Understanding the Failure Mechanisms of Protection Diodes During System Level ESD: Toward Repetitive Stresses Robustness

In electronic systems, the ever-increasing level of integration is paced by component scaling. Consequently, system-level protection improvements in electrostatic discharge (ESD) reliability during a device's lifetime are mandatory. To this end, we have investigated bidirectional system-level ESD protection diodes that have been subjected to repetitive human metal model stresses. Our goal was to develop robust ESD components by understanding the physical and electrical behaviors of components after multiple ESD surges. In this paper, three ESD-induced failure modes of protection devices are demonstrated and analyzed in terms of severity, i.e., charge trapping in the silicon-oxide interface, metallic diffusion toward the contacts, and melted filaments in the silicon bulk at the junction periphery.