Many of us who have been in the industry awhile remember discussing whether digital control of power electronics would ever be adopted – at a time when almost all variable speed motor drives were already digitally controlled. Now, that digitally controlled power electronics have been, for the most part, mainstreamed, we’re having similar adoption discussions about wide bandgap (WBG) silicon carbide (SiC) and gallium nitride (GaN).
There is little doubt that WBG device adoption is growing but it’s still a small percentage of the total power semiconductor market. I recently saw a supplier of WBG semiconductors citing that they had sold several million devices. This is great news until you consider that somewhere over 80 billion silicon MOSFETs were sold in 2019 – so let’s just say that the market for WBG has room for growth.
The Rise of WBG
In the world of wide bandgap, silicon carbide got its start as a semiconductor material used in lighting applications and, later, RF power amplifiers. As a result, we in the power electronics industry were beneficiaries of technology that was actually mainstreamed in other market areas before it got to us. The same is true for GaN. The driver for GaN was lighting and then RF power amplifiers, including microwave applications in the military and aerospace market. In other words, the R&D, ARPA, DARPA and funding from other markets helpfully paved the way for us in the cost-constrained power electronics market to use GaN technologies in our applications.
Today, the electrification of transportation and the need for high-temperature, high-reliability semiconductors – and the more nearly perfect switch – has driven both silicon carbide diodes, and now silicon carbide MOSFETs, to be increasingly used in automotive applications. These include motor drive, battery management and battery charging applications, such as battery charging stations external to the vehicle.
With more electronics content in the vehicle there is more room for applications that need, or work best with, silicon carbide. It’s no longer a solution looking for a problem – the problems it solves are proximate. And while silicon carbide has been quietly growing, the GaN switch business also has been moving along nicely. As with SiC technology,
Future Growth
While wide bandgap SiC semiconductors are finding their way in our industry, and it is my belief that the automotive market, especially LIDAR and other fast switching applications, are setting the stage for adoption in other market areas. For instance, wide bandgap parts, both GaN and SiC, that can pass the automotive AEC-Q standard and meet other stringent quality and price pressures that enable them to work, and last, in automotive applications, will obviously be valuable for applications in industrial markets.
Today, interestingly enough, high-performance professional grade audio applications, such as class D audio amplifiers, are discovering that GaN technologies are exceptional performers in high-power high-fidelity applications. Therefore, what we can say, is that range of applications continues to expand for both SiC and GaN. And while parts continue to rapidly mainstream in power electronics, there is also huge growth potential in our industry.
PSD
