A New SCR-LDMOSFET Embedded P-Region for Electrostatic Discharge Protection

Abstract

In this paper, a new Silicon Controlled Rectifier and Lateral Double-diffused Metal-Oxide-Semiconductor Field Effect Transistor with shallow P-region (SPSCR- LDMOSFET) is proposed for electrostatic discharge (ESD) protection. The shallow P-region junction causes P-region/N- epi junction being apt to avalanche breakdown. So, trigger voltage is reduced. Furthermore, a new parasitic PNP transistor including the P-region as collector provides another leakage channel for ESD current and then the conductivity modulation in the SCR is weakened. As a result, holding voltage is increased. The physics mechanism of the above high performance is investigated via Technology Computer Aided Design (TCAD) simulation under ESD condition. We also present a detailed analysis of the current paths at trigger point, holding point and second breakdown point.