Plasma processing apparatus and plasma processing method

A plasma processing apparatus comprising:

• a chamber;
• a substrate support having a lower electrode and provided in the chamber;
• a plasma generator configured to generate plasma from a gas in the chamber;
• a first power source configured to generate an electric bias and electrically connected to the lower electrode;
• and
• a second power source configured to apply a positive voltage to a member that is exposed to the plasma generated in the chamber,
• wherein the second power source is configured to apply the positive voltage to the member in a first period that is a part of a whole period in which the electric bias that is output from the first power source to the lower electrode has a potential equal to or higher than an average potential of the electric bias within a cycle thereof, and
• the first power source is configured to output the electric bias having a positive potential to the lower electrode in a second period after the first period.