Study on Adhesion Improvement of Polyimide Film

Polyimide (PI) materials have been widely used as stress buffer and rewiring cover layers to improve semiconductor reliability. As these applications require compatibility with various organic and/or inorganic materials, the effect of plasma treatment on the adhesion of PI to an anisotropic conductive film (ACF) and an under-fill molding compound (UF) was investigated. In this paper, several gases were tested and the results found that N2 plasma treatment of the PI film produced an improvement in the adhesion of the PI to both ACF and UF due to stronger bonding at the interface.