A processing chamber for processing a substrate is disclosed herein. In one embodiment, the processing chamber includes a liner assembly disposed within an interior volume of the processing chamber, and a C-channel disposed in an interior volume of the chamber, circumscribing the liner assembly. In another embodiment, a process kit disposed in the interior volume of the processing chamber is disclosed herein. The process kit includes a liner assembly, a C-channel, and an isolator disposed in the interior volume. The C-channel and the isolator circumscribe the liner assembly. A method for depositing a silicon based material on a substrate by flowing a precursor gas into a processing chamber is also described herein.