High-quality LiNbO_3 microdisk resonators by undercut etching and surface tension reshaping

We report ultra-smooth LiNbO(3) microdisk resonators fabricated by selective ion implantation, chemical etching, and thermal treatment. The undercut microdisk structure is produced by chemically etching the buried lattice damage layer formed by selective ion implantation. By thermal treatment, surface tension smoothes and reshapes microdisk surface topography. The resonant characteristics of microdisk resonators are simulated by finite element method and are well consistent with the experimental results. The 20μm-diameter microdisk resonator has the FSR of 16.43nm and the Q factor of 2.60 × 10(4). The produced LiNbO(3) microdisk resonators can be utilized in new microdisk applications with electro-optic and nonlinear-optic effects.