SILICON CARBIDE (SiC)

Silicon carbide (SiC) semiconductors have been known for decades, yet only in the past twenty years have its semiconducting properties been adequately studied and applied. Presently under heavy development is the fabrication of SiC power electronic transistors such as MOSFETs, JFETs, IGBTs, GTOs, diodes, etc... SiC is rapidly becoming the semiconductor choice for advanced applications where improved high temperature, harsh environment, high voltage, and high power density performance is required.

The fundamental properties of traditional semiconductor materials, such as silicon, limit the operating performance of electronic devices and components to a narrow range of conditions. Power electronics based upon silicon transistor technology have reached design limits on weight, size, and efficiency due to heating. Current silicon power electronic devices are limited by a junction temperature of 150 °C; while silicon carbide (SiC) based electronics have the theoretical potential to operate at junction temperatures in excess of 600 °C. Such extended temperature limits would allow for highly integrated power electronics systems with very light-weight and power dense characteristics. SiC can block 10× more voltage than silicon, has a higher current density, can transition between the on and off states 10× faster than silicon, and has a lower on-resistance (i.e. is more energy efficient).

Since its founding, APEI has spent considerable time and effort characterizing various types of SiC devices. Complete understanding of the operation of these devices is crucial in order to properly incorporate them into a power electronic system. The potential for high temperature operation allows APEI designers to treat temperature not as a limiting constraint, but as a design variable. The advantage of this high temperature operation capability is two-fold: (1) it allows for the power modules to operate efficiently and reliably in high temperature ambient environments (such as under the hood of a hybrid-electric vehicle or in the wing of an aircraft) and (2) it allows for a significantly smaller and lighter power electronics system through the reduction of the thermal management system.

Silicon Carbide Devices