Fusion reactors present a particularly harsh setting: the first wall—shielding the fuel—degrades under intense radiation. Engineers currently monitor damage indirectly because silicon-based sensors cannot survive long enough inside the barrier, often requiring costly shutdowns for inspection.

After irradiation, the GNR devices still responded electrically, even though their performance changed dramatically. That combination—survival plus a clear, measurable output shift—is exactly what a radiation sensor must deliver to enable more reliable, condition-based maintenance planning.

The study connects the electrical response to atomic-scale effects. Measurements suggest that gamma exposure leaves the nanoribbon’s overall framework intact while altering the ribbon edges through radiation-driven reactive molecules in the surrounding air. Because transport in such narrow structures is governed by quantum rules, even subtle edge modifications can produce outsized changes in current flow.

The researchers propose that the signal arises from Anderson localization, a quantum phenomenon in which electrons become trapped by disorder. In this scenario, irradiation-induced changes reduce charge transport sharply, turning the nanoribbon into a sensitive indicator of radiation exposure.

Beyond fusion, the implications extend to space systems. Satellites, Earth-observation missions, and deep-space probes all face long-duration radiation environments where early detection of radiation-related wear could prevent failures before they occur.

To achieve the required precision, the team synthesized GNRs from the molecular level and embedded them in standard semiconductor device platforms. The ribbons were fabricated to be about one atom thick and roughly 45 nanometers long, producing a structure thin enough for quantum effects to dominate behavior.

Future work will test a range of gamma doses and fabricate GNRs of different sizes. The researchers also emphasize that the fabrication approach is designed to allow atom-by-atom tailoring of sensitivity, enabling radiation systems that can be engineered to respond—or not respond—within specific regimes.

Keywords

Graphene nanoribbons, gamma radiation, semiconductor devices, quantum transport, Anderson localization, radiation sensing, fusion energy, space electronics

Subject of Research: Graphene nanoribbons as radiation-sensing elements
Article Title: Electrical and Structural Response of Nine-Atom-Wide Armchair Graphene Nanoribbon Transistors to Gamma Irradiation
News Publication Date: 20-Apr-2026
Web References: http://dx.doi.org/10.1021/acsami.6c02516
References: 10.1021/acsami.6c02516
Image Credits: Photo by Leslie Hawthorne Klingler, University of Arizona Office of Research and Partnerships

SiC power semiconductors are gaining traction in various applications due to their exceptional performance characteristics. Unlike traditional silicon (Si) semiconductors, SiC devices are capable of withstanding much higher voltages and temperatures, making them especially valuable in applications where efficiency and performance are paramount. While silicon has traditionally dominated the semiconductor market, the superior attributes of SiC, including their ability to operate in environments with extreme conditions, are creating a paradigm shift in the industry. These materials have the potential to revolutionize sectors such as aerospace, automotive, and energy production.

Fundamentally, power semiconductors act as the "muscles" within electrical devices, enabling control over current flow and power conversion. As the demand for increased efficiency and reliability in these applications rises, the exploration of wide bandgap (WBG) semiconductors, such as SiC and gallium nitride (GaN), has intensified. With their broader bandgap, SiC semiconductors not only outperform silicon in terms of efficiency but also deliver significant advantages in power handling, reliability, and operational longevity—key factors for the demanding conditions of space.

However, the challenges posed by space radiation represent a significant obstacle. High-energy particles bombard electronics in space, leading to degradation of material properties and functionality over time. This phenomenon has been a considerable concern for satellites, spacecraft, and various exploration vehicles, where maintaining operational integrity is critical. Although there has been substantial research in radiation effects in the United States and Europe, Korea’s previous academic focus has been rather limited to the quantitative aspects associated with silicon-based devices.

In a pioneering effort, Dr. Seo’s research team incorporated Korea’s first high-energy space environment simulation to assess the radiation resistance of SiC power semiconductors. To create an authentic simulation of space conditions, the researchers needed to understand the unique characteristics of space radiation, primarily consisting of protons (80–90% of the particles). By utilizing high-energy protons sourced from the accelerator facility at the Korea Atomic Energy Research Institute, and in partnership with experts from Andong National University, they meticulously recreated precise radiation exposure conditions to study the effects on the semiconductors.

Throughout the experimental process, KERI’s researchers collected data on several crucial metrics, including voltage fluctuations, increases in leakage current, and lattice damage due to exposure. These factors are essential for creating precise design criteria, aimed at ensuring the long-term reliability of SiC power semiconductor devices in space applications. The outcomes of this rigorous study were commended with a publication in the prestigious journal Radiation Physics and Chemistry, which highlights the significance of their achievement within the scientific community.

Dr. Seo emphasized the importance of establishing various radiation effect parameters and simulating them effectively. According to him, such capabilities represent a vital technology within the global space industry, underscoring Korea’s commitment to advancing its capacity in aerospace technologies. He expressed optimism for the application of their research across several fields, ranging from aerospace to medical radiation equipment and even military electronics.

This research initiative aligns with KERI’s broader goals, which include undertaking comprehensive evaluations of SiC power semiconductors under severe radiation conditions. The research team’s aspirations extend beyond current capabilities as they aim to explore ultra-high energy radiation conditions exceeding 200MeV. Additionally, they are investigating the semiconductor properties of diamond, a material that offers the most favorable characteristics for high-performance applications. This exploration is facilitated through collaborations with both local entities, such as Gyeongnam Province, and international partners like the Japanese company ‘Orbray’.

The implications of these research endeavors will resonate throughout Korea’s high-value-added aerospace industry. By developing reliable SiC power semiconductors capable of thriving in extreme radiation environments, researchers are paving the way for the next generation of space exploration vehicles and systems designed to withstand the rigors of space radiation. Such advancements could help maintain the integrity of power electronics in future missions, ensuring that spacecraft and satellites operate efficiently over extended lifespans.

As Korea continues to invest in semiconductor research and innovation, the potential benefits of this work extend beyond national interests. There is a growing recognition that the advancements made here could influence global markets and international collaborations, moving towards a future where semiconductor technologies can drive breakthroughs in various sectors.

In conclusion, Dr. Jae Hwa Seo and his team at KERI are not just conducting focused research on SiC semiconductors, but are contributing to a larger narrative surrounding the essential role of advanced materials in modern civilization. Their work highlights the intricate relationship between technology and the extreme environments encountered in space, illustrating the complex challenges and solutions that researchers face in the quest for broader, more reliable applications in cutting-edge technology.

Subject of Research: Radiation Resistance of SiC Power Semiconductor Devices in Space Environments
Article Title: Degeneration mechanism of 30 MeV and 100 MeV proton irradiation effects on 1.2 kV SiC MOSFETs
News Publication Date: 1-Feb-2025
Web References: KERI Website
References: DOI link – 10.1016/j.radphyschem.2024.112378
Image Credits: Korea Electrotechnology Research Institute

Keywords

Silicon Carbide, Power Semiconductors, Space Radiation, Reliability, Technology Evaluation, High-energy Protons, Wide Bandgap Semiconductors, Aerospace Applications, Research Innovation, KERI.