Hybrid sol-gel channel waveguide patterning using photoinitiator-free materials

Fabrication of organic-inorganic sol-gel glass channel waveguides by ultraviolet (UV) photopolymerization of material synthesized from the precursor methacryloxypropyltrimethoxysilane is performed using a pulsed 248-nm excimer laser without the need of photoinitiators. The transmission spectra of channel waveguides are presented. Absorption bands are identified, revealing high loss (4-5 dB/cm) at 1.55 mum mainly due to strong OH group content and an acceptable value of 0.4 dB/cm at 1.3 mum. Heat treatment and UV irradiation showed similar effects on the transmission spectra of channel waveguides, revealing no loss improvement in the 1.55-mum region.