Plasma processing apparatus

A plasma processing apparatus comprising:

• a plasma processing chamber;
• a substrate support disposed in the plasma processing chamber, the substrate support including a base, an electrostatic chuck and an edge ring, the electrostatic chuck being disposed on the base and having a substrate support surface and a ring support surface, and the edge ring being disposed on the ring support surface to surround a substrate disposed on the substrate support surface;
• a substrate chuck electrode disposed below the substrate support surface in the electrostatic chuck;
• at least one ring chuck electrode disposed below the ring support surface in the electrostatic chuck;
• a first bias electrode disposed in the electrostatic chuck and having a first outer diameter;
• a second bias electrode disposed in the electrostatic chuck and having a second outer diameter greater than the first outer diameter;
• a third bias electrode disposed in the electrostatic chuck and having a third outer diameter greater than the second outer diameter;
• a first DC power supply configured to generate a first primary DC signal having a first primary voltage level;
• a second DC power supply configured to generate a second primary DC signal having a second primary voltage level;
• a third DC power supply configured to generate a third primary DC signal having a third primary voltage level;
• a voltage adder configured to generate first to third secondary DC signals from the first to third primary DC signals, the first secondary DC signal having a first secondary voltage level, the second secondary DC signal having a second secondary voltage level, the third secondary DC signal having a third secondary voltage level, wherein the first secondary voltage level, the second secondary voltage level and the third secondary voltage level are selected not to overlap one another from
• the first primary voltage level,
• a voltage level derived by adding the first primary voltage level and the second primary voltage level, and
• a voltage level derived by adding the first primary voltage level and the third primary voltage level;
• a first voltage pulse generator electrically connected to the first bias electrode and configured to generate a first voltage pulse signal from the first secondary DC signal, the first voltage pulse signal having the first secondary voltage level;
• a second voltage pulse generator electrically connected to the second bias electrode and configured to generate a second voltage pulse signal from the second secondary DC signal, the second voltage pulse signal having the second secondary voltage level;
• and
• a third voltage pulse generator electrically connected to the third bias electrode and configured to generate a third voltage pulse signal from the third secondary DC signal, the third voltage pulse signal having the third secondary voltage level.