Rapid direct writing of high-aspect ratio trenches in silicon: Process physics

Abstract

The processes governing direct-write etching of semiconductors with halogen gases are studied by concentrating on a specific materials system: the etching of silicon using the output from an argon-ion laser and chlorine gas to form high-aspect ratio trenches. Specifically, the effects of laser power, laser polarization, laser scan velocity, Cl2-gas pressure, and the addition of buffer gases on the trench formation process have been studied. A simple model has been developed which relates trench depth and these parameters. Model results are presented and compared with experimental data.