Patent ID: 7192878

Claim:
A method for removing post-etch residues from surfaces of a wafer, comprising: depositing at least one low-k (k<3) dielectric film on said wafer; depositing a metal layer over said low-k dielectric film; forming a resist pattern over said metal layer; transferring said resist pattern to said metal layer to form a metal pattern; stripping said resist pattern; plasma etching a through hole into said low-k dielectric film by using said metal pattern as a hard mask, wherein said plasma etching causes residues to deposit within said through hole; performing a first wet treatment to soften said residues; after performing said first wet treatment, performing a plasma dry treatment to crack said residues, the plasma dry treatment comprising; exposing said wafer and said softened residues to an oxidizing plasma atmosphere with the presence of oxygen and hydrogen; followed by exposing said wafer and said residues to a reducing plasma atmosphere with the absence of oxygen; and after performing said plasma dry treatment, performing a second wet treatment to completely remove said residues.