Gate-controlled field-effect diodes and silicon-controlled rectifier for charged-device model ESD protection in advanced SOI technology

Silicon-controlled rectifier (SCR) devices are used as local clamping ESD devices. However, conventional designs suffer from slow turn-on, which causes problems in sub 10 ns charged-device model (CDM) protection, especially in deeply scaled technologies. In this paper, a double-well field-effect diode (DWFED) and an improved field-effect diode (FED) are designed to address this challenge. They are fabricated and characterized in 45 nm silicon-on-insulator (SOI) technology and experimentally demonstrated to be suitable for pad-based local clamping under a normal supply voltage (Vdd) range (at or below 1 V) in high-speed applications. ESD protection capabilities are investigated using very fast transmission line pulse (VF-TLP) tests to predict the device performance in CDM events. FED’s advantages in improving transient turn-on behavior and reducing DC leakage current are analyzed and compared with the regular SCR and the DWFED. Technology CAD (TCAD) simulations are used to interpret turn-on behavior and guide design. The improved devices may be implemented in a local clamping scheme that expands the ESD design window for advanced technology nodes.