All polymer process compatible optical polymer material

Abstract

A terploymer containing N-halogenated phenyl maleimide units or N-halogenated phenyl bismaleimide units, one or more second units selected from the group consisting of halogenated acrylates, halogenated styrenes, halogenated vinyl ethers, halogenated olefins, halogenated vinyl isocyanates, halogenated N-vinyl amides, halogenated allyls, halogenated propenyl ethers, halogenated methacrylates, halogenated maleates, halogenated itaconates, and halogenated crotonates and one or more third units comprising a monomer containing both a free radically polymerizable group and cationic ring opening polymerizable group, is prepared by radical co-polymerization. The resulting linear plastic polymer group contains a UV, or e-beam curable ring opening polymerizable functional groups. Such plastic polymer is then blended with cationic photoiniator and processed into optical waveguide structures using a hot embossing technique. The terpolymer is subsequently crosslinked by exposure to UV or E-beam radiation and thermal post-bake. Alternatively, in a direct contact photolithographic process, the terpolymer is mixed with cationic photoinitiator, and deposited or coated onto a substrate. Then optical waveguide structures are formed by exposing the terpolymer to UV or E-beam radiation through a photomask. After thermal postbake, the exposed area of the photopolymer is chemically crosslinked. The unexposed area is washed away with solvent. The terpolymer is fully compatible with polymer processes such as micromolding, hot-embossing, coating and direct contact photolithography processes to fabricate polymer waveguide devices. The crosslinked polymer waveguides have low optical loss, good thermal and environmental stability and low coefficient of thermal expansion.