A bellows which forms a flexible coupling between the lid of a processing chamber and an antenna feed through. One embodiment provides an apparatus comprising a chamber body having a chamber lid, a feed through extending through the chamber lid, an antenna coupled to and extending through the feed through to an internal volume of the chamber body, and a bellows comprising a first flange, the first flange coupled to the feed through, a second flange, the second flange coupled to the chamber lid, and a center portion extending between the first flange and the second flange.