Etching characteristics and mechanisms of the MgO thin films in the CF4/Ar inductively coupled plasma

The etching characteristics and mechanisms of MgO thin films in CF4/Ar inductively coupled plasma were investigated. It was found that the changes in gas mixing ratio as well as in gas pressure result in a non-monotonic behavior of the MgO etch rate. Plasma diagnostics by Langmuir probe indicated the noticeable sensitivity of both electron temperature and density to the variations of the processing parameters. The combination of 0-dimensional plasma model with the model of surface kinetics showed that the reason of the non-monotonic etch rate is connected with the concurrence of physical and chemical pathways in ion-assisted chemical reaction.