Plasma confinement structures in plasma processing systems

A plasma processing chamber having therein a movable plasma confinement structure in said plasma processing chamber during plasma processing of a substrate, said plasma processing chamber having a plasma region wherein plasma is generated, said plasma region disposed above a lower electrode and between an upper electrode and said lower electrode, comprising:

• a cylindrical-shaped movable electrically conductive structure;
• a cylindrical-shaped movable plasma-facing structure, configured to surround said plasma region that is disposed above said lower electrode and between said upper electrode and said lower electrode to confine a plasma in said plasma region, said cylindrical-shaped movable electrically conductive structure is coupled to said cylindrical-shaped movable plasma-facing structure with a thermal expansion gap therebetween;
• a cylindrical-shaped movable electrically conductive structure disposed outside of said movable plasma-facing structure, wherein both said movable plasma-facing structure and said movable electrically conductive structure are retractable in a direction parallel to a cylindrical axis of said plasma processing chamber, wherein said movable plasma-facing structure is disposed between said plasma and said movable electrically conductive structure during said plasma processing such that at least a portion of RF current from said plasma flows to said movable electrically conductive structure through said movable plasma-facing structure during said plasma processing;
• and
• a conductive structure coupled to said movable electrically conductive structure, said movable electrically conductive structure conducting said at least a portion of RF current to ground during said plasma processing.

A plasma processing chamber for plasma processing of a substrate using plasma, said plasma processing chamber having a plasma region wherein said plasma is generated, said plasma region disposed above a lower electrode and between an upper electrode and said lower electrode, said plasma processing chamber having therein a movable plasma confinement structure that is movable during processing of said substrate, comprising:

• movable plasma-facing means, said plasma-facing means being cylindrical-shaped and formed of a first material and configured to surround said plasma region that is disposed above said lower electrode and between said upper electrode and said lower electrode to confine a plasma in said plasma region;
• movable electrically conductive means disposed outside of said movable plasma-facing means, said movable electrically conductive means formed of an electrically conductive material that is different from said first material, said movable electrically conductive means is coupled to said movable plasma-facing means and has a thermal expansion gap therebetween, wherein both said movable plasma-facing means and said movable electrically conductive means are retractable in a direction parallel to a cylindrical axis of said plasma processing chamber, wherein said movable plasma-facing means is disposed between said plasma and said movable electrically conductive means during said plasma processing such that at least a portion of RF current from said plasma flows to said movable electrically conductive means through said movable plasma-facing means during said plasma processing;
• and
• a conductive structure coupled to said movable electrically conductive means, said movable electrically conductive structure conducting said at least a portion of RF current from said movable electrically conductive means to ground during said plasma processing.