Optically written polymers used as optical interconnects and for hybridisation

The performance of a novel multifunctional acrylate based photo-polymer is presented. Rapid direct writing of multimode (50 µm square core) cladded waveguides, compliant bumps for flip-chip bonding and 45° total internal reflection mirrors for out of plane coupling have been realised using a high-power 325 nm He:Cd laser with high precision and repeatability. The losses are measured to be less than 0.17 dB/cm at 850 nm and less than 0.5 dB/cm at 1300 nm by cutback method. This custom multifunctional acrylate co-polymer has been found to be thermally stable up to a temperature of 300° as determined using DTA-TG analysis. © 2001 Elsevier Science B.V.