Toyota develops Diamond-like chips for Hybrid cars to boost fuel efficiency

Toyota Motor Corp. in collaboration with Denso Corp. and Toyota Central R&D labs. Inc. has developed a silicon carbide used as a power semiconductor in automotive power control units. This material is nearly as hard as a diamond, which makes it one of the hardest materials in nature.

Left:Silicon power semiconductor wafer (transistor)

Right:SiC power semiconductor wafer (transistor)

“A key way to improve fuel efficiency is to improve power semiconductor efficiency,” Kimimori Hamada, a Toyota engineer, said in a media briefing.

Toyota hopes to cut hybrid vehicle fuel consumption by up to 10 percent by introducing diamond-like silicon carbide (SiC) semiconductors in power control units in cars such as its Prius by 2020. Test driving vehicles with this technology are to be released on public roads in Japan within a year.

Right: PCU with silicon power semiconductors(Production model) 

Left: PCU with SiC power semiconductors(Future target)

“In December last year, Toyota established a clean room for dedicated development of SiC semiconductors at its Hirose Plant, which is a facility for research, development and production of devices such as electronic controllers and semiconductors.”

Toyota says this allows the engineers to reduce the size of the coil and capacitor in the hybrid vehicle power control unit (PCU) by 80 percent.

“In addition to improving engine and aerodynamic performance, Toyota is positioning high efficiency power semiconductors as key technology for improving fuel efficiency for HVs and other vehicles with electrified powertrains,” the company said. 

“Going forward, Toyota will continue to boost development activities aimed at early implementation of SiC power semiconductors.”