An Enhanced MLSCR Structure Suitable for ESD Protection in Advanced Epitaxial CMOS Technology

摘要

In this paper, an enhanced modified lateral silicon-controlled rectifier (EMLSCR) has been proposed and demonstrated. Compared with the traditional MLSCR, the EMLSCR possesses a lower trigger voltage of 7.0 V as well as a higher robustness, making it very suitable for the electrostatic discharge (ESD) protection for 2.5-V/3.3-V/5-V IOs in the advanced 65-nm epitaxial CMOS technology. Additionally, an improved transmission line pulsing (TLP) measurement strategy by adopting TLP pulses with various rise time has been put forward to provide a convenient and economical approach to explore the conduction uniformity of the ESD device for the first time. Furthermore, two optimization methods are proposed and evaluated to overcome the prefailure issue due to the small well resistance inherited in the EPI process as well. The method of well pickup segmentation is demonstrated to be more efficient since it could increase the well resistance and augment the effective emitter area of parasitic bipolar junction transistors (BJTs) under constant device area.