SiC Lateral Diodes for ESD Protection of High Temperature Integrated Circuits

Abstract

Lateral diode based electrostatic discharge (ESD) protection for silicon-on-insulator (SOI) circuits suffer from high leakage currents at elevated temperatures. This may degrade the performance of SOI based integrated circuits and can also limit the life of the system. Wide bandgap materials such as silicon carbide (SiC) can potentially mitigate this problem because of their low intrinsic carrier concentrations. In this study, lateral SiC diodes have been fabricated and evaluated at high temperatures for ESD protection. The leakage level of SiC lateral diodes with an active area of 700 μm2 is shown to be as low as 1 pA at 200 °C and 25 pA at 300 °C. Furthermore, based on circuit simulations, the number of lateral SiC diodes required to protect against an ESD event (human body model) at 2kV was determined to be 20 devices. Under reverse bias conditions (at 20V), these diodes would have a total leakage current of 20 pA at room temperature and 500 pA at 300 °C. .