Self-compliant seal assembly

A process station, comprising:

• a radio frequency (RF) generator;
• a chamber body defining a chamber volume;
• a pumping plate disposed in the chamber body;
• a substrate support disposed in the chamber body, the substrate support comprising:
• a seal plate;
• a self-compliant seal assembly, comprising:
• a compliant diaphragm having an inner rim and an outer rim, the inner rim being coupled with the seal plate and the outer rim forming a cavity;
• a spring element disposed in the cavity;
• and
• a compliant sheet disposed between the seal plate and the inner rim and between the outer rim and the pumping plate,
• wherein the spring element is arranged to bias the compliant sheet toward the pumping plate to form a compliant seal that isolates a first region from a second region of the chamber volume and forms a symmetric RF return path to the RF generator.

A self-compliant seal assembly for a process station, comprising:

• a compliant diaphragm having an inner rim, an outer rim, and a base wall extending between and connecting the inner rim and the outer rim, wherein the outer rim defines a cavity and a diaphragm channel is defined between the inner rim and the outer rim;
• a spring element disposed in the cavity;
• and
• a compliant sheet contacting the inner rim and the outer rim, wherein the compliant sheet encloses the diaphragm channel and the spring element within the cavity.