Plasma processing method and plasma processing apparatus
A plasma processing apparatus for generating a plasma in a plasma processing space in a processing chamber and plasma-processing a target object includes a plasma-exciting high frequency power supply for applying a plasma-exciting high frequency power. Further, the plasma processing apparatus includes at least one of a potential-controlling high frequency power supply for applying a potential-controlling high frequency power having a frequency lower than that of the plasma-exciting high frequency power and a DC power supply for applying a DC voltage; and a mounting table for mounting thereon a target object. Furthermore, the plasma processing apparatus includes an auxiliary electrode, provided at a position outer side of the target object mounted on the mounting table while facing the mounting table, connected to at least one of the potential-controlling high frequency power supply and the DC power supply.
1. A plasma processing apparatus for generating a plasma in a plasma processing space in a processing chamber and plasma-processing a target object, the plasma processing apparatus comprising:
a plasma-exciting high frequency power supply for applying a plasma-exciting high frequency power;
a potential-controlling high frequency power supply for applying a potential-controlling high frequency power having a frequency lower than that of the plasma-exciting high frequency power;
a DC power supply for applying a DC voltage;
a mounting table for mounting thereon the target object; and
an auxiliary electrode provided at a position outer side of the target object mounted on the mounting table while facing the mounting table, the auxiliary electrode being connected to the potential-controlling high frequency power supply and the DC power supply,
wherein the auxiliary electrode is arranged around an outer periphery of an upper electrode to be separated from the upper electrode,
wherein application of a high frequency power from the potential-controlling high frequency power supply to the auxiliary electrode and application of a DC voltage from the DC power supply to the auxiliary electrode are switched, and
wherein the plasma processing apparatus further comprises a switching mechanism for switching an apply destination of a high frequency power from the potential-controlling high frequency power supply and a DC voltage from the DC power supply between the auxiliary electrode and the upper electrode.
2. The plasma processing apparatus of claim 1 , wherein a high frequency power applied from the plasma-exciting high frequency power supply is set to be higher than or equal to about 200 W.
3. The plasma processing apparatus of claim 1 , wherein when a plurality of different etching processes is consecutively performed on a multilayer structure in the processing chamber, application of a high frequency power from the potential-controlling high frequency power supply to the auxiliary electrode and application of a DC voltage from the DC power supply to the auxiliary electrode are switched in accordance with each etching process condition.
4. The plasma processing apparatus of claim 1 , wherein the switching mechanism, switches the apply destination when a plurality of different etching processes are consecutively performed on a multilayer structure in the processing chamber.
5. The plasma processing apparatus of claim 1 , wherein the auxiliary electrode is made of metal or a material including silicon.
6. The plasma processing apparatus of claim 1 , wherein a wall of the processing chamber includes a member obtained by thermally spraying an insulating material on an aluminum base, or a member obtained by coating silicon carbide on a silicon or an aluminum base.