From a part to a process
Kyoto University and Japanese chipmaker Phenitec Semiconductor moved silicon-carbide transistor fabrication from small samples to a 150 mm wafer. Both n-type and p-type devices operated on that wafer. The useful unit here is a set of parts made by the same process that could eventually form a circuit, rather than one working transistor.[1]
The strongest measurement has a clear boundary: in the central 90 mm region, threshold-voltage standard deviation was below 0.07 V. That voltage determines when each device starts conducting. A narrow spread addresses one prerequisite for assembling a circuit. The university gives no matching figure for the entire wafer, so the number cannot stand in for full-wafer yield.[1]
The path to a circuit
An earlier study reported a device operating at 600 °C. The new conference result concerns manufacturing scale. Phenitec's fabrication plant supplied the large-wafer process. It shows which part of the laboratory result crossed into a production setting: the transistor fabrication steps developed for small samples.[1]
The next engineering test is to connect many such devices into a working integrated circuit and establish uniformity across the wafer. Kyoto University names jet-engine sensors, geothermal work and Venus exploration as possible uses. The reported demonstration does not include a system operating in those environments. These are conference findings, with no journal paper yet published.[1]