High-Q silica microdisk optical resonators with large wedge angles on a silicon chip

Abstract

We experimentally demonstrate high optical quality factor silica microdisk resonators on a silicon chip with large wedge angles by reactive ion etching. For 2-μm-thick microresonators, we have achieved wedge angles of 59°, 63°, 70°, and 79° with optical quality factors of 2.4×107, 8.1×106, 5.9×106, and 7.4×106, respectively, from ∼80 μm-diameter microresonators in the 1550 nm wavelength band. Also, for 1-μm-thick microresonators, we have obtained an optical quality factor of 7.3×106 with a wedge angle of 74°.