New material that cuts down on phone chargers, powers electric cars, and makes 5G possible

A byproduct of extracting aluminum from rock, gallium has such a low melting temperature that it turns into a silvery-white liquid that flows when you hold it in your hand. In itself, it is not very useful. Combine it with nitrogen, to make gallium nitride, and it becomes a hard crystal with valuable properties. It appears in the laser sensors used in many self-driving cars, the antennas that enable today’s fast cellular wireless networks and, increasingly, in essential electronics for making renewable energy harvesting more efficient. .

Many of the more tangible things made possible by gallium nitride, also known as GaN, are happening in power electronics. Today you can buy small USB-C chargers with enough power to power your laptop, phone and tablet simultaneously, although they are no bigger than the much less powerful versions that have accompanied our gadgets since. years.

Power electronics that convert one voltage level to another are also essential to many aspects of electric vehicles. They’re smaller, lighter, more efficient, and emit less heat, so EVs can travel farther on a charge, says Jim Witham, general manager of chipmaker GaN Systems. These properties are also excellent for extracting much more electricity from renewable energy sources such as solar panels, he adds. Even small efficiency gains in converting electricity add up when they occur multiple times, such as in a renewable energy grid that includes battery storage.

A miracle material that GaN is, it faces competition from proven silicon and a growing list of new materials that show the potential to revolutionize our electronics. However, its uses are increasing. GaN Systems also has customers who test its chips in data centers, where reduced power consumption and waste heat can translate into massive savings on electricity bills. None of its data center customers have publicly acknowledged using this technology.

There was a time, not so long ago, that GaN was just a laboratory curiosity. Then, the Pentagon became interested in researching new types of electronics to control new generation radars and wireless communications. Starting around 2000, funding from Darpa, the Defense Ministry’s advanced research agency, conducted the experiments necessary to overcome many obstacles to its commercialization, says Rachel Oliver, professor of materials science and director of the Department of Defense. Center for Gallium Nitride at the University of Cambridge.

Along with its myriad of applications in the civilian world, GaN is now appearing in military hardware used for everything from radio jamming to missile defense, all made possible by its unique properties.

Unlike silicon, GaN can handle relatively large amounts of electricity. It has the unusual property of being both very good at moving electrons and very good at not allowing them to go where you wouldn’t want them to be, which makes it both useful and relatively safe. says Dr. Oliver.

In addition to its talent for conducting electricity, it is GaN’s ability to operate at much higher frequencies than possible with silicon – between 30 and 500 times faster in commercial applications – that allow much larger chargers. small or provide more power than traditional chargers.

As our entire world becomes increasingly electrified, from our energy sources to the devices that use it, anything that performs the critical but easily overlooked function of converting electricity from one form to another more efficiently. has the potential to become both ubiquitous and a huge source of income. That’s why there are dozens of startups and companies established in this space, including Navitas Semiconductor, GaN Systems, Power Integrations, Texas Instruments, Infineon, and STMicroelectronics.

The GaN power electronics market, however, is still fairly nascent. In 2019, the overall market for all transistors was around $ 16 billion, while the market for the type offered by Navitas, GaN Systems and others was $ 45 million, said George Brocklehurst, vice -President of research at Gartner.

There are other potentially revolutionary materials that are starting to compete with silicon, such as graphene, but GaN microchips have the huge advantage that they can be produced in the same type of manufacturing facilities – called factories – that make conventional microchips. , explains Stephen Oliver, Marketing Director at Navitas.

Because they don’t require the most advanced chip manufacturing technology, GaN chips can be produced in older, premium factories that might otherwise be idle. A happy side effect has been that the supply of GaN chips has not been caught up by the wider global semiconductor shortage, says Oliver. Navitas chips are currently manufactured in the oldest factory still operated by TSMC, the Taiwanese titan of chipmaking.

The adoption of GaN is now so widespread that prices are falling rapidly. That’s why you can now buy a GaN charger for $ 20 to $ 70 which is better in every way than the ones that came with your gadgets.

Companies like GaN Systems are pushing technology into other areas. BMW and Toyota are both investors in GaN Systems. In 2019, Toyota presented a prototype vehicle with fully GaN-based power electronics, from the car’s on-board charger to its LED lights.

That said, GaN chips aren’t a slam-dunk winner. Advances in materials science have generated a handful of competitors. Traditional silicon power electronics are still dominant in most applications, and in the automotive world, silicon carbide, an alternative with many of the same properties as GaN, has a much longer track record, explains Mr. Gartner’s Brocklehurst.

A range of promising but less well understood substances could make all of the previously mentioned good value for money, including gallium oxide and aluminum oxide. Both are semiconductors that can be turned into microchips, says Dr Oliver.

Where the hardware revolution hasn’t taken root is in the biggest semiconductor market: the processors that power our computers. Until recently, says Dr Oliver, GaN only did half of the things a traditional silicon transistor can do.

Until now, GaN cannot handle the flow of electric current required to perform the type of calculations performed by traditional silicon logic chips. But recent findings suggest that may change.

“If you had asked me a few years ago if we would see GaN for logic, I would say, ‘Oh, don’t be stupid,’” she said. “But now it’s possible and it can lead to faster devices. “

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Write to Christopher Mims at [email protected]