Surface plasma treatments of protecting polyimide films of semiconductor devices have been applied to improve adhesion between polyimide and molding resin. Ar, N2 and 02 were used as plasma gases for surface treatments, and the difference of the surface properties for each plasma-treated polyimide film was studied The contact angle with glycerin decreased by N2 and 02 plasma treatments. The electrical resistivity of polyimide surface decreased with the Ar plasma treatment XPS (X-ray Photoelectron Spectroscopy) measurements revealed that the Ar plasma-treated polyimde surface was carbon rich and N2 and 02 plasma treated ones had large number of C=O and CN bonds. We believe that the carbon-rich layer makes the electrical conductive layer on the polyimide surface, and hydrophilic bondings (C=O, C-N) reduce the contact angle and improve adhesion between polyimide and molding resin.
