Titania/Ormosils Organic-Inorganic Hybrid Thin Films Doped with Azobenzene Small Molecules for Optical Switch Applications

Abstract

Titania/organically modified silanes (ormosils) organic-inorganic hybrid thin films doped with azobenzene small molecules are prepared by a low temperature sol-gel spin-coating process for optical switch applications. Acid-catalyzed solutions of γ-glycidoxypropyltrimethoxysilane and methyltrimethoxysilane mixed with tetrapropyl orthotitanate are used as matrix precursors. Atomic force microscopy is used to study the morphological properties of the hybrid thin films. Results indicate that crack-free thin films with a thickness of about 1.3μm can be obtained by a single spin-coating process after a low heat treatment temperature. The propagation mode properties of the hybrid thin films are also studied by employing a prism coupling technique. The photo-responsive properties of the hybrid films baked at different temperatures are induced by an irradiation with UV light and subsequent visible light.