Reactive Ion Etching of Si Using Ar/F2 Plasma

We investigated the Si dry etching process using Ar/F 2 plasma. A vertical etching profile and a smooth etched surface, which satisfy the requirements for optical device fabrication, were obtained. The etching rate of Si was approximately 0.1 \mbox{$\mu$m}/min at 5 Pa and 150 W. We believe that Ar/F 2 plasma etching is a very simple and useful process for fabricating Si-based optical devices, such as photonic crystals, narrow optical waveguides, and micro-electro-mechanical systems (MEMS). In addition, this etching process is suitable for the protection of the earth environment, because the global warming potential (GWP) of F is 0.