Dry etching of NiFe∕Co and NiFe∕Al–O∕Co multilayers in an inductively coupled plasma of Cl2∕Ar mixture

Dry etching of NiFe∕Co and NiFe∕Al–O∕Co multilayers was carried out in inductively coupled Cl2∕Ar plasmas. An ion-enhanced etch mechanism took a critical role for desorption of chlorine etch products. NiFe∕Al–O∕Co showed a faster etch rate than NiFe∕Co at various etch conditions. Anisotropic and smooth features were obtained using a photoresist mask. Sidewall contamination with etch products was observed at a higher Cl2 concentration (>50%). Postetch cleaning of the etched samples in deionized water reduced the chlorine residues substantially.