High temperature transistors recorded a new record

This article is part of the exclusive Watch Journal in partnership with IEEE XPLORE.

There are two semiconductors – the Celon Celon and Nitrad Galium – they are competitors in a (literally) competition due to make the circuits able to perform at the highest temperatures. Silicon Caricoide chips have taken the initiative, which operates at 600 ° C, but gallium, which has unique features that make them more functional at high temperatures, now exceeded SIC. Researchers at Pennsylvania State University led by Ronging ChuProfessor of Electrical Engineering, designed the Nitrade Galium chip capable of It works at 800 ° C – Beware enough to dissolve the table salt.

Development may be very important for future space investigations, jet engines, pharmaceutical operations, and a group of other applications that need circles for maximum conditions. The high -temperature silicone temperature chips say to scientists by placing sensors in places that they have not been able to do before, he says Alan MantoothExcellent Professor of Electrical Engineering and Computer Science at Arkansas University, who did not participate in the new Nitrad Gallium result. He explains that the Nitrad Galium chip can do the same thing to monitor the health of natural gases turbines, intensive energy manufacturing processes in chemical factories and refineries, and the systems that no one has thought yet.

“We can put this type of electronics in places that you cannot even imagine,” he says.

Both silicon carbide and the potential of Nitrade Galium under these harsh conditions come from the wide range gaps. These are the energy gaps between the equivalence ranges in the materials, where the electrons are associated with the molecule and the scope of delivery, as it is free to contribute to the flow of electricity. At high temperatures, the electrons in materials with a narrower domain gap are always enthusiastic enough to reach the delivery range. This is a problem for transistors, because it will not be able to close. The wide range of domains of silicon and gallium carbide requires more energy to stimulate the electrons to the delivery range, so that the transistors are not always operated in high temperature environments.

Gallium Nitride also contains unique features compared to silicone carbide, which allows chips with better performance under high temperature conditions. IC for the Chu group, which they described this month in IEEE e -email messagesIt consists of the so -called high nitrid electron transistors. GAN Hemts’s brown includes an aluminum nitride film. The structure draws the electrons to the interface between the two articles.

This layer of electrons-called 2DEG (2DEG) electron-is very concentrated and moves with a little resistance. This means that shipping moves much faster in 2DEG, which leads to the transistor is able to respond to changes in effort and switch between countries outside and outside. The fastest electron movement also allows the transistor to carry more current in response to a specific effort. It is difficult to produce 2DEG using silicone carbide, which makes it difficult for its chips to match the performance of Nitrad Galium.

It shows that you persuade the GAN HEMT at the work at 800 ° C, which took some adjustments to its structure. Yixin XiongZhou graduate student. Some of these measures included reducing the leakage stream to a minimum, and sneaked somewhat even when the transistor is supposed to turn off. They did this using the Silby Tantalum barrier to protect the components of the device from the environment and by preventing the outer layer of the metal on both sides of the device from touching 2DEG, which may increase the leakage current and instability in the transistor.

Pennsylvania engineers have tested high -mobility in the electron at 800 ° C.The University of Ronging Chu/Pennsylvania State

Zhou says the search and manufacturing process was much faster than expected. The team was confident that the experience would work, he says. But he was “faster than my best,” he says.

Despite the noticeable benefits of its provision, the Mantooth is concerned about the long -term reliability of Nitride compared to silicone carbide. “One of the things that people were worried about with GAN in those extreme temperatures, 500 ℃ and above, is Microfractures or Microcracing [which is] “Not something we necessarily see in silicon carbide, so there may be reliable problems,” he explains.

Zhu agrees that long -term reliability is an area of improvement, saying, “There are some technical improvements that we can make: one makes it more reliable at a high temperature. At the present time, I think we can keep a price of 800 ℃ probably for one hour.”

Galium nitrid versus silicone carbide

Chiong says, there is still a lot of work to do to improve the device. He explains that unlike reducing the leakage stream, one of the Silby Tantalum barrier function is to prevent titanium in the device from a potentially reaction with Algan, which can destroy 2DEG. In the end, XionG wants to remove the titanium from the device completely. “The ultimate goal, as I say, is not to rely on titanium,” is concluded.

Despite the possible life challenges, the group’s chip pushes the limits of where the electronics can operate, as on the surface of Venus. “If you can keep it for one hour at 800 ℃, this means that in 600 or 700 ℃, you can keep it for a much longer period,” Zhu explains. The surrounding temperature is 470 ℃, so the new GAN record can be useful for electronics in the Venus probe.

Mantooth explains that the number 800 ℃ is also important for aircraft and high -sound weapons. Its maximum speeds generate friction that can heat the surface to 1500 ℃ Or more. “One of the things that many people do not realize is that when you fly in Mach 2, or Mach 3, the atmosphere creates an extreme environment on the front edge of the wing … and guess what is where your radar is located. This is where there are other processing equipment.

Regarding future plans, Zhou says the next steps are “expanding the device’s scope to make it work faster.” It is also believed that the slide may be ready for marketing is not very far from the line, because there are very few suppliers for chips who are able to work in such maximum temperatures. “I think he’s completely ready. It requires some improvements, but the beautiful thing in high heat electronics is that there is nothing else there,” he says.

However, the victory period of the Nitrad Galium circle may not last over its companions for a long time. The Mantooth laboratory also manufactures high temperature chips, and works to obtain silicone carbide to strike the Chu chips. “We will manufacture the circles to try to attack the same temperatures using silicone carbide,” says Mantooth. Although it is not clear who will finally end in the foreground, there is at least one thing, stressing: the competition is still heated.