Novel LDNMOS embedded SCR with strong ESD robustness based on 0.5 μm 18 V CDMOS technology

WANG Yang(汪洋)^{1, 2}, JIN Xiang-liang(金湘亮)^{1, 2}, ZHOU A-cheng(周阿铖)^{1, 2}

(1. Faculty of Materials, Optoelectronics and Physics, Xiangtan University, Xiangtan 411105, China;
2. Hunan Engineering Laboratory for Microelectronics, Optoelectronics and System on a Chip, Xiangtan 411105, China)

Abstract:A novel LDNMOS embedded silicon controlled rectifier (SCR) was proposed to enhance ESD robustness of high-voltage (HV) LDNMOS based on a 0.5 μm 18 V CDMOS process. A two-dimensional (2D) device simulation and a transmission line pulse (TLP) testing were used to analyze the working mechanism and ESD performance of the novel device. Compared with the traditional GG-LDNMOS, the secondary breakdown current (I_t2) of the proposed device can successfully increase from 1.146 A to 3.169 A with a total width of 50 μm, and ESD current discharge efficiency is improved from 0.459 mA/μm² to 1.884 mA/μm². Moreover, due to their different turn-on resistances (R_on), the device with smaller channel length (L) owns a stronger ESD robustness per unit area.

Key words:LDNMOS embedded SCR; TCAD simulation; electrostatic discharge (ESD) robustness; transmission line pulse (TLP)