Abstract

We achieved facile surface relief (SR) formation with symmetrical and asymmetrical structure in photoreactive polymer/benzophenone (BP) monomer composite films by holographic exposure to 325-nm He–Cd laser beams. Under holographic exposure, photo-excited BP molecules induced photo-crosslinking of the composite film, incorporating BP molecules into the polymer and generating molecular motion, resulting in SR formation. The height of the SR depended on the polymer/BP ratio, and reached 550 nm. Furthermore, slantwise exposure resulted in asymmetrical SR formation. The resultant SR gratings were transparent to visible light and thermally stable up to 95 °C.