Plasma Characterization in Chlorine-Based Reactive Ion Beam Etching and Chemically Assisted Ion Beam Etching

We measured the chlorine plasma characteristics in reactive ion beam etching (RIBE) and chemically assisted ion beam etching (CAIBE) process. In the CAIBE process, the energy peak of Cl + ionized by Ar + appears in the energy range of 50–70 eV and this Cl + energy peak increases with an increase of Ar + energy. We observed that the excited state Cl 2 density in CAIBE is lower than that in RIBE as measured by appearance mass spectrometry (AMS).