Electrostatic discharge (ESD) is one of the most prevalent threats to the reliability
of electronic components. It is an event in which a finite amount of charge is trans-
ferred from one object (i.e., human body) to another (i.e., microchip). This process
can result in a very high current passing through the microchip within a very short
period of time, and, hence, more than 35% of chip damages can be attributed to an
ESD-related event. As such, designing on-chip ESD structures to protect integrated
circuits against the ESD stresses is a high priority in the semiconductor industry.
