Prolonged 500 °C Demonstration of 4H-SiC JFET ICs With Two-Level Interconnect

This letter reports fabrication and testing of integrated circuits (ICs) with two levels of interconnect that consistently achieve greater than 1000 h of stable electrical operation at 500°C in air ambient. These ICs are based on 4H-SiC junction field-effect transistor technology that integrates hafnium ohmic contacts with TaSi2interconnects and SiO2and Si3N4dielectric layers over ~1-μm scale vertical topology. Following initial burn-in, important circuit parameters remain stable within 15% for more than 1000 h of 500°C operational testing. These results advance the technology foundation for realizing long-term durable 500°C ICs with increased functional capability for sensing and control combustion engine, planetary, deep-well drilling, and other harsh-environment applications.