Silicon Carbide Detectors for Radiation Applications

Silicon carbide (SiC) has emerged as a premier wide-bandgap semiconductor for radiation detection, combining exceptional chemical inertness, high thermal conductivity and intrinsic radiation hardness. Devices based on 4H-SiC and 6H-SiC polytypes exploit the material’s wide energy gap to operate at room temperature with low dark current and minimal noise. Both Schottky barrier diodes and PiN junctions have been engineered to detect charged particles, neutrons and photons across a broad energy spectrum. Key advantages include high electric-field tolerance, rapid charge collection and stability under intense irradiation. Progress in bulk crystal growth and epitaxial layer deposition has reduced defect densities, while advances in doping and contact fabrication have yielded detectors with energy resolutions rival- ling or surpassing those of silicon at ambient conditions. These attributes position SiC detectors for applications in nuclear fusion monitoring, medical imaging, space missions and security screening, where reliability in harsh environments is paramount.

Research from Nature Portfolio

Recent investigations have correlated electrically stimulated photon emission with shifts in threshold voltage in fully processed 4H-SiC power transistors, revealing a direct optical signature of interface defect levels. By etching back devices to gain optical access, researchers have mapped defect transition energies, offering new pathways to refine passivation and enhance charge-collection uniformity in detection architectures. Equally, studies of 4H-SiC Schottky diodes exposed to deuterium–tritium fusion neutrons have demonstrated that these devices sustain fluences up to 7 × 10^14 n/cm^2 with only moderate increases in leakage current and a retention of over 75 % charge collection efficiency at 300 V bias. Such results underscore the resilience of SiC detectors in extreme neutron-rich environments and highlight their superiority over conventional silicon under comparable exposure conditions.

Silicon Carbide Detectors for Radiation Applications publication trend

The graph below shows the total number of articles in silicon carbide detectors for radiation applications across all publications each year (not limited to Nature Index journals).

Technical terms

Wide-bandgap semiconductor: A material with a large energy gap between valence and conduction bands, enabling high-temperature and high-field operation.

Schottky barrier diode (SBD): A metal–semiconductor junction device used for radiation detection, offering fast response and low noise.

Charge collection efficiency (CCE): The fraction of generated charge carriers that are successfully collected by the electrodes.

Carrier lifetime (τ): The average time that charge carriers persist before recombining, influencing detector signal strength.

Epitaxial layer: A crystalline semiconductor film grown atop a substrate, with controlled thickness and doping for detector fabrication.

Damage coefficient: A parameter describing the rate at which carrier lifetime degrades per unit radiation fluence, often temperature dependent.

References

1. Electrically stimulated optical spectroscopy of interface defects in wide-bandgap field-effect transistors. Communications Engineering (2023).
2. Carrier Lifetime Dependence on Temperature and Proton Irradiation in 4H-SiC Device: An Experimental Law. IEEE Access (2024).
3. SiC detectors: A review on the use of silicon carbide as radiation detection material. Frontiers in Physics (2022).
4. Radiation Resistance of Silicon Carbide Schottky Diode Detectors in D-T Fusion Neutron Detection. Scientific Reports (2017).
5. Silicon carbide neutron detector testing at the JSI TRIGA reactor for enhanced border and port security. Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment (2020).