A collaborated team led by researchers from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences has successfully developed advanced semiconductor-based radiation detectors, significantly improving their performance for use in extreme environments.

The achievements have been published in IEEE Electron Device Letters and Nuclear Instruments and Methods in Physics Research A.

Radiation detectors act as the "eyes" for scientists, enabling the observation and study of nuclear radiation and microscopic particles. Traditional detectors, however, often struggle with low sensitivity and limited adaptability to extreme conditions, restricting their effectiveness in high-temperature and high-radiation environments.

In contrast, semiconductor-based detectors made from wide-bandgap and ultra-wide-bandgap materials offer several advantages, including higher temperature resistance, better radiation tolerance, and easier integration, making them promising for advancing radiation detection technology.

In this study, the team concentrated on optimizing the design, fabrication processes, and testing methodologies of semiconductor-based radiation detectors to address the shortcomings of existing technologies.

One of the team's major achievements was the development of large-area detectors made from a combination of p-NiO and β-Ga₂O₃ materials. These materials are known for their low leakage current and enhanced sensitivity. When coupled with specialized neutron detection materials, the team developed a thermal neutron detector made from Ga₂O₃, achieving nearly 1% efficiency in neutron detection—marking a significant milestone as the first successful experimental test of this technology.

In another project, the researchers engineered a highly sensitive detector using 4H-SiC, a material capable of withstanding extreme conditions. This detector operates with ultra-low doping levels and thick epitaxial layers, allowing it to accurately measure high-energy particles such as alpha particles. It also demonstrated stable operation at temperatures as high as 80°C for extended periods, which is crucial for studying superheavy elements in demanding environments.

To further improve the detector performance, the researchers developed a specialized annealing process to enhance the interface between the SiC material and its coating. This innovation resulted in an impressive improvement in energy resolution, allowing the detectors to achieve better than 0.5% resolution when detecting alpha particles.

Additionally, the team introduced a new type of thermal neutron detector that employs boron-based materials to boost neutron capture efficiency. This detector can distinguish between two key types of reactions involving thermal neutrons, representing another significant advancement in neutron detection technology.

These innovations signify substantial progress in the development of radiation detectors capable of operating effectively in extreme environments.

The optical microscope image and structural schematic diagram of the Ga₂O₃ detector. (Image by HAN Jingyun)

(a) Energy spectrum obtained with a ²²⁷Ac source and(b) linear response by 4H-SiC SBD devices. (Image by HAN Jingyun)

 Pulse height spectrum obtained by a 4H-SiC detector with NO annealing aftertreatment progress technique under irradiation of a ²³⁹Pu-²⁴¹Am hybrid source. (Image by HAN Jingyun)