Onset of electrical conduction in isotropic conductive adhesives: a general theory

Abstract

A new theory is introduced for the onset of electrical conduction in isotropic conductive adhesives, based on the observation that conduction is a result of the creation of conducting contacts in metal–insulator composite adhesives. The present theory resolves several prevalently contradicting issues including the onset dependency of electrical conduction on the volume fraction of filler particles, the particle size, the pressure effect, and the type of insulator matrix of an adhesive. The theory also predicts the condition for the occurrence of two percolation thresholds.