The Influence of N-Type Buried Layer on SCR ESD Protection Devices

摘要

This article investigates the effect of N-type buried layer (NBL) on the holding voltage and failure current of conventional low voltage triggered silicon-controlled rectifier (LVTSCR) and conventional dual directional siliconcontrolled rectifier (DDSCR) devices. LVTSCR and DDSCR with N-type buried layer are fabricated on a 0.18-mu m Bipolar CMOS DMOS (BCD) technology. In order to verify and predict the effect of N-type buried layer on the characteristics of ESD protection devices, a transmission line pulse (TLP) testing system and a 2-dimension device simulation platform have been used in this work. According to the measurement results, the holding voltage (V-h) and failure current (I-t2) of the LVTSCR and DDSCR can be drastically improved by adding N-type buried layer.