Analysis and prediction of electrical contact resistance for anisotropic conductive adhesives

Anisotropic conductive adhesives (ACAs) and anisotropic conductive films (ACFs) are promising solder alternatives. These materials are preferable for fine pitch and ultra-fine pitch connections in electronics assembly. Quality of these interconnections is usually evaluated with measurement of electrical resistance. This paper describes few simple models for prediction of electrical contact resistance in ACAs interconnects. Nevertheless in these models is usually neglected effect of thin insulating layer between conductive particles and conductive tracks on substrate. Therefore two different methods for evaluation of electron tunneling resistance are analyzed and implement into models for prediction of electrical contact resistance of ACAs/ACFs. Extended models are directly compared with experimental results. Also effect of bonding pressure and different materials of conductive tracks is analyzed.