Ladder-shaped network for ESD protection of millimetre-wave CMOS ICs

A compact ladder-shaped electrostatic discharge (ESD) protection circuit is presented for millimetre-wave integrated circuits (ICs) in CMOS technology. Multiple shorted shunt stubs form a ladder network together with series stubs as ESD protection that discharges current/voltage pulses caused by an ESD event, while at the same time the network is embedded as part of the matching circuit for a normal operation. A 60 GHz low-noise amplifier using a 90 nm CMOS process is demonstrated with the proposed ESD protection methodology that introduces less than 1 dB insertion loss. Owing to the ESD current distribution through multiple shorted stubs, the proposed methodology is useful to millimetre-wave ICs with advanced CMOS technology that suffers from higher sheet resistance of the metal layers.