Etch end-point detection of GaN-based devices using optical emission spectroscopy

In this study, optical emission spectroscopy (OES) was performed to detect etch end-point during the etching of GaN/AlGaN-based devices. In-situ OES experiments during the etching were carried out to measure the etch product signals of AlGaN/GaN heterostructures as well as single III-nitrides. A possibility of detecting etch end-point by OES was identified for both optoelectronic devices and electronic devices using etch product emissions such as Al (396.1 nm) and Ga (417.2 nm).