RC-Embedded LDMOS-SCR With High Holding Current for High-Voltage I/O ESD Protection

A novel lateral diffusion MOS-embedded silicon-controlled rectifier with a high holding current (LDMOS-SCR-HHC) is proposed and verified in a 0.25-μm 18-V Bipolar-CMOS-DMOS process. By adding an imbedded P+ region located next to the source region of an LDMOS-SCR and connecting the P+ region to the gate, the LDMOS-SCR-HHC exhibits a relatively HHC, small trigger voltage, and strong electrostatic discharge (ESD) robustness. As such, the proposed LDMOS-SCR-HHC is an attractive device for constructing effective and latch-up immune ESD protection solutions for high-voltage I/O ports.