Denso develops its first inverter with SiC chips, used in Lexus RZ e-axle

Denso Coporation has developed its first-ever inverter with silicon carbide (SiC) semiconductors. This inverter, which is incorporated in the eAxle, an electric driving module developed by BluE Nexus Corporation, will be used in the new Lexus RZ. The RZ is Lexus’ first dedicated battery electric vehicle (BEV) model has been recently launched.

SiC power semiconductors consist of silicon and carbon that significantly reduce power loss compared to silicon (Si) power semiconductors. A cruising test conducted under specific conditions by BEVs using SiC semiconductor inverters demonstrated inverters with SiC power semiconductor reduce power loss less than half of ones with Si semiconductor. As a result, the energy efficiency of BEVs is improved and cruising range is extended.

According to Denso, SiC power semiconductors with Denso’s unique trench-type metal-oxide-semiconductor (MOS) structure improve the output per chip as they reduce power loss caused by heat generated. The unique structure achieved high voltage and low on-resistance operation.

Denso  inverter, which is incorporated in the eAxle, an electric driving module developed by BluE Nexus Corporation, will be used in the new Lexus RZ EV.

Key elements of new inverter
Based on the high-quality technology jointly developed by Denso and Toyota Central R&D Labs, Denso utilises SiC epitaxial wafers. As a result, Denso has halved the number of crystal defects that prevent the device from operating normally due to the disorder of the atomic arrangement of the crystal. By reducing crystal defects, the quality of SiC power semiconductor devices used in vehicles and their stable production are ensured.

Denso calls its SiC technology ‘RevoSic’, and uses it to comprehensively develop technologies for products ranging from wafers to semiconductor devices and modules such as power cards.