Damage of Flexible Ag Line Covered with Insulating Layer under High Density Current

Abstract

The demand for flexible electronic circuits is increasing with the development of wearable devices. The downsizing of electronic circuits with the aim of miniaturization and high functionalization of electronic devices increases the electrical current flowing through the line. The increase in current density causes electromigration (EM), which is the migration of metal atoms due to electron’s collision and EM eventually leads to wire breakdowns. Therefore, clarifying the mechanism of EM damages and predicting the lifetime of electronic lines are important for evaluating the reliability of electronic devices. In addition, electronic line is usually coated with insulating layer to protect the line from the influence of external environment. Although high-density current loading tests have been conducted on flexible Ag nanoparticle lines in previous studies, the effects of insulating layer on the EM damages of the lines have not been fully clarified. In this study, high-density current loading tests were conducted to investigate the effect of the insulating layer on the EM behavior. In the experiments, Ag nanoparticle lines were fabricated on flexible substrates with and without insulating layer coating. And the characteristics of EM damages were evaluated under different density current loading.