Cl₂-based inductively coupled plasma etching of CoFeB, CoSm, CoZr and FeMn

Abstract

Thin films of CoFeB, CoSm, CoZr and FeMn have been etched in inductively coupled plasma Cl2 discharges with He, Ar or Xe as the inert gas additive as an additional physical component to the etch process. The etch rates decrease with pressure and go through maxima with rf chuck power and discharge composition. There is a transition from net deposition to etching with increasing source power and rf chuck power, consistent with the need to provide sufficient ion energy and ion/neutral flux ratio to achieve efficient etching of magnetic materials.