US Patent 8623148 NF

Methods of cleaning a processing chamber with nitrogen trifluoride (NF3) are described. The methods involve a concurrent introduction of nitrogen trifluoride and a reactive diluent into the chamber. The NF3 may be excited in a plasma inside the chamber or in a remote plasma region upstream from the chamber. The reactive diluent may be introduced upstream or downstream of the remote plasma such that both NF3 and the reactive diluent (and any plasma-generated effluents) are present in the chamber during cleaning. The presence of the reactive diluent enhances the chamber-cleaning effectiveness of the NF3.