Low-Capacitance SCR With Waffle Layout Structure for On-Chip ESD Protection in RF ICs

Silicon-controlled rectifier (SCR) has been used as an effective on-chip ESD protection device in CMOS technology due to the highest ESD robustness. In this work, the waffle layout structure for SCR can achieve smaller parasitic capacitance under the same ESD robustness. With smaller parasitic capacitance, the degradation on RF circuit performance due to ESD protection device can be reduced. The proposed waffle SCR with low parasitic capacitance is suitable for on-chip ESD protection in RF ICs.