Fiber to polymer-waveguide coupling with low insertion loss

Abstract

Low-loss coupling of optical fiber to a polymer waveguide was demonstrated using a V-groove on a silicon substrate. The waveguide was fabricated directly on the silicon substrate using a direct writing technique. The fiber was mounted in a V-groove on a SiO2-coated silicon substrate, and then the azo polymer was coated onto the substrate and cured at 200 °C. Finally a waveguide was ‘written’ precisely aligned with the fiber’s output tip. The insertion loss was measured to be about 1.1 dB.