RF-plasma assisted fast atom beam etching

Etching technique with a high selectivity, low damage and high anisotropy has been studied widely to satisfy the requirement for advanced semiconductor devices. It is effective to use neutral atoms as an etching species to prevent various anomaly originated in built-in charge due to ions as it is progressed for further miniaturization and precise dimension control. Also it is necessary to decrease the kinetic energy of the etching species to prevent damage on the etched surface. The low energy etching with neutral species should be necessary to satisfy the above requirement. Although some techniques that use neutral species have been reported, Fast Atom Etching (FAB) is given as one of the technologies. The characteristics are the high neutralization rate and the highly collimation of the atom beam. To sustain the discharge in the source, normally high DC voltage above 1 kV is necessary. In this study we propose RF-assisted-FAB that make it possible to work at a relatively low energy. We report the preliminary results.