Kyoto team demonstrates a SiC transistor at 600°C in lab

At 600°C, a transistor built by researchers at Kyoto University continued to work. The silicon carbide device operated successfully in tests from room temperature up to 600°C (1,112°F), according to the team’s study in APL Electronic Devices.

The component is a junction field-effect transistor, or JFET — a transistor controlled by an electric field. Earlier SiC JFETs made by the researchers used a conventional top-gate design and a semi-insulating substrate, but their voltage control weakened and their leakage current grew at high temperatures. Those two problems had stood in the way of practical use.

The Kyoto team changed the architecture rather than starting from scratch. It used a bottom-gate structure made with industry-standard manufacturing methods, improving control of the transistor’s threshold voltage. Well-based isolation replaced the semi-insulating substrate, reducing unwanted current until it came close to the theoretical limit predicted from SiC’s material properties. The new structure succeeded on the first attempt, the researchers report.

So what does that change in practice? It gives engineers a demonstrated building block for low-power integrated circuits designed to operate in extreme environments, rather than only a material with theoretical promise. The result is still a laboratory device, not a deployed system: Kyoto’s team says it must create more complex circuits, scale up to wafer-level production and ensure the full package can withstand extreme conditions.