News Article

GaN Nanowire Transistor Keeps Its Cool At High Voltages


EPFL team's design can support high electric fields, and voltages of over 1,000V without breaking down

Engineers at the École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland (EPFL) have come up with a GaN nanowire-based new high efficiency power transistor for high voltage applications. The published their findings in Nature Electronics.

The heat dissipation in converters is caused by the high electrical resistance, among other factors, which is the biggest challenge in power electronic devices. "We see examples of electric power losses every day, such as when the charger of your laptop heats up," says Elison Matioli, a coauthor of the paper and head of EPFL's POWERlab.

This becomes even more of a problem in high-power applications. "The higher the nominal voltage of semiconductor components, the greater the resistance," he adds. Power losses shorten the ranges of electric vehicles, for instance, and reduce the efficiency of renewable-energy systems.

Matioli, along with his PhD student Luca Nela and their team, have developed a transistor that can substantially reduce the resistance and cut the amount of heat dissipation in high-power systems. More specifically, it has less than half as much resistance as conventional transistors, while holding voltages of over 1,000 V.

The EPFL technology incorporates two key innovations.

The first involves building several conductive channels into the component so as to distribute the flow of current - much like new lanes that are added to a highway to allow traffic to flow more smoothly and prevent traffic jams. "Our multi-channel design splits up the flow of current, reducing the resistance and overheating," says Nela.

The second innovation involves using GaN nanowires. The POWERlab demonstrated nanowires with a diameter of 15 nm and a unique funnel-like structure enabling them to support high electric fields, and voltages of over 1,000 V without breaking down.

Thanks to the combination of these two innovations - the multi-channel design that allows more electrons to flow, and the funnel structure that enhances the nanowires' resistance - the transistors can provide greater conversion efficiencies in high-power systems. "The prototype we built using slanted nanowires performs twice as well as the best GaN power devices in the literature," says Matioli.

While the engineers' technology is still in the experimental phase, there shouldn't be any major obstacles to large-scale production. "Adding more channels is a fairly trivial matter, and the diameter of our nanowires is twice as big as the small transistors made by Intel," says Matioli.The team has filed several patents for their invention.

'Multi-channel nanowire devices for efficient power conversion' by L. Nela et al; Nature Electronics (2021)

AngelTech Live III: Join us on 12 April 2021!

AngelTech Live III will be broadcast on 12 April 2021, 10am BST, rebroadcast on 14 April (10am CTT) and 16 April (10am PST) and will feature online versions of the market-leading physical events: CS International and PIC International PLUS a brand new Silicon Semiconductor International Track!

Thanks to the great diversity of the semiconductor industry, we are always chasing new markets and developing a range of exciting technologies.

2021 is no different. Over the last few months interest in deep-UV LEDs has rocketed, due to its capability to disinfect and sanitise areas and combat Covid-19. We shall consider a roadmap for this device, along with technologies for boosting its output.

We shall also look at microLEDs, a display with many wonderful attributes, identifying processes for handling the mass transfer of tiny emitters that hold the key to commercialisation of this technology.

We shall also discuss electrification of transportation, underpinned by wide bandgap power electronics and supported by blue lasers that are ideal for processing copper.

Additional areas we will cover include the development of GaN ICs, to improve the reach of power electronics; the great strides that have been made with gallium oxide; and a look at new materials, such as cubic GaN and AlScN.

Having attracted 1500 delegates over the last 2 online summits, the 3rd event promises to be even bigger and better – with 3 interactive sessions over 1 day and will once again prove to be a key event across the semiconductor and photonic integrated circuits calendar.

So make sure you sign up today and discover the latest cutting edge developments across the compound semiconductor and integrated photonics value chain.



Search the news archive

To close this popup you can press escape or click the close icon.
Register - Step 1

You may choose to subscribe to the Compound Semiconductor Magazine, the Compound Semiconductor Newsletter, or both. You may also request additional information if required, before submitting your application.

Please subscribe me to:


You chose the industry type of "Other"

Please enter the industry that you work in:
Please enter the industry that you work in:
Live Event