Free-carrier effects in polycrystalline silicon-on-insulator photonic devices

Photonic systems integrated into microelectronic systems using the well established integrated chips fabrication technologies offer immense opportunity in overcoming the bandwidth and power limitations IC faces. The use of deposited polycrystalline silicon in the fabrication of photonic devices has the potential of offering monolithic integration, promising electrical and optical properties, under optimized micro-fabrication, and lower costs. In this thesis, the design, fabrication and optical testing of waveguide devices on polycrystalline silicon platform is presented. Single mode polysilicon waveguide devices were fabricated at the RIT SMFL. The polysilicon waveguides fabricated successfully coupled and guided light. The transmission was measured over several lengths and the cut back method was used to quantify the free carrier absorption and propagation losses of polysilicon at 1550 nm wavelength. Comparisons were made with data for crystalline silicon. The absorption coefficient for polysilicon was found to be 25.9% higher than that of crystalline silicon