SEMICONDUCTOR New carbide power semiconductors for fuel cell vehicles
In December, DENSO Corporation announced that it has begun mass production of its latest model of booster power module equipped with silicon carbide power semiconductors, as part of its efforts to achieve a low-carbon society. This product is used in Toyota’s new Mirai model.
DENSO has developed its REVOSIC®1 technology for the purpose of applying Silicon Carbide (SiC) power semiconductors (diodes and transistors) to in-vehicle applications. SiC is a semiconductor material having superior performance in high-temperature, high-frequency, and high-voltage environments compared with conventional silicon (Si).
Thus, the use of SiC for key devices has attracted much attention in order to significantly reduce the power loss, size, and weight of systems and accelerate electrification. In 2014, DENSO launched a SiC transistor for non-automotive applications and commercialized it for audio products. The company continued to conduct research for in-vehicle applications, and in 2018, Toyota used an in-vehicle SiC diode was used in its Sora fuel cell buses.
Now, DENSO has developed a new in-vehicle SiC transistor, and this marks the first time the compan has used SiC for in-vehicle diodes and transistors. The newly developed SiC transistor offers both high reliability and high performance in in-vehicle environments, which can challenge semiconductors.
The new model of booster power module2 equipped with the SiC power semiconductors (diodes and transistors) is about 30% smaller in volume and provides roughly 70% less power loss compared to a conventional product equipped with Si power semiconductors, helping to reduce the size of the booster power module and improve vehicle fuel efficiency.
DENSO remains committed to conducting R&D on REVOSIC® technology, expanding the application of the technology to electric vehicles, including hybrid electric vehicles and battery electric vehicles, and thereby helping to build a low-carbon society.
1) REVOSIC® is a generic term for DENSO’s SiC technology for achieving high quality and low loss. The technology was named REVOSIC because it aims to revolutionize society by using innovative SiC technology. DENSO has been developing comprehensive technologies, including the highest-quality wafers in the industry (extremely low defect density) and highly efficient power modules.
2) A booster power module drives multiple SiC power semiconductors that are built into the module to output a higher voltage than the input voltage.