Reactive ion etching of Pt thin films for fabrication of microcapacitor

Abstract

The reactive ion etching (RIE) of Pt thin film was carried out in CCl2F2/Ar plasma to investigate etching mechanism of Pt thin film. Etch rate depends strongly on the composition variation of CCl2F2 and Ar plasma. A kind of synergistic effect was found in Pt dry etching: chemically enhanced physical etching or physically enhanced chemical etching. It frequently occurs in RIE of other materials such as oxides and nitrides. Therefore the profile, etch rate and selectivity could be controlled by gas composition. We fabricated Pt storage node for Gbit scale DRAM successfully.