Dry etching of silver for the metallization in microelectronics is
investigated. Etching is performed using an electron-cyclotron-resonance
reactive-ion-beam-etching system (ECR-RIBE) in an Ar/CF4 or
Ar/CF4/O2 mixture. The etch characteristics are
strongly affected by ion energy (beam voltage and microwave energy); the
O2 concentration in the reactive mixture has only a small
effect. An anisotropic, smooth etch profile and clean surface are obtained.
Focused ion beam (FIB) and atomic force microscopy (AFM) have been used to
study the etched profile and the roughness, respectively.