All the World's a Stage ... for Wide-Bandgap Semiconductors

Jason Lomberg, North American Editor, PSD



We’ve passed the one-year anniversary of the COVID-19 outbreak, and while vaccines slowly disperse around the globe, it’s business as kinda-sorta-usual in power electronics. And this month, we’ve landed on one of our favorite topics – wide-bandgap semiconductors.

It used to be that I couldn’t turn my head at a trade show without locking eyes with something wide-bandgap related. These days, I can’t open an email or hold a Zoom conference without at least a peripheral GaN or SiC application.

And to lead off our wide-bandgap issue, I’d highly recommend you check out our PSDcast with our old friends at GaN Systems. Their Director of Business Development, Julian Styles, predicts a huge year for GaN chargers – 2020 saw the first compact, efficient GaN chargers, and then other companies immediately jumped on the bandwagon. It doesn’t hurt that GaN chargers are intrinsically smaller than silicon chargers.

The last year mainly produced GaN accessory chargers, and 2021 could see them proliferate into a broader array of applications, like medical, industrial, and gaming.

Meanwhile, the first article I’d like to highlight discusses “Redefining Power Conversion with Gallium Nitride (GaN) Integrated Circuits.”

Efficient Power Conversion’s Alex Lidow delves into one of GaN’s key strengths – its ability to integrate multiple devices on the same substrate.

“This capability will allow monolithic power systems to be designed on a single chip in a more straightforward, higher efficiency, and more cost-effective way,” he says.

You can probably guess which angle UnitedSiC approaches wide-bandgap devices (hint: It’s in their name), but they do so in novel fashion with “Silver Sintering Improves Thermal Conductivity in Power Semiconductors.”

Longtime contributor Anup Bhalla – who you might remember from “Impact of UnitedSiC Gen 4 Technology on Electric Vehicles” and “Efficient WBG Power for Medium Voltage Applications” – notes that “minimizing the thermal resistance from die to case and ambient is key.”

And because silver sintering reduces thermal resistance, the process improves RθJC and, thanks to its higher melting point, also adds thermal margin to the overall design. Choosing silicon carbide, says Bhalla, retains the performance and cost advantages of a smaller die area while minimizing the disadvantages.

Finally, I want to call-out the Wolfspeed piece, “Modeling Common Topologies with Silicon Carbide MOSFETs,” by Guy Moxey.

While SiC and Si share basic design principles, it’s important to use standard modeling mitigations to achieve SiC’s inherent advantages and help engineers reach their design goals.

Because SiC isn’t going anywhere.

“Now more than ever,” says Guy, “engineers are choosing Silicon Carbide (SiC)-based products for their higher efficiency, power density, and better overall system cost effectiveness.”

Enjoy the March issue!

Best Regards,

Jason Lomberg

North American Editor, PSD