Characterisation of Polyimide‐glass‐metal Joints Bonded with Anisotropic Electrically Conductive Adhesives

Abstract

Tape automated bonding (TAB) circuits were joined by hot compression bonding to copper or nickel conductors on glass with two anisotropic electrically conductive adhesives. One of the adhesives had a thermoplastic polystyrene‐polyester matrix which contained easily deforming metal‐coated polymer particles, while the other was a thermosetting bisphenol (A) based epoxy resin filled with nickel particles. The resistance values and the mechanical strengths of the joints were measured before and after the ageing treatments. The thermoplastic adhesive had the lowest resistance values with copper conductors and the joints produced with this adhesive showed increasing strength values during the ageing tests. The joints between the Ni conductors had smaller values of electrical conductivity irrespective of the adhesive used. The SEM/EPMA technique revealed that particles of the thermoplastic adhesive tended to agglomerate. This may cause problems when components with very fine lead pitch are joined, either by short circuiting or leaving some contacts without particles.

Citation

Savolainen, P. and Kivilahti, J. (1996), "Characterisation of Polyimide‐glass‐metal Joints Bonded with Anisotropic Electrically Conductive Adhesives", Microelectronics International, Vol. 13 No. 2, pp. 13-16. https://doi.org/10.1108/13565369610800287