Drain-Extended FinFET With Embedded SCR (DeFinFET-SCR) for High-Voltage ESD Protection and Self-Protected Designs

This article presents device design insights and design challenges for drain-extended FinFET devices with embedded silicon-controlled rectifier (SCR) (DeFinFET-SCR), which can be used as an electrostatic discharge (ESD) protection device and a self-protected high-voltage switch/driver for system-on-chip applications. The tradeoff between maximizing ESD robustness without hindering the transistor's operation is discussed in detail. An interplay between parasitic p-n-p turn-on and space charge modulation (SCM) is revealed, which strongly influences the strength of parasitic SCR and its turn-on efficiency during ESD and DC operations. Developed physical insights show that engineering p-n-p turn-on and onset of SCM are the key to maximize ESD robustness without causing early SCR turn-on during transistor operation. Based on new findings and developed physical insights, design guidelines have been derived for ESD robust DeFinFET-SCR.