Investigation of Q degradation in low-loss SiN from heterogeneous laser integration.

High-performance, high-volume-manufacturing SiN photonics requires extremely low waveguide losses augmented with heterogeneously integrated lasers for applications beyond traditional markets of high-capacity interconnects. State-of-the-art quality factors (Q) over 200 million at 1550 nm have been shown previously; however, maintaining high Qs throughout laser fabrication has not been shown. Here, SiN resonator intrinsic Qs over 100 million are demonstrated on a fully integrated heterogeneous laser platform. Q is measured throughout laser processing steps, showing degradation down to 50 million from dry etching, metal evaporation, and ion implant steps, and controllable recovery to over 100 million from annealing at 250 C-350 C.