A Novel Buckle‐Free Large Rib Microdisk with Submicrometer Thickness

Thin large microdisks, that are key to dense spectral microcomb generation at visible‐to‐UV wavelengths, face challenges in fabrication. One of the most difficult issues is the buckling effect that makes comb generation infeasible due to the severe degradation of cavity optical quality factor. Herein, a novel rib disk structure that significantly mitigates the buckling effects is introduced. Using this approach, millimeter‐sized buckle‐free microdisks with sub‐micrometer thickness and high optical quality factor exceeding 107 are obtained.