Fabrication of optical microresonators using proton beam writing

ABSTRACT Proton beam writing is a high-resolution direct write lithographic technique capable of producing three dimensional, high aspect ratio structures with smooth and vertical sidewalls. In this work, the fabrication of high quality SU-8 optical microdisk resonator with a Q factor of 104 is demonstrated. Simulations carried out using finite difference time domain (FDTD) are in good agreement with experimental results. By introducing rhodamine B laser dye into a SU-8 resist spiral microdisk cavity lasing was achieved with threshold pump fluence of 127 μJ/mm2 when pumped with a 532 nm pulsed Nd:YAG laser.