Mitsubishi Electric Corporation announced that it has developed a silicon carbide (SiC) power device with what is believed to be the world’s highest power efficiency in a device of its type. The newly-developed unit is designed to be installed in power modules, and does not require a high-speed protection circuit to interrupt supply when excess current is detected. The new device will help improve the reliability and energy efficiency of power electronics equipment used in a wide range of applications such as home electronics, industrial machinery and railway operation.

Mitsubishi Electric’s development of the new SiC device was first revealed at the 2017 International Conference on Silicon Carbide and Related Materials (ICSCRM 2017), held in Washington, D.C., September 17–22, 2017.

The superior reliability and efficiency of the new device is the result of a new proprietary source structure. In conventional metal-oxide-semiconductor field-effect transistors, known as MOSFETs, the source area is formed as a single region. However, Mitsubishi Electric has introduced an additional region in the source area to control the source series resistance of the SiC-MOSFET. Adopting this structure reduces the incidence of excessive current flows caused by short circuits. As a result, on the general short-circuit time used for Si power semiconductor devices, the on-resistance of the SiC-MOSFET is reduced by 40 percent at room temperature, and power loss by more than 20 percent, compared to conventional SiC-MOSFET devices.

A simplified circuit design allows the technology to be applied across SiC-MOSFETs with various voltage ratings. Tried and tested circuit technology is used to protect silicon components from damage in the event of short-circuits, and can be applied to existing SiC-MOSFETs without any need for modification. This guarantees easy implementation of protective functionality in power electronics equipment using SiC-MOSFETs.

This  TechNews Daily 2016.11.23