Fabrication and characterization of high quality GeSbSe reflowed and etched ring resonators
Michael Grayson, Bo Xu, Thariq Shanavas, M. Zohrabi, Kyuyoung Bae, Juliet T. Gopinath, Wounjhang Park
Abstract
We demonstrate the fabrication of high Q Ge 28 Sb 12 Se 60 ring resonators in an all chalcogenide platform through electron-beam lithography, lift-off and thermal reflow. We achieve a Q factor of (3.9 ± 0.2) × 10 5 in the reflowed ring resonators and (2.5 ± 0.2) × 10 5 in the reactive ion etched ring resonators at 1550 nm. We measure the line roughness of these devices to estimate the scattering loss. We determine the material and scattering losses of the waveguide and find an additional 1.1 dB/cm excess loss from surface absorption. We fabricate Ge 23 Sb 7 S 70 waveguides with 0.6 dB/cm of losses and show that Ge 23 Sb 7 S 70 waveguides do not experience the same kind of excess loss when fabricated under the same conditions. This indicates the excess loss is related to the chemical composition of Ge 28 Sb 12 Se 60 compound.