Field effect diode for effective CDM ESD protection in 45 nm SOI technology

Abstract

In this paper, the improved field-effect diode (FED) has been characterized and modeled in 45 nm silicon-on-insulator (SOI) technology. It has been experimentally shown to be suitable for pad-based local clamping under normal supply voltage (Vdd) range (below 1 V) in high-speed integrated circuits. ESD protection capabilities are investigated using very fast transmission line pulse (VF-TLP) tests to predict the device's performance in charged device model (CDM) ESD events. The FED's advantages in improving transient turn-on behavior and reducing DC leakage current have been analyzed and compared with other Silicon-Controlled-Rectifier (SCR)-based SOI device variations. Technology CAD (TCAD) simulations are used to interpret the turn-on behavior and the physical effects. Process tradeoffs have been evaluated. The work prepares the device for being directly applied to high-speed Input/Output (I/O) circuit and it addresses the severe challenge in CDM ESD protection. The improved device enables the adoption of local clamping scheme that expands the ESD design window.