スピンコート法によるメソ構造を有する透明シリカ薄膜の作製と評価

概要

論文の詳細を見る
Transparent mesoporous silica thin films were successfully fabricated via spin coating method using precursor solutions of water/tetraethyl orthosilicate (TEOS) system with cetyltrimethylammonium bromide (CTAB) and nitric acid catalysis. The optimum conditions for the fabrication of films were as follows: 1) The molar ratios of precursor solution were TEOS/CTAB/H_2O = 3-9.5/1/185 in the pH range 2-3 adjusted by nitric acid. The precursor solution became transparent after aging for 2-3 h, and transparent thin films were obtained by spinning at 1000-5000 rpm. 2) The thickness of transparent thin films obtained by a single spincoating was 0.5-1.2 μm. The transmittance to visible light and the refractive index of thin films were measured to be 97% and 1.44, while Vickers hardness and Young's modulus were 0.706 GPa and 32.2 GPa, respectively. The transparency of thin films was unchanged after drying at 373 K or firing at 723 K. 3) The characteristic diffraction peak of mesoporous structure at 2θ=2-3°in X-ray diffraction (XRD) diagrams was observed for all transparent thin films. The crystal phase of these films varied from lamella, hexagonal to cubic when compositions of TEOS/CTAB in precursor solutions were increased from 3-7, 7.5-8 to 9-9.5.
社団法人日本セラミックス協会の論文
2003-06-01