Mechanics Issues at Micro-Scale Modeling of Electronic Packages

Due to the temperature dependent material properties and low cycle thermo-mechanical fatigue of electronic packaging interconnects and components, plasticity theories are extensively used to understand their mechanical response in estimating the fatigue life. Experimental evidence indicates that plastic deformation at small scales depends not only on the state variables of stress and strain, but also on their higher order gradients. In this paper mechanics issues related to strain gradient plasticity at micron scale are reviewed through strain gradient enhanced continuum theories. A plastic strain gradient-based approach is employed to study the thermo-mechanical deformation of microvia structure.