Fabrication of a high-Q factor ring resonator using LSCVD deposited Si₃N₄ film

High-quality silicon nitride (Si₃N₄) films with a low stress and optical loss weredeposited at low temperature (150°C) using liquid source chemical vapor deposition(LSCVD). The refractive index of the Si₃N₄ film was optimized by changing the compositionratio and deposition temperature. An integrated photonic structure of micro-ring resonatorbased on the as-deposited Si₃N₄ layer has been demonstrated to exemplify its viability as aphotonic integration platform. Bragg gratings are fabricated at both ends of the buswaveguide to improve coupling efficiency and testing flexibility. A measured waveguide lossof 2.9 dB/cm and a high Q-factor of 5.2 × 10⁴ are achieved. The LSCVD deposited Si₃N₄ istherefore a highly promising photonic integration platform for various integrated photonicapplications.