Abstract: An improved pre-clean chamber of a semiconductor processing system minimizes the generation of particulates during processing, thereby decreasing contamination levels that can adversely affect plasma vapor deposition film properties while also decreasing operational costs. The pre-clean chamber comprises an insulator collar that insulates the outside diameter surface of a wafer pedestal, thereby mitigating the etching of the wafer pedestal during etching. The pre-clean chamber further comprises a gas trench cover that directs a suitable etching gas from a gas inlet trench into streams that are focused up and towards the center of the chamber to reduce the extent to which gas bombards the chamber cover. The pre-clean chamber also comprises a bellows cover which protects the bellows of a wafer lift during etching, further reducing the dislodgment of particulates during etching.