On-Chip ESD Monitor

Electrostatic discharge (ESD) failure results in about 35% of IC field returns, and is the cause of several billiondollar loss to the semiconductor industry. An on-chip ESD detector can help track the electrostatic history of ICs from manufacturing to end-of-life. Two approaches for on-chip ESD detection are presented: variable dielectric width capacitor, and vertical MOSCAP array. The variable dielectric width capacitor approach employs metal plates terminated with sharp corners to enhance local electric field and facilitate easy breakdown of the thin dielectric between the metal plates. The vertical MOSCAP array consists of a capacitor array connected in series. Both approaches were simulated, fabricated, and experimentally characterized in GlobalFoundries 22 nm fully depleted silicon-oninsulator. Vertical MOSCAP arrays detect ESD events starting from ~6 V with 6V granularity, while the variable dielectric width capacitor is suitable for detection of high ESD voltage from 40 V and above.