title: Permanent fine tuning of silicon microring devices by femtosecond laser surface amorphization and ablation.
abstract: We demonstrate the fine tuning capability of femtosecond laser surface modification as a permanent trimming mechanism for silicon photonic components. Silicon microring resonators with a 15 µm radius were irradiated with single 400 nm wavelength laser pulses at varying fluences. Below the laser ablation threshold, surface amorphization of the crystalline silicon waveguides yielded a tuning rate of 20 ± 2 nm/J · cm(-2)with a minimum resonance wavelength shift of 0.10nm. Above that threshold, ablation yielded a minimum resonance shift of -1.7 nm. There was some increase in waveguide loss for both trimming mechanisms. We also demonstrated the application of the method by using it to permanently correct the resonance mismatch of a second-order microring filter.
authors.affiliation: Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta T6G 2V4, Canada. bachman@ualberta.ca
authors.forename: Daniel
authors.initials: D
authors.lastname: Bachman
authors.forename: Zhijiang
authors.initials: Z
authors.lastname: Chen
authors.forename: Robert
authors.initials: R
authors.lastname: Fedosejevs
authors.forename: Ying Y
authors.initials: YY
authors.lastname: Tsui
authors.forename: Vien
authors.initials: V
authors.lastname: Van
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D007834:Lasers; D012825:Silicon / Q000737:chemistry* / Q000528:radiation effects*; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D013499:Surface Properties / Q000528:radiation effects
chemical_list: D012825:Silicon