Design of low-leakage power-rail ESD clamp circuit with MOM capacitor and STSCR in a 65-nm CMOS process

A power-rail electrostatic discharge (ESD) clamp circuit designed with low-leakage consideration has been proposed and verified in a 65-nm low-voltage CMOS process. By using the metal-oxide-metal (MOM) capacitor in the ESD-detection circuit, the power-rail ESD clamp circuit realized with only thin-oxide (1-V) devices has very low stand-by leakage current, as compared to the traditional design. The experimental results in the silicon chip showed that the standby leakage current is only 358 nA at room temperature (25 °C) under the power-supply voltage of 1 V, whereas the traditional design realized with the NMOS capacitor is as high as 828 µA under the same bias condition.