Bellows seal for low thru-force actuation of temperature probe across vacuum interface

A system comprising:

• a substrate support arranged in a processing chamber under vacuum to support a substrate;
• an edge ring arranged around the substrate on the substrate support;
• a plasma tuning ring arranged adjacent to the edge ring in the substrate support;
• and
• an actuator assembly to actuate the plasma tuning ring, the actuator assembly comprising:
• an actuator coupled externally to the processing chamber, the actuator being at atmospheric pressure;
• a rod coupled to the actuator and to the plasma tuning ring;
• bellows arranged externally to the processing chamber between the actuator and the processing chamber, the rod passing through the bellows;
• and
• vacuum seals disposed between the bellows and the actuator and between the bellows and the processing chamber to seal the vacuum in the processing chamber from the atmospheric pressure external to the processing chamber.