Continuous electrical resistance monitoring, pull strength, and fatigue life of isotropically conductive adhesive joints

Four isotropically conducting adhesives were used to form lap joints between copper fingers which had been prepared with four surface metallizations (Cu, Au, Pd, and PdNi). A micromechanical tester was used to perform pull and fatigue tests on the 16 adhesive/finish combinations. The micro-ohm resistance change was measured during both the pull and fatigue tests. The similarities and differences between the mechanical strength, fatigue life, and resistance change for the 16 adhesive/finish combinations are reported, and conclusions are drawn about relative motion between silver particles and the fracture interfaces.