April 2018 - Silicon Carbide (SiC) is a Popular Choice for Power Electronic Devices
Published on: 12/04/2018
As more engineers choose to use silicon carbide, we look at the benefits SiC has to offer
Silicon has been used as a semiconductor switch for over 50 years and the quest for higher switching frequencies, higher blocking voltages, lower losses, greater power densities and increased operating temperatures has led to the launch of Silicon Carbide (SiC) and other wide band gap materials used in power devices.
Silicon Carbide is fast becoming more widely used in power semiconductors because silicon based devices have almost reached their maximum theoretical performance. Silicon Carbide is considered a Wide Band Gap (WBG) Material which defines the difference in energy levels between the material’s conduction and valence boards.
The diagram featured below shows the filled bands which refer to the electrons occupying the regions and the holes are evident in the unfilled regions. When you apply external energy in the form of heat or light, electrons are excited to jump the band gap into the conduction band and the current is allowed to flow.
Wide Band Gap
The wider band gap leads to a higher critical electrical field (approximately 10 times greater than Silicon) improving breakdown voltages and enabling higher blocking voltages for power devices Silicon Carbides are a cost effective alternative, they are able to switch much faster than Silicon with lower losses. This enables passive and magnetic components to be downsized in design, leading to greater power density for the converter.
What Type of SiC Devices are Available?
For many years, Wind Band Gap materials such as SiC and GaN have been used in light emitting devices with the first practical launch of SiC power devices being the Schottky Barrier Diode (SBD) which was introduced in the nineties. Since then numerous other SiC power devices have been released, these include: rectifier diodes, MOSFETs, JFETs, BJTs and thyristors.
GD Rectifiers is Europe’s leading official distributor for SEMIKRON products, including: SiC Hybrid range (Si IGBT and SiC SBD) and the full SiC range (SiC MOS and SiC SBD’s) power modules. The modules are available in SEMIKRON’s popular packages including: SEMITRANS3, MiniSKiiP, SEMITOP, SEMIPACK2, SKiM93 and SEMiX3P.