A physical vapor deposition processing chamber is described. The processing chamber includes a target backing plate in a top portion of the processing chamber, a substrate support in a bottom portion of the processing chamber, a deposition ring positioned at an outer periphery of the substrate support and a shield. The substrate support has a support surface spaced a distance from the target backing plate to form a process cavity. The shield forms an outer bound of the process cavity. In-chamber cleaning methods are also described. In an embodiment, the method includes closing a bottom gas flow path of a processing chamber to a process cavity, flowing an inert gas from the bottom gas flow path, flowing a reactant into the process cavity through an opening in the shield, and evacuating the reaction gas from the process cavity.