What is SiC power module?

Today, the most widely used material for power semiconductors is silicon. Silicon is inexpensive to produce and the technology is well understood. However, there are other materials, the so called compound power semiconductors, such as silicon-carbide and gallium-nitride that are much more efficient conductors of electricity. This means that less energy is lost through heat in any power conversion process which has the added benefit of reducing the need to have expensive cooling systems as well as lowering the size and weight of the power electronics unit.

Learn more about what Silicon Carbide power modules are, how they work and why SiC is preferred in selected applications.

What is Silicon Carbide (SiC)?

Silicon carbide (SiC) is older than our solar system and was first discovered in meteorites dating back more than 4.6 billion years. But it is not until now that SiC has been industrialized to a point where it is now commercially and technically viable to compete with silicon in the production of power semiconductors.

Silicon carbide combines silicon (Si) and carbon (C) having unique electrical characteristics that allow to build high performance semiconductors for various applications.

What is a Silicon Carbide (SiC) power module?

A silicon carbide power module is a power module that uses a silicon carbide semiconductor as switches.  

A silicon carbide power module is used to transform electrical power, which is the product of current and voltage with high conversion efficiency.

Why are silicon carbide (SiC) power modules preferred for some applications?

Silicon carbide as a semiconductor has a wide band-gap, used in MOSFET it has very low switching losses and therefore allows higher switching frequencies compared to regular silicon devices. At the same time, it can be operated at higher temperatures and at higher voltages compared to traditional Si semiconductors.

The use of SiC power semiconductors is expected to grow exponentially due to its crucial efficiency characteristics that enables cost reductions while at the same time improving system performance in a variety of applications such as EV chargers, solar inverters, e-mobility, and motor drives.

Benefits of silicon carbide (SiC) power modules compared to today’s silicon (Si) devices

Compared to IGBT-based power module, SiC comes with several advantages: 

  • Faster switching meaning lower switching losses, less need for passive components and thereby reduced system footprint
  • Suitable for high switching frequencies
  • High blocking voltage 
  • Higher junction temperature
  • High current density meaning higher compactness and higher power density

Did you know?

To facilitate the growing demand for silicon carbide (SiC) power modules worldwide, Danfoss has established a “SiC Center of Excellence” in Munich, Germany containing offices and a 600m² lab. Besides qualification and development of semiconductors and different test scenarios, the new lab is also qualified and equipped for high power tests up to 400kW.

The purpose of the Danfoss’ SiC Excellence center is to support in the development of customized power modules and power stacks in a variety of customer projects, requiring SiC power modules. In addition, the SiC-team is also researching on future power module generations, including the fast switching SiC-semiconductors and their switching behavior.