Exploration of lift-off Ge–As–Se chalcogenide waveguides with thermal reflow process

Abstract Ge11.5As24Se64.5 chalcogenide waveguides were fabricated using lift-off method and thermal reflow process. The morphologies of the waveguide were characterized, and the geometry modification after thermal reflow was analyzed. The thermal reflow process can effectively improve the surface quality and reduce optical loss of the waveguides. Up to 36% sidewall roughness and 37% optical loss reduction were achieved after the waveguides reflowed at 310 °C, and the possible factors of high optical loss for reflow at higher temperature were discussed. All the results indicate that the thermal reflow process could be a feasible choice for low-loss integrated chalcogenide photonics application.