Plasma processing apparatus

摘要

A plasma processing apparatus includes: a radio frequency (RF) power source which applies an RF power to a lower electrode; a direct current (DC) power source which applies a DC voltage to an upper electrode; a ground member for the DC voltage that is a ring shape formed of a conductive material, that is arranged in the processing chamber such that at least a part of the ground member is exposed to the processing space, and that forms a ground potential with respect to the DC voltage applied to the upper electrode; and a plurality of vertical movement mechanisms which move the ground member for the DC voltage in a vertical direction to adjust a grounding state of the ground member for the DC voltage.

主权项

1. A plasma processing apparatus comprising:
a processing chamber having a processing space inside; a lower electrode arranged in the processing chamber and functioning as a holding stage where a substrate is held; an upper electrode arranged in the processing chamber to face the lower electrode; a radio frequency (RF) power source which applies an RF power to the lower electrode; a direct current (DC) power source which applies a DC voltage to the upper electrode; a processing gas supply mechanism which supplies a processing gas to the processing space, the processing gas being plasmatized in the processing space; a ground member for the DC voltage which has an overall ring shape, is formed of a conductive material, is arranged to surround the lower electrode in a position lower than a substrate-holding position of the holding stage in the processing chamber such that at least a part of the ground member is exposed to the processing space, and forms a ground potential with respect to the DC voltage applied to the upper electrode; a focus ring of a circular shape which is arranged in a position higher than the ground member, and around the holding stage so as to surround the substrate-holding position; and a plurality of vertical movement mechanisms which are configured to move the ground member for the DC voltage in a vertical direction to adjust a grounding state of the ground member for the DC voltage, wherein the ground member is in a state of being connected to a ground potential when the ground member is in a descended state and a bottom portion of the ground member contacts a grounded source, and the ground member is in a state of being electrically floated when the ground member is ascended by the vertical movement mechanisms and the bottom portion of the ground member does not contact the grounded source, wherein the vertical movement mechanisms are configured such that a height of uppermost portion of the ground member ascended by the vertical movement mechanisms is lower than the height of the substrate-holding position of the holding stage.