Fabrication And Properties Of Azo Polymer EO Modulators

Recent years have witnessed significant progress in the syntheses of second-order nonlinear optical （NLO） polymers. The application of NLO polymers in electro-optic （EO） modulators is one of most important areas for the current investigations. This thesis is dedicated to the fabrication of EO modulators with NLO azo polymers and study of their performance as optoelectronic devices.Properties of epoxy-based polymer BP-AN and azo polymer BP-AZ-NT were characterized for the design and fabrication of the EO modulators. Based on the data, we completed and optimized the design of the high speed traveling-wave polymer EO intensity modulators with 40 GHz bandwidth and half-wave voltages below 5 V, polymer electric field sensors, and RF phase shifters.Some key problems encountered in the fabrication were studied and solved, which included the selection of proper cross-linker, preparation of cladding film with smooth surface, avoiding film damage in RIE process among others. MSL traveling-wave electrode polymer EO modulators were fabricated by using NLO azo polymer BP-AZ-NT. The half-wave voltage was detected to be 32.1 V and the microwave transmission loss coefficient was 0.6 dB/cm·cm^1/2. Polymer electric field sensors and RF phase shifters were fabricated. The half-wave voltage tested in the RF phase shifter was 81.8 V, corresponding to the EO coefficient of 3.27 pm/V of the core layer.Photo bleaching method was used to prepare polymer waveguides, which had the optical propagation loss of 13.05 dB/cm.