Silicon carbide is the senior citizen of WBGs, having been under development as a transistor material for decades. In that time, engineers have started using younger upstart WBG materials, like gallium nitride, or GaN. In the 1980s, researchers used gallium nitride to create the world’s first bright blue LEDs. Blue light comprises high-energy photons; gallium nitride, with its wide bandgap, was the first semiconductor that could practically produce photons with the sufficient energy. In 2014, three scientists were awarded the Nobel Prize in Physics for that innovation, which became ubiquitous in devices like TV screens and light bulbs.

Lately, researchers have started using gallium nitride to improve power electronics. The material reached commercial fruition over the past few years in adapters for charging phones and computers. These adapters are smaller, lighter, faster-charging and more efficient than traditional ones that use silicon transistors.

“A typical charger that you buy for your computer is 90 percent efficient,” said Jim Witham, chief executive of GaN Systems, a Canadian company that supplied the transistors in Apple’s gallium-nitride laptop chargers, which were released last fall. “Gallium nitride is 98 percent efficient. You can cut power losses by four times.”

Yole Développement estimates that the gallium-nitride market will grow to $2 billion in 2027 from its total of about $200 million this year.

Wide-bandgap materials are making their way into other applications as well. Data centers, large facilities filled with computer servers that run the online services we all depend on, are notorious users of electricity. Compuware, a supplier of high-end power supplies to data centers, says its gallium-nitride-based power supplies reduce wasted electricity by about 25 percent and take up 20 percent less space than conventional devices, allowing customers to run more servers in the same racks. The company also says that its gallium-nitride power supplies are being used in data centers run by major companies around the world.

Engineers are also working on using WBG materials to better take advantage of renewable energy sources. Solar cells and wind turbines rely on traction inverters to feed electricity into a home or into the grid, and many companies expect gallium nitride to do that job better than silicon. Enphase, a supplier of inverters for solar-powered installments, is currently testing gallium-nitride-based inverters to make sure they can hold up to harsh rooftop weather conditions for decades. In one test, Enphase submerges inverters underwater inside a pressure cooker, puts the pressure cooker inside a sealed chamber and oscillates the temperature between 185 degrees and minus 40 degrees Fahrenheit over the course of 21 days. If gallium-nitride devices survive the challenges, Enphase’s co-founder Raghu Belur plans to make a fast shift to the new material. “It’s absolutely headed in that direction,” he said.

In an investors’ meeting last year, a senior Enphase engineer gave a more conclusive prediction, saying, “It’s the end of the road for silicon.”

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