ESD protection circuit located under protected bonding pad

摘要

A circuit for protecting a bonding pad of a semiconductor device from ESD voltages is located under the pad to permit the space otherwise used for a protection circuit to be used for normal operating components. The protection circuit has a compact layout that provides maximum ability to handle an ESD current within this limited space. The semiconductor structure for the circuit has separate parts for two SCR circuits, one for each polarity of ESD current. Each SCR circuit comprises two symmetrical SCR structures.