Aluminium/polyimide adhesion

AbstractWe present a theoretical study of the interactions between isolated aluminium atoms and a polyimide surface and between polyimide and aluminium surface. The effect of surface modification on adhesion is also discussed. Self-consistent geometry optimization and molecular orbital calculations have been carried out within CNDO approximation in a cluster model framework. Our results suggest that aluminium atoms react preferentially with five and six-fold rings of polyimide when those chemical groups are present on the surface. The compound formation is accompanied by charge transfer from the metal atoms to polyimide and charge rearrangement among the polyimide atoms. Madelung potential calculations also suggest considerable core level shifts at polyimide atoms far from the reaction site. The adhesion of polymide to aluminium surface is predicted to be somewhat weaker than that of aliminium to polyimide