Optimization of chalcogenides dry etching for near-and mid-IR photonic integrated waveguides development
Résumé
This paper presents the optimization of etching parameters of GeSbSebased chalcogenide glass (ChG) for near-and mid-infrared photonic applications. Single-mode Se4 on Se2 waveguides were fabricated via RF magnetron sputtering and patterned using reactive ion etching (RIE) and inductively coupled plasma (ICP) etching. Introducing argon into the CHF3-based etching chemistry significantly improved waveguide sidewall morphology, reducing propagation losses from 7.5 dB/cm to 2.6 ± 0,6 dB/cm at 1.55 µm. In the mid-infrared, losses were lowered to 1.45 ± 0.81 dB/cm at 4.11 µm. Through waveguide sidewall roughness extraction from SEM imaging, these experimental losses were simulated, with a very good agreement, as a function of etching parameters, using the Payne-Lacey. These findings contribute to developing low-loss chalcogenide-based photonic devices.