STMicroelectronics Tackles the EV Industry with GaN
In an effort for cleaner and more efficient electric vehicles, STMicroelectronics is turning to GaN technology.
In high-power applications, like electric vehicles (EVs), power efficiency is vital. In many ways, silicon is not the best semiconductor material for these applications, and recent years have shown huge investment and investigation into other, wide-bandgap materials.
Applications of GaN and SiC based on voltages. Image used courtesy of Roccaforte et al
Of these materials, gallium nitride (GaN) has proven to be a top contender and has made its way from academia into the industry and real-world applications.
Now, STMicroelectronics (STM) has put its money on GaN as well, releasing a new family of GaN devices meant specifically for the automotive industry.
Wide-Bandgap and GaN
Wide-bandgap semiconductors are made of materials that have a higher valence-band-to-conduction-band energy gap than silicon. These materials come with many benefits, like operating significantly more efficiently at higher temperatures and higher voltages than silicon.
A comparison of semiconductor material properties. Image used courtesy of STMicroelectronics
GaN specifically has proven to be one of the most popular wide-bandgap semiconductor materials, and for a good reason. The wide bandgap of GaN allows for designers to create semiconductors with very narrow depletion regions, which results in devices with very high carrier densities. The smaller sized transistors, along with shorter current paths, creates very low on-resistances, and capacitance is achieved, enabling switching speeds that can be up to 100x faster than silicon.
The combination of handling high electric fields and high temperatures while being significantly more power-efficient than silicon has made GaN an obvious choice for the automotive industry.
ST’s New Family
The newest GaN offering from STMicroelectronics is their STi2GaN, standing for “intelligent and integrated” GaN.
This family, as the name implies, is very concerned with the integration of GaN devices. The STi2GaN family offers devices that combine a monolithic power stage along with drivers and protections in GaN and SiP solutions for ASICs.
STMicroelectronics sees their GaN being used in everything from EV to audio. Image used courtesy of STMicroelectronics
While many technical specs are not released, STMicroelectronics claims to have taken GaN one step further by introducing their proprietary bond-wire-free packaging. By packaging the devices without the need for bond wires, STM claims to have significantly reduced parasitics from packaging, resulting in decreased EMI and loss and allowing for double-side cooling, allowing for better thermal dissipation.
STM’s move towards wide-bandgap semiconductors does not come as a surprise. A few months back, AAC covered a related development from STM where the company announced it was teaming up with Schneider Electric to achieve carbon neutrality by 2027. One of the corollaries of this partnership was that STM was planning to invest heavily in wide-bandgap (WBG) semiconductors such as SiC and GaN.
Now, about five months later, this investment is starting to come to fruition.
If their adherence to their goals is to this point is any indication, you could expect to see more wide-bandgap devices, such as GaN and SiC, coming out of STMicroelectronics in the coming years.
Interested in learning more about recent GaN advancements and integrations? Find out more by reading down below.