Design of Dual-Directional SCR Structure With High Holding Voltage and Low Dynamic Resistance for High Voltage ESD Protection

This study introduces a novel dual-directional silicon-controlled rectifier (SCR) that offers enhanced holding voltage for increased latch-up immunity and robust high-voltage IC support for bidirectional electrostatic discharge (ESD) protection. By significantly enlarging the base of the parasitic bipolar junction transistor (BJT) and reducing the dynamic resistance across each terminal through a three-implant design, the proposed device demonstrates superior electrical properties. To showcase the improvements, a comparative analysis is conducted between the conventional low-trigger dual-directional SCR (LTDDSCR) and the gate-biasing high-holding dual-directional SCR (GHHDDSCR) device. A transmission line pulse (TLP) system is employed to validate the enhanced electrical properties of the proposed device. The efficient segment topology is implemented in conjunction with the optimization of the suggested design variables, taking into account the structural properties of the proposed device. Latch-up immunity is further verified through transient latch-up (TLU) assessments. Experimental results confirm the effectiveness of the proposed SCR for applications requiring 15 V or higher, showcasing its latch-up immunity in high-voltage scenarios, and improved design area efficiency.