Fabrication and characterization of on-chip silicon spherical-like microcavities with high Q-factors

An effective way to fabricate high-quality ( Q) silicon microcavities on-chip is proposed and studied. Our fabrication technique consists of two significant steps: (1) patterning a special silicon micro-pillar by Bosch processes and (2) subsequent reflow of the pillar into a spherical-like microcavity using a laser pulse at 532 nm. Its shape and surface roughness are characterized using a scanning electron microscope and an atomic force microscope. The root-mean-square roughness of the surface is about 0.6 nm. A representative value for the loaded Q- factors of our silicon spherical-like microcavities is on the order of 10(5).