Stable Electrical Operation of 6H–SiC JFETs and ICs for Thousands of Hours at 500 $^{\circ}\hbox {C}$

The fabrication and testing of the first semiconductor transistors and small-scale integrated circuits (ICs) to achieve up to 3000 h of stable electrical operation at 500degC in air ambient is reported. These devices are based on an epitaxial 6H-SiC junction field-effect transistor process that successfully integrated high-temperature ohmic contacts, dielectric passivation, and ceramic packaging. Important device and circuit parameters exhibited less than 10% of change over the course of the 500degC operational testing. These results establish a new technology foundation for realizing durable 500degC ICs for combustion-engine sensing and control, deep-well drilling, and other harsh-environment applications.