Abstract
Porous silica films were obtained by a heat treatment of poly(ethyleneglycol)-containing gels for micro-patterning. Changes in porosity and the amount of adsorbed water with the heat treatment temperature in the silica films were evaluated from the refractive index of the films. The apparent refractive index of the silica films in an ambient atmosphere was much higher than the intrinsic refractive index of the film due to the large amount of adsorbed water in the films. The amount of adsorbed water in the films decreased with an increase in the heat treatment temperature and became almost zero after a heat treatment at 850°C. The decrease in the amount of adsorbed water in the films was caused by the decrease in silanol groups, which acted as the sites for water adsorption in the films. The drastic decreases in thickness and in porosity of the films at temperatures from 850 to 950°C occurred after the disappearance of silanol groups in the films. The densification of the films due to collapse of the pores at high temperatures should have resulted from the viscous flow of silica network.
Similar content being viewed by others
References
Y. Xia, J.A. Rogers, K.E. Paul, and G.M. Whitesides, Chem. Rev. 99, 1823 (1999).
H. Schmidt, J. Sol-Gel Sci. and Tech. 1, 217 (1994).
R. Danzebrink and M.A. Aegerter, Thin Solid Films 351, 115 (1999).
N. Tohge, A. Matsuda, T. Minami, Y. Matsuno, S. Katayama, and Y. Ikeda, J. Non-Cryst. Solids 100, 501 (1988).
A. Matsuda, Y. Matsuno, M. Tatsumisago, and T. Minami, J. Am. Ceram. Soc. 81, 2849 (1998).
M. Mennig, A. Gier, H. Krug, and H. Schmidt, SPIE 3136, 480 (1997).
A. Matsuda, Y. Matsuno, S. Katayama, T. Tsuno, N. Tohge, and T. Minami, SPIE 1328, 62 (1990).
Y. Mitsuhashi, A. Matsuda, and Y. Matsuno, SPIE 1758, 105 (1992).
A. Matsuda, Y. Matsuno, Y. Mitsuhashi, N. Tohge, and T. Minami, Key Engineering Materials 150, 111 (1998).
A. Matsuda, T. Kogure, Y. Matsuno, S. Katayama, T. Tsuno, N. Tohge, and T. Minami, J. Am. Ceram. Soc. 76, 2899 (1993).
A. Matsuda, Y. Matsuno, S. Katayama, T. Tsuno, N. Tohge, and T. Minami, J. Ceram. Soc. Japan 102, 330 (1994).
B.E. Yoldas, Appl. Opt. 19, 1425 (1980).
W.A. Pliskin and P.P. Castrucci, Electrochem. Technol. 6, 85 (1968).
K.H. Guenther, Appl. Opt. 23, 3612 (1984).
K. Kinoshita and M. Nishibori, J. Vac. Sci. Technol. 6, 730 (1969).
M. Nogami and Y. Moriya, J. Non-Cryst. Solids 37, 191 (1980).
K. Kamiya, S. Sakka, and M. Mizutani, J. Ceram. Soc. Japan 86, 552 (1978).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Matsuda, A., Matsuno, Y., Tatsumisago, M. et al. Changes in Porosity and Amounts of Adsorbed Water in Sol-Gel Derived Porous Silica Films with Heat Treatment. Journal of Sol-Gel Science and Technology 20, 129–134 (2001). https://doi.org/10.1023/A:1008788004762
Issue Date:
DOI: https://doi.org/10.1023/A:1008788004762