O/E Integration of Polymer Waveguide Devices by Using Replication Technology

The simple optoelectronic integration of polymer-based optical waveguide devices and the development of the realization processes have been critical issues for cost-effective, high-volume manufacturing of a next-generation optoelectronic integrated circuit (OEIC). We demonstrated the replication technology as a means of implementing the polymer microoptoelectromechanical system (MOEMS)-based packaging structure providing the optical/electrical (O/E) integration of the functional polymer waveguide device. To achieve this, a micromechanical packaging structure consisting of an electric-circuit-embedded polymer optical bench and planar-lightwave-circuit (PLC)-type waveguide chip with alignment microstructure was designed, and the realization process incorporating the UV imprint technique was investigated. To improve optical coupling efficiency, the electric circuit was embedded under the optical bench and the contact pads were opened at the bottom of the alignment pits. In addition, a conductive adhesive-fill space was created at the alignment pits to accommodate the surplus conductive adhesive. Efficient fiber-chip coupling and good electrical contact of upside-down mounted single-mode waveguide chip was accomplished by the simple joining of the electric-circuit patterned micropedestals on the waveguide chip and the alignment pits on the bench. A coupling loss of 0.9 dB per coupling face was measured with a single-mode fiber at a wavelength of 1.5 mum. It was concluded that the replication technology has versatile application capabilities in manufacturing next generation optical interconnect systems