Plasma processing device and retractable sealing part thereof

A plasma processing device, comprising:

• a process chamber;
• an upper electrode arranged in the process chamber and a lower electrode arranged opposite to the upper electrode, wherein relative positions of the upper electrode and the lower electrode are adjustable, so that a distance between the upper electrode and the lower electrode is adjustable;
• at least one radio-frequency power supply connected to the upper electrode or the lower electrode;
• and
• a retractable sealing part, arranged in or near a radio-frequency circuit between the upper electrode and the lower electrode, and extending and retracting with a change of the relative positions of the upper electrode and the lower electrode;
• wherein the retractable sealing part comprises:
• a bellows assembly, having a first end and a second end;
• a sleeve assembly, comprising a first sleeve and a second sleeve, wherein the first sleeve is arranged close to the first end of the bellows assembly, and the second sleeve is arranged close to the second end of the bellows assembly;
• free ends of the first sleeve and the second sleeve are overlapped with each other to form a radio-frequency shielding space when the first sleeve and the second sleeve slide relatively;
• wherein the bellows assembly is located in the radio-frequency shielding space, and the sleeve assembly is a conductor;
• and
• further comprising an insulating buffer layer arranged between the first sleeve and the second sleeve, the insulating buffer layer contacts the first sleeve and the second sleeve, respectively.