Dry etching of SiC using Ar/F2 plasma and XeF2 plasma

Abstract

We investigated the SiC dry etching process using Ar/F2 plasma and XeF2 plasma. We carried out optical observation of Ar/F2 plasma and XeF2 plasma. The dominant etching species were different between Ar/F2 plasma and XeF2 plasma. The etching rates of SiC were approximately 100 nm/min at 25 sccm and 200 W for Ar/F2 plasma and 45 nm/min at 2.5 sccm and 100 W for XeF2 plasma. Vertical etching profiles and a smooth etched surface were obtained. The average roughness of the etched bottom surface was 1 nm, which satisfied the requirements for optical device fabrication. We believe that the proposed etching process using F2 of zero-global-warming-potential gases is very simple and useful for fabricating optical devices and micro-electromechanical systems (MEMSs).