A Novel Capacitance-Coupling-Triggered SCR for Low-Voltage ESD Protection Applications

A novel capacitance-coupling-triggered silicon-controlled rectifier (CCTSCR) for on-chip electrostatic discharge (ESD) protection is proposed and verified in a 65-nm logic CMOS process. The trigger voltage of the CCTSCR can be adjusted by using a variable coupling capacitor, and a low trigger voltage of 2.15 V can be achieved through increasing the coupling capacitance. Compared with the conventional diode-triggered SCR, the CCTSCR has a similar robustness but a lower leakage current, particularly at an elevated temperature. The CCTSCR is suitable for I/O ESD protection of low-voltage CMOS integrated circuits.