All planar integration of high-Q, Er-doped silicon-rich silicon nitride microdisk with SU-8 waveguide for on-chip, Si-based light source

All-planar integration of a light source with coupling waveguide on a Si chip is achieved using high-Q, Er doped silicon-rich silicon nitride (SRSN) microdisks and SU-8 waveguide. As-fabricated microdisks show Q-factors of 1-1.5 times 10⁴ for both TE- and TM-like modes. Upon integration with single-mode SU-8 waveguide and clad with a polymer layer, Q-factor decreases to 5,000 for the TE-like mode, and 1,000 for TM-like mode. We obtain sharp Er³⁺ WGM emission coupled into the waveguide when the disk is pumped 1470 nm LD, indicating the promise of SRN:Er for compact, integrated Si- based light source.