loy, D.A., McEnaney, B., Misono, M., Monson, P.A., Pez, G., Scherer, G.W., Vartuli, J.C. and Yaghi, O.M.: Tailored porous materials. Chem. Mater. 11, 2633 (1999).CrossRefGoogle Scholar
20Yang, J., Ferreira, J.M.F., Weng, W. and Tang, Y.: Sol-gel preparation and electrorheological activity of SiO2–TiO2 composite powders. J. Colloid Interf. Sci. 195, 59 (1997).CrossRefGoogle ScholarPubMed
21 JCPDS-International Centre for Diffraction Data, PCPDFWIN, v. 1.30 (1997).Google Scholar
22Walters, J.K., Rigden, J.S., Dirken, P.J., Smith, M.E., Howells, W.S. and Newport, R.J.: An atomic-scale study of the role of titanium in TiO2:SiO2 sol-gel materials. Chem. Phys. Lett. 264, 539 (1997).CrossRefGoogle Scholar
23Whitten, J.L., Zhang, Y., Menon, M. and Lucovsky, G.: Electronic structure of SiO2: Charge redistribution contributions to the dynamic dipoles/effective charges of the infrared active normal modes. J. Vac. Sci. Technol. B 20, 1710 (2002).CrossRefGoogle Scholar
24Kamitsos, E.I.: Reply to comment on infrared-reflectance spectra of heat-treated, sol-gel-derived silica. Phys. Rev. B 53, 14659 (1996).CrossRefGoogle ScholarPubMed
25Song, C.F., Lü, M.K., Yang, P., Xu, D. and Tuan, D.R.: Structure and photoluminescence properties of sol-gel TiO2–SiO2 films. Thin Solid Films 413, 155 (2002).CrossRefGoogle Scholar
26Almeida, R.M., Guiton, T.A. and Pantano, C.G.: Characterization of silica gels by infrared reflection spectroscopy. J. Non-Cryst. Solids 121, 193 (1990).CrossRefGoogle Scholar
27Fang, Q., Meier, M., Yu, J.J., Wang, Z.M., Zhang, J-Y., Wu, J.X., Kenyon, A., Hoffmann, P. and Boyd, I.W.: FTIR and XPS investigation of Er-doped SiO2–TiO2 films. Mater. Sci. Eng. B 105, 209 (2003).CrossRefGoogle Scholar
28Borghesi, A., Pivac, B., Sassella, A. and Stella, A.: Oxygen precipitation in silicon. J. Appl. Phys. 77, 4169 (1995).CrossRefGoogle Scholar
29Larouche, S., Szymanowski, H., Klemberg-Sapieha, J.E., Martinu, L. and Gujrathi, S.C.: Microstructure of plasma-deposited SiO2/TiO2 optical films. J. Vac. Sci. Technol. A 22, 1200 (2004).CrossRefGoogle Scholar
30Wang, J., Brocklesby, W.S., Lincoln, J.R., Townsend, J.E. and Payne, D.N.: Local structures of rare-earth ions in glasses: The crystal-chemistry approach. J. Non-Cryst. Solids 163, 261 (1993).CrossRefGoogle Scholar
31Almeida, R.M., Vasconcelos, H.C., Gonçalves, M.C. and Santos, L.F.: XPS and NEXAFS studies of rare-earth doped amorphous sol-gel films. J. Non-Cryst. Solids 232–234, 65 (1998).CrossRefGoogle Scholar
32Orignac, X., Vasconcelos, H.C. and Almeida, R.M.: Structural study of SiO2–TiO2 sol-gel films by x-ray absorption and photoemission spectroscopies. J. Non-Cryst. Solids 217, 155 (1997).CrossRefGoogle Scholar
33Evans, D.L.: Solid solution of TiO2 in SiO2. J. Am. Ceram. Soc. 53, 418 (1970).CrossRefGoogle Scholar
34Aspnes, D.E.: Optical properties of thin films. Thin Solid Films 89, 249 (1982).CrossRefGoogle Scholar
35Mosaddeq-ur-Rahman, Md., Yu, G., Soga, T., Jimbo, T., Ebisu, H. and Umeno, M.: Refractive index and degree of inhomogeneity of nanocrystalline TiO2 thin films: Effects of substrate and annealing temperature. J. Appl. Phys. 88, 4634 (2000).CrossRefGoogle Scholar
36Benatsou, M., Capoen, B., Bouazaoui, M., Tchana, W. and Vilcot, J.P.: Preparation and characterization of sol-gel derived Er3+: Al2O3–SiO2 planar waveguides. Appl. Phys. Lett. 71, 428 (1997).CrossRefGoogle Scholar
37Chatterjee, S.: Light scattering by a dielectric films with periodically varying refractive index profiles. Phys. Scr. 67, 234 (2003).CrossRefGoogle Scholar
38Leskova, T.A., Maradudin, A.A. and Novikov, I.V.: Scattering of light from the random interface between two dielectric media with low contrast. J. Opt. Soc. Am. A 17, 1288 (2000).CrossRefGoogle ScholarPubMed