摘要
Femtosecond pulsed lasers offer significant advantages for micro-/nano-modifications in integrated photonics.Microring resonators(MRRs),which are essential components in photonic integrated circuits(PICs),are widely employed in various fields,including optical communication,sensing,and filtering.In this study,we investigate the modification mechanisms associated with femtosecond laser interactions with MRRs fabricated on a lowpressure chemical vapor deposition(LPCVD)-silicon nitride(SiN)photonic platform,with emphasis on the post-fabrication trimming of second-order microring filters and MRR-based four-channel wavelength-division multiplexing(WDM).We examine 10 MRRs located at different positions on a wafer and discovered resonance wavelength shifts exceeding 1 nm due to fabrication-induced variations.Interactions between femtosecond lasers and LPCVD-SiN films resulted in silicon nanoclusters,which significantly redshifted the resonance wavelength of the MRRs.Additionally,the extinction ratio of MRRs improved by over 11.8 dB within the conventional band after laser modification.This technique is employed to enhance the performance of second-order MRRs and the four-channel WDM configuration,thus providing critical experimental evidence for leveraging femtosecond lasers to optimize LPCVD-SiN PICs.
基金
National Natural Science Foundation of China(62375274)
Key Deployment Project of Chinese Academy of Sciences(KGFZD-145-24-12)
Shanghai Industrial Collaborative Innovation Project(XTCX-KJ-2023-01)。
