Electric Field Assisted Self-Healing (eFASH)

Abstract

Circuit failure due to the open faults in the interconnect is the most common problem regarding the reliability of electronic systems. This is particularly true for large-area electronic systems such as display, image sensor arrays, as well flexible and wearable electronic systems. To address this problem, various techniques to repair fractured interconnect in real-time have been investigated. One approach that is of interest to this work is the electric field-assisted self-healing (eFASH). The eFASH technique involves the use of a low concentration dispersion of conductive particles in an insulating fluid that is encapsulated over interconnect. When a current-carrying interconnect is fractured an electric field appears across the open fault. This field polarizes the conductive particles, subsequently chains them up to create a heal. This work discusses the mechanism of self-healing and studies the impact of the dispersion concentration on the healing time, heal impedance and cross-talk. Theoretical predictions have been substantiated by experimental evidence and an optimum dispersion concentration for effective self-healing is identified. The application of eFASH for stretchable electronics also has been studied and stretchable heals having a conductivity about 5 * 10^5 S/m and allowing strains from 12 to 60 during stretching have been demonstrated.