High quality factor silicon oxynitride optical waveguide ring resonators

Abstract In this manuscript, we report the design, manufacturing and characterization of silicon oxynitride (SiON) based optical waveguide ring resonators (OWRR) which achieve higher quality factors with respect to the state-of-the-art waveguide ring resonators. To improve the coupling efficiency, Bragg grating couplers are used at both ends of the designed resonators instead of the conventional directional couplers. In the proposed design, the core of OWRR structure was realized in the optimized refractive silicon oxynitride films deposited by liquid source chemical vapor deposition (LSCVD), under controllable composition ratio, time slot duration, and deposition temperature. The SiON based resonators have achieved a measured waveguide loss of 4.07 dB/cm and a quality factor of 0.93 × 105 in the transverse electric (TE) mode, and this by the way outperforms the results fulfilled with the state-of-the-art waveguide ring resonators.