ESD Protection Device With Dual-Polarity Conduction and High Blocking Voltage Realized in CMOS Process

Electrostatic discharge (ESD) protection devices fabricated in a low-voltage CMOS process for communication interface applications typically provide relatively small blocking voltage, thus limiting the interface operating voltage range for which the ESD device can be used. This letter introduces a CMOS-based silicon controlled rectifier with a large blocking voltage beyond ±20 V and a high trigger current. Such a high blocking voltage is achieved by selectively defining native-buffer regions in critical blocking junctions of the device. Experimental characterization of the ESD robustness and standing operation are presented to validate the new device for low capacitance, high-voltage-tolerant communication interface ESD protection applications.