Can Wide-Bandgap Devices Help Lead to a Carbon-Neutral Future?

December 31, 2020 by Jake Hertz

STMicroelectronics announced a goal to be carbon neutral by 2027, and they plan to get there by using wide-bandgap semiconductors. How might this technology bring the industry toward carbon neutrality?

The goal of carbon neutrality is becoming increasingly popular among technology companies. Google has been a pioneer in this effort, achieving zero carbon emissions in 2007 and claiming to have erased its entire carbon legacy as of 2017.

Many semiconductor companies have since committed themselves to this altruistic goal with Infineon aiming for neutrality by 2030 and NXP aiming to decrease yearly emissions by 30%


NXP's scope of emissions

NXP's scope of emissions. Image used courtesy of NXP

STMicroelectronics Joins the "Green" Effort 

Now, STMicroelectronics has joined the movement, announcing last week that they will be teaming up with Schneider Electric with the goal of achieving carbon neutrality by 2027. 


Converter power vs. switching frequency

Converter power vs. switching frequency. The red line depicts the limits of silicon while the dotted line indicates the performance possibilities of WBG semiconductors. Image used courtesy of ARPA

Leveraging Schneider’s automation expertise, ST hopes to reduce the overall energy consumption of their manufacturing and design sites as well as implement renewable energy sources in their locations. Beyond this, the two have announced that as part of their collaboration, they will work to bring energy efficiency to buildings, data centers, and infrastructure in general. 

One of the major tenets of this plan will be to invest in wide-bandgap (WBG) semiconductors such as SiC and GaN. 


WBG Semiconductors and Carbon Neutrality 

Wide-bandgap semiconductors are semiconductor materials that have a higher valence-band-to-conduction-band energy gap than silicon. The result of this property is that WBG semiconductors can operate significantly more efficiently at higher temperatures and higher voltages than silicon. 

With respect to carbon neutrality, an important benefit of WBGs is that they offer improved energy efficiency of power conversion. It has been shown that WBGs can provide up to 10% higher power conversion efficiency than their silicon counterparts, which can make a significant difference in high power applications like vehicles and data centers.


GaN and SiC efficiencies vs. output power and temperature

GaN and SiC efficiencies vs. output power and temperature. Screenshot from GaN Systems

Further, the ability to operate efficiently at high temperatures also proves to be hugely important. Compared to silicon, WGBs can be used at higher temperatures, but more importantly, they also need less cooling resources.

Considering the fact that up to 55% of a data center’s entire energy expenditure can be spent on cooling, it's clear to see why WBGs have such a pull for eco-conscious companies.


Impacts on the Engineer 

As more and more companies start working toward carbon neutrality in the near future, it seems likely that investments into wide-bandgap semiconductors will only increase. As a practicing engineer, these developments may influence future design decisions. 

With more money being invested into developing WGBs, it is only a matter of time until these components are mature enough to be interchangeable with conventional silicon. For the sake of designing systems with better energy efficiency, it may be worthwhile to consider replacing silicon transistors with a WBG counterpart.