Silica (SiO2) optical waveguides have been fabricated on the surface of silicone [(SiO(CH3)2)n] rubber by photochemical modification of silicone rubber into silica with 157 nmF2-laser radiation. The 2 mm thick silicone was exposed through a thin (∼0.2 mm) air layer to generate oxygen radicals that chemically assisted in the silica transformation. Silica waveguides were defined in 8-16 µm wide exposure strips by a proximity Cr-on-CaF2 photomask. Optimum laser processing conditions are presented for generating crack-free waveguides with good optical transparency at red (635 nm) and infrared (1550 nm) wavelengths. A propagation loss of ∼6 dB/cm is reported at the 1550 nm wavelength.
© 2005 Optical Society of America
(160.5470) Materials : Polymers
(160.6030) Materials : Silica
(220.4610) Optical design and fabrication : Optical fabrication
(230.7370) Optical devices : Waveguides
(240.6670) Optics at surfaces : Surface photochemistry
Masayuki Okoshi, Jianzhao Li, and Peter R. Herman, "157 nm F2-laser writing of silica optical waveguides in silicone rubber," Opt. Lett. 30, 2730-2732 (2005)