Researchers from King Abdullah University of Science and Technology (KAUST)in Saudi Arabia, developed electronic devices capable of operating stably in a temperature range that no conventional semiconductor can withstand: from almost absolute zero, to 2 K (-271.1 °C), up to 500 °C.
For comparison purposes, any electronic component present in a common computer or smartphone is probably would stop working before reaching 200°C. At low temperatures, collapse usually occurs around -173 °C.
The achievement, announced in a university press release this week, is the result of work led by Vishal Khandelwalformer doctorate in the professor’s laboratory Xiaohang Liand represents the first successful use of an ultrawide bandgap semiconductor in logic transistors and inverters capable of operating in such extreme conditions.
The material behind the feat is the Beta Gallium Oxide (β-Ga₂O₃)an unusual semiconductor that the team adapted with a specific doping technique to resist both ends of the thermal spectrum.
Why conventional chips fail in cold and heat
To understand progress, you need to understand the Silicon limits: Electrical conduction in semiconductors depends on electrons having enough energy to migrate to the so-called conduction band, where they can move freely through the material and generate electrical current.
At very low temperatures, these electrons lose thermal energy and become trapped, unable to make this jump. The phenomenon, known as “carrier freezing” (carrier freeze-out), makes the operation of conventional chips below approximately 100 K (-173 °C).
At the opposite extreme, excess heat also poses a problem. When temperatures rise, electrons gain too much energy and begin to invade the conduction band in an uncontrolled manner, even when the device should be in the “off” state.
That causes electrical leakage, instability in logical switches, overheating and, finally, total component failure. Electronic systems used in extreme environments, such as space probes and quantum computing equipment, need to work around these limitations with specialized electronics and complex and expensive thermal management systems.
The Gallium Oxide difference
THE β-Ga₂O₃ it has an ultra-wide bandgap, which means there is a much higher energy barrier between electrons at rest and the conduction band. With this high barrier, the material naturally resists unwanted excitations caused by heat, making it much more stable at high temperatures.
It is this characteristic that gives Gallium Oxide resistance to thermal instability up to 500 °C, as well as greater tolerance to electrical breakdown failures in extreme conditions.
Materials like Gallium Nitride (GaN) and Silicon Carbide (SiC)already used in high-performance applications, offer advances in relation to standard Silicon, but still fall short of what β-Ga₂O₃ can provide in terms of bandgap.
The material’s ability to grow into high-quality films with lower-cost techniques is also seen as a practical advantage for future industrial applications.
The solution to extreme cold: Silicon doping
Heat resistance naturally comes from the properties of Gallium Oxide, but dealing with extreme cold required a different strategy.
To circumvent the freezing of carriers at cryogenic temperatures, researchers performed a heavy doping with Silicon atoms. In the semiconductor engineering environment, doping a material means intentionally introducing atomic impurities to alter its electrical behavior.
By inserting a high concentration of Silicon dopants, the team created conditions in which electrons can move by jumping between very close electronic states associated with Silicon impurities, without needing thermal energy to reach the main conduction band.
The alternative conduction mechanism, called the “impurity band”, maintains electrical flow even at temperatures at which any conventional semiconductor would have already stopped working.
“At that temperature, there is virtually no thermal energy to help the electrons jump into the Gallium Oxide’s conduction band. Instead, the electrons hop through an ‘impurity band’ created by the Silicon atoms, allowing the device to conduct current.”
Xiaohang Liprofessor at KAUST
Two devices, one historic demonstration
With the material prepared for both thermal extremes, the team built two devices based on β-Ga₂O₃ doped with Silicon.
The first was a FinFET (Fin Field Effect Transistor)a fin-shaped channel architecture that offers greater electrostatic control and stability compared to conventional planar transistors.
The second was a logic inverteralso called NOT gate, a fundamental block in digital circuits that inverts the input signal in order to process information.
Both components have been tested at temperatures as low as 2K (-271.1°C)and both performed reliably.
This is a relevant milestone: although there are electronic devices capable of operating at ultra-low temperatures, no previous demonstration had used an ultra-wide bandgap semiconductor in transistors and logic inverters operating at temperatures so close to absolute zero.
The path to complex cryogenic chips
The research team sees the current results as building blocks for a broader generation of devices resistant to extreme temperatures.
The plan is to expand the portfolio of β-Ga₂O₃-based components, including radio frequency transistors, photodetectors and memory cellsall compatible with extreme temperature environments.
“We’ve demonstrated the basic building blocks; now the work is to scale this up to complex cryogenic chips and push the limits of performance in this ultracold regime.”
The natural progression of this work would point to integrated circuits with dozens or hundreds of components, operating in a coordinated way in environments where Silicon simply does not work.
Applications: from deep space to quantum
Gallium Oxide-based electronics would be extremely valuable for space probes, satellites and other systems exposed to the brutal thermal variations of spacewhere temperatures can drop to close to absolute zero on the shadow side and rise dramatically when exposed to solar radiation.
Another promising application is in quantum computing. Quantum systems generally operate at cryogenic temperatures, and electronic control circuits need to operate under these same conditions. This currently requires specialized electronics and sophisticated thermal insulation systems.
Chips based on β-Ga₂O₃ could substantially simplify this infrastructure, reducing costs and the physical size of the equipment.
β-Ga₂O₃ as a 21st century semiconductor platform
KAUST’s research is part of a global trend towards semiconductor materials capable of going beyond the physical limits of Silicon.
THE β-Ga₂O₃ jIt has aroused interest due to its tolerance to high voltages, low electrical losses and ease of growth on a substrate, but the ability to operate in both extreme heat and absolute cold opens up a new dimension for the material: that of a universal platform for electronics in hostile environments.
THE Gallium Oxide It does not replace Silicon in everyday applications, but it plays a role that no other semiconductor covers with such scope: ensure that electronics work where they have never worked before.
Sources): ACS Publications
Vishal Khandelwal et al., “Two Kelvin Operation of Ultrawide-Bandgap β-Ga₂O₃ FinFETs and Logic Inverter Integrated Circuits,” Nano Letters, ACS Publications, 2026.
Scientists create quantum material where electricity flows without generating heat for the first time.
Source: www.adrenaline.com.br
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