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Abstract: A novel method (the V-shaped curve) is presented to predict the failure probability of anisotropic conductive film (ACF) in IC/substrate assemblies. The Poisson function is used to calculate the probability of opening failure in the vertical gap between the pads, while the box and modified box models are used to estimate the probability of bridging failure between the pads in the pitch direction. The opening and bridging probabilities are combined using probability theory to establish four different failure prediction models. The results reveal that the model combining the Poisson function for fewer than six particles per pad with the modified box model provides the most accurate predictions of the failure probability of ACF in IC/substrate assemblies. [Copyright &y& Elsevier]

This paper designs a new multilayered particle anisotropic conductive film (ACF) compound. Using the particle-reinforced composite model and probability theory, the novel ACF compound is compared with three traditional ACFs having the same particle volume fraction. The particle-reinforced model applies the concept of bonded and debonded structures in the interfaces between the adhesive resin and the particles. The elastic modulus of the particle-reinforced ACF is a function of the particle volume fraction and the bonded condition. In the failure model, probability theory is used to calculate the probability of opening and bridging. The volume fraction of the conductive particles plays an important role in determining the optimal ACF design. The current results indicate that the flip chip packaging performed using the novel multilayered particle ACF compound (particles distributed in the top/bottom surface layers) exhibits superior particle-reinforcement properties and a lower failure probability than traditional ACFs. The improved understanding of reinforcement mechanisms and failure probability developed by this study facilitates the enhanced design of novel ACF compounds. [ABSTRACT FROM PUBLISHER]

This paper develops a model for predicting the failure probability of flip chip packaging using anisotropic conductive adhesive (ACA). The proposed approach modifies the box model to improve the accuracy of the bridging probability estimation by considering bridging in all directions. In the current failure analysis, probability theory is applied to calculate the probability of both opening and bridging failure. The Poisson distribution is used to calculate the probability of opening in the vertical gap between the pads, while the modified box model is used to estimate the probability of bridging between the pads. The results indicate that the modified box model provides an effective means of accurately estimating the probability of failure. The failure analysis takes the volume fraction of the conductive particles as the major variable in defining the optimal ACA design condition. A V-shaped curve model can be employed to establish an appropriate value of the volume fraction as a function of conductive particle radius, pitch, and pad dimensions such that the overall probability of failure is minimized. [ABSTRACT FROM PUBLISHER]