Low Voltage NIPIN Symmetric and Bi-Directional Diode for System Level ESD Protection

Abstract

Low voltage (<1V) bi-directional and symmetric electrostatic discharge (ESD) protection devices are essential for system level ESD protection of low voltage electronics such Low voltage GPIO for MCU, Sub-20nm I/O’s, and potentially for next gen interfaces USB3.2 Gen2, Thunderbolt 4. Here, a triangular barrier designed Silicon NIPIN (n+ -i-p+ -i-n+) punch-through diode with variable voltage <0.5V to 2V is proposed for low-voltage system level ESD protection. The NIPIN diode utilizes the sub-bandgap voltage impact ionization to enable the ultra-low voltage breakdown. The control over the breakdown voltage is demonstrated via TCAD simulations by controlling the lengths of intrinsic, and p+ -doped regions and the doping of p+ -doped region. Finally, standoff voltage and clamping voltages are compared with other low voltage protection devices and demonstrate near ideal voltage performance of the NIPIN protection device. Such a low voltage ESD protection with low clamping voltage is a critical development for low-voltage electronics.