| CPC H01J 37/32183 (2013.01) [H01H 1/46 (2013.01); H01J 37/32568 (2013.01); H01J 37/32715 (2013.01); H05H 1/01 (2021.05)] | 15 Claims |

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1. A plasma processing apparatus comprising:
a plasma processing chamber;
a substrate support disposed in the plasma processing chamber;
a first DC power source configured to generate a first DC voltage having a first voltage level;
a second DC power source configured to generate a second DC voltage having a second voltage level different from the first voltage level, the second DC voltage having a same polarity as a polarity of the first DC voltage;
a first switch configured to switch between a first conduction state and a first non-conduction state, the substrate support being connected to the first DC power source in the first conduction state and disconnected from the first DC power source in the first non-conduction state;
a second switch configured to switch between a second conduction state and a second non-conduction state, the substrate support being connected to the second DC power source in the second conduction state and disconnected from the second DC power source in the second non-conduction state;
a third switch configured to switch between a third conduction state and a third non-conduction state, the substrate support being connected to a reference potential in the third conduction state and disconnected from the reference potential in the third non-conduction state; and
a controller configured to cause:
the first conduction state of the first switch and the second non-conduction state of the second switch during a first period of a repeating sequence; and
the first non-conduction state of the first switch and the second conduction state of the second switch during a second period of the repeating sequence,
wherein the controller is configured to control the first switch, the second switch and the third switch to cause:
the first conduction state, the second non-conduction state and the third non-conduction state during the first period of the repeating sequence;
the first non-conduction state, the second conduction state and the third non-conduction state during the second period of the repeating sequence; and
the first non-conduction state, the second non-conduction state and the third conduction state during a third period of the repeating sequence between the first period and the second period.
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