A plasma processing apparatus includes a process container that forms a process space to accommodate a target substrate, and a first electrode and a second electrode disposed opposite each other inside the process container. The first electrode is an upper electrode and the second electrode is a lower electrode and configured to support the target substrate through a mount face. A correction ring is disposed to surround the target substrate placed on the mount face of the second electrode. The correction ring includes a combination of a first ring to be around the target substrate and a second ring arranged around or above the first ring. A power supply unit is configured to apply a first electric potential and a second electric potential respectively to the first ring and the second ring to generate a potential difference between the first and second rings. The power supply unit is configured to variably set the potential difference.

A plasma processing method includes executing an etching process that includes supplying an etching gas into a process container in which a target substrate is supported on a second electrode serving as a lower electrode, and applying an RF power for plasma generation and an RF power for ion attraction to turn the etching gas into plasma and to subject the target substrate to etching. The etching process includes applying a negative DC voltage to a first electrode serving as an upper electrode during the etching to increase an absolute value of self-bias on the first electrode. The etching process includes releasing DC electron current generated by the negative DC voltage to ground through plasma and a conductive member disposed as a ring around the first electrode, by using a first state where the conductive member is connected to a ground potential portion.

A plasma processing method includes executing an etching process that includes supplying an etching gas into a process container in which a target substrate is supported on a second electrode serving as a lower electrode, and applying an RF power for plasma generation and an RF power for ion attraction to turn the etching gas into plasma and to subject the target substrate to etching. The etching process includes applying a negative DC voltage to a first electrode serving as an upper electrode during the etching to increase an absolute value of self-bias on the first electrode. The etching process includes releasing DC electron current generated by the negative DC voltage to ground through plasma and a conductive member disposed as a ring around the first electrode, by using a first state where the conductive member is connected to a ground potential portion.

A plasma etching apparatus includes an upper electrode and a lower electrode, between which plasma of a process gas is generated to perform plasma etching on a wafer W. The apparatus further comprises a cooling ring disposed around the wafer, a correction ring disposed around the cooling ring, and a variable DC power supply directly connected to the correction ring, the DC voltage being preset to provide the correction ring with a negative bias, relative to ground potential, for attracting ions in the plasma and to increase temperature of the correction ring to compensate for a decrease in temperature of a space near the edge of the target substrate due to the cooling ring.