High-Q short-wave mid-infrared silicon microring resonators based on foundry processes

Short-wave mid-infrared (SWMIR, 2.0–2.5 μm) photonics has diverse applications in free-space communications, LiDAR, and environmental monitoring. Silicon photonics with mature device fabrication processes and cost efficiency has emerged as a promising platform for SWMIR applications. Among various functional components, microring resonators stand out as essential elements for on-chip SWMIR systems due to their capability in wavelength filtering, sensing, and signal modulation. However, the large-scale fabrication of such devices, particularly those with high-quality-factors (Q-factors), remains a significant challenge. Here, we developed SWMIR high-Q silicon waveguide-integrated resonators based on a multi-project wafer (MPW) foundry service. Ridge and strip waveguides exhibit propagation losses of 1.22 and 1.37 dB/cm. Moreover, racetrack resonators were demonstrated with an intrinsic Q of ∼0.9 × 106 in the SWMIR waveband. The study presents a promising proof-of-concept demonstration of high-performance SWMIR silicon photonic devices using an MPW foundry process, highlighting the potential for scalable fabrication and providing a solid foundation for future application-specific integrated photonic systems.