Dynamic ion radical sieve and ion radical aperture for an inductively coupled plasma (ICP) reactor

A chamber for plasma processing of semiconductor substrates, comprising:

• a substrate support;
• a plasma source opposite the substrate support;
• an ion filter disposed between the plasma source and the substrate support;
• a focus plate disposed between the ion filter and the substrate support, the focus plate coupled to a linear actuator, wherein the focus plate comprises a central aperture and a baffle extending from an edge portion of the focus plate toward the substrate support, and wherein the central aperture has a larger area than a substrate receiving surface of the substrate support;
• and
• an actuator operable to control elevation of the focus plate.

A plasma etch apparatus, comprising:

• a chamber;
• a plasma source disposed at one side of the chamber;
• a substrate support disposed opposite the plasma source, with a stage facing the plasma source;
• an ion-radical shield disposed between the plasma source and the substrate support, the ion-radical shield having a plurality of apertures formed in a region of the ion-radical shield aligned with the stage, the region of the ion-radical shield through which the apertures are formed having areal extent larger than the stage;
• and
• an aperture plate disposed between the ion-radical shield and the substrate support, the aperture plate having a central aperture substantially the same size as the region of the ion-radical shield through which apertures are formed, wherein the aperture plate is coupled to a linear actuator by a lift ring and a plurality of lift supports extending from the lift ring and contacting the aperture plate.