Dry Etching to form Submicron Features in CMR Oxides: (Pr,Ba,Ca)MnO₃ and (La,Sr)MnO₃

Abstract

Effective pattern transfer into (Pr,Ba,Ca)MnO3 and (La,Sr)MnO3 has been achieved using Cl2/Ar discharges operated under Inductively Coupled Plasma conditions. Etch rates up to 900 Å-min−1 for (La,Sr)MnO3 and 300 Å-min−1 for (Pr,Ba,Ca)MnO3 were obtained, with these rates being a strong function of ion flux, ion energy and ion-to-neutral ratio. The etching is still physically-dominated under all conditions, leading to significant surface smoothing on initially rough samples. Sub-micron (0.35 μm) features have been produced in both materials using SiNx as the mask.