Schottky-barrier semiconductor detectors for detecting alpha particles and neutrons

Wide-bandgap semiconductor radiation detectors hold great promise for applications in harsh environments; however, traditional 4H-SiC Schottky detectors often suffer from interface degradation and increased leakage current under high-temperature conditions. To address this bottleneck, this study developed a 4H-SiC radiation detector utilizing a tungsten (W) Schottky contact, in which tungsten-induced interfacial carbide formation enhances thermal stability and suppresses leakage current degradation at high temperatures. Two-dimensional device modeling and transient pulse simulations were performed using Sentaurus TCAD software to elucidate the effects of reverse bias and α-particle energy on the transient current response. Electrical measurement results show that at a reverse bias of −100 V, the leakage current at room temperature is as low as 10 −11 A and rises to only 0.27 μA at 200°C. This low leakage current under varying temperatures is crucial for low-noise signal readout. Alpha-particle testing indicates that charge collection has reached saturation at a bias of −100 V. In combination with a 10 B neutron conversion layer, the fabricated planar detector achieves a thermal neutron detection efficiency of 2.72%, outperforming many previously reported planar wide-bandgap neutron detectors, and can clearly resolve the characteristic α-particle peaks of 1.47 MeV and 1.78 MeV produced by the 10 B neutron capture reaction. This work demonstrates the advantages of W-based Schottky contacts for SiC radiation detectors and provides experimental support for advancing high-temperature-capable α particle and neutron detection technology.